Messages in this thread | | | Date | Wed, 14 Nov 2018 14:51:29 +0100 | From | Boris Brezillon <> | Subject | Re: [PATCH] mtd: spi-nor: Return error when nor->addr_width not match the device size |
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On Wed, 14 Nov 2018 20:56:05 +0800 Liu Xiang <liu.xiang6@zte.com.cn> wrote:
> In 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.
According to your other patch this NOR supports 4B opcode, which means the SFDP table is wrong.
> 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 not match
^does not
> the device size in spi_nor_parse_sfdp(). > > Suggested-by: Boris Brezillon <boris.brezillon@bootlin.com> > Signed-off-by: Liu Xiang <liu.xiang6@zte.com.cn> > --- > drivers/mtd/spi-nor/spi-nor.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c > index 3eba13a..77eaf22 100644 > --- a/drivers/mtd/spi-nor/spi-nor.c > +++ b/drivers/mtd/spi-nor/spi-nor.c > @@ -2669,6 +2669,10 @@ 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*/
Please add a white space after '/*' and before '*/':
/* If the device exceeds 16MiB, ->addr_width must be 4. */
> + if ((params->size > 0x1000000) && (nor->addr_width == 3))
Parens are not needed around sub-conditions:
if (params->size > 0x1000000 && nor->addr_width == 3)
> + return -EINVAL; > +
I'm not sure this is correct. Looks like some NORs only support 3B opcodes but have a "4-byte addressing" mode (see set_4byte() [1]). Don't know what's reported by the BFPT section in this case though (BFPT_DWORD1_ADDRESS_BYTES_3_ONLY or BFPT_DWORD1_ADDRESS_BYTES_3_OR_4).
Anyway, I think this check should be moved here [2] to cover the non-SFDP case.
> /* Fast Read settings. */ > for (i = 0; i < ARRAY_SIZE(sfdp_bfpt_reads); i++) { > const struct sfdp_bfpt_read *rd = &sfdp_bfpt_reads[i];
[1]https://elixir.bootlin.com/linux/v4.20-rc2/source/drivers/mtd/spi-nor/spi-nor.c#L278 [2]https://elixir.bootlin.com/linux/v4.20-rc2/source/drivers/mtd/spi-nor/spi-nor.c#L3758
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