Merge
    spansion_no_read_cr_quad_enable()
    spansion_read_cr_quad_enable()
into
    spi_nor_sr2_bit1_quad_enable().

Reduce code duplication by introducing spi_nor_write_16bit_cr_and_check().
The Configuration Register contains bits that can be updated in future:
FREEZE, CMP. Provide a generic method that allows updating all bits
of the Configuration Register.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>

JEDEC Basic Flash Parameter Table, 15th DWORD, bits 22:20,
refers to this bit as "bit 1 of the status register 2".
Rename the macro accordingly.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>

Test that all the bits from Status Register 1 and Status Register 2
were written correctly.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>

spi_nor_unlock() unlocks blocks of memory or the entire flash memory
array, if requested. clear_sr_bp() unlocks the entire flash memory
array at boot time. This calls for some unification, clear_sr_bp() is
just an optimization for the case when the unlock request covers the
entire flash size.

Get rid of clear_sr_bp() and introduce spi_nor_unlock_all(), which is
just a call to spi_nor_unlock() for the entire flash memory array.
This fixes a bug that was present in spi_nor_spansion_clear_sr_bp().
When the QE bit was zero, we used the Write Status (01h) command with
one data byte, which might cleared the Status Register 2. We now always
use the Write Status (01h) command with two data bytes when
SNOR_F_HAS_16BIT_SR is set, to avoid clearing the Status Register 2.

The SNOR_F_NO_READ_CR case is treated as well. When the flash doesn't
support the CR Read command, we make an assumption about the value of
the QE bit. In spi_nor_init(), call spi_nor_quad_enable() first, then
spi_nor_unlock_all(), so that at the spi_nor_unlock_all() time we can
be sure the QE bit has value one, because of the previous call to
spi_nor_quad_enable().

Get rid of the MFR handling and implement specific manufacturer
default_init() fixup hooks.

Note that this changes a bit the logic for the SNOR_MFR_ATMEL,
SNOR_MFR_INTEL and SNOR_MFR_SST cases. Before this patch, the Atmel,
Intel and SST chips did not set the locking ops, but unlocked the entire
flash at boot time, while now they are setting the locking ops to
stm_locking_ops. This should work, since the disable of the block
protection at the boot time used the same Status Register bits to unlock
the flash, as in the stm_locking_ops case.
Suggested-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>

Make sure that when doing a lock() or an unlock() operation we don't clear
the QE bit from Status Register 2.

JESD216 revB or later offers information about the *default* Status
Register commands to use (see BFPT DWORDS[15], bits 22:20). In this
standard, Status Register 1 refers to the first data byte transferred on a
Read Status (05h) or Write Status (01h) command. Status register 2 refers
to the byte read using instruction 35h. Status register 2 is the second
byte transferred in a Write Status (01h) command.

Industry naming and definitions of these Status Registers may differ.
The definitions are described in JESD216B, BFPT DWORDS[15], bits 22:20.
There are cases in which writing only one byte to the Status Register 1
has the side-effect of clearing Status Register 2 and implicitly the Quad
Enable bit. This side-effect is hit just by the
BFPT_DWORD15_QER_SR2_BIT1_BUGGY and BFPT_DWORD15_QER_SR2_BIT1 cases.
Suggested-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>

Demystify where the EIO error occurs.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>

Check that all the bits written in the write_sr_and_check() method
match the status_new received value. Failing to write the other bits
is dangerous too, extend the check.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>

When the Read-Modify-Write-Read-Back Quad Enable methods failed on
the Read-Back, they returned -EINVAL. Since this is an I/O error,
return -EIO.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>

Drop the default spansion_quad_enable() method and replace it with
spansion_read_cr_quad_enable().

The function was buggy, it didn't care about the previous values
of the Status and Configuration Registers. spansion_read_cr_quad_enable()
is a Read-Modify-Write-Check function that keeps track of what were
the previous values of the Status and Configuration Registers.

In terms of instruction types sent to the flash, the only difference
between the spansion_quad_enable() and spansion_read_cr_quad_enable()
is that the later calls spi_nor_read_sr(). We can safely assume that all
flashes support spi_nor_read_sr(), because all flashes call it in
spi_nor_sr_ready(). The transition from spansion_quad_enable() to
spansion_read_cr_quad_enable() will not affect anybody, drop the buggy
code.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>

Document all the Register Operations.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>

Merge
static int spi_nor_write_sr(struct spi_nor *nor, u8 val)
static int spi_nor_write_sr_cr(struct spi_nor *nor, const u8 *sr_cr)
into
static int spi_nor_write_sr(struct spi_nor *nor, const u8 *sr, size_t len)

The Status Register can be written with one or two bytes. Merge
the two functions to avoid code duplication.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

Avoid duplicating code by moving the calls to spi_nor_write_enable() and
spi_nor_wait_till_ready() inside the Write Status Register methods.

Move spi_nor_write_sr() to avoid forward declaration of
spi_nor_wait_till_ready().
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

spi_nor_clear_sr() and spi_nor_clear_fsr() are called just in case
of errors. The callers didn't check their return value, make them
of type void.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

Rename 'sst_write_err' label to 'out' as it is no longer generic for
all the errors in the sst_write() method, and may introduce confusion.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

Check for the return vales of each Register Operation.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>

Spare the callers of printing debug messages by themselves.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>

What most users care about is "my dev is not working properly".
All low level information should be discovered when activating
the debug traces.

Keep error messages just for the following cases:
- when the SR/FSR report program or erase fails, or attempts of
  modifying a protected sector,
- when the JEDEC ID is not recognized,
- when the resume() call fails,
- when the spi_nor_check() fails.
Suggested-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>

spi_nor_read_raw() assigns the result of 'ssize_t spi_nor_read_data()'
to the 'int ret' variable, while 'ssize_t' is a 64-bit type and *int*
is a 32-bit type on the 64-bit machines. This silent truncation isn't
really valid, so fix up the variable's type.

Fixes: f384b352 ("mtd: spi-nor: parse Serial Flash Discoverable Parameters (SFDP) tables")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>

spi_nor_read() assigns the result of 'ssize_t spi_nor_read_data()'
to the 'int ret' variable, while 'ssize_t' is a 64-bit type and *int*
is a 32-bit type on the 64-bit machines. This silent truncation isn't
really valid, so fix up the variable's type.

Fixes: 59451e12 ("mtd: spi-nor: change return value of read/write")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>

Intel Comet Lake-H PCH has the same SPI serial flash controller as Comet
Lake-LP. Add Comet Lake-H PCI ID to the driver list of supported devices.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>

Print identifying information about struct device.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

Constify the data to write to the Status Register.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

In case the write of the first byte failed, retlen was incorrectly
incremented to *retlen += actual; on the exit path. retlen should be
incremented when actual data was written to the flash.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

Drop the error messages from the callers, since the callees
already print an error message in case of failure.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

Let the callers pass the pointer to the DMA-able buffer where
the value of the Configuration Register will be written. This way we
avoid the casts between int and u8, which can be confusing.

Callers stop compare the return value of spi_nor_read_cr() with negative,
spi_nor_read_cr() returns 0 on success and -errno otherwise.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

Let the callers pass the pointer to the DMA-able buffer where
the value of the Flag Status Register will be written. This way we
avoid the casts between int and u8, which can be confusing.

Caller stops compare the return value of spi_nor_read_fsr() with negative,
spi_nor_read_fsr() returns 0 on success and -errno otherwise.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

Let the callers pass the pointer to the DMA-able buffer where
the value of the Status Register will be written. This way we
avoid the casts between int and u8, which can be confusing.

Callers stop compare the return value of spi_nor_read_sr() with negative,
spi_nor_read_sr() returns 0 on success and -errno otherwise.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

Do not overwrite the error numbers received the Register Operations
methods.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

ret is already of type int.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

spi_mem_exec_op()
nor->controller_ops->write_reg()
nor->controller_ops->read_reg()
spi_nor_wait_till_ready()
Return 0 on success, -errno otherwise.

Stop compare with negative and compare with zero in all the register
operations methods.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

Group all register methods up in the file, to avoid forward
declarations.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

Two new lines, one after another, drop one.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

All the core functions should begin with "spi_nor_".
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

n_tx was never used, drop it. Replace 'const u8 *txbuf' with 'u8 opcode',
to comply with the SPI NOR int (*read_reg)() method. The 'const'
qualifier has no meaning for parameters passed by value, drop it.
Going furher, the opcode was passed to cqspi_calc_rdreg() and never used,
drop it.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

Move all SPI NOR controller driver specific ops in a dedicated
structure. 'struct spi_nor' becomes lighter.

Use size_t for lengths in 'int (*write_reg)()' and 'int (*read_reg)()'.
Rename wite/read_buf to buf, the name of the functions are
suggestive enough. Constify buf in int (*write_reg). Comply with these
changes in the SPI NOR controller drivers.
Suggested-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

The pointer to 'struct spi_nor' is kzalloc'ed above in the code.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

Tested on HiWiFi C526A

Datasheet is available at:
http://www.xinyahong.com/upLoad/product/month_1411/201411201256018276.pdfSigned-off-by: DENG Qingfang <dqfext@gmail.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>

Now that SPI flash controllers without a software sequencer are
supported, it's trivial to add support for CNL and its PCI ID.

Values from https://www.intel.com/content/dam/www/public/us/en/documents/datasheets/300-series-chipset-pch-datasheet-vol-2.pdfSigned-off-by: Jethro Beekman <jethro@fortanix.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>

Some flash controllers don't have a software sequencer. Avoid
configuring the register addresses for it, and double check
everywhere that its not accidentally trying to be used.

Every use of `sregs` is now guarded by a check of `sregs` or
`swseq_reg`. The check might be done in the calling function.
Signed-off-by: Jethro Beekman <jethro@fortanix.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>