kernel: make bcm47xxpart work with TRX flashed at bad block(s)

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>

Backport of r48061

git-svn-id: svn://svn.openwrt.org/openwrt/branches/chaos_calmer@48140 3c298f89-4303-0410-b956-a3cf2f4a3e73

3 files changed, 102 insertions, 2 deletions

diff --git a/target/linux/bcm53xx/patches-3.18/901-mtd-bcm47xxpart-workaround-for-Asus-RT-AC87U-asus-pa.patch b/target/linux/bcm53xx/patches-3.18/901-mtd-bcm47xxpart-workaround-for-Asus-RT-AC87U-asus-pa.patch
index 774a186263..d9537d594b 100644
--- a/target/linux/bcm53xx/patches-3.18/901-mtd-bcm47xxpart-workaround-for-Asus-RT-AC87U-asus-pa.patch
+++ b/target/linux/bcm53xx/patches-3.18/901-mtd-bcm47xxpart-workaround-for-Asus-RT-AC87U-asus-pa.patch
@@ -22,7 +22,7 @@ Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
  
  #include <uapi/linux/magic.h>
  
-@@ -132,6 +133,17 @@ static int bcm47xxpart_parse(struct mtd_
+@@ -159,6 +160,17 @@ static int bcm47xxpart_parse(struct mtd_
  			break;
  		}
  
diff --git a/target/linux/generic/patches-3.18/431-mtd-bcm47xxpart-check-for-bad-blocks-when-calculatin.patch b/target/linux/generic/patches-3.18/431-mtd-bcm47xxpart-check-for-bad-blocks-when-calculatin.patch
new file mode 100644
index 0000000000..6adac77669
--- /dev/null
+++ b/target/linux/generic/patches-3.18/431-mtd-bcm47xxpart-check-for-bad-blocks-when-calculatin.patch
@@ -0,0 +1,100 @@
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <zajec5@gmail.com>
+Date: Sat, 2 Jan 2016 01:04:52 +0100
+Subject: [PATCH] mtd: bcm47xxpart: check for bad blocks when calculating
+ offsets
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
+---
+ drivers/mtd/bcm47xxpart.c | 50 +++++++++++++++++++++++++++++++++++++----------
+ 1 file changed, 40 insertions(+), 10 deletions(-)
+
+--- a/drivers/mtd/bcm47xxpart.c
++++ b/drivers/mtd/bcm47xxpart.c
+@@ -61,6 +61,34 @@ static void bcm47xxpart_add_part(struct mtd_partition *part, const char *name,
+ 	part->mask_flags = mask_flags;
+ }
+ 
++/*
++ * Calculate real end offset (address) for a given amount of data. It checks
++ * all blocks skipping bad ones.
++ */
++static size_t bcm47xxpart_real_offset(struct mtd_info *master, size_t offset,
++				      size_t bytes)
++{
++	size_t real_offset = offset;
++
++	if (mtd_block_isbad(master, real_offset))
++		pr_warn("Base offset shouldn't be at bad block");
++
++	while (bytes >= master->erasesize) {
++		bytes -= master->erasesize;
++		real_offset += master->erasesize;
++		while (mtd_block_isbad(master, real_offset)) {
++			real_offset += master->erasesize;
++
++			if (real_offset >= master->size)
++				return real_offset - master->erasesize;
++		}
++	}
++
++	real_offset += bytes;
++
++	return real_offset;
++}
++
+ static const char *bcm47xxpart_trx_data_part_name(struct mtd_info *master,
+ 						  size_t offset)
+ {
+@@ -182,6 +210,8 @@ static int bcm47xxpart_parse(struct mtd_info *master,
+ 
+ 		/* TRX */
+ 		if (buf[0x000 / 4] == TRX_MAGIC) {
++			uint32_t tmp;
++
+ 			if (BCM47XXPART_MAX_PARTS - curr_part < 4) {
+ 				pr_warn("Not enough partitions left to register trx, scanning stopped!\n");
+ 				break;
+@@ -196,18 +226,18 @@ static int bcm47xxpart_parse(struct mtd_info *master,
+ 			i = 0;
+ 			/* We have LZMA loader if offset[2] points to sth */
+ 			if (trx->offset[2]) {
++				tmp = bcm47xxpart_real_offset(master, offset,
++							      trx->offset[i]);
+ 				bcm47xxpart_add_part(&parts[curr_part++],
+-						     "loader",
+-						     offset + trx->offset[i],
+-						     0);
++						     "loader", tmp, 0);
+ 				i++;
+ 			}
+ 
+ 			if (trx->offset[i]) {
++				tmp = bcm47xxpart_real_offset(master, offset,
++							      trx->offset[i]);
+ 				bcm47xxpart_add_part(&parts[curr_part++],
+-						     "linux",
+-						     offset + trx->offset[i],
+-						     0);
++						     "linux", tmp, 0);
+ 				i++;
+ 			}
+ 
+@@ -219,11 +249,11 @@ static int bcm47xxpart_parse(struct mtd_info *master,
+ 			if (trx->offset[i]) {
+ 				const char *name;
+ 
+-				name = bcm47xxpart_trx_data_part_name(master, offset + trx->offset[i]);
++				tmp = bcm47xxpart_real_offset(master, offset,
++							      trx->offset[i]);
++				name = bcm47xxpart_trx_data_part_name(master, tmp);
+ 				bcm47xxpart_add_part(&parts[curr_part++],
+-						     name,
+-						     offset + trx->offset[i],
+-						     0);
++						     name, tmp, 0);
+ 				i++;
+ 			}
+ 
diff --git a/target/linux/generic/patches-3.18/432-mtd-bcm47xxpart-detect-T_Meter-partition.patch b/target/linux/generic/patches-3.18/432-mtd-bcm47xxpart-detect-T_Meter-partition.patch
index a3b7c1f71f..9e5ca91e55 100644
--- a/target/linux/generic/patches-3.18/432-mtd-bcm47xxpart-detect-T_Meter-partition.patch
+++ b/target/linux/generic/patches-3.18/432-mtd-bcm47xxpart-detect-T_Meter-partition.patch
@@ -24,7 +24,7 @@ Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
  #define ML_MAGIC1			0x39685a42
  #define ML_MAGIC2			0x26594131
  #define TRX_MAGIC			0x30524448
-@@ -179,6 +180,15 @@ static int bcm47xxpart_parse(struct mtd_
+@@ -207,6 +208,15 @@ static int bcm47xxpart_parse(struct mtd_
  					     MTD_WRITEABLE);
  			continue;
  		}