[PATCH v4 00/20] mtd: spi-nor: Quad Enable and (un)lock methods

Tudor.Ambarus at microchip.com Tudor.Ambarus at microchip.com
Wed Nov 6 22:27:21 PST 2019

On 11/02/2019 01:23 PM, Tudor Ambarus - M18064 wrote:
> From: Tudor Ambarus <tudor.ambarus at microchip.com>
> Tested on s25fl116k and w25q128jv-q.
> Fixed the clearing of QE bit on (un)lock() operations. Reworked the
> Quad Enable methods and the disabling of the block write protection
> at power-up.
> v4:
> - Use dev_dbg insted of dev_err for low level info
> - replace "&nor->bouncebuf[0]" with "nor->bouncebuf" and "&sr_cr[0]" with
>   "sr_cr". Update across all patches.
> v3: split patches, update retlen handling in sst_write.
> v2:
> - Introduce spi_nor_write_16bit_cr_and_check() as per Vignesh's suggestion. 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.
> - Fix SNOR_F_NO_READ_CR case in
>   "mtd: spi-nor: Rework the disabling of block write protection". 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().
> - Fix if statement in spi_nor_write_sr_and_check():
>   if (nor->flags & SNOR_F_HAS_16BIT_SR)
> - Fix documentation warnings.
> - New patch: "mtd: spi-nor: Check all the bits written, not just the BP ones".
> - Drop Global Unlock patches, will send them in a different patch set.
> The patch set can be tested using mtd-utils:
> 1/ do a read-erase-write-read-back test immediately after boot, to check
> the spi_nor_unlock_all() method. The focus is on the erase/write
> methods, we want to see if the flash is unlocked at power-up.
>         mtd_debug read /dev/mtd-yours offset size read-file
>         hexdump read-file
>         mtd_debug erase /dev/mtd-yours offset size
>         dd if=/dev/urandom of=write-file bs=please-choose count=please-choose
>         mtd_debug write /dev/mtd-yours offset write-file-size write-file
>         mtd_debug read /dev/mtd-yours offset write-file-size read-file
>         sha1sum read-file write-file
> 2/ lock flash then try to erase/write it, to see if the lock works
>         flash_lock /dev/mtd-yours offset block-count
>         Do the read-erase-write-read-back test from 1/. The contents of
>         flash should not change in the erase and write steps.
> 3/ unlock flash and do the read-erase-write-read-back from 1/. The value of the
>    QEE should not change and you should be able to erase and write the flash.
>    Test 1/ should be successful.
> Tudor Ambarus (20):
>   mtd: spi-nor: Use dev_dbg insted of dev_err for low level info
>   mtd: spi-nor: Print debug info inside Reg Ops methods
>   mtd: spi-nor: Check for errors after each Register Operation
>   mtd: spi-nor: Rename label as it is no longer generic
>   mtd: spi-nor: Void return type for spi_nor_clear_sr/fsr()
>   mtd: spi-nor: Move the WE and wait calls inside Write SR methods
>   mtd: spi-nor: Merge spi_nor_write_sr() and spi_nor_write_sr_cr()
>   mtd: spi-nor: Describe all the Reg Ops
>   mtd: spi-nor: Drop spansion_quad_enable()
>   mtd: spi-nor: Fix errno on Quad Enable methods
>   mtd: spi-nor: Check all the bits written, not just the BP ones
>   mtd: spi-nor: Print debug message when the read back test fails
>   mtd: spi-nor: Fix clearing of QE bit on lock()/unlock()
>   mtd: spi-nor: Extend the QE Read Back test to the entire SR byte
>   mtd: spi-nor: Extend the QE Read Back test to both SR1 and SR2
>   mtd: spi-nor: Rename CR_QUAD_EN_SPAN to SR2_QUAD_EN_BIT1
>   mtd: spi-nor: Merge spansion Quad Enable methods
>   mtd: spi-nor: Rename macronix_quad_enable to
>     spi_nor_sr1_bit6_quad_enable
>   mtd: spi-nor: Prepend "spi_nor_" to "sr2_bit7_quad_enable"
>   mtd: spi-nor: Rework the disabling of block write protection
>  drivers/mtd/spi-nor/spi-nor.c | 952 +++++++++++++++++++++++++-----------------
>  include/linux/mtd/spi-nor.h   |  12 +-
>  2 files changed, 583 insertions(+), 381 deletions(-)

Updated 1/20 to use dev_err() when the SR/FSR report program or erase fails, or
attempts of modifying a protected sector. Patches 1-12 applied to spi-nor/next.

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