Hi, Vignesh Thanks for your suggestion. I will send a new patch.
At 2019-03-19 13:22:15, "Vignesh Raghavendra" <vigne...@ti.com> wrote: >Hi, > >On 13/03/19 7:15 PM, Liu Xiang wrote: >> In some is25lp256, the DWORD1 of JEDEC Basic Flash Parameter Header >> is 0xfff920e5. So the DWORD1[18:17] Address Bytes bits are 0b00, >> means that 3-Byte only addressing. But the device size is larger >> than 16MB, nor->addr_width must be 4 to access the whole address. >> An error should be returned when nor->addr_width does not match >> the device size in spi_nor_parse_bfpt(). Then it can go back to >> use spi_nor_ids[] for setting the right addr_width. >> >> Suggested-by: Boris Brezillon <boris.brezil...@bootlin.com> >> Signed-off-by: Liu Xiang <liu.xia...@zte.com.cn> >> --- >> drivers/mtd/spi-nor/spi-nor.c | 8 ++++++++ >> 1 file changed, 8 insertions(+) >> >> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c >> index 6e13bbd..63933c7 100644 >> --- a/drivers/mtd/spi-nor/spi-nor.c >> +++ b/drivers/mtd/spi-nor/spi-nor.c >> @@ -2811,6 +2811,14 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor, >> } >> params->size >>= 3; /* Convert to bytes. */ >> >> + /* >> + * If the device exceeds 16MiB, addr_width must be 4. >> + * addr_width == 3 means the Address Bytes we are >> + * reading from BFPT is wrong. >> + */ > >JESD216 standard does not mandate flash devices >16MiB to always support >4 byte addressing opcode. So, its okay for flash vendor to support >>16MiB flash with 3 byte addressing and Bank/extended address register. > >> + if (params->size > 0x1000000 && nor->addr_width == 3) >> + return -EINVAL; >> + > >Assuming only DWORD1[18:17] bits are wrong, then returning from here >would mean we miss parsing Sector Erase settings, Quad Enable >Requirements etc from BFPT which is kind of bad. >I suggest to move the fix to[1], addr_width indicated in flash_info >struct of the device can take precedence over SFDP. > >[1]https://elixir.bootlin.com/linux/latest/source/drivers/mtd/spi-nor/spi-nor.c#L4106 > > >> /* Fast Read settings. */ >> for (i = 0; i < ARRAY_SIZE(sfdp_bfpt_reads); i++) { >> const struct sfdp_bfpt_read *rd = &sfdp_bfpt_reads[i]; >> > >-- >Regards >Vignesh
