On 2020-04-20 13:53, Tudor.Ambarus@xxxxxxxxxxxxx wrote:
On Wednesday, April 15, 2020 4:48:30 PM EEST Mantas Pucka wrote:EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe There are 2 different chips (w25q256fv and w25q256jv) that share the same JEDEC ID. Only w25q256jv fully supports 4-byte opcodes. Use SFDP header version to differentiate between them. Signed-off-by: Mantas Pucka <mantas@xxxxxxxxxxxx> --- drivers/mtd/spi-nor/sfdp.c | 4 ---- drivers/mtd/spi-nor/sfdp.h | 6 ++++++ drivers/mtd/spi-nor/winbond.c | 30 ++++++++++++++++++++++++++++-- 3 files changed, 34 insertions(+), 6 deletions(-) diff --git a/drivers/mtd/spi-nor/sfdp.c b/drivers/mtd/spi-nor/sfdp.c index f6038d3..27838f6 100644 --- a/drivers/mtd/spi-nor/sfdp.c +++ b/drivers/mtd/spi-nor/sfdp.c @@ -21,10 +21,6 @@ #define SFDP_4BAIT_ID 0xff84 /* 4-byte Address Instruction Table */ #define SFDP_SIGNATURE 0x50444653U -#define SFDP_JESD216_MAJOR 1 -#define SFDP_JESD216_MINOR 0 -#define SFDP_JESD216A_MINOR 5 -#define SFDP_JESD216B_MINOR 6 struct sfdp_header { u32 signature; /* Ox50444653U <=> "SFDP" */ diff --git a/drivers/mtd/spi-nor/sfdp.h b/drivers/mtd/spi-nor/sfdp.h index e0a8ded..b84abd0 100644 --- a/drivers/mtd/spi-nor/sfdp.h +++ b/drivers/mtd/spi-nor/sfdp.h @@ -7,6 +7,12 @@ #ifndef __LINUX_MTD_SFDP_H #define __LINUX_MTD_SFDP_H +/* SFDP revisions */ +#define SFDP_JESD216_MAJOR 1 +#define SFDP_JESD216_MINOR 0 +#define SFDP_JESD216A_MINOR 5 +#define SFDP_JESD216B_MINOR 6 + /* Basic Flash Parameter Table */ /* diff --git a/drivers/mtd/spi-nor/winbond.c b/drivers/mtd/spi-nor/winbond.c index 17deaba..50b2478 100644 --- a/drivers/mtd/spi-nor/winbond.c +++ b/drivers/mtd/spi-nor/winbond.c @@ -8,6 +8,32 @@ #include "core.h" +static int +w25q256_post_bfpt_fixups(struct spi_nor *nor, + const struct sfdp_parameter_header *bfpt_header, + const struct sfdp_bfpt *bfpt, + struct spi_nor_flash_parameter *params) +{ + /* + * W25Q256JV supports 4B opcodes but W25Q256FV does not. + * Unfortunately, Winbond has re-used the same JEDEC ID for both + * variants which prevents us from defining a new entry in the parts + * table. + * To differentiate between W25Q256JV and W25Q256FV check SFDP header + * version: only JV has JESD216A compliant structure (version 5) + */ + + if (bfpt_header->major == SFDP_JESD216_MAJOR && + bfpt_header->minor == SFDP_JESD216A_MINOR)Not sure if this is generic enough. Are you sure that the JV version will never have an update for the sfdp tables?
No, I'm not sure. I also don't know about other changes that may come with a version update: will it have 4B opcode table? will it be different version again (say KV) with it's own quirks? Fix only what needs fixing was the idea. But I guess chances of new chip with no 4B opcodes and new SFDP table are pretty slim, so I'm OK with having >= in v2.
+ nor->flags |= SNOR_F_4B_OPCODES; + + return 0; +} + +static struct spi_nor_fixups w25q256_fixups = { + .post_bfpt = w25q256_post_bfpt_fixups, +}; +If the post_bfpt hook is called, you already have a valid bfpt table. If the differentiator between the JV and FV versions is that only the JV defines the SFDP tables, then your w25q256_post_bfpt_fixups() can look as: static int w25q256_post_bfpt_fixups() { nor->flags |= SNOR_F_4B_OPCODES; return 0; }
FV chip that I have, do actually have SFDP tables (with minor_version==0). I've saw Chuanhong reporting that some FV chips don't have SFDP, but certainly this is not the case for all of them.
Best regards, Mantas ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/
