[U-Boot] [PATCH] Revert "spi: add config option to enable the WP pin function on st micron flashes"

[Jagan Teki]

Hi Heiko,

On 23 December 2014 at 12:04, Heiko Schocher <hs at denx.de> wrote:
> Hello Jagan,
>
> Am 22.12.2014 09:58, schrieb Jagan Teki:
>>
>> On 18 December 2014 at 19:21, Jagannadha Sutradharudu Teki
>> <jagannadh.teki at gmail.com> wrote:
>>>
>>> This reverts commit 562f8df18da62ae02c4ace1e530451fe82c3312d.
>>>
>>> Never see the issue with N25Q128 flash without need of W#/Vpp signal
>>> during probe.
>>>
>>> Signed-off-by: Jagannadha Sutradharudu Teki <jagannadh.teki at gmail.com>
>>> Cc: Heiko Schocher <hs at denx.de>
>>> ---
>>>   README                        | 11 -----------
>>>   drivers/mtd/spi/sf_internal.h |  4 ----
>>>   drivers/mtd/spi/sf_probe.c    | 30 ------------------------------
>>>   3 files changed, 45 deletions(-)
>
>
> I found this issue on the aristainetos board, there the "W#/Vpp" signal
> is connected to a gpio pin.

Did you test the same board on Linux? what about the status there?

>
> BTW: What is with the patchset:
>
> [U-Boot] [PATCH v3 0/3] spi, sf: add mtdparts feature to spi and sf commands
> http://lists.denx.de/pipermail/u-boot/2014-September/188098.html
>
> Patchwork [U-Boot,v3,1/3] mtd, spi: add MTD layer driver
> http://patchwork.ozlabs.org/patch/386102/
>
> Patchwork [U-Boot,v3,2/3] mtd, nand: move common functions from cmd_nand.c
> to common place
> http://patchwork.ozlabs.org/patch/386103/
>
> Patchwork [U-Boot,v3,3/3] spi, sf: use offset and size in sf cmd from
> mtdpartition
> http://patchwork.ozlabs.org/patch/386101/

Will come back next.

>
>
>
>>>
>>> diff --git a/README b/README
>>> index 4ca04d0..908646f 100644
>>> --- a/README
>>> +++ b/README
>>> @@ -3090,17 +3090,6 @@ CBFS (Coreboot Filesystem) support
>>>                  memories can be connected with a given cs line.
>>>                  currently Xilinx Zynq qspi support these type of
>>> connections.
>>>
>>> -               CONFIG_SYS_SPI_ST_ENABLE_WP_PIN
>>> -               enable the W#/Vpp signal to disable writing to the status
>>> -               register on ST MICRON flashes like the N25Q128.
>>> -               The status register write enable/disable bit, combined
>>> with
>>> -               the W#/VPP signal provides hardware data protection for
>>> the
>>> -               device as follows: When the enable/disable bit is set to
>>> 1,
>>> -               and the W#/VPP signal is driven LOW, the status register
>>> -               nonvolatile bits become read-only and the WRITE STATUS
>>> REGISTER
>>> -               operation will not execute. The only way to exit this
>>> -               hardware-protected mode is to drive W#/VPP HIGH.
>>> -
>>>   - SystemACE Support:
>>>                  CONFIG_SYSTEMACE
>>>
>>> diff --git a/drivers/mtd/spi/sf_internal.h
>>> b/drivers/mtd/spi/sf_internal.h
>>> index 785f7a9..bd834dc 100644
>>> --- a/drivers/mtd/spi/sf_internal.h
>>> +++ b/drivers/mtd/spi/sf_internal.h
>>> @@ -97,10 +97,6 @@ enum {
>>>   #define STATUS_QEB_MXIC                (1 << 6)
>>>   #define STATUS_PEC                     (1 << 7)
>>>
>>> -#ifdef CONFIG_SYS_SPI_ST_ENABLE_WP_PIN
>>> -#define STATUS_SRWD                    (1 << 7) /* SR write protect */
>>> -#endif
>>> -
>>>   /* Flash timeout values */
>>>   #define SPI_FLASH_PROG_TIMEOUT         (2 * CONFIG_SYS_HZ)
>>>   #define SPI_FLASH_PAGE_ERASE_TIMEOUT           (5 * CONFIG_SYS_HZ)
>>> diff --git a/drivers/mtd/spi/sf_probe.c b/drivers/mtd/spi/sf_probe.c
>>> index ce9987f..3b0e652 100644
>>> --- a/drivers/mtd/spi/sf_probe.c
>>> +++ b/drivers/mtd/spi/sf_probe.c
>>> @@ -287,34 +287,6 @@ int spi_flash_decode_fdt(const void *blob, struct
>>> spi_flash *flash)
>>>   }
>>>   #endif /* CONFIG_OF_CONTROL */
>>>
>>> -#ifdef CONFIG_SYS_SPI_ST_ENABLE_WP_PIN
>>> -/* enable the W#/Vpp signal to disable writing to the status register */
>>> -static int spi_enable_wp_pin(struct spi_flash *flash)
>>> -{
>>> -       u8 status;
>>> -       int ret;
>>> -
>>> -       ret = spi_flash_cmd_read_status(flash, &status);
>>> -       if (ret < 0)
>>> -               return ret;
>>> -
>>> -       ret = spi_flash_cmd_write_status(flash, STATUS_SRWD);
>>> -       if (ret < 0)
>>> -               return ret;
>>> -
>>> -       ret = spi_flash_cmd_write_disable(flash);
>>> -       if (ret < 0)
>>> -               return ret;
>>> -
>>> -       return 0;
>>> -}
>>> -#else
>>> -static int spi_enable_wp_pin(struct spi_flash *flash)
>>> -{
>>> -       return 0;
>>> -}
>>> -#endif
>>> -
>>>   /**
>>>    * spi_flash_probe_slave() - Probe for a SPI flash device on a bus
>>>    *
>>> @@ -393,8 +365,6 @@ int spi_flash_probe_slave(struct spi_slave *spi,
>>> struct spi_flash *flash)
>>>                  puts(" Full access #define CONFIG_SPI_FLASH_BAR\n");
>>>          }
>>>   #endif
>>> -       if (spi_enable_wp_pin(flash))
>>> -               puts("Enable WP pin failed\n");
>>>
>>>          /* Release spi bus */
>>>          spi_release_bus(spi);
>>> --
>>> 1.9.1
>>>
>>
>> Ping!

thanks!
-- 
Jagan.