diff options
Diffstat (limited to 'target/linux/ipq806x/patches-4.1/161-mtd-nand-Create-a-BBT-flag-to-access-bad-block-markers-in-raw-mode.patch')
| -rw-r--r-- | target/linux/ipq806x/patches-4.1/161-mtd-nand-Create-a-BBT-flag-to-access-bad-block-markers-in-raw-mode.patch | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/target/linux/ipq806x/patches-4.1/161-mtd-nand-Create-a-BBT-flag-to-access-bad-block-markers-in-raw-mode.patch b/target/linux/ipq806x/patches-4.1/161-mtd-nand-Create-a-BBT-flag-to-access-bad-block-markers-in-raw-mode.patch new file mode 100644 index 0000000..088b8cb --- /dev/null +++ b/target/linux/ipq806x/patches-4.1/161-mtd-nand-Create-a-BBT-flag-to-access-bad-block-markers-in-raw-mode.patch @@ -0,0 +1,84 @@ +Content-Type: text/plain; charset="utf-8" +MIME-Version: 1.0 +Content-Transfer-Encoding: 7bit +Subject: [v3, + 1/5] mtd: nand: Create a BBT flag to access bad block markers in raw + mode +From: Archit Taneja <architt@codeaurora.org> +X-Patchwork-Id: 6927081 +Message-Id: <1438578498-32254-2-git-send-email-architt@codeaurora.org> +To: linux-mtd@lists.infradead.org, dehrenberg@google.com, + cernekee@gmail.com, computersforpeace@gmail.com +Cc: linux-arm-msm@vger.kernel.org, agross@codeaurora.org, + sboyd@codeaurora.org, linux-kernel@vger.kernel.org, + Archit Taneja <architt@codeaurora.org> +Date: Mon, 3 Aug 2015 10:38:14 +0530 + +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 | 7 +++++++ + 3 files changed, 17 insertions(+), 2 deletions(-) + +--- a/drivers/mtd/nand/nand_base.c ++++ b/drivers/mtd/nand/nand_base.c +@@ -395,7 +395,11 @@ 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 +@@ -423,7 +423,11 @@ 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 +116,13 @@ 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. |