Merge tag 'linux-can-next-for-5.19-20220419' of...

Merge tag 'linux-can-next-for-5.19-20220419' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next

Marc Kleine-Budde says:

====================
pull-request: can-next 2022-04-19

this is a pull request of 17 patches for net-next/master.

The first 2 patches are by me and target the CAN driver
infrastructure. One patch renames a function in the rx_offload helper
the other one updates the CAN bitrate calculation to prefer small bit
rate pre-scalers over larger ones, which is encouraged by the CAN in
Automation.

Kris Bahnsen contributes a patch to fix the links to Technologic
Systems web resources in the sja1000 driver.

Christophe Leroy's patch prepares the mpc5xxx_can driver for upcoming
powerpc header cleanup.

Minghao Chi's patch converts the flexcan driver to use
pm_runtime_resume_and_get().

The next 2 patches target the Xilinx CAN driver. Lukas Bulwahn's patch
fixes an entry in the MAINTAINERS file. A patch by me marks the bit
timing constants as const.

Wolfram Sang's patch documents r8a77961 support on the
renesas,rcar-canfd bindings document.

The next 2 patches are by me and add support for the mcp251863 chip to
the mcp251xfd driver.

The last 7 patches are by Pavel Pisa, Martin Jerabek et al. and add
the ctucanfd driver for the CTU CAN FD IP Core.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/can/ctu,ctucanfd.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/can/ctu,ctucanfd.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: CTU CAN FD Open-source IP Core Device Tree Bindings
+
+description: |
+  Open-source CAN FD IP core developed at the Czech Technical University in Prague
+
+  The core sources and documentation on project page
+    [1] sources : https://gitlab.fel.cvut.cz/canbus/ctucanfd_ip_core
+    [2] datasheet : https://canbus.pages.fel.cvut.cz/ctucanfd_ip_core/doc/Datasheet.pdf
+
+  Integration in Xilinx Zynq SoC based system together with
+  OpenCores SJA1000 compatible controllers
+    [3] project : https://gitlab.fel.cvut.cz/canbus/zynq/zynq-can-sja1000-top
+  Martin Jerabek dimploma thesis with integration and testing
+  framework description
+    [4] PDF : https://dspace.cvut.cz/bitstream/handle/10467/80366/F3-DP-2019-Jerabek-Martin-Jerabek-thesis-2019-canfd.pdf
+
+maintainers:
+  - Pavel Pisa <pisa@cmp.felk.cvut.cz>
+  - Ondrej Ille <ondrej.ille@gmail.com>
+  - Martin Jerabek <martin.jerabek01@gmail.com>
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - const: ctu,ctucanfd-2
+          - const: ctu,ctucanfd
+      - const: ctu,ctucanfd
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    description: |
+      phandle of reference clock (100 MHz is appropriate
+      for FPGA implementation on Zynq-7000 system).
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+
+additionalProperties: false
+
+examples:
+  - |
+    ctu_can_fd_0: can@43c30000 {
+      compatible = "ctu,ctucanfd";
+      interrupts = <0 30 4>;
+      clocks = <&clkc 15>;
+      reg = <0x43c30000 0x10000>;
+    };

Documentation/devicetree/bindings/net/can/microchip,mcp251xfd.yaml

@@ -5,8 +5,8 @@ $id: http://devicetree.org/schemas/net/can/microchip,mcp251xfd.yaml#
 $schema: http://devicetree.org/meta-schemas/core.yaml#
 
 title:
-  Microchip MCP2517FD and MCP2518FD stand-alone CAN controller device tree
-  bindings
+  Microchip MCP2517FD, MCP2518FD and MCP251863 stand-alone CAN
+  controller device tree bindings
 
 maintainers:
   - Marc Kleine-Budde <mkl@pengutronix.de>
@@ -17,13 +17,14 @@ allOf:
 properties:
   compatible:
     oneOf:
-      - const: microchip,mcp2517fd
-        description: for MCP2517FD
+      - enum:
+          - microchip,mcp2517fd
+          - microchip,mcp2518fd
+          - microchip,mcp251xfd
+      - items:
+          - enum:
+              - microchip,mcp251863
           - const: microchip,mcp2518fd
-        description: for MCP2518FD
-      - const: microchip,mcp251xfd
-        description: to autodetect chip variant
-
   reg:
     maxItems: 1
 

Documentation/devicetree/bindings/net/can/renesas,rcar-canfd.yaml

@@ -23,6 +23,7 @@ properties:
               - renesas,r8a774e1-canfd     # RZ/G2H
               - renesas,r8a7795-canfd      # R-Car H3
               - renesas,r8a7796-canfd      # R-Car M3-W
+              - renesas,r8a77961-canfd     # R-Car M3-W+
               - renesas,r8a77965-canfd     # R-Car M3-N
               - renesas,r8a77970-canfd     # R-Car V3M
               - renesas,r8a77980-canfd     # R-Car V3H

Documentation/devicetree/bindings/vendor-prefixes.yaml

@@ -283,6 +283,8 @@ patternProperties:
     description: Shenzen Chuangsiqi Technology Co.,Ltd.
   "^ctera,.*":
     description: CTERA Networks Intl.
+  "^ctu,.*":
+    description: Czech Technical University in Prague
   "^cubietech,.*":
     description: Cubietech, Ltd.
   "^cui,.*":

Documentation/networking/device_drivers/can/ctu/ctucanfd-driver.rst

+.. SPDX-License-Identifier: GPL-2.0-or-later
+
+CTU CAN FD Driver
+=================
+
+Author: Martin Jerabek <martin.jerabek01@gmail.com>
+
+
+About CTU CAN FD IP Core
+------------------------
+
+`CTU CAN FD <https://gitlab.fel.cvut.cz/canbus/ctucanfd_ip_core>`_
+is an open source soft core written in VHDL.
+It originated in 2015 as Ondrej Ille's project
+at the `Department of Measurement <https://meas.fel.cvut.cz/>`_
+of `FEE <http://www.fel.cvut.cz/en/>`_ at `CTU <https://www.cvut.cz/en>`_.
+
+The SocketCAN driver for Xilinx Zynq SoC based MicroZed board
+`Vivado integration <https://gitlab.fel.cvut.cz/canbus/zynq/zynq-can-sja1000-top>`_
+and Intel Cyclone V 5CSEMA4U23C6 based DE0-Nano-SoC Terasic board
+`QSys integration <https://gitlab.fel.cvut.cz/canbus/intel-soc-ctucanfd>`_
+has been developed as well as support for
+`PCIe integration <https://gitlab.fel.cvut.cz/canbus/pcie-ctucanfd>`_ of the core.
+
+In the case of Zynq, the core is connected via the APB system bus, which does
+not have enumeration support, and the device must be specified in Device Tree.
+This kind of devices is called platform device in the kernel and is
+handled by a platform device driver.
+
+The basic functional model of the CTU CAN FD peripheral has been
+accepted into QEMU mainline. See QEMU `CAN emulation support <https://www.qemu.org/docs/master/system/devices/can.html>`_
+for CAN FD buses, host connection and CTU CAN FD core emulation. The development
+version of emulation support can be cloned from ctu-canfd branch of QEMU local
+development `repository <https://gitlab.fel.cvut.cz/canbus/qemu-canbus>`_.
+
+
+About SocketCAN
+---------------
+
+SocketCAN is a standard common interface for CAN devices in the Linux
+kernel. As the name suggests, the bus is accessed via sockets, similarly
+to common network devices. The reasoning behind this is in depth
+described in `Linux SocketCAN <https://www.kernel.org/doc/html/latest/networking/can.html>`_.
+In short, it offers a
+natural way to implement and work with higher layer protocols over CAN,
+in the same way as, e.g., UDP/IP over Ethernet.
+
+Device probe
+~~~~~~~~~~~~
+
+Before going into detail about the structure of a CAN bus device driver,
+let's reiterate how the kernel gets to know about the device at all.
+Some buses, like PCI or PCIe, support device enumeration. That is, when
+the system boots, it discovers all the devices on the bus and reads
+their configuration. The kernel identifies the device via its vendor ID
+and device ID, and if there is a driver registered for this identifier
+combination, its probe method is invoked to populate the driver's
+instance for the given hardware. A similar situation goes with USB, only
+it allows for device hot-plug.
+
+The situation is different for peripherals which are directly embedded
+in the SoC and connected to an internal system bus (AXI, APB, Avalon,
+and others). These buses do not support enumeration, and thus the kernel
+has to learn about the devices from elsewhere. This is exactly what the
+Device Tree was made for.
+
+Device tree
+~~~~~~~~~~~
+
+An entry in device tree states that a device exists in the system, how
+it is reachable (on which bus it resides) and its configuration –
+registers address, interrupts and so on. An example of such a device
+tree is given in .
+
+.. code:: raw
+
+           / {
+               /* ... */
+               amba: amba {
+                   #address-cells = <1>;
+                   #size-cells = <1>;
+                   compatible = "simple-bus";
+
+                   CTU_CAN_FD_0: CTU_CAN_FD@43c30000 {
+                       compatible = "ctu,ctucanfd";
+                       interrupt-parent = <&intc>;
+                       interrupts = <0 30 4>;
+                       clocks = <&clkc 15>;
+                       reg = <0x43c30000 0x10000>;
+                   };
+               };
+           };
+
+
+.. _sec:socketcan:drv:
+
+Driver structure
+~~~~~~~~~~~~~~~~
+
+The driver can be divided into two parts – platform-dependent device
+discovery and set up, and platform-independent CAN network device
+implementation.
+
+.. _sec:socketcan:platdev:
+
+Platform device driver
+^^^^^^^^^^^^^^^^^^^^^^
+
+In the case of Zynq, the core is connected via the AXI system bus, which
+does not have enumeration support, and the device must be specified in
+Device Tree. This kind of devices is called *platform device* in the
+kernel and is handled by a *platform device driver*\  [1]_.
+
+A platform device driver provides the following things:
+
+-  A *probe* function
+
+-  A *remove* function
+
+-  A table of *compatible* devices that the driver can handle
+
+The *probe* function is called exactly once when the device appears (or
+the driver is loaded, whichever happens later). If there are more
+devices handled by the same driver, the *probe* function is called for
+each one of them. Its role is to allocate and initialize resources
+required for handling the device, as well as set up low-level functions
+for the platform-independent layer, e.g., *read_reg* and *write_reg*.
+After that, the driver registers the device to a higher layer, in our
+case as a *network device*.
+
+The *remove* function is called when the device disappears, or the
+driver is about to be unloaded. It serves to free the resources
+allocated in *probe* and to unregister the device from higher layers.
+
+Finally, the table of *compatible* devices states which devices the
+driver can handle. The Device Tree entry ``compatible`` is matched
+against the tables of all *platform drivers*.
+
+.. code:: c
+
+           /* Match table for OF platform binding */
+           static const struct of_device_id ctucan_of_match[] = {
+               { .compatible = "ctu,canfd-2", },
+               { .compatible = "ctu,ctucanfd", },
+               { /* end of list */ },
+           };
+           MODULE_DEVICE_TABLE(of, ctucan_of_match);
+
+           static int ctucan_probe(struct platform_device *pdev);
+           static int ctucan_remove(struct platform_device *pdev);
+
+           static struct platform_driver ctucanfd_driver = {
+               .probe  = ctucan_probe,
+               .remove = ctucan_remove,
+               .driver = {
+                   .name = DRIVER_NAME,
+                   .of_match_table = ctucan_of_match,
+               },
+           };
+           module_platform_driver(ctucanfd_driver);
+
+
+.. _sec:socketcan:netdev:
+
+Network device driver
+^^^^^^^^^^^^^^^^^^^^^
+
+Each network device must support at least these operations:
+
+-  Bring the device up: ``ndo_open``
+
+-  Bring the device down: ``ndo_close``
+
+-  Submit TX frames to the device: ``ndo_start_xmit``
+
+-  Signal TX completion and errors to the network subsystem: ISR
+
+-  Submit RX frames to the network subsystem: ISR and NAPI
+
+There are two possible event sources: the device and the network
+subsystem. Device events are usually signaled via an interrupt, handled
+in an Interrupt Service Routine (ISR). Handlers for the events
+originating in the network subsystem are then specified in
+``struct net_device_ops``.
+
+When the device is brought up, e.g., by calling ``ip link set can0 up``,
+the driver’s function ``ndo_open`` is called. It should validate the
+interface configuration and configure and enable the device. The
+analogous opposite is ``ndo_close``, called when the device is being
+brought down, be it explicitly or implicitly.
+
+When the system should transmit a frame, it does so by calling
+``ndo_start_xmit``, which enqueues the frame into the device. If the
+device HW queue (FIFO, mailboxes or whatever the implementation is)
+becomes full, the ``ndo_start_xmit`` implementation informs the network
+subsystem that it should stop the TX queue (via ``netif_stop_queue``).
+It is then re-enabled later in ISR when the device has some space
+available again and is able to enqueue another frame.
+
+All the device events are handled in ISR, namely:
+
+#. **TX completion**. When the device successfully finishes transmitting
+   a frame, the frame is echoed locally. On error, an informative error
+   frame [2]_ is sent to the network subsystem instead. In both cases,
+   the software TX queue is resumed so that more frames may be sent.
+
+#. **Error condition**. If something goes wrong (e.g., the device goes
+   bus-off or RX overrun happens), error counters are updated, and
+   informative error frames are enqueued to SW RX queue.
+
+#. **RX buffer not empty**. In this case, read the RX frames and enqueue
+   them to SW RX queue. Usually NAPI is used as a middle layer (see ).
+
+.. _sec:socketcan:napi:
+
+NAPI
+~~~~
+
+The frequency of incoming frames can be high and the overhead to invoke
+the interrupt service routine for each frame can cause significant
+system load. There are multiple mechanisms in the Linux kernel to deal
+with this situation. They evolved over the years of Linux kernel
+development and enhancements. For network devices, the current standard
+is NAPI – *the New API*. It is similar to classical top-half/bottom-half
+interrupt handling in that it only acknowledges the interrupt in the ISR
+and signals that the rest of the processing should be done in softirq
+context. On top of that, it offers the possibility to *poll* for new
+frames for a while. This has a potential to avoid the costly round of
+enabling interrupts, handling an incoming IRQ in ISR, re-enabling the
+softirq and switching context back to softirq.
+
+More detailed documentation of NAPI may be found on the pages of Linux
+Foundation `<https://wiki.linuxfoundation.org/networking/napi>`_.
+
+Integrating the core to Xilinx Zynq
+-----------------------------------
+
+The core interfaces a simple subset of the Avalon
+(search for Intel **Avalon Interface Specifications**)
+bus as it was originally used on
+Alterra FPGA chips, yet Xilinx natively interfaces with AXI
+(search for ARM **AMBA AXI and ACE Protocol Specification AXI3,
+AXI4, and AXI4-Lite, ACE and ACE-Lite**).
+The most obvious solution would be to use
+an Avalon/AXI bridge or implement some simple conversion entity.
+However, the core’s interface is half-duplex with no handshake
+signaling, whereas AXI is full duplex with two-way signaling. Moreover,
+even AXI-Lite slave interface is quite resource-intensive, and the
+flexibility and speed of AXI are not required for a CAN core.
+
+Thus a much simpler bus was chosen – APB (Advanced Peripheral Bus)
+(search for ARM **AMBA APB Protocol Specification**).
+APB-AXI bridge is directly available in
+Xilinx Vivado, and the interface adaptor entity is just a few simple
+combinatorial assignments.
+
+Finally, to be able to include the core in a block diagram as a custom
+IP, the core, together with the APB interface, has been packaged as a
+Vivado component.
+
+CTU CAN FD Driver design
+------------------------
+
+The general structure of a CAN device driver has already been examined
+in . The next paragraphs provide a more detailed description of the CTU
+CAN FD core driver in particular.
+
+Low-level driver
+~~~~~~~~~~~~~~~~
+
+The core is not intended to be used solely with SocketCAN, and thus it
+is desirable to have an OS-independent low-level driver. This low-level
+driver can then be used in implementations of OS driver or directly
+either on bare metal or in a user-space application. Another advantage
+is that if the hardware slightly changes, only the low-level driver
+needs to be modified.
+
+The code [3]_ is in part automatically generated and in part written
+manually by the core author, with contributions of the thesis’ author.
+The low-level driver supports operations such as: set bit timing, set
+controller mode, enable/disable, read RX frame, write TX frame, and so
+on.
+
+Configuring bit timing
+~~~~~~~~~~~~~~~~~~~~~~
+
+On CAN, each bit is divided into four segments: SYNC, PROP, PHASE1, and
+PHASE2. Their duration is expressed in multiples of a Time Quantum
+(details in `CAN Specification, Version 2.0 <http://esd.cs.ucr.edu/webres/can20.pdf>`_, chapter 8).
+When configuring
+bitrate, the durations of all the segments (and time quantum) must be
+computed from the bitrate and Sample Point. This is performed
+independently for both the Nominal bitrate and Data bitrate for CAN FD.
+
+SocketCAN is fairly flexible and offers either highly customized
+configuration by setting all the segment durations manually, or a
+convenient configuration by setting just the bitrate and sample point
+(and even that is chosen automatically per Bosch recommendation if not
+specified). However, each CAN controller may have different base clock
+frequency and different width of segment duration registers. The
+algorithm thus needs the minimum and maximum values for the durations
+(and clock prescaler) and tries to optimize the numbers to fit both the
+constraints and the requested parameters.
+
+.. code:: c
+
+           struct can_bittiming_const {
+               char name[16];      /* Name of the CAN controller hardware */
+               __u32 tseg1_min;    /* Time segment 1 = prop_seg + phase_seg1 */
+               __u32 tseg1_max;
+               __u32 tseg2_min;    /* Time segment 2 = phase_seg2 */
+               __u32 tseg2_max;
+               __u32 sjw_max;      /* Synchronisation jump width */
+               __u32 brp_min;      /* Bit-rate prescaler */
+               __u32 brp_max;
+               __u32 brp_inc;
+           };
+
+
+[lst:can_bittiming_const]
+
+A curious reader will notice that the durations of the segments PROP_SEG
+and PHASE_SEG1 are not determined separately but rather combined and
+then, by default, the resulting TSEG1 is evenly divided between PROP_SEG
+and PHASE_SEG1. In practice, this has virtually no consequences as the
+sample point is between PHASE_SEG1 and PHASE_SEG2. In CTU CAN FD,
+however, the duration registers ``PROP`` and ``PH1`` have different
+widths (6 and 7 bits, respectively), so the auto-computed values might
+overflow the shorter register and must thus be redistributed among the
+two [4]_.
+
+Handling RX
+~~~~~~~~~~~
+
+Frame reception is handled in NAPI queue, which is enabled from ISR when
+the RXNE (RX FIFO Not Empty) bit is set. Frames are read one by one
+until either no frame is left in the RX FIFO or the maximum work quota
+has been reached for the NAPI poll run (see ). Each frame is then passed
+to the network interface RX queue.
+
+An incoming frame may be either a CAN 2.0 frame or a CAN FD frame. The
+way to distinguish between these two in the kernel is to allocate either
+``struct can_frame`` or ``struct canfd_frame``, the two having different
+sizes. In the controller, the information about the frame type is stored
+in the first word of RX FIFO.
+
+This brings us a chicken-egg problem: we want to allocate the ``skb``
+for the frame, and only if it succeeds, fetch the frame from FIFO;
+otherwise keep it there for later. But to be able to allocate the
+correct ``skb``, we have to fetch the first work of FIFO. There are
+several possible solutions:
+
+#. Read the word, then allocate. If it fails, discard the rest of the
+   frame. When the system is low on memory, the situation is bad anyway.
+
+#. Always allocate ``skb`` big enough for an FD frame beforehand. Then
+   tweak the ``skb`` internals to look like it has been allocated for
+   the smaller CAN 2.0 frame.
+
+#. Add option to peek into the FIFO instead of consuming the word.
+
+#. If the allocation fails, store the read word into driver’s data. On
+   the next try, use the stored word instead of reading it again.
+
+Option 1 is simple enough, but not very satisfying if we could do
+better. Option 2 is not acceptable, as it would require modifying the
+private state of an integral kernel structure. The slightly higher
+memory consumption is just a virtual cherry on top of the “cake”. Option
+3 requires non-trivial HW changes and is not ideal from the HW point of
+view.
+
+Option 4 seems like a good compromise, with its disadvantage being that
+a partial frame may stay in the FIFO for a prolonged time. Nonetheless,
+there may be just one owner of the RX FIFO, and thus no one else should
+see the partial frame (disregarding some exotic debugging scenarios).
+Basides, the driver resets the core on its initialization, so the
+partial frame cannot be “adopted” either. In the end, option 4 was
+selected [5]_.
+
+.. _subsec:ctucanfd:rxtimestamp:
+
+Timestamping RX frames
+^^^^^^^^^^^^^^^^^^^^^^
+
+The CTU CAN FD core reports the exact timestamp when the frame has been
+received. The timestamp is by default captured at the sample point of
+the last bit of EOF but is configurable to be captured at the SOF bit.
+The timestamp source is external to the core and may be up to 64 bits
+wide. At the time of writing, passing the timestamp from kernel to
+userspace is not yet implemented, but is planned in the future.
+
+Handling TX
+~~~~~~~~~~~
+
+The CTU CAN FD core has 4 independent TX buffers, each with its own
+state and priority. When the core wants to transmit, a TX buffer in
+Ready state with the highest priority is selected.
+
+The priorities are 3bit numbers in register TX_PRIORITY
+(nibble-aligned). This should be flexible enough for most use cases.
+SocketCAN, however, supports only one FIFO queue for outgoing
+frames [6]_. The buffer priorities may be used to simulate the FIFO
+behavior by assigning each buffer a distinct priority and *rotating* the
+priorities after a frame transmission is completed.
+
+In addition to priority rotation, the SW must maintain head and tail
+pointers into the FIFO formed by the TX buffers to be able to determine
+which buffer should be used for next frame (``txb_head``) and which
+should be the first completed one (``txb_tail``). The actual buffer
+indices are (obviously) modulo 4 (number of TX buffers), but the
+pointers must be at least one bit wider to be able to distinguish
+between FIFO full and FIFO empty – in this situation,
+:math:`txb\_head \equiv txb\_tail\ (\textrm{mod}\ 4)`. An example of how
+the FIFO is maintained, together with priority rotation, is depicted in
+
+|
+
++------+---+---+---+---+
+| TXB# | 0 | 1 | 2 | 3 |
++======+===+===+===+===+
+| Seq  | A | B | C |   |
++------+---+---+---+---+
+| Prio | 7 | 6 | 5 | 4 |
++------+---+---+---+---+
+|      |   | T |   | H |
++------+---+---+---+---+
+
+|
+
++------+---+---+---+---+
+| TXB# | 0 | 1 | 2 | 3 |
++======+===+===+===+===+
+| Seq  |   | B | C |   |
++------+---+---+---+---+
+| Prio | 4 | 7 | 6 | 5 |
++------+---+---+---+---+
+|      |   | T |   | H |
++------+---+---+---+---+
+
+|
+
++------+---+---+---+---+----+
+| TXB# | 0 | 1 | 2 | 3 | 0’ |
++======+===+===+===+===+====+
+| Seq  | E | B | C | D |    |
++------+---+---+---+---+----+
+| Prio | 4 | 7 | 6 | 5 |    |
++------+---+---+---+---+----+
+|      |   | T |   |   | H  |
++------+---+---+---+---+----+
+
+|
+
+.. figure:: fsm_txt_buffer_user.svg
+
+   TX Buffer states with possible transitions
+
+.. _subsec:ctucanfd:txtimestamp:
+
+Timestamping TX frames
+^^^^^^^^^^^^^^^^^^^^^^
+
+When submitting a frame to a TX buffer, one may specify the timestamp at
+which the frame should be transmitted. The frame transmission may start
+later, but not sooner. Note that the timestamp does not participate in
+buffer prioritization – that is decided solely by the mechanism
+described above.
+
+Support for time-based packet transmission was recently merged to Linux
+v4.19 `Time-based packet transmission <https://lwn.net/Articles/748879/>`_,
+but it remains yet to be researched
+whether this functionality will be practical for CAN.
+
+Also similarly to retrieving the timestamp of RX frames, the core
+supports retrieving the timestamp of TX frames – that is the time when
+the frame was successfully delivered. The particulars are very similar
+to timestamping RX frames and are described in .
+
+Handling RX buffer overrun
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+When a received frame does no more fit into the hardware RX FIFO in its
+entirety, RX FIFO overrun flag (STATUS[DOR]) is set and Data Overrun
+Interrupt (DOI) is triggered. When servicing the interrupt, care must be
+taken first to clear the DOR flag (via COMMAND[CDO]) and after that
+clear the DOI interrupt flag. Otherwise, the interrupt would be
+immediately [7]_ rearmed.
+
+**Note**: During development, it was discussed whether the internal HW
+pipelining cannot disrupt this clear sequence and whether an additional
+dummy cycle is necessary between clearing the flag and the interrupt. On
+the Avalon interface, it indeed proved to be the case, but APB being
+safe because it uses 2-cycle transactions. Essentially, the DOR flag
+would be cleared, but DOI register’s Preset input would still be high
+the cycle when the DOI clear request would also be applied (by setting
+the register’s Reset input high). As Set had higher priority than Reset,
+the DOI flag would not be reset. This has been already fixed by swapping
+the Set/Reset priority (see issue #187).
+
+Reporting Error Passive and Bus Off conditions
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+It may be desirable to report when the node reaches *Error Passive*,
+*Error Warning*, and *Bus Off* conditions. The driver is notified about
+error state change by an interrupt (EPI, EWLI), and then proceeds to
+determine the core’s error state by reading its error counters.
+
+There is, however, a slight race condition here – there is a delay
+between the time when the state transition occurs (and the interrupt is
+triggered) and when the error counters are read. When EPI is received,
+the node may be either *Error Passive* or *Bus Off*. If the node goes
+*Bus Off*, it obviously remains in the state until it is reset.
+Otherwise, the node is *or was* *Error Passive*. However, it may happen
+that the read state is *Error Warning* or even *Error Active*. It may be
+unclear whether and what exactly to report in that case, but I
+personally entertain the idea that the past error condition should still
+be reported. Similarly, when EWLI is received but the state is later
+detected to be *Error Passive*, *Error Passive* should be reported.
+
+
+CTU CAN FD Driver Sources Reference
+-----------------------------------
+
+.. kernel-doc:: drivers/net/can/ctucanfd/ctucanfd.h
+   :internal:
+
+.. kernel-doc:: drivers/net/can/ctucanfd/ctucanfd_base.c
+   :internal:
+
+.. kernel-doc:: drivers/net/can/ctucanfd/ctucanfd_pci.c
+   :internal:
+
+.. kernel-doc:: drivers/net/can/ctucanfd/ctucanfd_platform.c
+   :internal:
+
+CTU CAN FD IP Core and Driver Development Acknowledgment
+---------------------------------------------------------
+
+* Odrej Ille <illeondr@fel.cvut.cz>
+
+  * started the project as student at Department of Measurement, FEE, CTU
+  * invested great amount of personal time and enthusiasm to the project over years
+  * worked on more funded tasks
+
+* `Department of Measurement <https://meas.fel.cvut.cz/>`_,
+  `Faculty of Electrical Engineering <http://www.fel.cvut.cz/en/>`_,
+  `Czech Technical University <https://www.cvut.cz/en>`_
+
+  * is the main investor into the project over many years
+  * uses project in their CAN/CAN FD diagnostics framework for `Skoda Auto <https://www.skoda-auto.cz/>`_
+
+* `Digiteq Automotive <https://www.digiteqautomotive.com/en>`_
+
+  * funding of the project CAN FD Open Cores Support Linux Kernel Based Systems
+  * negotiated and paid CTU to allow public access to the project
+  * provided additional funding of the work
+
+* `Department of Control Engineering <https://control.fel.cvut.cz/en>`_,
+  `Faculty of Electrical Engineering <http://www.fel.cvut.cz/en/>`_,
+  `Czech Technical University <https://www.cvut.cz/en>`_
+
+  * solving the project CAN FD Open Cores Support Linux Kernel Based Systems
+  * providing GitLab management
+  * virtual servers and computational power for continuous integration
+  * providing hardware for HIL continuous integration tests
+
+* `PiKRON Ltd. <http://pikron.com/>`_
+
+  * minor funding to initiate preparation of the project open-sourcing
+
+* Petr Porazil <porazil@pikron.com>
+
+  * design of PCIe transceiver addon board and assembly of boards
+  * design and assembly of MZ_APO baseboard for MicroZed/Zynq based system
+
+* Martin Jerabek <martin.jerabek01@gmail.com>
+
+  * Linux driver development
+  * continuous integration platform architect and GHDL updates
+  * theses `Open-source and Open-hardware CAN FD Protocol Support <https://dspace.cvut.cz/bitstream/handle/10467/80366/F3-DP-2019-Jerabek-Martin-Jerabek-thesis-2019-canfd.pdf>`_
+
+* Jiri Novak <jnovak@fel.cvut.cz>
+
+  * project initiation, management and use at Department of Measurement, FEE, CTU
+
+* Pavel Pisa <pisa@cmp.felk.cvut.cz>
+
+  * initiate open-sourcing, project coordination, management at Department of Control Engineering, FEE, CTU
+
+* Jaroslav Beran<jara.beran@gmail.com>
+
+ * system integration for Intel SoC, core and driver testing and updates
+
+* Carsten Emde (`OSADL <https://www.osadl.org/>`_)
+
+ * provided OSADL expertise to discuss IP core licensing
+ * pointed to possible deadlock for LGPL and CAN bus possible patent case which lead to relicense IP core design to BSD like license
+
+* Reiner Zitzmann and Holger Zeltwanger (`CAN in Automation <https://www.can-cia.org/>`_)
+
+ * provided suggestions and help to inform community about the project and invited us to events focused on CAN bus future development directions
+
+* Jan Charvat
+
+ * implemented CTU CAN FD functional model for QEMU which has been integrated into QEMU mainline (`docs/system/devices/can.rst <https://www.qemu.org/docs/master/system/devices/can.html>`_)
+ * Bachelor theses Model of CAN FD Communication Controller for QEMU Emulator
+
+Notes
+-----
+
+
+.. [1]
+   Other buses have their own specific driver interface to set up the
+   device.
+
+.. [2]
+   Not to be mistaken with CAN Error Frame. This is a ``can_frame`` with
+   ``CAN_ERR_FLAG`` set and some error info in its ``data`` field.
+
+.. [3]
+   Available in CTU CAN FD repository
+   `<https://gitlab.fel.cvut.cz/canbus/ctucanfd_ip_core>`_
+
+.. [4]
+   As is done in the low-level driver functions
+   ``ctucan_hw_set_nom_bittiming`` and
+   ``ctucan_hw_set_data_bittiming``.
+
+.. [5]
+   At the time of writing this thesis, option 1 is still being used and
+   the modification is queued in gitlab issue #222
+
+.. [6]
+   Strictly speaking, multiple CAN TX queues are supported since v4.19
+   `can: enable multi-queue for SocketCAN devices <https://lore.kernel.org/patchwork/patch/913526/>`_ but no mainline driver is using
+   them yet.
+
+.. [7]
+   Or rather in the next clock cycle

Documentation/networking/device_drivers/can/ctu/fsm_txt_buffer_user.svg

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+   <text transform="matrix(.264583 0 0 .264583 107.574 155.948)" x="38.824219" y="9.1171875" filter="url(#filter1204)" font-size="10.6667px" text-align="center" style="line-height:1.1" xml:space="preserve"><tspan x="38.824219" y="9.1171875" text-align="center">Retransmit</tspan><tspan x="38.824219" y="20.850557" text-align="center">limit reached or</tspan><tspan x="38.824219" y="32.583927" text-align="center">node went bus off</tspan><tspan x="38.824219" y="44.317299" text-align="center"/></text>
+   <text transform="matrix(.264583 0 0 .264583 60.7127 177.384)" x="38.824539" y="9.1173134" filter="url(#filter1204-6)" font-size="12px" text-align="center" style="line-height:1.1" xml:space="preserve"><tspan x="38.824539" y="9.1173134" font-size="12px" stroke-width="3.77953" text-align="center" text-anchor="middle">Transmission result</tspan></text>
+   <text transform="matrix(.264583 0 0 .264583 45.6885 173.226)" x="57.727047" y="9.11724" filter="url(#filter1204-6-9)" font-size="12px" text-align="center" style="line-height:1.1" xml:space="preserve"><tspan x="57.727047" y="9.11724" font-size="12px" stroke-width="3.77953" text-align="center" text-anchor="middle">Legend:</tspan></text>
+  </g>
+  <g fill="#2aa1ff" font-size="12px" stroke-width="3.77953" text-anchor="middle">
+   <text transform="matrix(.264583 0 0 .264583 57.0045 182.079)" x="57.727047" y="9.11724" filter="url(#filter1204-6-2)" text-align="center" style="line-height:1.1" xml:space="preserve"><tspan x="57.727047" y="9.11724" fill="#2aa1ff" font-size="12px" stroke-width="3.77953" text-align="center" text-anchor="middle">SW command</tspan></text>
+   <text transform="matrix(.264583 0 0 .264583 57.7865 110.104)" x="40.822609" y="9.11724" filter="url(#filter1204-6-2-9)" text-align="center" style="line-height:1.1" xml:space="preserve"><tspan x="40.822609" y="9.11724" fill="#2aa1ff" font-size="12px" stroke-width="3.77953" text-align="center" text-anchor="middle">Set ready</tspan></text>
+   <text transform="matrix(.264583 0 0 .264583 116.893 107.491)" x="28.049065" y="9.1172523" filter="url(#filter1204-6-2-9-4)" text-align="center" style="line-height:1.1" xml:space="preserve"><tspan x="28.049065" y="9.1172523" fill="#2aa1ff" font-size="12px" stroke-width="3.77953" text-align="center" text-anchor="middle">Set ready</tspan></text>
+   <text transform="matrix(.264583 0 0 .264583 87.5687 166.324)" x="28.049065" y="9.1172523" filter="url(#filter1204-6-2-9-1)" text-align="center" style="line-height:1.1" xml:space="preserve"><tspan x="28.049065" y="9.1172523" fill="#2aa1ff" font-size="12px" stroke-width="3.77953" text-align="center" text-anchor="middle">Set empty</tspan></text>
+   <text transform="matrix(.264583 0 0 .264583 106.53 113.074)" x="30.228771" y="8.9063139" filter="url(#filter1204-6-2-9-1-3)" text-align="center" style="line-height:1.1" xml:space="preserve"><tspan x="30.228771" y="8.9063139" fill="#2aa1ff" font-size="12px" stroke-width="3.77953" text-align="center" text-anchor="middle">Set abort</tspan></text>
+  </g>
+ </g>
+</svg>

MAINTAINERS

@@ -5234,6 +5234,14 @@ T:	git git://linuxtv.org/media_tree.git
 F:	Documentation/devicetree/bindings/media/allwinner,sun6i-a31-csi.yaml
 F:	drivers/media/platform/sunxi/sun6i-csi/
 
+CTU CAN FD DRIVER
+M:	Pavel Pisa <pisa@cmp.felk.cvut.cz>
+M:	Ondrej Ille <ondrej.ille@gmail.com>
+L:	linux-can@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/net/can/ctu,ctucanfd.yaml
+F:	drivers/net/can/ctucanfd/
+
 CW1200 WLAN driver
 M:	Solomon Peachy <pizza@shaftnet.org>
 S:	Maintained
@@ -21632,7 +21640,7 @@ M:	Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
 R:	Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
 L:	linux-can@vger.kernel.org
 S:	Maintained
-F:	Documentation/devicetree/bindings/net/can/xilinx_can.txt
+F:	Documentation/devicetree/bindings/net/can/xilinx,can.yaml
 F:	drivers/net/can/xilinx_can.c
 
 XILINX GPIO DRIVER

drivers/net/can/Kconfig

@@ -170,6 +170,7 @@ config PCH_CAN
 
 source "drivers/net/can/c_can/Kconfig"
 source "drivers/net/can/cc770/Kconfig"
+source "drivers/net/can/ctucanfd/Kconfig"
 source "drivers/net/can/ifi_canfd/Kconfig"
 source "drivers/net/can/m_can/Kconfig"
 source "drivers/net/can/mscan/Kconfig"

drivers/net/can/Makefile

@@ -16,6 +16,7 @@ obj-y				+= softing/
 obj-$(CONFIG_CAN_AT91)		+= at91_can.o
 obj-$(CONFIG_CAN_CC770)		+= cc770/
 obj-$(CONFIG_CAN_C_CAN)		+= c_can/
+obj-$(CONFIG_CAN_CTUCANFD)	+= ctucanfd/
 obj-$(CONFIG_CAN_FLEXCAN)	+= flexcan/
 obj-$(CONFIG_CAN_GRCAN)		+= grcan.o
 obj-$(CONFIG_CAN_IFI_CANFD)	+= ifi_canfd/

drivers/net/can/ctucanfd/Kconfig

+config CAN_CTUCANFD
+	tristate "CTU CAN-FD IP core"
+	help
+	  This driver adds support for the CTU CAN FD open-source IP core.
+	  More documentation and core sources at project page
+	  (https://gitlab.fel.cvut.cz/canbus/ctucanfd_ip_core).
+	  The core integration to Xilinx Zynq system as platform driver
+	  is available (https://gitlab.fel.cvut.cz/canbus/zynq/zynq-can-sja1000-top).
+	  Implementation on Intel FPGA-based PCI Express board is available
+	  from project (https://gitlab.fel.cvut.cz/canbus/pcie-ctucanfd) and
+	  on Intel SoC from project (https://gitlab.fel.cvut.cz/canbus/intel-soc-ctucanfd).
+	  Guidepost CTU FEE CAN bus projects page https://canbus.pages.fel.cvut.cz/ .
+
+config CAN_CTUCANFD_PCI
+	tristate "CTU CAN-FD IP core PCI/PCIe driver"
+	depends on CAN_CTUCANFD
+	depends on PCI
+	help
+	  This driver adds PCI/PCIe support for CTU CAN-FD IP core.
+	  The project providing FPGA design for Intel EP4CGX15 based DB4CGX15
+	  PCIe board with PiKRON.com designed transceiver riser shield is available
+	  at https://gitlab.fel.cvut.cz/canbus/pcie-ctucanfd .
+
+config CAN_CTUCANFD_PLATFORM
+	tristate "CTU CAN-FD IP core platform (FPGA, SoC) driver"
+	depends on CAN_CTUCANFD
+	depends on OF || COMPILE_TEST
+	help
+	  The core has been tested together with OpenCores SJA1000
+	  modified to be CAN FD frames tolerant on MicroZed Zynq based
+	  MZ_APO education kits designed by Petr Porazil from PiKRON.com
+	  company. FPGA design https://gitlab.fel.cvut.cz/canbus/zynq/zynq-can-sja1000-top.
+	  The kit description at the Computer Architectures course pages
+	  https://cw.fel.cvut.cz/wiki/courses/b35apo/documentation/mz_apo/start .

drivers/net/can/ctucanfd/Makefile

+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# Makefile for the CTU CAN-FD IP module drivers
+#
+
+obj-$(CONFIG_CAN_CTUCANFD) := ctucanfd.o
+ctucanfd-y := ctucanfd_base.o
+
+obj-$(CONFIG_CAN_CTUCANFD_PCI) += ctucanfd_pci.o
+obj-$(CONFIG_CAN_CTUCANFD_PLATFORM) += ctucanfd_platform.o

drivers/net/can/ctucanfd/ctucanfd.h

+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*******************************************************************************
+ *
+ * CTU CAN FD IP Core
+ *
+ * Copyright (C) 2015-2018 Ondrej Ille <ondrej.ille@gmail.com> FEE CTU
+ * Copyright (C) 2018-2021 Ondrej Ille <ondrej.ille@gmail.com> self-funded
+ * Copyright (C) 2018-2019 Martin Jerabek <martin.jerabek01@gmail.com> FEE CTU
+ * Copyright (C) 2018-2021 Pavel Pisa <pisa@cmp.felk.cvut.cz> FEE CTU/self-funded
+ *
+ * Project advisors:
+ *     Jiri Novak <jnovak@fel.cvut.cz>
+ *     Pavel Pisa <pisa@cmp.felk.cvut.cz>
+ *
+ * Department of Measurement         (http://meas.fel.cvut.cz/)
+ * Faculty of Electrical Engineering (http://www.fel.cvut.cz)
+ * Czech Technical University        (http://www.cvut.cz/)
+ ******************************************************************************/
+
+#ifndef __CTUCANFD__
+#define __CTUCANFD__
+
+#include <linux/netdevice.h>
+#include <linux/can/dev.h>
+#include <linux/list.h>
+
+enum ctu_can_fd_can_registers;
+
+struct ctucan_priv {
+	struct can_priv can; /* must be first member! */
+
+	void __iomem *mem_base;
+	u32 (*read_reg)(struct ctucan_priv *priv,
+			enum ctu_can_fd_can_registers reg);
+	void (*write_reg)(struct ctucan_priv *priv,
+			  enum ctu_can_fd_can_registers reg, u32 val);
+
+	unsigned int txb_head;
+	unsigned int txb_tail;
+	u32 txb_prio;
+	unsigned int ntxbufs;
+	spinlock_t tx_lock; /* spinlock to serialize allocation and processing of TX buffers */
+
+	struct napi_struct napi;
+	struct device *dev;
+	struct clk *can_clk;
+
+	int irq_flags;
+	unsigned long drv_flags;
+
+	u32 rxfrm_first_word;
+
+	struct list_head peers_on_pdev;
+};
+
+/**
+ * ctucan_probe_common - Device type independent registration call
+ *
+ * This function does all the memory allocation and registration for the CAN
+ * device.
+ *
+ * @dev:	Handle to the generic device structure
+ * @addr:	Base address of CTU CAN FD core address
+ * @irq:	Interrupt number
+ * @ntxbufs:	Number of implemented Tx buffers
+ * @can_clk_rate: Clock rate, if 0 then clock are taken from device node
+ * @pm_enable_call: Whether pm_runtime_enable should be called
+ * @set_drvdata_fnc: Function to set network driver data for physical device
+ *
+ * Return: 0 on success and failure value on error
+ */
+int ctucan_probe_common(struct device *dev, void __iomem *addr,
+			int irq, unsigned int ntxbufs,
+			unsigned long can_clk_rate,
+			int pm_enable_call,
+			void (*set_drvdata_fnc)(struct device *dev,
+						struct net_device *ndev));
+
+int ctucan_suspend(struct device *dev) __maybe_unused;
+int ctucan_resume(struct device *dev) __maybe_unused;
+
+#endif /*__CTUCANFD__*/

drivers/net/can/ctucanfd/ctucanfd_base.c

+// SPDX-License-Identifier: GPL-2.0-or-later
+/*******************************************************************************
+ *
+ * CTU CAN FD IP Core
+ *
+ * Copyright (C) 2015-2018 Ondrej Ille <ondrej.ille@gmail.com> FEE CTU
+ * Copyright (C) 2018-2021 Ondrej Ille <ondrej.ille@gmail.com> self-funded
+ * Copyright (C) 2018-2019 Martin Jerabek <martin.jerabek01@gmail.com> FEE CTU
+ * Copyright (C) 2018-2022 Pavel Pisa <pisa@cmp.felk.cvut.cz> FEE CTU/self-funded
+ *
+ * Project advisors:
+ *     Jiri Novak <jnovak@fel.cvut.cz>
+ *     Pavel Pisa <pisa@cmp.felk.cvut.cz>
+ *
+ * Department of Measurement         (http://meas.fel.cvut.cz/)
+ * Faculty of Electrical Engineering (http://www.fel.cvut.cz)
+ * Czech Technical University        (http://www.cvut.cz/)
+ ******************************************************************************/
+
+#include <linux/clk.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/bitfield.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/can/error.h>
+#include <linux/can/led.h>
+#include <linux/pm_runtime.h>
+#include <linux/version.h>
+
+#include "ctucanfd.h"
+#include "ctucanfd_kregs.h"
+#include "ctucanfd_kframe.h"
+
+#ifdef DEBUG
+#define  ctucan_netdev_dbg(ndev, args...) \
+		netdev_dbg(ndev, args)
+#else
+#define ctucan_netdev_dbg(...) do { } while (0)
+#endif
+
+#define CTUCANFD_ID 0xCAFD
+
+/* TX buffer rotation:
+ * - when a buffer transitions to empty state, rotate order and priorities
+ * - if more buffers seem to transition at the same time, rotate by the number of buffers
+ * - it may be assumed that buffers transition to empty state in FIFO order (because we manage
+ *   priorities that way)
+ * - at frame filling, do not rotate anything, just increment buffer modulo counter
+ */
+
+#define CTUCANFD_FLAG_RX_FFW_BUFFERED	1
+
+#define CTUCAN_STATE_TO_TEXT_ENTRY(st) \
+		[st] = #st
+
+enum ctucan_txtb_status {
+	TXT_NOT_EXIST       = 0x0,
+	TXT_RDY             = 0x1,
+	TXT_TRAN            = 0x2,
+	TXT_ABTP            = 0x3,
+	TXT_TOK             = 0x4,
+	TXT_ERR             = 0x6,
+	TXT_ABT             = 0x7,
+	TXT_ETY             = 0x8,
+};
+
+enum ctucan_txtb_command {
+	TXT_CMD_SET_EMPTY   = 0x01,
+	TXT_CMD_SET_READY   = 0x02,
+	TXT_CMD_SET_ABORT   = 0x04
+};
+
+static const struct can_bittiming_const ctu_can_fd_bit_timing_max = {
+	.name = "ctu_can_fd",
+	.tseg1_min = 2,
+	.tseg1_max = 190,
+	.tseg2_min = 1,
+	.tseg2_max = 63,
+	.sjw_max = 31,
+	.brp_min = 1,
+	.brp_max = 8,
+	.brp_inc = 1,
+};
+
+static const struct can_bittiming_const ctu_can_fd_bit_timing_data_max = {
+	.name = "ctu_can_fd",
+	.tseg1_min = 2,
+	.tseg1_max = 94,
+	.tseg2_min = 1,
+	.tseg2_max = 31,
+	.sjw_max = 31,
+	.brp_min = 1,
+	.brp_max = 2,
+	.brp_inc = 1,
+};
+
+static const char * const ctucan_state_strings[CAN_STATE_MAX] = {
+	CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_ERROR_ACTIVE),
+	CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_ERROR_WARNING),
+	CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_ERROR_PASSIVE),
+	CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_BUS_OFF),
+	CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_STOPPED),
+	CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_SLEEPING)
+};
+
+static void ctucan_write32_le(struct ctucan_priv *priv,
+			      enum ctu_can_fd_can_registers reg, u32 val)
+{
+	iowrite32(val, priv->mem_base + reg);
+}
+
+static void ctucan_write32_be(struct ctucan_priv *priv,
+			      enum ctu_can_fd_can_registers reg, u32 val)
+{
+	iowrite32be(val, priv->mem_base + reg);
+}
+
+static u32 ctucan_read32_le(struct ctucan_priv *priv,
+			    enum ctu_can_fd_can_registers reg)
+{
+	return ioread32(priv->mem_base + reg);
+}
+
+static u32 ctucan_read32_be(struct ctucan_priv *priv,
+			    enum ctu_can_fd_can_registers reg)
+{
+	return ioread32be(priv->mem_base + reg);
+}
+
+static inline void ctucan_write32(struct ctucan_priv *priv, enum ctu_can_fd_can_registers reg,
+				  u32 val)
+{
+	priv->write_reg(priv, reg, val);
+}
+
+static inline u32 ctucan_read32(struct ctucan_priv *priv, enum ctu_can_fd_can_registers reg)
+{
+	return priv->read_reg(priv, reg);
+}
+
+static void ctucan_write_txt_buf(struct ctucan_priv *priv, enum ctu_can_fd_can_registers buf_base,
+				 u32 offset, u32 val)
+{
+	priv->write_reg(priv, buf_base + offset, val);
+}
+
+#define CTU_CAN_FD_TXTNF(priv) (!!FIELD_GET(REG_STATUS_TXNF, ctucan_read32(priv, CTUCANFD_STATUS)))
+#define CTU_CAN_FD_ENABLED(priv) (!!FIELD_GET(REG_MODE_ENA, ctucan_read32(priv, CTUCANFD_MODE)))
+
+/**
+ * ctucan_state_to_str() - Converts CAN controller state code to corresponding text
+ * @state:	CAN controller state code
+ *
+ * Return: Pointer to string representation of the error state
+ */
+static const char *ctucan_state_to_str(enum can_state state)
+{
+	const char *txt = NULL;
+
+	if (state >= 0 && state < CAN_STATE_MAX)
+		txt = ctucan_state_strings[state];
+	return txt ? txt : "UNKNOWN";
+}
+
+/**
+ * ctucan_reset() - Issues software reset request to CTU CAN FD
+ * @ndev:	Pointer to net_device structure
+ *
+ * Return: 0 for success, -%ETIMEDOUT if CAN controller does not leave reset
+ */
+static int ctucan_reset(struct net_device *ndev)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	int i = 100;
+
+	ctucan_netdev_dbg(ndev, "%s\n", __func__);
+
+	ctucan_write32(priv, CTUCANFD_MODE, REG_MODE_RST);
+	clear_bit(CTUCANFD_FLAG_RX_FFW_BUFFERED, &priv->drv_flags);
+
+	do {
+		u16 device_id = FIELD_GET(REG_DEVICE_ID_DEVICE_ID,
+					  ctucan_read32(priv, CTUCANFD_DEVICE_ID));
+
+		if (device_id == 0xCAFD)
+			return 0;
+		if (!i--) {
+			netdev_warn(ndev, "device did not leave reset\n");
+			return -ETIMEDOUT;
+		}
+		usleep_range(100, 200);
+	} while (1);
+}
+
+/**
+ * ctucan_set_btr() - Sets CAN bus bit timing in CTU CAN FD
+ * @ndev:	Pointer to net_device structure
+ * @bt:		Pointer to Bit timing structure
+ * @nominal:	True - Nominal bit timing, False - Data bit timing
+ *
+ * Return: 0 - OK, -%EPERM if controller is enabled
+ */
+static int ctucan_set_btr(struct net_device *ndev, struct can_bittiming *bt, bool nominal)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	int max_ph1_len = 31;
+	u32 btr = 0;
+	u32 prop_seg = bt->prop_seg;
+	u32 phase_seg1 = bt->phase_seg1;
+
+	if (CTU_CAN_FD_ENABLED(priv)) {
+		netdev_err(ndev, "BUG! Cannot set bittiming - CAN is enabled\n");
+		return -EPERM;
+	}
+
+	if (nominal)
+		max_ph1_len = 63;
+
+	/* The timing calculation functions have only constraints on tseg1, which is prop_seg +
+	 * phase1_seg combined. tseg1 is then split in half and stored into prog_seg and phase_seg1.
+	 * In CTU CAN FD, PROP is 6/7 bits wide but PH1 only 6/5, so we must re-distribute the
+	 * values here.
+	 */
+	if (phase_seg1 > max_ph1_len) {
+		prop_seg += phase_seg1 - max_ph1_len;
+		phase_seg1 = max_ph1_len;
+		bt->prop_seg = prop_seg;
+		bt->phase_seg1 = phase_seg1;
+	}
+
+	if (nominal) {
+		btr = FIELD_PREP(REG_BTR_PROP, prop_seg);
+		btr |= FIELD_PREP(REG_BTR_PH1, phase_seg1);
+		btr |= FIELD_PREP(REG_BTR_PH2, bt->phase_seg2);
+		btr |= FIELD_PREP(REG_BTR_BRP, bt->brp);
+		btr |= FIELD_PREP(REG_BTR_SJW, bt->sjw);
+
+		ctucan_write32(priv, CTUCANFD_BTR, btr);
+	} else {
+		btr = FIELD_PREP(REG_BTR_FD_PROP_FD, prop_seg);
+		btr |= FIELD_PREP(REG_BTR_FD_PH1_FD, phase_seg1);
+		btr |= FIELD_PREP(REG_BTR_FD_PH2_FD, bt->phase_seg2);
+		btr |= FIELD_PREP(REG_BTR_FD_BRP_FD, bt->brp);
+		btr |= FIELD_PREP(REG_BTR_FD_SJW_FD, bt->sjw);
+
+		ctucan_write32(priv, CTUCANFD_BTR_FD, btr);
+	}
+
+	return 0;
+}
+
+/**
+ * ctucan_set_bittiming() - CAN set nominal bit timing routine
+ * @ndev:	Pointer to net_device structure
+ *
+ * Return: 0 on success, -%EPERM on error
+ */
+static int ctucan_set_bittiming(struct net_device *ndev)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	struct can_bittiming *bt = &priv->can.bittiming;
+
+	ctucan_netdev_dbg(ndev, "%s\n", __func__);
+
+	/* Note that bt may be modified here */
+	return ctucan_set_btr(ndev, bt, true);
+}
+
+/**
+ * ctucan_set_data_bittiming() - CAN set data bit timing routine
+ * @ndev:	Pointer to net_device structure
+ *
+ * Return: 0 on success, -%EPERM on error
+ */
+static int ctucan_set_data_bittiming(struct net_device *ndev)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	struct can_bittiming *dbt = &priv->can.data_bittiming;
+
+	ctucan_netdev_dbg(ndev, "%s\n", __func__);
+
+	/* Note that dbt may be modified here */
+	return ctucan_set_btr(ndev, dbt, false);
+}
+
+/**
+ * ctucan_set_secondary_sample_point() - Sets secondary sample point in CTU CAN FD
+ * @ndev:	Pointer to net_device structure
+ *
+ * Return: 0 on success, -%EPERM if controller is enabled
+ */
+static int ctucan_set_secondary_sample_point(struct net_device *ndev)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	struct can_bittiming *dbt = &priv->can.data_bittiming;
+	int ssp_offset = 0;
+	u32 ssp_cfg = 0; /* No SSP by default */
+
+	ctucan_netdev_dbg(ndev, "%s\n", __func__);
+
+	if (CTU_CAN_FD_ENABLED(priv)) {
+		netdev_err(ndev, "BUG! Cannot set SSP - CAN is enabled\n");
+		return -EPERM;
+	}
+
+	/* Use SSP for bit-rates above 1 Mbits/s */
+	if (dbt->bitrate > 1000000) {
+		/* Calculate SSP in minimal time quanta */
+		ssp_offset = (priv->can.clock.freq / 1000) * dbt->sample_point / dbt->bitrate;
+
+		if (ssp_offset > 127) {
+			netdev_warn(ndev, "SSP offset saturated to 127\n");
+			ssp_offset = 127;
+		}
+
+		ssp_cfg = FIELD_PREP(REG_TRV_DELAY_SSP_OFFSET, ssp_offset);
+		ssp_cfg |= FIELD_PREP(REG_TRV_DELAY_SSP_SRC, 0x1);
+	}
+
+	ctucan_write32(priv, CTUCANFD_TRV_DELAY, ssp_cfg);
+
+	return 0;
+}
+
+/**
+ * ctucan_set_mode() - Sets CTU CAN FDs mode
+ * @priv:	Pointer to private data
+ * @mode:	Pointer to controller modes to be set
+ */
+static void ctucan_set_mode(struct ctucan_priv *priv, const struct can_ctrlmode *mode)
+{
+	u32 mode_reg = ctucan_read32(priv, CTUCANFD_MODE);
+
+	mode_reg = (mode->flags & CAN_CTRLMODE_LOOPBACK) ?
+			(mode_reg | REG_MODE_ILBP) :
+			(mode_reg & ~REG_MODE_ILBP);
+
+	mode_reg = (mode->flags & CAN_CTRLMODE_LISTENONLY) ?
+			(mode_reg | REG_MODE_BMM) :
+			(mode_reg & ~REG_MODE_BMM);
+
+	mode_reg = (mode->flags & CAN_CTRLMODE_FD) ?
+			(mode_reg | REG_MODE_FDE) :
+			(mode_reg & ~REG_MODE_FDE);
+
+	mode_reg = (mode->flags & CAN_CTRLMODE_PRESUME_ACK) ?
+			(mode_reg | REG_MODE_ACF) :
+			(mode_reg & ~REG_MODE_ACF);
+
+	mode_reg = (mode->flags & CAN_CTRLMODE_FD_NON_ISO) ?
+			(mode_reg | REG_MODE_NISOFD) :
+			(mode_reg & ~REG_MODE_NISOFD);
+
+	/* One shot mode supported indirectly via Retransmit limit */
+	mode_reg &= ~FIELD_PREP(REG_MODE_RTRTH, 0xF);
+	mode_reg = (mode->flags & CAN_CTRLMODE_ONE_SHOT) ?
+			(mode_reg | REG_MODE_RTRLE) :
+			(mode_reg & ~REG_MODE_RTRLE);
+
+	/* Some bits fixed:
+	 *   TSTM  - Off, User shall not be able to change REC/TEC by hand during operation
+	 */
+	mode_reg &= ~REG_MODE_TSTM;
+
+	ctucan_write32(priv, CTUCANFD_MODE, mode_reg);
+}
+
+/**
+ * ctucan_chip_start() - This routine starts the driver
+ * @ndev:	Pointer to net_device structure
+ *
+ * Routine expects that chip is in reset state. It setups initial
+ * Tx buffers for FIFO priorities, sets bittiming, enables interrupts,
+ * switches core to operational mode and changes controller
+ * state to %CAN_STATE_STOPPED.
+ *
+ * Return: 0 on success and failure value on error
+ */
+static int ctucan_chip_start(struct net_device *ndev)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	u32 int_ena, int_msk;
+	u32 mode_reg;
+	int err;
+	struct can_ctrlmode mode;
+
+	ctucan_netdev_dbg(ndev, "%s\n", __func__);
+
+	priv->txb_prio = 0x01234567;
+	priv->txb_head = 0;
+	priv->txb_tail = 0;
+	ctucan_write32(priv, CTUCANFD_TX_PRIORITY, priv->txb_prio);
+
+	/* Configure bit-rates and ssp */
+	err = ctucan_set_bittiming(ndev);
+	if (err < 0)
+		return err;
+
+	err = ctucan_set_data_bittiming(ndev);
+	if (err < 0)
+		return err;
+
+	err = ctucan_set_secondary_sample_point(ndev);
+	if (err < 0)
+		return err;
+
+	/* Configure modes */
+	mode.flags = priv->can.ctrlmode;
+	mode.mask = 0xFFFFFFFF;
+	ctucan_set_mode(priv, &mode);
+
+	/* Configure interrupts */
+	int_ena = REG_INT_STAT_RBNEI |
+		  REG_INT_STAT_TXBHCI |
+		  REG_INT_STAT_EWLI |
+		  REG_INT_STAT_FCSI;
+
+	/* Bus error reporting -> Allow Error/Arb.lost interrupts */
+	if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) {
+		int_ena |= REG_INT_STAT_ALI |
+			   REG_INT_STAT_BEI;
+	}
+
+	int_msk = ~int_ena; /* Mask all disabled interrupts */
+
+	/* It's after reset, so there is no need to clear anything */
+	ctucan_write32(priv, CTUCANFD_INT_MASK_SET, int_msk);
+	ctucan_write32(priv, CTUCANFD_INT_ENA_SET, int_ena);
+
+	/* Controller enters ERROR_ACTIVE on initial FCSI */
+	priv->can.state = CAN_STATE_STOPPED;
+
+	/* Enable the controller */
+	mode_reg = ctucan_read32(priv, CTUCANFD_MODE);
+	mode_reg |= REG_MODE_ENA;
+	ctucan_write32(priv, CTUCANFD_MODE, mode_reg);
+
+	return 0;
+}
+
+/**
+ * ctucan_do_set_mode() - Sets mode of the driver
+ * @ndev:	Pointer to net_device structure
+ * @mode:	Tells the mode of the driver
+ *
+ * This check the drivers state and calls the corresponding modes to set.
+ *
+ * Return: 0 on success and failure value on error
+ */
+static int ctucan_do_set_mode(struct net_device *ndev, enum can_mode mode)
+{
+	int ret;
+
+	ctucan_netdev_dbg(ndev, "%s\n", __func__);
+
+	switch (mode) {
+	case CAN_MODE_START:
+		ret = ctucan_reset(ndev);
+		if (ret < 0)
+			return ret;
+		ret = ctucan_chip_start(ndev);
+		if (ret < 0) {
+			netdev_err(ndev, "ctucan_chip_start failed!\n");
+			return ret;
+		}
+		netif_wake_queue(ndev);
+		break;
+	default:
+		ret = -EOPNOTSUPP;
+		break;
+	}
+
+	return ret;
+}
+
+/**
+ * ctucan_get_tx_status() - Gets status of TXT buffer
+ * @priv:	Pointer to private data
+ * @buf:	Buffer index (0-based)
+ *
+ * Return: Status of TXT buffer
+ */
+static inline enum ctucan_txtb_status ctucan_get_tx_status(struct ctucan_priv *priv, u8 buf)
+{
+	u32 tx_status = ctucan_read32(priv, CTUCANFD_TX_STATUS);
+	enum ctucan_txtb_status status = (tx_status >> (buf * 4)) & 0x7;
+
+	return status;
+}
+
+/**
+ * ctucan_is_txt_buf_writable() - Checks if frame can be inserted to TXT Buffer
+ * @priv:	Pointer to private data
+ * @buf:	Buffer index (0-based)
+ *
+ * Return: True - Frame can be inserted to TXT Buffer, False - If attempted, frame will not be
+ *	   inserted to TXT Buffer
+ */
+static bool ctucan_is_txt_buf_writable(struct ctucan_priv *priv, u8 buf)
+{
+	enum ctucan_txtb_status buf_status;
+
+	buf_status = ctucan_get_tx_status(priv, buf);
+	if (buf_status == TXT_RDY || buf_status == TXT_TRAN || buf_status == TXT_ABTP)
+		return false;
+
+	return true;
+}
+
+/**
+ * ctucan_insert_frame() - Inserts frame to TXT buffer
+ * @priv:	Pointer to private data
+ * @cf:		Pointer to CAN frame to be inserted
+ * @buf:	TXT Buffer index to which frame is inserted (0-based)
+ * @isfdf:	True - CAN FD Frame, False - CAN 2.0 Frame
+ *
+ * Return: True - Frame inserted successfully
+ *	   False - Frame was not inserted due to one of:
+ *			1. TXT Buffer is not writable (it is in wrong state)
+ *			2. Invalid TXT buffer index
+ *			3. Invalid frame length
+ */
+static bool ctucan_insert_frame(struct ctucan_priv *priv, const struct canfd_frame *cf, u8 buf,
+				bool isfdf)
+{
+	u32 buf_base;
+	u32 ffw = 0;
+	u32 idw = 0;
+	unsigned int i;
+
+	if (buf >= priv->ntxbufs)
+		return false;
+
+	if (!ctucan_is_txt_buf_writable(priv, buf))
+		return false;
+
+	if (cf->len > CANFD_MAX_DLEN)
+		return false;
+
+	/* Prepare Frame format */
+	if (cf->can_id & CAN_RTR_FLAG)
+		ffw |= REG_FRAME_FORMAT_W_RTR;
+
+	if (cf->can_id & CAN_EFF_FLAG)
+		ffw |= REG_FRAME_FORMAT_W_IDE;
+
+	if (isfdf) {
+		ffw |= REG_FRAME_FORMAT_W_FDF;
+		if (cf->flags & CANFD_BRS)
+			ffw |= REG_FRAME_FORMAT_W_BRS;
+	}
+
+	ffw |= FIELD_PREP(REG_FRAME_FORMAT_W_DLC, can_fd_len2dlc(cf->len));
+
+	/* Prepare identifier */
+	if (cf->can_id & CAN_EFF_FLAG)
+		idw = cf->can_id & CAN_EFF_MASK;
+	else
+		idw = FIELD_PREP(REG_IDENTIFIER_W_IDENTIFIER_BASE, cf->can_id & CAN_SFF_MASK);
+
+	/* Write ID, Frame format, Don't write timestamp -> Time triggered transmission disabled */
+	buf_base = (buf + 1) * 0x100;
+	ctucan_write_txt_buf(priv, buf_base, CTUCANFD_FRAME_FORMAT_W, ffw);
+	ctucan_write_txt_buf(priv, buf_base, CTUCANFD_IDENTIFIER_W, idw);
+
+	/* Write Data payload */
+	if (!(cf->can_id & CAN_RTR_FLAG)) {
+		for (i = 0; i < cf->len; i += 4) {
+			u32 data = le32_to_cpu(*(__le32 *)(cf->data + i));
+
+			ctucan_write_txt_buf(priv, buf_base, CTUCANFD_DATA_1_4_W + i, data);
+		}
+	}
+
+	return true;
+}
+
+/**
+ * ctucan_give_txtb_cmd() - Applies command on TXT buffer
+ * @priv:	Pointer to private data
+ * @cmd:	Command to give
+ * @buf:	Buffer index (0-based)
+ */
+static void ctucan_give_txtb_cmd(struct ctucan_priv *priv, enum ctucan_txtb_command cmd, u8 buf)
+{
+	u32 tx_cmd = cmd;
+
+	tx_cmd |= 1 << (buf + 8);
+	ctucan_write32(priv, CTUCANFD_TX_COMMAND, tx_cmd);
+}
+
+/**
+ * ctucan_start_xmit() - Starts the transmission
+ * @skb:	sk_buff pointer that contains data to be Txed
+ * @ndev:	Pointer to net_device structure
+ *
+ * Invoked from upper layers to initiate transmission. Uses the next available free TXT Buffer and
+ * populates its fields to start the transmission.
+ *
+ * Return: %NETDEV_TX_OK on success, %NETDEV_TX_BUSY when no free TXT buffer is available,
+ *         negative return values reserved for error cases
+ */
+static netdev_tx_t ctucan_start_xmit(struct sk_buff *skb, struct net_device *ndev)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	struct canfd_frame *cf = (struct canfd_frame *)skb->data;
+	u32 txtb_id;
+	bool ok;
+	unsigned long flags;
+
+	if (can_dropped_invalid_skb(ndev, skb))
+		return NETDEV_TX_OK;
+
+	if (unlikely(!CTU_CAN_FD_TXTNF(priv))) {
+		netif_stop_queue(ndev);
+		netdev_err(ndev, "BUG!, no TXB free when queue awake!\n");
+		return NETDEV_TX_BUSY;
+	}
+
+	txtb_id = priv->txb_head % priv->ntxbufs;
+	ctucan_netdev_dbg(ndev, "%s: using TXB#%u\n", __func__, txtb_id);
+	ok = ctucan_insert_frame(priv, cf, txtb_id, can_is_canfd_skb(skb));
+
+	if (!ok) {
+		netdev_err(ndev, "BUG! TXNF set but cannot insert frame into TXTB! HW Bug?");
+		kfree_skb(skb);
+		ndev->stats.tx_dropped++;
+		return NETDEV_TX_OK;
+	}
+
+	can_put_echo_skb(skb, ndev, txtb_id, 0);
+
+	spin_lock_irqsave(&priv->tx_lock, flags);
+	ctucan_give_txtb_cmd(priv, TXT_CMD_SET_READY, txtb_id);
+	priv->txb_head++;
+
+	/* Check if all TX buffers are full */
+	if (!CTU_CAN_FD_TXTNF(priv))
+		netif_stop_queue(ndev);
+
+	spin_unlock_irqrestore(&priv->tx_lock, flags);
+
+	return NETDEV_TX_OK;
+}
+
+/**
+ * ctucan_read_rx_frame() - Reads frame from RX FIFO
+ * @priv:	Pointer to CTU CAN FD's private data
+ * @cf:		Pointer to CAN frame struct
+ * @ffw:	Previously read frame format word
+ *
+ * Note: Frame format word must be read separately and provided in 'ffw'.
+ */
+static void ctucan_read_rx_frame(struct ctucan_priv *priv, struct canfd_frame *cf, u32 ffw)
+{
+	u32 idw;
+	unsigned int i;
+	unsigned int wc;
+	unsigned int len;
+
+	idw = ctucan_read32(priv, CTUCANFD_RX_DATA);
+	if (FIELD_GET(REG_FRAME_FORMAT_W_IDE, ffw))
+		cf->can_id = (idw & CAN_EFF_MASK) | CAN_EFF_FLAG;
+	else
+		cf->can_id = (idw >> 18) & CAN_SFF_MASK;
+
+	/* BRS, ESI, RTR Flags */
+	cf->flags = 0;
+	if (FIELD_GET(REG_FRAME_FORMAT_W_FDF, ffw)) {
+		if (FIELD_GET(REG_FRAME_FORMAT_W_BRS, ffw))
+			cf->flags |= CANFD_BRS;
+		if (FIELD_GET(REG_FRAME_FORMAT_W_ESI_RSV, ffw))
+			cf->flags |= CANFD_ESI;
+	} else if (FIELD_GET(REG_FRAME_FORMAT_W_RTR, ffw)) {
+		cf->can_id |= CAN_RTR_FLAG;
+	}
+
+	wc = FIELD_GET(REG_FRAME_FORMAT_W_RWCNT, ffw) - 3;
+
+	/* DLC */
+	if (FIELD_GET(REG_FRAME_FORMAT_W_DLC, ffw) <= 8) {
+		len = FIELD_GET(REG_FRAME_FORMAT_W_DLC, ffw);
+	} else {
+		if (FIELD_GET(REG_FRAME_FORMAT_W_FDF, ffw))
+			len = wc << 2;
+		else
+			len = 8;
+	}
+	cf->len = len;
+	if (unlikely(len > wc * 4))
+		len = wc * 4;
+
+	/* Timestamp - Read and throw away */
+	ctucan_read32(priv, CTUCANFD_RX_DATA);
+	ctucan_read32(priv, CTUCANFD_RX_DATA);
+
+	/* Data */
+	for (i = 0; i < len; i += 4) {
+		u32 data = ctucan_read32(priv, CTUCANFD_RX_DATA);
+		*(__le32 *)(cf->data + i) = cpu_to_le32(data);
+	}
+	while (unlikely(i < wc * 4)) {
+		ctucan_read32(priv, CTUCANFD_RX_DATA);
+		i += 4;
+	}
+}
+
+/**
+ * ctucan_rx() -  Called from CAN ISR to complete the received frame processing
+ * @ndev:	Pointer to net_device structure
+ *
+ * This function is invoked from the CAN isr(poll) to process the Rx frames. It does minimal
+ * processing and invokes "netif_receive_skb" to complete further processing.
+ * Return: 1 when frame is passed to the network layer, 0 when the first frame word is read but
+ *	   system is out of free SKBs temporally and left code to resolve SKB allocation later,
+ *         -%EAGAIN in a case of empty Rx FIFO.
+ */
+static int ctucan_rx(struct net_device *ndev)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	struct net_device_stats *stats = &ndev->stats;
+	struct canfd_frame *cf;
+	struct sk_buff *skb;
+	u32 ffw;
+
+	if (test_bit(CTUCANFD_FLAG_RX_FFW_BUFFERED, &priv->drv_flags)) {
+		ffw = priv->rxfrm_first_word;
+		clear_bit(CTUCANFD_FLAG_RX_FFW_BUFFERED, &priv->drv_flags);
+	} else {
+		ffw = ctucan_read32(priv, CTUCANFD_RX_DATA);
+	}
+
+	if (!FIELD_GET(REG_FRAME_FORMAT_W_RWCNT, ffw))
+		return -EAGAIN;
+
+	if (FIELD_GET(REG_FRAME_FORMAT_W_FDF, ffw))
+		skb = alloc_canfd_skb(ndev, &cf);
+	else
+		skb = alloc_can_skb(ndev, (struct can_frame **)&cf);
+
+	if (unlikely(!skb)) {
+		priv->rxfrm_first_word = ffw;
+		set_bit(CTUCANFD_FLAG_RX_FFW_BUFFERED, &priv->drv_flags);
+		return 0;
+	}
+
+	ctucan_read_rx_frame(priv, cf, ffw);
+
+	stats->rx_bytes += cf->len;
+	stats->rx_packets++;
+	netif_receive_skb(skb);
+
+	return 1;
+}
+
+/**
+ * ctucan_read_fault_state() - Reads CTU CAN FDs fault confinement state.
+ * @priv:	Pointer to private data
+ *
+ * Returns: Fault confinement state of controller
+ */
+static enum can_state ctucan_read_fault_state(struct ctucan_priv *priv)
+{
+	u32 fs;
+	u32 rec_tec;
+	u32 ewl;
+
+	fs = ctucan_read32(priv, CTUCANFD_EWL);
+	rec_tec = ctucan_read32(priv, CTUCANFD_REC);
+	ewl = FIELD_GET(REG_EWL_EW_LIMIT, fs);
+
+	if (FIELD_GET(REG_EWL_ERA, fs)) {
+		if (ewl > FIELD_GET(REG_REC_REC_VAL, rec_tec) &&
+		    ewl > FIELD_GET(REG_REC_TEC_VAL, rec_tec))
+			return CAN_STATE_ERROR_ACTIVE;
+		else
+			return CAN_STATE_ERROR_WARNING;
+	} else if (FIELD_GET(REG_EWL_ERP, fs)) {
+		return CAN_STATE_ERROR_PASSIVE;
+	} else if (FIELD_GET(REG_EWL_BOF, fs)) {
+		return CAN_STATE_BUS_OFF;
+	}
+
+	WARN(true, "Invalid error state");
+	return CAN_STATE_ERROR_PASSIVE;
+}
+
+/**
+ * ctucan_get_rec_tec() - Reads REC/TEC counter values from controller
+ * @priv:	Pointer to private data
+ * @bec:	Pointer to Error counter structure
+ */
+static void ctucan_get_rec_tec(struct ctucan_priv *priv, struct can_berr_counter *bec)
+{
+	u32 err_ctrs = ctucan_read32(priv, CTUCANFD_REC);
+
+	bec->rxerr = FIELD_GET(REG_REC_REC_VAL, err_ctrs);
+	bec->txerr = FIELD_GET(REG_REC_TEC_VAL, err_ctrs);
+}
+
+/**
+ * ctucan_err_interrupt() - Error frame ISR
+ * @ndev:	net_device pointer
+ * @isr:	interrupt status register value
+ *
+ * This is the CAN error interrupt and it will check the type of error and forward the error
+ * frame to upper layers.
+ */
+static void ctucan_err_interrupt(struct net_device *ndev, u32 isr)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	struct net_device_stats *stats = &ndev->stats;
+	struct can_frame *cf;
+	struct sk_buff *skb;
+	enum can_state state;
+	struct can_berr_counter bec;
+	u32 err_capt_alc;
+	int dologerr = net_ratelimit();
+
+	ctucan_get_rec_tec(priv, &bec);
+	state = ctucan_read_fault_state(priv);
+	err_capt_alc = ctucan_read32(priv, CTUCANFD_ERR_CAPT);
+
+	if (dologerr)
+		netdev_info(ndev, "%s: ISR = 0x%08x, rxerr %d, txerr %d, error type %lu, pos %lu, ALC id_field %lu, bit %lu\n",
+			    __func__, isr, bec.rxerr, bec.txerr,
+			    FIELD_GET(REG_ERR_CAPT_ERR_TYPE, err_capt_alc),
+			    FIELD_GET(REG_ERR_CAPT_ERR_POS, err_capt_alc),
+			    FIELD_GET(REG_ERR_CAPT_ALC_ID_FIELD, err_capt_alc),
+			    FIELD_GET(REG_ERR_CAPT_ALC_BIT, err_capt_alc));
+
+	skb = alloc_can_err_skb(ndev, &cf);
+
+	/* EWLI: error warning limit condition met
+	 * FCSI: fault confinement state changed
+	 * ALI:  arbitration lost (just informative)
+	 * BEI:  bus error interrupt
+	 */
+	if (FIELD_GET(REG_INT_STAT_FCSI, isr) || FIELD_GET(REG_INT_STAT_EWLI, isr)) {
+		netdev_info(ndev, "state changes from %s to %s\n",
+			    ctucan_state_to_str(priv->can.state),
+			    ctucan_state_to_str(state));
+
+		if (priv->can.state == state)
+			netdev_warn(ndev,
+				    "current and previous state is the same! (missed interrupt?)\n");
+
+		priv->can.state = state;
+		switch (state) {
+		case CAN_STATE_BUS_OFF:
+			priv->can.can_stats.bus_off++;
+			can_bus_off(ndev);
+			if (skb)
+				cf->can_id |= CAN_ERR_BUSOFF;
+			break;
+		case CAN_STATE_ERROR_PASSIVE:
+			priv->can.can_stats.error_passive++;
+			if (skb) {
+				cf->can_id |= CAN_ERR_CRTL;
+				cf->data[1] = (bec.rxerr > 127) ?
+						CAN_ERR_CRTL_RX_PASSIVE :
+						CAN_ERR_CRTL_TX_PASSIVE;
+				cf->data[6] = bec.txerr;
+				cf->data[7] = bec.rxerr;
+			}
+			break;
+		case CAN_STATE_ERROR_WARNING:
+			priv->can.can_stats.error_warning++;
+			if (skb) {
+				cf->can_id |= CAN_ERR_CRTL;
+				cf->data[1] |= (bec.txerr > bec.rxerr) ?
+					CAN_ERR_CRTL_TX_WARNING :
+					CAN_ERR_CRTL_RX_WARNING;
+				cf->data[6] = bec.txerr;
+				cf->data[7] = bec.rxerr;
+			}
+			break;
+		case CAN_STATE_ERROR_ACTIVE:
+			cf->data[1] = CAN_ERR_CRTL_ACTIVE;
+			cf->data[6] = bec.txerr;
+			cf->data[7] = bec.rxerr;
+			break;
+		default:
+			netdev_warn(ndev, "unhandled error state (%d:%s)!\n",
+				    state, ctucan_state_to_str(state));
+			break;
+		}
+	}
+
+	/* Check for Arbitration Lost interrupt */
+	if (FIELD_GET(REG_INT_STAT_ALI, isr)) {
+		if (dologerr)
+			netdev_info(ndev, "arbitration lost\n");
+		priv->can.can_stats.arbitration_lost++;
+		if (skb) {
+			cf->can_id |= CAN_ERR_LOSTARB;
+			cf->data[0] = CAN_ERR_LOSTARB_UNSPEC;
+		}
+	}
+
+	/* Check for Bus Error interrupt */
+	if (FIELD_GET(REG_INT_STAT_BEI, isr)) {
+		netdev_info(ndev, "bus error\n");
+		priv->can.can_stats.bus_error++;
+		stats->rx_errors++;
+		if (skb) {
+			cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+			cf->data[2] = CAN_ERR_PROT_UNSPEC;
+			cf->data[3] = CAN_ERR_PROT_LOC_UNSPEC;
+		}
+	}
+
+	if (skb) {
+		stats->rx_packets++;
+		stats->rx_bytes += cf->can_dlc;
+		netif_rx(skb);
+	}
+}
+
+/**
+ * ctucan_rx_poll() - Poll routine for rx packets (NAPI)
+ * @napi:	NAPI structure pointer
+ * @quota:	Max number of rx packets to be processed.
+ *
+ * This is the poll routine for rx part. It will process the packets maximux quota value.
+ *
+ * Return: Number of packets received
+ */
+static int ctucan_rx_poll(struct napi_struct *napi, int quota)
+{
+	struct net_device *ndev = napi->dev;
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	int work_done = 0;
+	u32 status;
+	u32 framecnt;
+	int res = 1;
+
+	framecnt = FIELD_GET(REG_RX_STATUS_RXFRC, ctucan_read32(priv, CTUCANFD_RX_STATUS));
+	while (framecnt && work_done < quota && res > 0) {
+		res = ctucan_rx(ndev);
+		work_done++;
+		framecnt = FIELD_GET(REG_RX_STATUS_RXFRC, ctucan_read32(priv, CTUCANFD_RX_STATUS));
+	}
+
+	/* Check for RX FIFO Overflow */
+	status = ctucan_read32(priv, CTUCANFD_STATUS);
+	if (FIELD_GET(REG_STATUS_DOR, status)) {
+		struct net_device_stats *stats = &ndev->stats;
+		struct can_frame *cf;
+		struct sk_buff *skb;
+
+		netdev_info(ndev, "rx_poll: rx fifo overflow\n");
+		stats->rx_over_errors++;
+		stats->rx_errors++;
+		skb = alloc_can_err_skb(ndev, &cf);
+		if (skb) {
+			cf->can_id |= CAN_ERR_CRTL;
+			cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;
+			stats->rx_packets++;
+			stats->rx_bytes += cf->can_dlc;
+			netif_rx(skb);
+		}
+
+		/* Clear Data Overrun */
+		ctucan_write32(priv, CTUCANFD_COMMAND, REG_COMMAND_CDO);
+	}
+
+	if (work_done)
+		can_led_event(ndev, CAN_LED_EVENT_RX);
+
+	if (!framecnt && res != 0) {
+		if (napi_complete_done(napi, work_done)) {
+			/* Clear and enable RBNEI. It is level-triggered, so
+			 * there is no race condition.
+			 */
+			ctucan_write32(priv, CTUCANFD_INT_STAT, REG_INT_STAT_RBNEI);
+			ctucan_write32(priv, CTUCANFD_INT_MASK_CLR, REG_INT_STAT_RBNEI);
+		}
+	}
+
+	return work_done;
+}
+
+/**
+ * ctucan_rotate_txb_prio() - Rotates priorities of TXT Buffers
+ * @ndev:	net_device pointer
+ */
+static void ctucan_rotate_txb_prio(struct net_device *ndev)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	u32 prio = priv->txb_prio;
+
+	prio = (prio << 4) | ((prio >> ((priv->ntxbufs - 1) * 4)) & 0xF);
+	ctucan_netdev_dbg(ndev, "%s: from 0x%08x to 0x%08x\n", __func__, priv->txb_prio, prio);
+	priv->txb_prio = prio;
+	ctucan_write32(priv, CTUCANFD_TX_PRIORITY, prio);
+}
+
+/**
+ * ctucan_tx_interrupt() - Tx done Isr
+ * @ndev:	net_device pointer
+ */
+static void ctucan_tx_interrupt(struct net_device *ndev)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	struct net_device_stats *stats = &ndev->stats;
+	bool first = true;
+	bool some_buffers_processed;
+	unsigned long flags;
+	enum ctucan_txtb_status txtb_status;
+	u32 txtb_id;
+
+	/*  read tx_status
+	 *  if txb[n].finished (bit 2)
+	 *	if ok -> echo
+	 *	if error / aborted -> ?? (find how to handle oneshot mode)
+	 *	txb_tail++
+	 */
+	do {
+		spin_lock_irqsave(&priv->tx_lock, flags);
+
+		some_buffers_processed = false;
+		while ((int)(priv->txb_head - priv->txb_tail) > 0) {
+			txtb_id = priv->txb_tail % priv->ntxbufs;
+			txtb_status = ctucan_get_tx_status(priv, txtb_id);
+
+			ctucan_netdev_dbg(ndev, "TXI: TXB#%u: status 0x%x\n", txtb_id, txtb_status);
+
+			switch (txtb_status) {
+			case TXT_TOK:
+				ctucan_netdev_dbg(ndev, "TXT_OK\n");
+				stats->tx_bytes += can_get_echo_skb(ndev, txtb_id, NULL);
+				stats->tx_packets++;
+				break;
+			case TXT_ERR:
+				/* This indicated that retransmit limit has been reached. Obviously
+				 * we should not echo the frame, but also not indicate any kind of
+				 * error. If desired, it was already reported (possible multiple
+				 * times) on each arbitration lost.
+				 */
+				netdev_warn(ndev, "TXB in Error state\n");
+				can_free_echo_skb(ndev, txtb_id, NULL);
+				stats->tx_dropped++;
+				break;
+			case TXT_ABT:
+				/* Same as for TXT_ERR, only with different cause. We *could*
+				 * re-queue the frame, but multiqueue/abort is not supported yet
+				 * anyway.
+				 */
+				netdev_warn(ndev, "TXB in Aborted state\n");
+				can_free_echo_skb(ndev, txtb_id, NULL);
+				stats->tx_dropped++;
+				break;
+			default:
+				/* Bug only if the first buffer is not finished, otherwise it is
+				 * pretty much expected.
+				 */
+				if (first) {
+					netdev_err(ndev,
+						   "BUG: TXB#%u not in a finished state (0x%x)!\n",
+						   txtb_id, txtb_status);
+					spin_unlock_irqrestore(&priv->tx_lock, flags);
+					/* do not clear nor wake */
+					return;
+				}
+				goto clear;
+			}
+			priv->txb_tail++;
+			first = false;
+			some_buffers_processed = true;
+			/* Adjust priorities *before* marking the buffer as empty. */
+			ctucan_rotate_txb_prio(ndev);
+			ctucan_give_txtb_cmd(priv, TXT_CMD_SET_EMPTY, txtb_id);
+		}
+clear:
+		spin_unlock_irqrestore(&priv->tx_lock, flags);
+
+		/* If no buffers were processed this time, we cannot clear - that would introduce
+		 * a race condition.
+		 */
+		if (some_buffers_processed) {
+			/* Clear the interrupt again. We do not want to receive again interrupt for
+			 * the buffer already handled. If it is the last finished one then it would
+			 * cause log of spurious interrupt.
+			 */
+			ctucan_write32(priv, CTUCANFD_INT_STAT, REG_INT_STAT_TXBHCI);
+		}
+	} while (some_buffers_processed);
+
+	can_led_event(ndev, CAN_LED_EVENT_TX);
+
+	spin_lock_irqsave(&priv->tx_lock, flags);
+
+	/* Check if at least one TX buffer is free */
+	if (CTU_CAN_FD_TXTNF(priv))
+		netif_wake_queue(ndev);
+
+	spin_unlock_irqrestore(&priv->tx_lock, flags);
+}
+
+/**
+ * ctucan_interrupt() - CAN Isr
+ * @irq:	irq number
+ * @dev_id:	device id poniter
+ *
+ * This is the CTU CAN FD ISR. It checks for the type of interrupt
+ * and invokes the corresponding ISR.
+ *
+ * Return:
+ * IRQ_NONE - If CAN device is in sleep mode, IRQ_HANDLED otherwise
+ */
+static irqreturn_t ctucan_interrupt(int irq, void *dev_id)
+{
+	struct net_device *ndev = (struct net_device *)dev_id;
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	u32 isr, icr;
+	u32 imask;
+	int irq_loops;
+
+	ctucan_netdev_dbg(ndev, "%s\n", __func__);
+
+	for (irq_loops = 0; irq_loops < 10000; irq_loops++) {
+		/* Get the interrupt status */
+		isr = ctucan_read32(priv, CTUCANFD_INT_STAT);
+
+		if (!isr)
+			return irq_loops ? IRQ_HANDLED : IRQ_NONE;
+
+		/* Receive Buffer Not Empty Interrupt */
+		if (FIELD_GET(REG_INT_STAT_RBNEI, isr)) {
+			ctucan_netdev_dbg(ndev, "RXBNEI\n");
+			/* Mask RXBNEI the first, then clear interrupt and schedule NAPI. Even if
+			 * another IRQ fires, RBNEI will always be 0 (masked).
+			 */
+			icr = REG_INT_STAT_RBNEI;
+			ctucan_write32(priv, CTUCANFD_INT_MASK_SET, icr);
+			ctucan_write32(priv, CTUCANFD_INT_STAT, icr);
+			napi_schedule(&priv->napi);
+		}
+
+		/* TXT Buffer HW Command Interrupt */
+		if (FIELD_GET(REG_INT_STAT_TXBHCI, isr)) {
+			ctucan_netdev_dbg(ndev, "TXBHCI\n");
+			/* Cleared inside */
+			ctucan_tx_interrupt(ndev);
+		}
+
+		/* Error interrupts */
+		if (FIELD_GET(REG_INT_STAT_EWLI, isr) ||
+		    FIELD_GET(REG_INT_STAT_FCSI, isr) ||
+		    FIELD_GET(REG_INT_STAT_ALI, isr)) {
+			icr = isr & (REG_INT_STAT_EWLI | REG_INT_STAT_FCSI | REG_INT_STAT_ALI);
+
+			ctucan_netdev_dbg(ndev, "some ERR interrupt: clearing 0x%08x\n", icr);
+			ctucan_write32(priv, CTUCANFD_INT_STAT, icr);
+			ctucan_err_interrupt(ndev, isr);
+		}
+		/* Ignore RI, TI, LFI, RFI, BSI */
+	}
+
+	netdev_err(ndev, "%s: stuck interrupt (isr=0x%08x), stopping\n", __func__, isr);
+
+	if (FIELD_GET(REG_INT_STAT_TXBHCI, isr)) {
+		int i;
+
+		netdev_err(ndev, "txb_head=0x%08x txb_tail=0x%08x\n",
+			   priv->txb_head, priv->txb_tail);
+		for (i = 0; i < priv->ntxbufs; i++) {
+			u32 status = ctucan_get_tx_status(priv, i);
+
+			netdev_err(ndev, "txb[%d] txb status=0x%08x\n", i, status);
+		}
+	}
+
+	imask = 0xffffffff;
+	ctucan_write32(priv, CTUCANFD_INT_ENA_CLR, imask);
+	ctucan_write32(priv, CTUCANFD_INT_MASK_SET, imask);
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * ctucan_chip_stop() - Driver stop routine
+ * @ndev:	Pointer to net_device structure
+ *
+ * This is the drivers stop routine. It will disable the
+ * interrupts and disable the controller.
+ */
+static void ctucan_chip_stop(struct net_device *ndev)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	u32 mask = 0xffffffff;
+	u32 mode;
+
+	ctucan_netdev_dbg(ndev, "%s\n", __func__);
+
+	/* Disable interrupts and disable CAN */
+	ctucan_write32(priv, CTUCANFD_INT_ENA_CLR, mask);
+	ctucan_write32(priv, CTUCANFD_INT_MASK_SET, mask);
+	mode = ctucan_read32(priv, CTUCANFD_MODE);
+	mode &= ~REG_MODE_ENA;
+	ctucan_write32(priv, CTUCANFD_MODE, mode);
+
+	priv->can.state = CAN_STATE_STOPPED;
+}
+
+/**
+ * ctucan_open() - Driver open routine
+ * @ndev:	Pointer to net_device structure
+ *
+ * This is the driver open routine.
+ * Return: 0 on success and failure value on error
+ */
+static int ctucan_open(struct net_device *ndev)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	int ret;
+
+	ctucan_netdev_dbg(ndev, "%s\n", __func__);
+
+	ret = pm_runtime_get_sync(priv->dev);
+	if (ret < 0) {
+		netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n",
+			   __func__, ret);
+		pm_runtime_put_noidle(priv->dev);
+		return ret;
+	}
+
+	ret = ctucan_reset(ndev);
+	if (ret < 0)
+		goto err_reset;
+
+	/* Common open */
+	ret = open_candev(ndev);
+	if (ret) {
+		netdev_warn(ndev, "open_candev failed!\n");
+		goto err_open;
+	}
+
+	ret = request_irq(ndev->irq, ctucan_interrupt, priv->irq_flags, ndev->name, ndev);
+	if (ret < 0) {
+		netdev_err(ndev, "irq allocation for CAN failed\n");
+		goto err_irq;
+	}
+
+	ret = ctucan_chip_start(ndev);
+	if (ret < 0) {
+		netdev_err(ndev, "ctucan_chip_start failed!\n");
+		goto err_chip_start;
+	}
+
+	netdev_info(ndev, "ctu_can_fd device registered\n");
+	can_led_event(ndev, CAN_LED_EVENT_OPEN);
+	napi_enable(&priv->napi);
+	netif_start_queue(ndev);
+
+	return 0;
+
+err_chip_start:
+	free_irq(ndev->irq, ndev);
+err_irq:
+	close_candev(ndev);
+err_open:
+err_reset:
+	pm_runtime_put(priv->dev);
+
+	return ret;
+}
+
+/**
+ * ctucan_close() - Driver close routine
+ * @ndev:	Pointer to net_device structure
+ *
+ * Return: 0 always
+ */
+static int ctucan_close(struct net_device *ndev)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+
+	ctucan_netdev_dbg(ndev, "%s\n", __func__);
+
+	netif_stop_queue(ndev);
+	napi_disable(&priv->napi);
+	ctucan_chip_stop(ndev);
+	free_irq(ndev->irq, ndev);
+	close_candev(ndev);
+
+	can_led_event(ndev, CAN_LED_EVENT_STOP);
+	pm_runtime_put(priv->dev);
+
+	return 0;
+}
+
+/**
+ * ctucan_get_berr_counter() - error counter routine
+ * @ndev:	Pointer to net_device structure
+ * @bec:	Pointer to can_berr_counter structure
+ *
+ * This is the driver error counter routine.
+ * Return: 0 on success and failure value on error
+ */
+static int ctucan_get_berr_counter(const struct net_device *ndev, struct can_berr_counter *bec)
+{
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	int ret;
+
+	ctucan_netdev_dbg(ndev, "%s\n", __func__);
+
+	ret = pm_runtime_get_sync(priv->dev);
+	if (ret < 0) {
+		netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", __func__, ret);
+		pm_runtime_put_noidle(priv->dev);
+		return ret;
+	}
+
+	ctucan_get_rec_tec(priv, bec);
+	pm_runtime_put(priv->dev);
+
+	return 0;
+}
+
+static const struct net_device_ops ctucan_netdev_ops = {
+	.ndo_open	= ctucan_open,
+	.ndo_stop	= ctucan_close,
+	.ndo_start_xmit	= ctucan_start_xmit,
+	.ndo_change_mtu	= can_change_mtu,
+};
+
+int ctucan_suspend(struct device *dev)
+{
+	struct net_device *ndev = dev_get_drvdata(dev);
+	struct ctucan_priv *priv = netdev_priv(ndev);
+
+	ctucan_netdev_dbg(ndev, "%s\n", __func__);
+
+	if (netif_running(ndev)) {
+		netif_stop_queue(ndev);
+		netif_device_detach(ndev);
+	}
+
+	priv->can.state = CAN_STATE_SLEEPING;
+
+	return 0;
+}
+EXPORT_SYMBOL(ctucan_suspend);
+
+int ctucan_resume(struct device *dev)
+{
+	struct net_device *ndev = dev_get_drvdata(dev);
+	struct ctucan_priv *priv = netdev_priv(ndev);
+
+	ctucan_netdev_dbg(ndev, "%s\n", __func__);
+
+	priv->can.state = CAN_STATE_ERROR_ACTIVE;
+
+	if (netif_running(ndev)) {
+		netif_device_attach(ndev);
+		netif_start_queue(ndev);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(ctucan_resume);
+
+int ctucan_probe_common(struct device *dev, void __iomem *addr, int irq, unsigned int ntxbufs,
+			unsigned long can_clk_rate, int pm_enable_call,
+			void (*set_drvdata_fnc)(struct device *dev, struct net_device *ndev))
+{
+	struct ctucan_priv *priv;
+	struct net_device *ndev;
+	int ret;
+
+	/* Create a CAN device instance */
+	ndev = alloc_candev(sizeof(struct ctucan_priv), ntxbufs);
+	if (!ndev)
+		return -ENOMEM;
+
+	priv = netdev_priv(ndev);
+	spin_lock_init(&priv->tx_lock);
+	INIT_LIST_HEAD(&priv->peers_on_pdev);
+	priv->ntxbufs = ntxbufs;
+	priv->dev = dev;
+	priv->can.bittiming_const = &ctu_can_fd_bit_timing_max;
+	priv->can.data_bittiming_const = &ctu_can_fd_bit_timing_data_max;
+	priv->can.do_set_mode = ctucan_do_set_mode;
+
+	/* Needed for timing adjustment to be performed as soon as possible */
+	priv->can.do_set_bittiming = ctucan_set_bittiming;
+	priv->can.do_set_data_bittiming = ctucan_set_data_bittiming;
+
+	priv->can.do_get_berr_counter = ctucan_get_berr_counter;
+	priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK
+					| CAN_CTRLMODE_LISTENONLY
+					| CAN_CTRLMODE_FD
+					| CAN_CTRLMODE_PRESUME_ACK
+					| CAN_CTRLMODE_BERR_REPORTING
+					| CAN_CTRLMODE_FD_NON_ISO
+					| CAN_CTRLMODE_ONE_SHOT;
+	priv->mem_base = addr;
+
+	/* Get IRQ for the device */
+	ndev->irq = irq;
+	ndev->flags |= IFF_ECHO;	/* We support local echo */
+
+	if (set_drvdata_fnc)
+		set_drvdata_fnc(dev, ndev);
+	SET_NETDEV_DEV(ndev, dev);
+	ndev->netdev_ops = &ctucan_netdev_ops;
+
+	/* Getting the can_clk info */
+	if (!can_clk_rate) {
+		priv->can_clk = devm_clk_get(dev, NULL);
+		if (IS_ERR(priv->can_clk)) {
+			dev_err(dev, "Device clock not found.\n");
+			ret = PTR_ERR(priv->can_clk);
+			goto err_free;
+		}
+		can_clk_rate = clk_get_rate(priv->can_clk);
+	}
+
+	priv->write_reg = ctucan_write32_le;
+	priv->read_reg = ctucan_read32_le;
+
+	if (pm_enable_call)
+		pm_runtime_enable(dev);
+	ret = pm_runtime_get_sync(dev);
+	if (ret < 0) {
+		netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n",
+			   __func__, ret);
+		pm_runtime_put_noidle(priv->dev);
+		goto err_pmdisable;
+	}
+
+	/* Check for big-endianity and set according IO-accessors */
+	if ((ctucan_read32(priv, CTUCANFD_DEVICE_ID) & 0xFFFF) != CTUCANFD_ID) {
+		priv->write_reg = ctucan_write32_be;
+		priv->read_reg = ctucan_read32_be;
+		if ((ctucan_read32(priv, CTUCANFD_DEVICE_ID) & 0xFFFF) != CTUCANFD_ID) {
+			netdev_err(ndev, "CTU_CAN_FD signature not found\n");
+			ret = -ENODEV;
+			goto err_deviceoff;
+		}
+	}
+
+	ret = ctucan_reset(ndev);
+	if (ret < 0)
+		goto err_deviceoff;
+
+	priv->can.clock.freq = can_clk_rate;
+
+	netif_napi_add(ndev, &priv->napi, ctucan_rx_poll, NAPI_POLL_WEIGHT);
+
+	ret = register_candev(ndev);
+	if (ret) {
+		dev_err(dev, "fail to register failed (err=%d)\n", ret);
+		goto err_deviceoff;
+	}
+
+	devm_can_led_init(ndev);
+
+	pm_runtime_put(dev);
+
+	netdev_dbg(ndev, "mem_base=0x%p irq=%d clock=%d, no. of txt buffers:%d\n",
+		   priv->mem_base, ndev->irq, priv->can.clock.freq, priv->ntxbufs);
+
+	return 0;
+
+err_deviceoff:
+	pm_runtime_put(priv->dev);
+err_pmdisable:
+	if (pm_enable_call)
+		pm_runtime_disable(dev);
+err_free:
+	list_del_init(&priv->peers_on_pdev);
+	free_candev(ndev);
+	return ret;
+}
+EXPORT_SYMBOL(ctucan_probe_common);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Martin Jerabek <martin.jerabek01@gmail.com>");
+MODULE_AUTHOR("Pavel Pisa <pisa@cmp.felk.cvut.cz>");
+MODULE_AUTHOR("Ondrej Ille <ondrej.ille@gmail.com>");
+MODULE_DESCRIPTION("CTU CAN FD interface");

drivers/net/can/ctucanfd/ctucanfd_kframe.h

+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*******************************************************************************
+ *
+ * CTU CAN FD IP Core
+ *
+ * Copyright (C) 2015-2018 Ondrej Ille <ondrej.ille@gmail.com> FEE CTU
+ * Copyright (C) 2018-2021 Ondrej Ille <ondrej.ille@gmail.com> self-funded
+ * Copyright (C) 2018-2019 Martin Jerabek <martin.jerabek01@gmail.com> FEE CTU
+ * Copyright (C) 2018-2021 Pavel Pisa <pisa@cmp.felk.cvut.cz> FEE CTU/self-funded
+ *
+ * Project advisors:
+ *     Jiri Novak <jnovak@fel.cvut.cz>
+ *     Pavel Pisa <pisa@cmp.felk.cvut.cz>
+ *
+ * Department of Measurement         (http://meas.fel.cvut.cz/)
+ * Faculty of Electrical Engineering (http://www.fel.cvut.cz)
+ * Czech Technical University        (http://www.cvut.cz/)
+ ******************************************************************************/
+
+/* This file is autogenerated, DO NOT EDIT! */
+
+#ifndef __CTU_CAN_FD_CAN_FD_FRAME_FORMAT__
+#define __CTU_CAN_FD_CAN_FD_FRAME_FORMAT__
+
+#include <linux/bits.h>
+
+/* CAN_Frame_format memory map */
+enum ctu_can_fd_can_frame_format {
+	CTUCANFD_FRAME_FORMAT_W       = 0x0,
+	CTUCANFD_IDENTIFIER_W         = 0x4,
+	CTUCANFD_TIMESTAMP_L_W        = 0x8,
+	CTUCANFD_TIMESTAMP_U_W        = 0xc,
+	CTUCANFD_DATA_1_4_W          = 0x10,
+	CTUCANFD_DATA_5_8_W          = 0x14,
+	CTUCANFD_DATA_61_64_W        = 0x4c,
+};
+
+/* CAN_FD_Frame_format memory region */
+
+/*  FRAME_FORMAT_W registers */
+#define REG_FRAME_FORMAT_W_DLC GENMASK(3, 0)
+#define REG_FRAME_FORMAT_W_RTR BIT(5)
+#define REG_FRAME_FORMAT_W_IDE BIT(6)
+#define REG_FRAME_FORMAT_W_FDF BIT(7)
+#define REG_FRAME_FORMAT_W_BRS BIT(9)
+#define REG_FRAME_FORMAT_W_ESI_RSV BIT(10)
+#define REG_FRAME_FORMAT_W_RWCNT GENMASK(15, 11)
+
+/*  IDENTIFIER_W registers */
+#define REG_IDENTIFIER_W_IDENTIFIER_EXT GENMASK(17, 0)
+#define REG_IDENTIFIER_W_IDENTIFIER_BASE GENMASK(28, 18)
+
+/*  TIMESTAMP_L_W registers */
+#define REG_TIMESTAMP_L_W_TIME_STAMP_L_W GENMASK(31, 0)
+
+/*  TIMESTAMP_U_W registers */
+#define REG_TIMESTAMP_U_W_TIMESTAMP_U_W GENMASK(31, 0)
+
+/*  DATA_1_4_W registers */
+#define REG_DATA_1_4_W_DATA_1 GENMASK(7, 0)
+#define REG_DATA_1_4_W_DATA_2 GENMASK(15, 8)
+#define REG_DATA_1_4_W_DATA_3 GENMASK(23, 16)
+#define REG_DATA_1_4_W_DATA_4 GENMASK(31, 24)
+
+/*  DATA_5_8_W registers */
+#define REG_DATA_5_8_W_DATA_5 GENMASK(7, 0)
+#define REG_DATA_5_8_W_DATA_6 GENMASK(15, 8)
+#define REG_DATA_5_8_W_DATA_7 GENMASK(23, 16)
+#define REG_DATA_5_8_W_DATA_8 GENMASK(31, 24)
+
+/*  DATA_61_64_W registers */
+#define REG_DATA_61_64_W_DATA_61 GENMASK(7, 0)
+#define REG_DATA_61_64_W_DATA_62 GENMASK(15, 8)
+#define REG_DATA_61_64_W_DATA_63 GENMASK(23, 16)
+#define REG_DATA_61_64_W_DATA_64 GENMASK(31, 24)
+
+#endif

drivers/net/can/ctucanfd/ctucanfd_kregs.h

+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*******************************************************************************
+ *
+ * CTU CAN FD IP Core
+ *
+ * Copyright (C) 2015-2018 Ondrej Ille <ondrej.ille@gmail.com> FEE CTU
+ * Copyright (C) 2018-2021 Ondrej Ille <ondrej.ille@gmail.com> self-funded
+ * Copyright (C) 2018-2019 Martin Jerabek <martin.jerabek01@gmail.com> FEE CTU
+ * Copyright (C) 2018-2021 Pavel Pisa <pisa@cmp.felk.cvut.cz> FEE CTU/self-funded
+ *
+ * Project advisors:
+ *     Jiri Novak <jnovak@fel.cvut.cz>
+ *     Pavel Pisa <pisa@cmp.felk.cvut.cz>
+ *
+ * Department of Measurement         (http://meas.fel.cvut.cz/)
+ * Faculty of Electrical Engineering (http://www.fel.cvut.cz)
+ * Czech Technical University        (http://www.cvut.cz/)
+ ******************************************************************************/
+
+/* This file is autogenerated, DO NOT EDIT! */
+
+#ifndef __CTU_CAN_FD_CAN_FD_REGISTER_MAP__
+#define __CTU_CAN_FD_CAN_FD_REGISTER_MAP__
+
+#include <linux/bits.h>
+
+/* CAN_Registers memory map */
+enum ctu_can_fd_can_registers {
+	CTUCANFD_DEVICE_ID             = 0x0,
+	CTUCANFD_VERSION               = 0x2,
+	CTUCANFD_MODE                  = 0x4,
+	CTUCANFD_SETTINGS              = 0x6,
+	CTUCANFD_STATUS                = 0x8,
+	CTUCANFD_COMMAND               = 0xc,
+	CTUCANFD_INT_STAT             = 0x10,
+	CTUCANFD_INT_ENA_SET          = 0x14,
+	CTUCANFD_INT_ENA_CLR          = 0x18,
+	CTUCANFD_INT_MASK_SET         = 0x1c,
+	CTUCANFD_INT_MASK_CLR         = 0x20,
+	CTUCANFD_BTR                  = 0x24,
+	CTUCANFD_BTR_FD               = 0x28,
+	CTUCANFD_EWL                  = 0x2c,
+	CTUCANFD_ERP                  = 0x2d,
+	CTUCANFD_FAULT_STATE          = 0x2e,
+	CTUCANFD_REC                  = 0x30,
+	CTUCANFD_TEC                  = 0x32,
+	CTUCANFD_ERR_NORM             = 0x34,
+	CTUCANFD_ERR_FD               = 0x36,
+	CTUCANFD_CTR_PRES             = 0x38,
+	CTUCANFD_FILTER_A_MASK        = 0x3c,
+	CTUCANFD_FILTER_A_VAL         = 0x40,
+	CTUCANFD_FILTER_B_MASK        = 0x44,
+	CTUCANFD_FILTER_B_VAL         = 0x48,
+	CTUCANFD_FILTER_C_MASK        = 0x4c,
+	CTUCANFD_FILTER_C_VAL         = 0x50,
+	CTUCANFD_FILTER_RAN_LOW       = 0x54,
+	CTUCANFD_FILTER_RAN_HIGH      = 0x58,
+	CTUCANFD_FILTER_CONTROL       = 0x5c,
+	CTUCANFD_FILTER_STATUS        = 0x5e,
+	CTUCANFD_RX_MEM_INFO          = 0x60,
+	CTUCANFD_RX_POINTERS          = 0x64,
+	CTUCANFD_RX_STATUS            = 0x68,
+	CTUCANFD_RX_SETTINGS          = 0x6a,
+	CTUCANFD_RX_DATA              = 0x6c,
+	CTUCANFD_TX_STATUS            = 0x70,
+	CTUCANFD_TX_COMMAND           = 0x74,
+	CTUCANFD_TX_PRIORITY          = 0x78,
+	CTUCANFD_ERR_CAPT             = 0x7c,
+	CTUCANFD_ALC                  = 0x7e,
+	CTUCANFD_TRV_DELAY            = 0x80,
+	CTUCANFD_SSP_CFG              = 0x82,
+	CTUCANFD_RX_FR_CTR            = 0x84,
+	CTUCANFD_TX_FR_CTR            = 0x88,
+	CTUCANFD_DEBUG_REGISTER       = 0x8c,
+	CTUCANFD_YOLO_REG             = 0x90,
+	CTUCANFD_TIMESTAMP_LOW        = 0x94,
+	CTUCANFD_TIMESTAMP_HIGH       = 0x98,
+	CTUCANFD_TXTB1_DATA_1        = 0x100,
+	CTUCANFD_TXTB1_DATA_2        = 0x104,
+	CTUCANFD_TXTB1_DATA_20       = 0x14c,
+	CTUCANFD_TXTB2_DATA_1        = 0x200,
+	CTUCANFD_TXTB2_DATA_2        = 0x204,
+	CTUCANFD_TXTB2_DATA_20       = 0x24c,
+	CTUCANFD_TXTB3_DATA_1        = 0x300,
+	CTUCANFD_TXTB3_DATA_2        = 0x304,
+	CTUCANFD_TXTB3_DATA_20       = 0x34c,
+	CTUCANFD_TXTB4_DATA_1        = 0x400,
+	CTUCANFD_TXTB4_DATA_2        = 0x404,
+	CTUCANFD_TXTB4_DATA_20       = 0x44c,
+};
+
+/* Control_registers memory region */
+
+/*  DEVICE_ID VERSION registers */
+#define REG_DEVICE_ID_DEVICE_ID GENMASK(15, 0)
+#define REG_DEVICE_ID_VER_MINOR GENMASK(23, 16)
+#define REG_DEVICE_ID_VER_MAJOR GENMASK(31, 24)
+
+/*  MODE SETTINGS registers */
+#define REG_MODE_RST BIT(0)
+#define REG_MODE_BMM BIT(1)
+#define REG_MODE_STM BIT(2)
+#define REG_MODE_AFM BIT(3)
+#define REG_MODE_FDE BIT(4)
+#define REG_MODE_ACF BIT(7)
+#define REG_MODE_TSTM BIT(8)
+#define REG_MODE_RTRLE BIT(16)
+#define REG_MODE_RTRTH GENMASK(20, 17)
+#define REG_MODE_ILBP BIT(21)
+#define REG_MODE_ENA BIT(22)
+#define REG_MODE_NISOFD BIT(23)
+#define REG_MODE_PEX BIT(24)
+#define REG_MODE_TBFBO BIT(25)
+#define REG_MODE_FDRF BIT(26)
+
+/*  STATUS registers */
+#define REG_STATUS_RXNE BIT(0)
+#define REG_STATUS_DOR BIT(1)
+#define REG_STATUS_TXNF BIT(2)
+#define REG_STATUS_EFT BIT(3)
+#define REG_STATUS_RXS BIT(4)
+#define REG_STATUS_TXS BIT(5)
+#define REG_STATUS_EWL BIT(6)
+#define REG_STATUS_IDLE BIT(7)
+#define REG_STATUS_PEXS BIT(8)
+
+/*  COMMAND registers */
+#define REG_COMMAND_RRB BIT(2)
+#define REG_COMMAND_CDO BIT(3)
+#define REG_COMMAND_ERCRST BIT(4)
+#define REG_COMMAND_RXFCRST BIT(5)
+#define REG_COMMAND_TXFCRST BIT(6)
+#define REG_COMMAND_CPEXS BIT(7)
+
+/*  INT_STAT registers */
+#define REG_INT_STAT_RXI BIT(0)
+#define REG_INT_STAT_TXI BIT(1)
+#define REG_INT_STAT_EWLI BIT(2)
+#define REG_INT_STAT_DOI BIT(3)
+#define REG_INT_STAT_FCSI BIT(4)
+#define REG_INT_STAT_ALI BIT(5)
+#define REG_INT_STAT_BEI BIT(6)
+#define REG_INT_STAT_OFI BIT(7)
+#define REG_INT_STAT_RXFI BIT(8)
+#define REG_INT_STAT_BSI BIT(9)
+#define REG_INT_STAT_RBNEI BIT(10)
+#define REG_INT_STAT_TXBHCI BIT(11)
+
+/*  INT_ENA_SET registers */
+#define REG_INT_ENA_SET_INT_ENA_SET GENMASK(11, 0)
+
+/*  INT_ENA_CLR registers */
+#define REG_INT_ENA_CLR_INT_ENA_CLR GENMASK(11, 0)
+
+/*  INT_MASK_SET registers */
+#define REG_INT_MASK_SET_INT_MASK_SET GENMASK(11, 0)
+
+/*  INT_MASK_CLR registers */
+#define REG_INT_MASK_CLR_INT_MASK_CLR GENMASK(11, 0)
+
+/*  BTR registers */
+#define REG_BTR_PROP GENMASK(6, 0)
+#define REG_BTR_PH1 GENMASK(12, 7)
+#define REG_BTR_PH2 GENMASK(18, 13)
+#define REG_BTR_BRP GENMASK(26, 19)
+#define REG_BTR_SJW GENMASK(31, 27)
+
+/*  BTR_FD registers */
+#define REG_BTR_FD_PROP_FD GENMASK(5, 0)
+#define REG_BTR_FD_PH1_FD GENMASK(11, 7)
+#define REG_BTR_FD_PH2_FD GENMASK(17, 13)
+#define REG_BTR_FD_BRP_FD GENMASK(26, 19)
+#define REG_BTR_FD_SJW_FD GENMASK(31, 27)
+
+/*  EWL ERP FAULT_STATE registers */
+#define REG_EWL_EW_LIMIT GENMASK(7, 0)
+#define REG_EWL_ERP_LIMIT GENMASK(15, 8)
+#define REG_EWL_ERA BIT(16)
+#define REG_EWL_ERP BIT(17)
+#define REG_EWL_BOF BIT(18)
+
+/*  REC TEC registers */
+#define REG_REC_REC_VAL GENMASK(8, 0)
+#define REG_REC_TEC_VAL GENMASK(24, 16)
+
+/*  ERR_NORM ERR_FD registers */
+#define REG_ERR_NORM_ERR_NORM_VAL GENMASK(15, 0)
+#define REG_ERR_NORM_ERR_FD_VAL GENMASK(31, 16)
+
+/*  CTR_PRES registers */
+#define REG_CTR_PRES_CTPV GENMASK(8, 0)
+#define REG_CTR_PRES_PTX BIT(9)
+#define REG_CTR_PRES_PRX BIT(10)
+#define REG_CTR_PRES_ENORM BIT(11)
+#define REG_CTR_PRES_EFD BIT(12)
+
+/*  FILTER_A_MASK registers */
+#define REG_FILTER_A_MASK_BIT_MASK_A_VAL GENMASK(28, 0)
+
+/*  FILTER_A_VAL registers */
+#define REG_FILTER_A_VAL_BIT_VAL_A_VAL GENMASK(28, 0)
+
+/*  FILTER_B_MASK registers */
+#define REG_FILTER_B_MASK_BIT_MASK_B_VAL GENMASK(28, 0)
+
+/*  FILTER_B_VAL registers */
+#define REG_FILTER_B_VAL_BIT_VAL_B_VAL GENMASK(28, 0)
+
+/*  FILTER_C_MASK registers */
+#define REG_FILTER_C_MASK_BIT_MASK_C_VAL GENMASK(28, 0)
+
+/*  FILTER_C_VAL registers */
+#define REG_FILTER_C_VAL_BIT_VAL_C_VAL GENMASK(28, 0)
+
+/*  FILTER_RAN_LOW registers */
+#define REG_FILTER_RAN_LOW_BIT_RAN_LOW_VAL GENMASK(28, 0)
+
+/*  FILTER_RAN_HIGH registers */
+#define REG_FILTER_RAN_HIGH_BIT_RAN_HIGH_VAL GENMASK(28, 0)
+
+/*  FILTER_CONTROL FILTER_STATUS registers */
+#define REG_FILTER_CONTROL_FANB BIT(0)
+#define REG_FILTER_CONTROL_FANE BIT(1)
+#define REG_FILTER_CONTROL_FAFB BIT(2)
+#define REG_FILTER_CONTROL_FAFE BIT(3)
+#define REG_FILTER_CONTROL_FBNB BIT(4)
+#define REG_FILTER_CONTROL_FBNE BIT(5)
+#define REG_FILTER_CONTROL_FBFB BIT(6)
+#define REG_FILTER_CONTROL_FBFE BIT(7)
+#define REG_FILTER_CONTROL_FCNB BIT(8)
+#define REG_FILTER_CONTROL_FCNE BIT(9)
+#define REG_FILTER_CONTROL_FCFB BIT(10)
+#define REG_FILTER_CONTROL_FCFE BIT(11)
+#define REG_FILTER_CONTROL_FRNB BIT(12)
+#define REG_FILTER_CONTROL_FRNE BIT(13)
+#define REG_FILTER_CONTROL_FRFB BIT(14)
+#define REG_FILTER_CONTROL_FRFE BIT(15)
+#define REG_FILTER_CONTROL_SFA BIT(16)
+#define REG_FILTER_CONTROL_SFB BIT(17)
+#define REG_FILTER_CONTROL_SFC BIT(18)
+#define REG_FILTER_CONTROL_SFR BIT(19)
+
+/*  RX_MEM_INFO registers */
+#define REG_RX_MEM_INFO_RX_BUFF_SIZE GENMASK(12, 0)
+#define REG_RX_MEM_INFO_RX_MEM_FREE GENMASK(28, 16)
+
+/*  RX_POINTERS registers */
+#define REG_RX_POINTERS_RX_WPP GENMASK(11, 0)
+#define REG_RX_POINTERS_RX_RPP GENMASK(27, 16)
+
+/*  RX_STATUS RX_SETTINGS registers */
+#define REG_RX_STATUS_RXE BIT(0)
+#define REG_RX_STATUS_RXF BIT(1)
+#define REG_RX_STATUS_RXMOF BIT(2)
+#define REG_RX_STATUS_RXFRC GENMASK(14, 4)
+#define REG_RX_STATUS_RTSOP BIT(16)
+
+/*  RX_DATA registers */
+#define REG_RX_DATA_RX_DATA GENMASK(31, 0)
+
+/*  TX_STATUS registers */
+#define REG_TX_STATUS_TX1S GENMASK(3, 0)
+#define REG_TX_STATUS_TX2S GENMASK(7, 4)
+#define REG_TX_STATUS_TX3S GENMASK(11, 8)
+#define REG_TX_STATUS_TX4S GENMASK(15, 12)
+
+/*  TX_COMMAND registers */
+#define REG_TX_COMMAND_TXCE BIT(0)
+#define REG_TX_COMMAND_TXCR BIT(1)
+#define REG_TX_COMMAND_TXCA BIT(2)
+#define REG_TX_COMMAND_TXB1 BIT(8)
+#define REG_TX_COMMAND_TXB2 BIT(9)
+#define REG_TX_COMMAND_TXB3 BIT(10)
+#define REG_TX_COMMAND_TXB4 BIT(11)
+
+/*  TX_PRIORITY registers */
+#define REG_TX_PRIORITY_TXT1P GENMASK(2, 0)
+#define REG_TX_PRIORITY_TXT2P GENMASK(6, 4)
+#define REG_TX_PRIORITY_TXT3P GENMASK(10, 8)
+#define REG_TX_PRIORITY_TXT4P GENMASK(14, 12)
+
+/*  ERR_CAPT ALC registers */
+#define REG_ERR_CAPT_ERR_POS GENMASK(4, 0)
+#define REG_ERR_CAPT_ERR_TYPE GENMASK(7, 5)
+#define REG_ERR_CAPT_ALC_BIT GENMASK(20, 16)
+#define REG_ERR_CAPT_ALC_ID_FIELD GENMASK(23, 21)
+
+/*  TRV_DELAY SSP_CFG registers */
+#define REG_TRV_DELAY_TRV_DELAY_VALUE GENMASK(6, 0)
+#define REG_TRV_DELAY_SSP_OFFSET GENMASK(23, 16)
+#define REG_TRV_DELAY_SSP_SRC GENMASK(25, 24)
+
+/*  RX_FR_CTR registers */
+#define REG_RX_FR_CTR_RX_FR_CTR_VAL GENMASK(31, 0)
+
+/*  TX_FR_CTR registers */
+#define REG_TX_FR_CTR_TX_FR_CTR_VAL GENMASK(31, 0)
+
+/*  DEBUG_REGISTER registers */
+#define REG_DEBUG_REGISTER_STUFF_COUNT GENMASK(2, 0)
+#define REG_DEBUG_REGISTER_DESTUFF_COUNT GENMASK(5, 3)
+#define REG_DEBUG_REGISTER_PC_ARB BIT(6)
+#define REG_DEBUG_REGISTER_PC_CON BIT(7)
+#define REG_DEBUG_REGISTER_PC_DAT BIT(8)
+#define REG_DEBUG_REGISTER_PC_STC BIT(9)
+#define REG_DEBUG_REGISTER_PC_CRC BIT(10)
+#define REG_DEBUG_REGISTER_PC_CRCD BIT(11)
+#define REG_DEBUG_REGISTER_PC_ACK BIT(12)
+#define REG_DEBUG_REGISTER_PC_ACKD BIT(13)
+#define REG_DEBUG_REGISTER_PC_EOF BIT(14)
+#define REG_DEBUG_REGISTER_PC_INT BIT(15)
+#define REG_DEBUG_REGISTER_PC_SUSP BIT(16)
+#define REG_DEBUG_REGISTER_PC_OVR BIT(17)
+#define REG_DEBUG_REGISTER_PC_SOF BIT(18)
+
+/*  YOLO_REG registers */
+#define REG_YOLO_REG_YOLO_VAL GENMASK(31, 0)
+
+/*  TIMESTAMP_LOW registers */
+#define REG_TIMESTAMP_LOW_TIMESTAMP_LOW GENMASK(31, 0)
+
+/*  TIMESTAMP_HIGH registers */
+#define REG_TIMESTAMP_HIGH_TIMESTAMP_HIGH GENMASK(31, 0)
+
+#endif

drivers/net/can/ctucanfd/ctucanfd_pci.c

+// SPDX-License-Identifier: GPL-2.0-or-later
+/*******************************************************************************
+ *
+ * CTU CAN FD IP Core
+ *
+ * Copyright (C) 2015-2018 Ondrej Ille <ondrej.ille@gmail.com> FEE CTU
+ * Copyright (C) 2018-2021 Ondrej Ille <ondrej.ille@gmail.com> self-funded
+ * Copyright (C) 2018-2019 Martin Jerabek <martin.jerabek01@gmail.com> FEE CTU
+ * Copyright (C) 2018-2022 Pavel Pisa <pisa@cmp.felk.cvut.cz> FEE CTU/self-funded
+ *
+ * Project advisors:
+ *     Jiri Novak <jnovak@fel.cvut.cz>
+ *     Pavel Pisa <pisa@cmp.felk.cvut.cz>
+ *
+ * Department of Measurement         (http://meas.fel.cvut.cz/)
+ * Faculty of Electrical Engineering (http://www.fel.cvut.cz)
+ * Czech Technical University        (http://www.cvut.cz/)
+ ******************************************************************************/
+
+#include <linux/module.h>
+#include <linux/pci.h>
+
+#include "ctucanfd.h"
+
+#ifndef PCI_DEVICE_DATA
+#define PCI_DEVICE_DATA(vend, dev, data) \
+.vendor = PCI_VENDOR_ID_##vend, \
+.device = PCI_DEVICE_ID_##vend##_##dev, \
+.subvendor = PCI_ANY_ID, .subdevice = PCI_ANY_ID, 0, 0, \
+.driver_data = (kernel_ulong_t)(data)
+#endif
+
+#ifndef PCI_VENDOR_ID_TEDIA
+#define PCI_VENDOR_ID_TEDIA 0x1760
+#endif
+
+#ifndef PCI_DEVICE_ID_TEDIA_CTUCAN_VER21
+#define PCI_DEVICE_ID_TEDIA_CTUCAN_VER21 0xff00
+#endif
+
+#define CTUCAN_BAR0_CTUCAN_ID 0x0000
+#define CTUCAN_BAR0_CRA_BASE  0x4000
+#define CYCLONE_IV_CRA_A2P_IE (0x0050)
+
+#define CTUCAN_WITHOUT_CTUCAN_ID  0
+#define CTUCAN_WITH_CTUCAN_ID     1
+
+static bool use_msi = true;
+module_param(use_msi, bool, 0444);
+MODULE_PARM_DESC(use_msi, "PCIe implementation use MSI interrupts. Default: 1 (yes)");
+
+static bool pci_use_second = true;
+module_param(pci_use_second, bool, 0444);
+MODULE_PARM_DESC(pci_use_second, "Use the second CAN core on PCIe card. Default: 1 (yes)");
+
+struct ctucan_pci_board_data {
+	void __iomem *bar0_base;
+	void __iomem *cra_base;
+	void __iomem *bar1_base;
+	struct list_head ndev_list_head;
+	int use_msi;
+};
+
+static struct ctucan_pci_board_data *ctucan_pci_get_bdata(struct pci_dev *pdev)
+{
+	return (struct ctucan_pci_board_data *)pci_get_drvdata(pdev);
+}
+
+static void ctucan_pci_set_drvdata(struct device *dev,
+				   struct net_device *ndev)
+{
+	struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
+	struct ctucan_priv *priv = netdev_priv(ndev);
+	struct ctucan_pci_board_data *bdata = ctucan_pci_get_bdata(pdev);
+
+	list_add(&priv->peers_on_pdev, &bdata->ndev_list_head);
+	priv->irq_flags = IRQF_SHARED;
+}
+
+/**
+ * ctucan_pci_probe - PCI registration call
+ * @pdev:	Handle to the pci device structure
+ * @ent:	Pointer to the entry from ctucan_pci_tbl
+ *
+ * This function does all the memory allocation and registration for the CAN
+ * device.
+ *
+ * Return: 0 on success and failure value on error
+ */
+static int ctucan_pci_probe(struct pci_dev *pdev,
+			    const struct pci_device_id *ent)
+{
+	struct device	*dev = &pdev->dev;
+	unsigned long driver_data = ent->driver_data;
+	struct ctucan_pci_board_data *bdata;
+	void __iomem *addr;
+	void __iomem *cra_addr;
+	void __iomem *bar0_base;
+	u32 cra_a2p_ie;
+	u32 ctucan_id = 0;
+	int ret;
+	unsigned int ntxbufs;
+	unsigned int num_cores = 1;
+	unsigned int core_i = 0;
+	int irq;
+	int msi_ok = 0;
+
+	ret = pci_enable_device(pdev);
+	if (ret) {
+		dev_err(dev, "pci_enable_device FAILED\n");
+		goto err;
+	}
+
+	ret = pci_request_regions(pdev, KBUILD_MODNAME);
+	if (ret) {
+		dev_err(dev, "pci_request_regions FAILED\n");
+		goto err_disable_device;
+	}
+
+	if (use_msi) {
+		ret = pci_enable_msi(pdev);
+		if (!ret) {
+			dev_info(dev, "MSI enabled\n");
+			pci_set_master(pdev);
+			msi_ok = 1;
+		}
+	}
+
+	dev_info(dev, "ctucan BAR0 0x%08llx 0x%08llx\n",
+		 (long long)pci_resource_start(pdev, 0),
+		 (long long)pci_resource_len(pdev, 0));
+
+	dev_info(dev, "ctucan BAR1 0x%08llx 0x%08llx\n",
+		 (long long)pci_resource_start(pdev, 1),
+		 (long long)pci_resource_len(pdev, 1));
+
+	addr = pci_iomap(pdev, 1, pci_resource_len(pdev, 1));
+	if (!addr) {
+		dev_err(dev, "PCI BAR 1 cannot be mapped\n");
+		ret = -ENOMEM;
+		goto err_release_regions;
+	}
+
+	/* Cyclone IV PCI Express Control Registers Area */
+	bar0_base = pci_iomap(pdev, 0, pci_resource_len(pdev, 0));
+	if (!bar0_base) {
+		dev_err(dev, "PCI BAR 0 cannot be mapped\n");
+		ret = -EIO;
+		goto err_pci_iounmap_bar1;
+	}
+
+	if (driver_data == CTUCAN_WITHOUT_CTUCAN_ID) {
+		cra_addr = bar0_base;
+		num_cores = 2;
+	} else {
+		cra_addr = bar0_base + CTUCAN_BAR0_CRA_BASE;
+		ctucan_id = ioread32(bar0_base + CTUCAN_BAR0_CTUCAN_ID);
+		dev_info(dev, "ctucan_id 0x%08lx\n", (unsigned long)ctucan_id);
+		num_cores = ctucan_id & 0xf;
+	}
+
+	irq = pdev->irq;
+
+	ntxbufs = 4;
+
+	bdata = kzalloc(sizeof(*bdata), GFP_KERNEL);
+	if (!bdata) {
+		ret = -ENOMEM;
+		goto err_pci_iounmap_bar0;
+	}
+
+	INIT_LIST_HEAD(&bdata->ndev_list_head);
+	bdata->bar0_base = bar0_base;
+	bdata->cra_base = cra_addr;
+	bdata->bar1_base = addr;
+	bdata->use_msi = msi_ok;
+
+	pci_set_drvdata(pdev, bdata);
+
+	ret = ctucan_probe_common(dev, addr, irq, ntxbufs, 100000000,
+				  0, ctucan_pci_set_drvdata);
+	if (ret < 0)
+		goto err_free_board;
+
+	core_i++;
+
+	while (pci_use_second && (core_i < num_cores)) {
+		addr += 0x4000;
+		ret = ctucan_probe_common(dev, addr, irq, ntxbufs, 100000000,
+					  0, ctucan_pci_set_drvdata);
+		if (ret < 0) {
+			dev_info(dev, "CTU CAN FD core %d initialization failed\n",
+				 core_i);
+			break;
+		}
+		core_i++;
+	}
+
+	/* enable interrupt in
+	 * Avalon-MM to PCI Express Interrupt Enable Register
+	 */
+	cra_a2p_ie = ioread32(cra_addr + CYCLONE_IV_CRA_A2P_IE);
+	dev_info(dev, "cra_a2p_ie 0x%08x\n", cra_a2p_ie);
+	cra_a2p_ie |= 1;
+	iowrite32(cra_a2p_ie, cra_addr + CYCLONE_IV_CRA_A2P_IE);
+	cra_a2p_ie = ioread32(cra_addr + CYCLONE_IV_CRA_A2P_IE);
+	dev_info(dev, "cra_a2p_ie 0x%08x\n", cra_a2p_ie);
+
+	return 0;
+
+err_free_board:
+	pci_set_drvdata(pdev, NULL);
+	kfree(bdata);
+err_pci_iounmap_bar0:
+	pci_iounmap(pdev, cra_addr);
+err_pci_iounmap_bar1:
+	pci_iounmap(pdev, addr);
+err_release_regions:
+	if (msi_ok) {
+		pci_disable_msi(pdev);
+		pci_clear_master(pdev);
+	}
+	pci_release_regions(pdev);
+err_disable_device:
+	pci_disable_device(pdev);
+err:
+	return ret;
+}
+
+/**
+ * ctucan_pci_remove - Unregister the device after releasing the resources
+ * @pdev:	Handle to the pci device structure
+ *
+ * This function frees all the resources allocated to the device.
+ * Return: 0 always
+ */
+static void ctucan_pci_remove(struct pci_dev *pdev)
+{
+	struct net_device *ndev;
+	struct ctucan_priv *priv = NULL;
+	struct ctucan_pci_board_data *bdata = ctucan_pci_get_bdata(pdev);
+
+	dev_dbg(&pdev->dev, "ctucan_remove");
+
+	if (!bdata) {
+		dev_err(&pdev->dev, "%s: no list of devices\n", __func__);
+		return;
+	}
+
+	/* disable interrupt in
+	 * Avalon-MM to PCI Express Interrupt Enable Register
+	 */
+	if (bdata->cra_base)
+		iowrite32(0, bdata->cra_base + CYCLONE_IV_CRA_A2P_IE);
+
+	while ((priv = list_first_entry_or_null(&bdata->ndev_list_head, struct ctucan_priv,
+						peers_on_pdev)) != NULL) {
+		ndev = priv->can.dev;
+
+		unregister_candev(ndev);
+
+		netif_napi_del(&priv->napi);
+
+		list_del_init(&priv->peers_on_pdev);
+		free_candev(ndev);
+	}
+
+	pci_iounmap(pdev, bdata->bar1_base);
+
+	if (bdata->use_msi) {
+		pci_disable_msi(pdev);
+		pci_clear_master(pdev);
+	}
+
+	pci_release_regions(pdev);
+	pci_disable_device(pdev);
+
+	pci_iounmap(pdev, bdata->bar0_base);
+
+	pci_set_drvdata(pdev, NULL);
+	kfree(bdata);
+}
+
+static SIMPLE_DEV_PM_OPS(ctucan_pci_pm_ops, ctucan_suspend, ctucan_resume);
+
+static const struct pci_device_id ctucan_pci_tbl[] = {
+	{PCI_DEVICE_DATA(TEDIA, CTUCAN_VER21,
+		CTUCAN_WITH_CTUCAN_ID)},
+	{},
+};
+
+static struct pci_driver ctucan_pci_driver = {
+	.name = KBUILD_MODNAME,
+	.id_table = ctucan_pci_tbl,
+	.probe = ctucan_pci_probe,
+	.remove = ctucan_pci_remove,
+	.driver.pm = &ctucan_pci_pm_ops,
+};
+
+module_pci_driver(ctucan_pci_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Pavel Pisa <pisa@cmp.felk.cvut.cz>");
+MODULE_DESCRIPTION("CTU CAN FD for PCI bus");

drivers/net/can/ctucanfd/ctucanfd_platform.c

+// SPDX-License-Identifier: GPL-2.0-or-later
+/*******************************************************************************
+ *
+ * CTU CAN FD IP Core
+ *
+ * Copyright (C) 2015-2018 Ondrej Ille <ondrej.ille@gmail.com> FEE CTU
+ * Copyright (C) 2018-2021 Ondrej Ille <ondrej.ille@gmail.com> self-funded
+ * Copyright (C) 2018-2019 Martin Jerabek <martin.jerabek01@gmail.com> FEE CTU
+ * Copyright (C) 2018-2022 Pavel Pisa <pisa@cmp.felk.cvut.cz> FEE CTU/self-funded
+ *
+ * Project advisors:
+ *     Jiri Novak <jnovak@fel.cvut.cz>
+ *     Pavel Pisa <pisa@cmp.felk.cvut.cz>
+ *
+ * Department of Measurement         (http://meas.fel.cvut.cz/)
+ * Faculty of Electrical Engineering (http://www.fel.cvut.cz)
+ * Czech Technical University        (http://www.cvut.cz/)
+ ******************************************************************************/
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include "ctucanfd.h"
+
+#define DRV_NAME	"ctucanfd"
+
+static void ctucan_platform_set_drvdata(struct device *dev,
+					struct net_device *ndev)
+{
+	struct platform_device *pdev = container_of(dev, struct platform_device,
+						    dev);
+
+	platform_set_drvdata(pdev, ndev);
+}
+
+/**
+ * ctucan_platform_probe - Platform registration call
+ * @pdev:	Handle to the platform device structure
+ *
+ * This function does all the memory allocation and registration for the CAN
+ * device.
+ *
+ * Return: 0 on success and failure value on error
+ */
+static int ctucan_platform_probe(struct platform_device *pdev)
+{
+	struct resource *res; /* IO mem resources */
+	struct device	*dev = &pdev->dev;
+	void __iomem *addr;
+	int ret;
+	unsigned int ntxbufs;
+	int irq;
+
+	/* Get the virtual base address for the device */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	addr = devm_ioremap_resource(dev, res);
+	if (IS_ERR(addr)) {
+		dev_err(dev, "Cannot remap address.\n");
+		ret = PTR_ERR(addr);
+		goto err;
+	}
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(dev, "Cannot find interrupt.\n");
+		ret = irq;
+		goto err;
+	}
+
+	/* Number of tx bufs might be change in HW for future. If so,
+	 * it will be passed as property via device tree
+	 */
+	ntxbufs = 4;
+	ret = ctucan_probe_common(dev, addr, irq, ntxbufs, 0,
+				  1, ctucan_platform_set_drvdata);
+
+	if (ret < 0)
+		platform_set_drvdata(pdev, NULL);
+
+err:
+	return ret;
+}
+
+/**
+ * ctucan_platform_remove - Unregister the device after releasing the resources
+ * @pdev:	Handle to the platform device structure
+ *
+ * This function frees all the resources allocated to the device.
+ * Return: 0 always
+ */
+static int ctucan_platform_remove(struct platform_device *pdev)
+{
+	struct net_device *ndev = platform_get_drvdata(pdev);
+	struct ctucan_priv *priv = netdev_priv(ndev);
+
+	netdev_dbg(ndev, "ctucan_remove");
+
+	unregister_candev(ndev);
+	pm_runtime_disable(&pdev->dev);
+	netif_napi_del(&priv->napi);
+	free_candev(ndev);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(ctucan_platform_pm_ops, ctucan_suspend, ctucan_resume);
+
+/* Match table for OF platform binding */
+static const struct of_device_id ctucan_of_match[] = {
+	{ .compatible = "ctu,ctucanfd-2", },
+	{ .compatible = "ctu,ctucanfd", },
+	{ /* end of list */ },
+};
+MODULE_DEVICE_TABLE(of, ctucan_of_match);
+
+static struct platform_driver ctucanfd_driver = {
+	.probe	= ctucan_platform_probe,
+	.remove	= ctucan_platform_remove,
+	.driver	= {
+		.name = DRV_NAME,
+		.pm = &ctucan_platform_pm_ops,
+		.of_match_table	= ctucan_of_match,
+	},
+};
+
+module_platform_driver(ctucanfd_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Martin Jerabek");
+MODULE_DESCRIPTION("CTU CAN FD for platform");

drivers/net/can/dev/bittiming.c

@@ -116,7 +116,7 @@ int can_calc_bittiming(const struct net_device *dev, struct can_bittiming *bt,
 
 		can_update_sample_point(btc, sample_point_nominal, tseg / 2,
 					&tseg1, &tseg2, &sample_point_error);
-		if (sample_point_error > best_sample_point_error)
+		if (sample_point_error >= best_sample_point_error)
 			continue;
 
 		best_sample_point_error = sample_point_error;

drivers/net/can/dev/rx-offload.c

@@ -221,7 +221,7 @@ int can_rx_offload_irq_offload_fifo(struct can_rx_offload *offload)
 }
 EXPORT_SYMBOL_GPL(can_rx_offload_irq_offload_fifo);
 
-int can_rx_offload_queue_sorted(struct can_rx_offload *offload,
+int can_rx_offload_queue_timestamp(struct can_rx_offload *offload,
 				struct sk_buff *skb, u32 timestamp)
 {
 	struct can_rx_offload_cb *cb;
@@ -240,7 +240,7 @@ int can_rx_offload_queue_sorted(struct can_rx_offload *offload,
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(can_rx_offload_queue_sorted);
+EXPORT_SYMBOL_GPL(can_rx_offload_queue_timestamp);
 
 unsigned int can_rx_offload_get_echo_skb(struct can_rx_offload *offload,
 					 unsigned int idx, u32 timestamp,
@@ -256,7 +256,7 @@ unsigned int can_rx_offload_get_echo_skb(struct can_rx_offload *offload,
 	if (!skb)
 		return 0;
 
-	err = can_rx_offload_queue_sorted(offload, skb, timestamp);
+	err = can_rx_offload_queue_timestamp(offload, skb, timestamp);
 	if (err) {
 		stats->rx_errors++;
 		stats->tx_fifo_errors++;

drivers/net/can/flexcan/flexcan-core.c

@@ -723,11 +723,9 @@ static int flexcan_get_berr_counter(const struct net_device *dev,
 	const struct flexcan_priv *priv = netdev_priv(dev);
 	int err;
 
-	err = pm_runtime_get_sync(priv->dev);
-	if (err < 0) {
-		pm_runtime_put_noidle(priv->dev);
+	err = pm_runtime_resume_and_get(priv->dev);
+	if (err < 0)
 		return err;
-	}
 
 	err = __flexcan_get_berr_counter(dev, bec);
 
@@ -845,7 +843,7 @@ static void flexcan_irq_bus_err(struct net_device *dev, u32 reg_esr)
 	if (tx_errors)
 		dev->stats.tx_errors++;
 
-	err = can_rx_offload_queue_sorted(&priv->offload, skb, timestamp);
+	err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp);
 	if (err)
 		dev->stats.rx_fifo_errors++;
 }
@@ -892,7 +890,7 @@ static void flexcan_irq_state(struct net_device *dev, u32 reg_esr)
 	if (unlikely(new_state == CAN_STATE_BUS_OFF))
 		can_bus_off(dev);
 
-	err = can_rx_offload_queue_sorted(&priv->offload, skb, timestamp);
+	err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp);
 	if (err)
 		dev->stats.rx_fifo_errors++;
 }
@@ -1700,11 +1698,9 @@ static int flexcan_open(struct net_device *dev)
 		return -EINVAL;
 	}
 
-	err = pm_runtime_get_sync(priv->dev);
-	if (err < 0) {
-		pm_runtime_put_noidle(priv->dev);
+	err = pm_runtime_resume_and_get(priv->dev);
+	if (err < 0)
 		return err;
-	}
 
 	err = open_candev(dev);
 	if (err)

drivers/net/can/m_can/m_can.c

@@ -464,7 +464,7 @@ static void m_can_receive_skb(struct m_can_classdev *cdev,
 		struct net_device_stats *stats = &cdev->net->stats;
 		int err;
 
-		err = can_rx_offload_queue_sorted(&cdev->offload, skb,
+		err = can_rx_offload_queue_timestamp(&cdev->offload, skb,
 						  timestamp);
 		if (err)
 			stats->rx_fifo_errors++;

drivers/net/can/mscan/mpc5xxx_can.c

@@ -14,6 +14,8 @@
 #include <linux/platform_device.h>
 #include <linux/netdevice.h>
 #include <linux/can/dev.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
 #include <linux/of_platform.h>
 #include <sysdev/fsl_soc.h>
 #include <linux/clk.h>

drivers/net/can/sja1000/Kconfig

@@ -107,7 +107,7 @@ config CAN_TSCAN1
 	depends on ISA
 	help
 	  This driver is for Technologic Systems' TSCAN-1 PC104 boards.
-	  http://www.embeddedarm.com/products/board-detail.php?product=TS-CAN1
+	  https://www.embeddedts.com/products/TS-CAN1
 	  The driver supports multiple boards and automatically configures them:
 	  PLD IO base addresses are read from jumpers JP1 and JP2,
 	  IRQ numbers are read from jumpers JP4 and JP5,

drivers/net/can/sja1000/tscan1.c

@@ -5,10 +5,9 @@
  * Copyright 2010 Andre B. Oliveira
  */
 
-/*
- * References:
- * - Getting started with TS-CAN1, Technologic Systems, Jun 2009
- *	http://www.embeddedarm.com/documentation/ts-can1-manual.pdf
+/* References:
+ * - Getting started with TS-CAN1, Technologic Systems, Feb 2022
+ *	https://docs.embeddedts.com/TS-CAN1
  */
 
 #include <linux/init.h>

drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c

@@ -37,6 +37,12 @@ static const struct mcp251xfd_devtype_data mcp251xfd_devtype_data_mcp2518fd = {
 	.model = MCP251XFD_MODEL_MCP2518FD,
 };
 
+static const struct mcp251xfd_devtype_data mcp251xfd_devtype_data_mcp251863 = {
+	.quirks = MCP251XFD_QUIRK_CRC_REG | MCP251XFD_QUIRK_CRC_RX |
+		MCP251XFD_QUIRK_CRC_TX | MCP251XFD_QUIRK_ECC,
+	.model = MCP251XFD_MODEL_MCP251863,
+};
+
 /* Autodetect model, start with CRC enabled. */
 static const struct mcp251xfd_devtype_data mcp251xfd_devtype_data_mcp251xfd = {
 	.quirks = MCP251XFD_QUIRK_CRC_REG | MCP251XFD_QUIRK_CRC_RX |
@@ -75,6 +81,8 @@ static const char *__mcp251xfd_get_model_str(enum mcp251xfd_model model)
 		return "MCP2517FD";
 	case MCP251XFD_MODEL_MCP2518FD:
 		return "MCP2518FD";
+	case MCP251XFD_MODEL_MCP251863:
+		return "MCP251863";
 	case MCP251XFD_MODEL_MCP251XFD:
 		return "MCP251xFD";
 	}
@@ -916,7 +924,7 @@ static int mcp251xfd_handle_rxovif(struct mcp251xfd_priv *priv)
 	cf->can_id |= CAN_ERR_CRTL;
 	cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
 
-	err = can_rx_offload_queue_sorted(&priv->offload, skb, timestamp);
+	err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp);
 	if (err)
 		stats->rx_fifo_errors++;
 
@@ -1021,7 +1029,7 @@ static int mcp251xfd_handle_ivmif(struct mcp251xfd_priv *priv)
 		return 0;
 
 	mcp251xfd_skb_set_timestamp(priv, skb, timestamp);
-	err = can_rx_offload_queue_sorted(&priv->offload, skb, timestamp);
+	err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp);
 	if (err)
 		stats->rx_fifo_errors++;
 
@@ -1094,7 +1102,7 @@ static int mcp251xfd_handle_cerrif(struct mcp251xfd_priv *priv)
 		cf->data[7] = bec.rxerr;
 	}
 
-	err = can_rx_offload_queue_sorted(&priv->offload, skb, timestamp);
+	err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp);
 	if (err)
 		stats->rx_fifo_errors++;
 
@@ -1259,7 +1267,8 @@ mcp251xfd_handle_eccif_recover(struct mcp251xfd_priv *priv, u8 nr)
 	 * - for mcp2518fd: offset not 0 or 1
 	 */
 	if (chip_tx_tail != tx_tail ||
-	    !(offset == 0 || (offset == 1 && mcp251xfd_is_2518(priv)))) {
+	    !(offset == 0 || (offset == 1 && (mcp251xfd_is_2518FD(priv) ||
+					      mcp251xfd_is_251863(priv))))) {
 		netdev_err(priv->ndev,
 			   "ECC Error information inconsistent (addr=0x%04x, nr=%d, tx_tail=0x%08x(%d), chip_tx_tail=%d, offset=%d).\n",
 			   addr, nr, tx_ring->tail, tx_tail, chip_tx_tail,
@@ -1697,7 +1706,7 @@ static int mcp251xfd_register_chip_detect(struct mcp251xfd_priv *priv)
 	else
 		devtype_data = &mcp251xfd_devtype_data_mcp2517fd;
 
-	if (!mcp251xfd_is_251X(priv) &&
+	if (!mcp251xfd_is_251XFD(priv) &&
 	    priv->devtype_data.model != devtype_data->model) {
 		netdev_info(ndev,
 			    "Detected %s, but firmware specifies a %s. Fixing up.\n",
@@ -1929,6 +1938,9 @@ static const struct of_device_id mcp251xfd_of_match[] = {
 	}, {
 		.compatible = "microchip,mcp2518fd",
 		.data = &mcp251xfd_devtype_data_mcp2518fd,
+	}, {
+		.compatible = "microchip,mcp251863",
+		.data = &mcp251xfd_devtype_data_mcp251863,
 	}, {
 		.compatible = "microchip,mcp251xfd",
 		.data = &mcp251xfd_devtype_data_mcp251xfd,
@@ -1945,6 +1957,9 @@ static const struct spi_device_id mcp251xfd_id_table[] = {
 	}, {
 		.name = "mcp2518fd",
 		.driver_data = (kernel_ulong_t)&mcp251xfd_devtype_data_mcp2518fd,
+	}, {
+		.name = "mcp251863",
+		.driver_data = (kernel_ulong_t)&mcp251xfd_devtype_data_mcp251863,
 	}, {
 		.name = "mcp251xfd",
 		.driver_data = (kernel_ulong_t)&mcp251xfd_devtype_data_mcp251xfd,

drivers/net/can/spi/mcp251xfd/mcp251xfd-rx.c

@@ -173,7 +173,7 @@ mcp251xfd_handle_rxif_one(struct mcp251xfd_priv *priv,
 	}
 
 	mcp251xfd_hw_rx_obj_to_skb(priv, hw_rx_obj, skb);
-	err = can_rx_offload_queue_sorted(&priv->offload, skb, hw_rx_obj->ts);
+	err = can_rx_offload_queue_timestamp(&priv->offload, skb, hw_rx_obj->ts);
 	if (err)
 		stats->rx_fifo_errors++;
 

drivers/net/can/spi/mcp251xfd/mcp251xfd.h

@@ -586,7 +586,8 @@ struct mcp251xfd_regs_status {
 enum mcp251xfd_model {
 	MCP251XFD_MODEL_MCP2517FD = 0x2517,
 	MCP251XFD_MODEL_MCP2518FD = 0x2518,
-	MCP251XFD_MODEL_MCP251XFD = 0xffff,	/* autodetect model */
+	MCP251XFD_MODEL_MCP251863 = 0x251863,
+	MCP251XFD_MODEL_MCP251XFD = 0xffffffff,	/* autodetect model */
 };
 
 struct mcp251xfd_devtype_data {
@@ -659,12 +660,13 @@ struct mcp251xfd_priv {
 static inline bool \
 mcp251xfd_is_##_model(const struct mcp251xfd_priv *priv) \
 { \
-	return priv->devtype_data.model == MCP251XFD_MODEL_MCP##_model##FD; \
+	return priv->devtype_data.model == MCP251XFD_MODEL_MCP##_model; \
 }
 
-MCP251XFD_IS(2517);
-MCP251XFD_IS(2518);
-MCP251XFD_IS(251X);
+MCP251XFD_IS(2517FD);
+MCP251XFD_IS(2518FD);
+MCP251XFD_IS(251863);
+MCP251XFD_IS(251XFD);
 
 static inline bool mcp251xfd_is_fd_mode(const struct mcp251xfd_priv *priv)
 {

drivers/net/can/ti_hecc.c

@@ -633,7 +633,7 @@ static int ti_hecc_error(struct net_device *ndev, int int_status,
 			cf->data[3] = CAN_ERR_PROT_LOC_ACK;
 
 		timestamp = hecc_read(priv, HECC_CANLNT);
-		err = can_rx_offload_queue_sorted(&priv->offload, skb,
+		err = can_rx_offload_queue_timestamp(&priv->offload, skb,
 						  timestamp);
 		if (err)
 			ndev->stats.rx_fifo_errors++;
@@ -668,7 +668,7 @@ static void ti_hecc_change_state(struct net_device *ndev,
 	}
 
 	timestamp = hecc_read(priv, HECC_CANLNT);
-	err = can_rx_offload_queue_sorted(&priv->offload, skb, timestamp);
+	err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp);
 	if (err)
 		ndev->stats.rx_fifo_errors++;
 }

drivers/net/can/xilinx_can.c

@@ -239,7 +239,7 @@ static const struct can_bittiming_const xcan_bittiming_const_canfd = {
 };
 
 /* AXI CANFD Data Bittiming constants as per AXI CANFD 1.0 specs */
-static struct can_bittiming_const xcan_data_bittiming_const_canfd = {
+static const struct can_bittiming_const xcan_data_bittiming_const_canfd = {
 	.name = DRIVER_NAME,
 	.tseg1_min = 1,
 	.tseg1_max = 16,
@@ -265,7 +265,7 @@ static const struct can_bittiming_const xcan_bittiming_const_canfd2 = {
 };
 
 /* AXI CANFD 2.0 Data Bittiming constants as per AXI CANFD 2.0 spec */
-static struct can_bittiming_const xcan_data_bittiming_const_canfd2 = {
+static const struct can_bittiming_const xcan_data_bittiming_const_canfd2 = {
 	.name = DRIVER_NAME,
 	.tseg1_min = 1,
 	.tseg1_max = 32,

include/linux/can/rx-offload.h

@@ -42,7 +42,7 @@ int can_rx_offload_add_manual(struct net_device *dev,
 int can_rx_offload_irq_offload_timestamp(struct can_rx_offload *offload,
 					 u64 reg);
 int can_rx_offload_irq_offload_fifo(struct can_rx_offload *offload);
-int can_rx_offload_queue_sorted(struct can_rx_offload *offload,
+int can_rx_offload_queue_timestamp(struct can_rx_offload *offload,
 				   struct sk_buff *skb, u32 timestamp);
 unsigned int can_rx_offload_get_echo_skb(struct can_rx_offload *offload,
 					 unsigned int idx, u32 timestamp,