[U-Boot] [U-BOOT PATCH 0/3] add support for spi-nor device on HiFive Unleashed board

[Bin Meng]

On Wed, Aug 14, 2019 at 1:08 AM Sagar Shrikant Kadam
<sagar.kadam at sifive.com> wrote:
>
> This patch series adds support for 32MiB SPI-NOR flash (is25wp256 from
> ISSI). Many thanks to Bhargav Shah <bhargavshah1988 at gmail.com> for
> porting the spi-nor patches from linux to U-boot in order to support
> this device.
> Ref: linux patches which are under review
> https://lkml.org/lkml/2019/7/2/859
>
> Linux has an option of registering post-bfpt fixups in order to over-ride
> the incorrect configuration of flash devices due to wrong SFDP entries read
> from the flash device during nor scan phase. The 1st patch introduces this
> support to register post bfpt fixup hook similar to that done in linux.
>
> The second patch in the series enables support for the flash device in
> single I/O mode. A post bfpt fixup is registered because the flash device
> gets BFPT_DWORD1_ADDRESS_BYTES_3_ONLY from BFPT table for address width,
> whereas the flash can support 4 byte address width.
> The SPI_NOR_HAS_BP3 bit indicates that the flash protection block has BP0
> to BP3 bits.
>
> Lock/Unlock mechanism:
> The implementation is based on stm_lock/unlock scheme and is validated for
> different number of blocks passed to sf command. Unlock scheme unilateraly
> clears all the protection bits of all blocks in the status register.
>
> The series is based on the master branch of[1]
> [1] https://gitlab.denx.de/u-boot/custodians/u-boot-riscv
>
> and is available in dev/sagark/hifive-spi-nor_v2 branch of[2]
> [2] https://github.com/sagsifive/u-boot.
>
> Flash operations like erase/read/write lock/unlock are verified and
> data integrity is checked using sf commands as follows:
>
> => sf write 0x80600000 0x0 0x2000000
> device 0 whole chip
> SF: 33554432 bytes @ 0x0 Written: OK
> => sf read 0x82700000 0x0 0x2000000
> device 0 whole chip
> SF: 33554432 bytes @ 0x0 Read: OK
> => cmp.b 0x80600000 0x82700000 0x2000000
> Total of 33554432 byte(s) were the same
>
> => sf protect lock 0x1000000 0x1000000
> => mw 0x80600000 0x12345678 0x2000000
> => sf write 0x80600000 0x0 0x2000000
>    Reset the board to flush out data from memory
> => sf probe
> => sf read 0x80600000 0x0 0x2000000
>    In memory dump after sf read from address 0x80600000 we can see that
>    upper 16MiB flash section is protected.
>
>
> Sagar Shrikant Kadam (3):
>   spi: nor: add spi-nor-fixup handlers for nor devices
>   spi: nor: add support for is25wp256
>   spi: riscv: use single bit mode for spi transfers
>
>  board/sifive/fu540/Kconfig     |   5 +
>  drivers/mtd/spi/sf_internal.h  |  23 +++
>  drivers/mtd/spi/spi-nor-core.c | 373 +++++++++++++++++++++++++++++++++++------
>  drivers/mtd/spi/spi-nor-ids.c  |   5 +
>  drivers/spi/spi-sifive.c       |   7 +-
>  include/linux/mtd/spi-nor.h    |   8 +
>  6 files changed, 363 insertions(+), 58 deletions(-)
>
> --

Warning! This patch series will brick the HiFive Unleashed board.

What I did was only:
=> sf probe

everything looks good as long as you don't power off the board.

But when you power off the board and power on, there is no console
output anymore.

I then re-flashed the board using SD card rescue image, and confirmed
that this single "sf probe" command will brick the board (once again!)

Regards,
Bin