/branches/gl-inet/target/linux/ipq806x/patches-4.14/0047-mtd-nand-Create-a-BBT-flag-to-access-bad-block-marke.patch |
@@ -0,0 +1,72 @@ |
From c7c6a0f50f9ac3620c611ce06ba1f9fafea0444e Mon Sep 17 00:00:00 2001 |
From: Archit Taneja <architt@codeaurora.org> |
Date: Mon, 3 Aug 2015 10:38:14 +0530 |
Subject: [PATCH 47/69] mtd: nand: Create a BBT flag to access bad block |
markers in raw mode |
|
Some controllers can access the factory bad block marker from OOB only |
when they read it in raw mode. When ECC is enabled, these controllers |
discard reading/writing bad block markers, preventing access to them |
altogether. |
|
The bbt driver assumes MTD_OPS_PLACE_OOB when scanning for bad blocks. |
This results in the nand driver's ecc->read_oob() op to be called, which |
works with ECC enabled. |
|
Create a new BBT option flag that tells nand_bbt to force the mode to |
MTD_OPS_RAW. This would result in the correct op being called for the |
underlying nand controller driver. |
|
Reviewed-by: Andy Gross <agross@codeaurora.org> |
Signed-off-by: Archit Taneja <architt@codeaurora.org> |
--- |
drivers/mtd/nand/nand_base.c | 6 +++++- |
drivers/mtd/nand/nand_bbt.c | 6 +++++- |
include/linux/mtd/bbm.h | 6 ++++++ |
3 files changed, 16 insertions(+), 2 deletions(-) |
|
--- a/drivers/mtd/nand/nand_base.c |
+++ b/drivers/mtd/nand/nand_base.c |
@@ -481,7 +481,11 @@ static int nand_default_block_markbad(st |
} else { |
ops.len = ops.ooblen = 1; |
} |
- ops.mode = MTD_OPS_PLACE_OOB; |
+ |
+ if (unlikely(chip->bbt_options & NAND_BBT_ACCESS_BBM_RAW)) |
+ ops.mode = MTD_OPS_RAW; |
+ else |
+ ops.mode = MTD_OPS_PLACE_OOB; |
|
/* Write to first/last page(s) if necessary */ |
if (chip->bbt_options & NAND_BBT_SCANLASTPAGE) |
--- a/drivers/mtd/nand/nand_bbt.c |
+++ b/drivers/mtd/nand/nand_bbt.c |
@@ -420,7 +420,11 @@ static int scan_block_fast(struct mtd_in |
ops.oobbuf = buf; |
ops.ooboffs = 0; |
ops.datbuf = NULL; |
- ops.mode = MTD_OPS_PLACE_OOB; |
+ |
+ if (unlikely(bd->options & NAND_BBT_ACCESS_BBM_RAW)) |
+ ops.mode = MTD_OPS_RAW; |
+ else |
+ ops.mode = MTD_OPS_PLACE_OOB; |
|
for (j = 0; j < numpages; j++) { |
/* |
--- a/include/linux/mtd/bbm.h |
+++ b/include/linux/mtd/bbm.h |
@@ -116,6 +116,12 @@ struct nand_bbt_descr { |
#define NAND_BBT_NO_OOB_BBM 0x00080000 |
|
/* |
+ * Force MTD_OPS_RAW mode when trying to access bad block markes from OOB. To |
+ * be used by controllers which can access BBM only when ECC is disabled, i.e, |
+ * when in RAW access mode |
+ */ |
+#define NAND_BBT_ACCESS_BBM_RAW 0x00100000 |
+/* |
* Flag set by nand_create_default_bbt_descr(), marking that the nand_bbt_descr |
* was allocated dynamicaly and must be freed in nand_release(). Has no meaning |
* in nand_chip.bbt_options. |