lkml.org 
[lkml]   [2020]   [Sep]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] mtd: spi-nor: Fix 3-or-4 address byte mode logic
Date
Flash chips that announce BFPT_DWORD1_ADDRESS_BYTES_3_OR_4 capability
get an addr_width of 3. This breaks when the flash chip is actually
larger than 16MB, since that requires a 4-byte address. The MX25L25635F
does exactly this, breaking anything over 16MB.

spi-nor only enables 4-byte opcodes or 4-byte address mode if addr_width
is 4, so no 4-byte mode is ever enabled. The > 16MB check in
spi_nor_set_addr_width() only works if addr_width wasn't already set
by the SFDP, which it was.

It could be fixed in a post_bfpt fixup for the MX25L25635F, but setting
addr_width to 4 when BFPT_DWORD1_ADDRESS_BYTES_3_OR_4 is found fixes the
problem for all such cases.

Signed-off-by: Bert Vermeulen <bert@biot.com>
---
drivers/mtd/spi-nor/sfdp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/spi-nor/sfdp.c b/drivers/mtd/spi-nor/sfdp.c
index e2a43d39eb5f..6fedc425bcf7 100644
--- a/drivers/mtd/spi-nor/sfdp.c
+++ b/drivers/mtd/spi-nor/sfdp.c
@@ -456,10 +456,10 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
/* Number of address bytes. */
switch (bfpt.dwords[BFPT_DWORD(1)] & BFPT_DWORD1_ADDRESS_BYTES_MASK) {
case BFPT_DWORD1_ADDRESS_BYTES_3_ONLY:
- case BFPT_DWORD1_ADDRESS_BYTES_3_OR_4:
nor->addr_width = 3;
break;

+ case BFPT_DWORD1_ADDRESS_BYTES_3_OR_4:
case BFPT_DWORD1_ADDRESS_BYTES_4_ONLY:
nor->addr_width = 4;
break;
--
2.17.1
\
 
 \ /
  Last update: 2020-10-01 02:22    [W:0.072 / U:2.876 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site