Allwinner V3s has a DMA engine similar to the ones from A31, but with
fewer channels and DRQs.

Add support for it.
Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Originally we enable a special gate bit when the compatible indicates
A23/33.

But according to BSP sources and user manuals, more SoCs will need this
gate bit.

So make it a common quirk configured in the config struct.
Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Renesas R-Car V3M (R8A77970) SoC also has the R-Car gen2/3 compatible DMA
controllers, so document the SoC specific binding.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

'err' is a signed int and error codes are typically negative numbers, so
use '%d' instead of '%u' to format the error code in the error message.

Fixes: ba16db36 ("dmaengine: vdma: Add clock support")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

This patch moves from a struct declaration for the DMA controller
registers to macros with offests to the base address. This is mainly
done to remove the sparse warnings, since the function parameter of
ioread32/iowrite32 is "void __iomem *" instead of a pointer to struct
members. With this patch applied, no sparse warning is seen anymore.

Please note that the struct for the descriptors is still kept in place,
as the code largely accesses the struct members as internal variables
before the complete struct is copied into the descriptor FIFO of the
DMA controller.

Additionally this patch also removes two warnings "variable xxx set but
not used" seen when compiling with "W=1". The registers need to be read
to flush the response FIFO, but nothing needs to be done with them. So
the code is correct here and the warning is a false one.
Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

DMA crossbar uses 'xbar->dma_inuse' variable to manage allocated routes.
Each bit represents respective DMA channel. If the channel is free, bit
is set to '0', if channel is allocated, bit should be set to '1'.

In reserve function, the bits for requested DMA channels are cleared, so
they are not really reserved, but freed and become ready for allocation.
Signed-off-by: Alexander Smirnov <asmirnov@ilbers.de>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

amba_id are not supposed to change at runtime. All functions
working with const amba_id. So mark the non-const structs as const.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

amba_id are not supposed to change at runtime. All functions
working with const amba_id. So mark the non-const structs as const.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The SBA_REQUEST_STATE_COMPLETED state was added to keep track
of sba_request which got completed but cannot be freed because
underlying Async Tx descriptor was not ACKed by DMA client.

Instead of above, we can free the sba_request with non-ACKed
Async Tx descriptor and sba_alloc_request() will ensure that
it always allocates sba_request with ACKed Async Tx descriptor.
This alternate approach makes SBA_REQUEST_STATE_COMPLETED state
redundant hence this patch removes it.
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

We should explicitly ACK mailbox message because after
sending message we can know the send status via error
attribute of brcm_message.

This will also help SBA-RAID to use "txdone_ack" method
whenever mailbox controller supports it.
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

This patch adds debugfs support to report stats via debugfs
which in-turn will help debug hang or error situations.
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The SBA_REQUEST_STATE_RECEIVED state is now redundant because
received sba_request are immediately freed or moved to completed
list in sba_process_received_request().

This patch removes redundant SBA_REQUEST_STATE_RECEIVED state.
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Currently, sba_process_deferred_requests() handles both pending
and completed sba_request which is unnecessary overhead for
sba_issue_pending() because completed sba_request handling is
not required in sba_issue_pending().

This patch breaks sba_process_deferred_requests() into two parts
sba_process_received_request() and _sba_process_pending_requests().

The sba_issue_pending() will only process pending sba_request
by calling _sba_process_pending_requests(). This will improve
sba_issue_pending().

The sba_receive_message() will only process received sba_request
by calling sba_process_received_request() for each received
sba_request. The sba_process_received_request() will also call
_sba_process_pending_requests() after handling received sba_request
because we might have pending sba_request not submitted by previous
call to sba_issue_pending().
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

We should pre-ack async tx descriptor at time of
allocating sba_request (just like other RAID drivers).
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

When setting up RAID array on several NVMe disks we observed that
sba_alloc_request() start failing (due to no free requests left)
and RAID array setup becomes very slow.

To improve performance, we do mbox channel peek when we have
no free requests. This improves performance of RAID array setup
because mbox requests that were completed but not processed by
mbox completion worker will be processed immediately by mbox
channel peek.
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

We should allocate DMA channel resources before registering the
DMA device in sba_probe() because we can get DMA request soon
after registering the DMA device. If DMA channel resources are
not allocated before first DMA request then SBA-RAID driver will
crash.
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The pending sba_request list can become very long in real-life usage
(e.g. setting up RAID array) which can cause sba_issue_pending() to
run for long duration.

This patch adds common sba_process_deferred_requests() to process
few completed and pending requests so that it finishes in short
duration. We use this common sba_process_deferred_requests() in
both sba_issue_pending() and sba_receive_message().
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Currently, we have only 1024 free sba_request created
by sba_prealloc_channel_resources(). This is too low
and the prep_xxx() callbacks start failing more often
at time of RAID array setup over NVMe disks.

This patch sets number of free sba_request created by
sba_prealloc_channel_resources() to be:
<number_of_mailbox_channels> x 8192

Due to above, we will have sufficient number of free
sba_request and prep_xxx() callbacks failing is very
unlikely.
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Currently, we cannot have any arbitrary number of free sba_request
because sba_prealloc_channel_resources() allocates an array of
sba_request using devm_kcalloc() and kcalloc() cannot provide
memory beyond certain size.

This patch removes "reqs" (sba_request array) from sba_device
and makes "cmds" as variable array (instead of pointer) in
sba_request. This helps sba_prealloc_channel_resources() to
allocate sba_request and associated SBA command in one allocation
which in-turn allows arbitrary number of free sba_request.
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The reqs_free_count member of sba_device is not used anywhere
hence no point in tracking number of free sba_request.
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Both resp and resp_dma are redundant in sba_request because
resp is unused and resp_dma carries same information present
in tx.phys of sba_request. This patch removes both resp and
resp_dma from sba_request.
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The next_count in sba_request is redundant because same information
is captured by next_pending_count. This patch removes next_count
from sba_request.
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

This patch merges sba_request state and fence into common
sba_request flags. The sba_request flags not only saves
memory but it can also be extended in-future without adding
new members.

We also make each sba_request state as separate bit in
sba_request flags to help debugging situations where a
sba_request is accidently in two states.
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

We don't require to hold "sba->reqs_lock" for long-time
in sba_alloc_request() because lock protection is not
required when initializing members of "struct sba_request".
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

This patch does following improvments to comments:
1. Make section comments consistent across the driver by
avoiding " SBA " in some of the comments
2. Add/update few more section comments
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Anton Volkov noticed that engine->dev is NULL before
of_dma_controller_register() in probe.
Thus there might be a NULL pointer dereference in
rcar_dmac_chan_start_xfer while accessing chan->chan.device->dev which
is equal to (&dmac->engine)->dev.
On same reason, same and similar things will happen if we didn't
initialize all necessary data before calling register irq function.
To be more safety code, this patch initialize all necessary data
before calling register irq function.
Reported-by: Anton Volkov <avolkov@ispras.ru>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Commit c678fa66: ("dmaengine: remove DMA_SG as it is dead code in
kernel") removes DMA_SG from dmaengine subsystem but missed the newly added
driver, so remove it from here as well
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

clk_prepare_enable() can fail here and we must check its return value.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Replace '%d' by '%zu' to fix the compilation warning:-
   "format ‘%d’ expects argument of type ‘int’,but argument has type ‘size_t’ [-Wformat=]"
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Make these const as they are only used during a copy operation.
Done using Coccinelle.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

This patch adds R-Car M3-W device tree bindings for usb-dmac driver.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

This driver builds with warnings which can be fixed by making these
functions static.

  CC [M]  drivers/dma/bcm-sba-raid.o
drivers/dma/bcm-sba-raid.c:786:1: warning: no previous prototype for ‘sba_prep_dma_xor_req’ [-Wmissing-prototypes]
 sba_prep_dma_xor_req(struct sba_device *sba,
 ^
drivers/dma/bcm-sba-raid.c:995:1: warning: no previous prototype for ‘sba_prep_dma_pq_req’ [-Wmissing-prototypes]
 sba_prep_dma_pq_req(struct sba_device *sba, dma_addr_t off,
 ^
drivers/dma/bcm-sba-raid.c:1247:1: warning: no previous prototype for ‘sba_prep_dma_pq_single_req’ [-Wmissing-prototypes]
 sba_prep_dma_pq_single_req(struct sba_device *sba, dma_addr_t off,
 ^
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

This driver adds support for the Altera / Intel modular Scatter-Gather
Direct Memory Access (mSGDMA) intellectual property (IP) to the Linux
DMAengine subsystem. Currently it supports the following op modes:

- DMA_MEMCPY
- DMA_SG
- DMA_SLAVE

This implementation has been tested on an Altera Cyclone FPGA connected
via PCIe, both on an ARM and an x86 platform.
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Pull documentation format standardization from Jonathan Corbet:
 "This series converts a number of top-level documents to the RST format
  without incorporating them into the Sphinx tree. The hope is to bring
  some uniformity to kernel documentation and, perhaps more importantly,
  have our existing docs serve as an example of the desired formatting
  for those that will be added later.

  Mauro has gone through and fixed up a lot of top-level documentation
  files to make them conform to the RST format, but without moving or
  renaming them in any way. This will help when we incorporate the ones
  we want to keep into the Sphinx doctree, but the real purpose is to
  bring a bit of uniformity to our documentation and let the top-level
  docs serve as examples for those writing new ones"

* tag 'standardize-docs' of git://git.lwn.net/linux: (84 commits)
  docs: kprobes.txt: Fix whitespacing
  tee.txt: standardize document format
  cgroup-v2.txt: standardize document format
  dell_rbu.txt: standardize document format
  zorro.txt: standardize document format
  xz.txt: standardize document format
  xillybus.txt: standardize document format
  vfio.txt: standardize document format
  vfio-mediated-device.txt: standardize document format
  unaligned-memory-access.txt: standardize document format
  this_cpu_ops.txt: standardize document format
  svga.txt: standardize document format
  static-keys.txt: standardize document format
  smsc_ece1099.txt: standardize document format
  SM501.txt: standardize document format
  siphash.txt: standardize document format
  sgi-ioc4.txt: standardize document format
  SAK.txt: standardize document format
  rpmsg.txt: standardize document format
  robust-futexes.txt: standardize document format
  ...

Pull random updates from Ted Ts'o:
 "Add wait_for_random_bytes() and get_random_*_wait() functions so that
  callers can more safely get random bytes if they can block until the
  CRNG is initialized.

  Also print a warning if get_random_*() is called before the CRNG is
  initialized. By default, only one single-line warning will be printed
  per boot. If CONFIG_WARN_ALL_UNSEEDED_RANDOM is defined, then a
  warning will be printed for each function which tries to get random
  bytes before the CRNG is initialized. This can get spammy for certain
  architecture types, so it is not enabled by default"

* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
  random: reorder READ_ONCE() in get_random_uXX
  random: suppress spammy warnings about unseeded randomness
  random: warn when kernel uses unseeded randomness
  net/route: use get_random_int for random counter
  net/neighbor: use get_random_u32 for 32-bit hash random
  rhashtable: use get_random_u32 for hash_rnd
  ceph: ensure RNG is seeded before using
  iscsi: ensure RNG is seeded before use
  cifs: use get_random_u32 for 32-bit lock random
  random: add get_random_{bytes,u32,u64,int,long,once}_wait family
  random: add wait_for_random_bytes() API

Pull ->s_options removal from Al Viro:
 "Preparations for fsmount/fsopen stuff (coming next cycle). Everything
  gets moved to explicit ->show_options(), killing ->s_options off +
  some cosmetic bits around fs/namespace.c and friends. Basically, the
  stuff needed to work with fsmount series with minimum of conflicts
  with other work.

  It's not strictly required for this merge window, but it would reduce
  the PITA during the coming cycle, so it would be nice to have those
  bits and pieces out of the way"

* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  isofs: Fix isofs_show_options()
  VFS: Kill off s_options and helpers
  orangefs: Implement show_options
  9p: Implement show_options
  isofs: Implement show_options
  afs: Implement show_options
  affs: Implement show_options
  befs: Implement show_options
  spufs: Implement show_options
  bpf: Implement show_options
  ramfs: Implement show_options
  pstore: Implement show_options
  omfs: Implement show_options
  hugetlbfs: Implement show_options
  VFS: Don't use save/replace_mount_options if not using generic_show_options
  VFS: Provide empty name qstr
  VFS: Make get_filesystem() return the affected filesystem
  VFS: Clean up whitespace in fs/namespace.c and fs/super.c
  Provide a function to create a NUL-terminated string from unterminated data

Pull more __copy_.._user elimination from Al Viro.

* 'work.__copy_to_user' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  drm_dp_aux_dev: switch to read_iter/write_iter