From 771c568bcf915e708ae819ef9d07d862f7e2da86 Mon Sep 17 00:00:00 2001 From: Brian Norris Date: Tue, 30 Jul 2013 17:52:55 -0700 Subject: [PATCH] mtd: nand: add accessors, macros for in-memory BBT There is an abundance of magic numbers and complicated shifting/masking logic in the in-memory BBT code which makes the code unnecessary complex and hard to read. This patch adds macros to represent the 00b, 01b, 10b, and 11b memory-BBT magic numbers, as well as two accessor functions for reading and marking the memory-BBT bitfield for a given block. Signed-off-by: Brian Norris Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse --- drivers/mtd/nand/nand_bbt.c | 70 +++++++++++++++++++++++++++++++-------------- 1 file changed, 48 insertions(+), 22 deletions(-) diff --git a/drivers/mtd/nand/nand_bbt.c b/drivers/mtd/nand/nand_bbt.c index 2672643..4c57a9b 100644 --- a/drivers/mtd/nand/nand_bbt.c +++ b/drivers/mtd/nand/nand_bbt.c @@ -71,6 +71,28 @@ #include #include +#define BBT_BLOCK_GOOD 0x00 +#define BBT_BLOCK_WORN 0x01 +#define BBT_BLOCK_RESERVED 0x02 +#define BBT_BLOCK_FACTORY_BAD 0x03 + +#define BBT_ENTRY_MASK 0x03 +#define BBT_ENTRY_SHIFT 2 + +static inline uint8_t bbt_get_entry(struct nand_chip *chip, int block) +{ + uint8_t entry = chip->bbt[block >> BBT_ENTRY_SHIFT]; + entry >>= (block & BBT_ENTRY_MASK) * 2; + return entry & BBT_ENTRY_MASK; +} + +static inline void bbt_mark_entry(struct nand_chip *chip, int block, + uint8_t mark) +{ + uint8_t msk = (mark & BBT_ENTRY_MASK) << ((block & BBT_ENTRY_MASK) * 2); + chip->bbt[block >> BBT_ENTRY_SHIFT] |= msk; +} + static int check_pattern_no_oob(uint8_t *buf, struct nand_bbt_descr *td) { if (memcmp(buf, td->pattern, td->len)) @@ -216,7 +238,9 @@ static int read_bbt(struct mtd_info *mtd, uint8_t *buf, int page, int num, if (reserved_block_code && (tmp == reserved_block_code)) { pr_info("nand_read_bbt: reserved block at 0x%012llx\n", (loff_t)((offs << 2) + (act >> 1)) << this->bbt_erase_shift); - this->bbt[offs + (act >> 3)] |= 0x2 << (act & 0x06); + bbt_mark_entry(this, (offs << 2) + + (act >> 1), + BBT_BLOCK_RESERVED); mtd->ecc_stats.bbtblocks++; continue; } @@ -228,9 +252,13 @@ static int read_bbt(struct mtd_info *mtd, uint8_t *buf, int page, int num, (loff_t)((offs << 2) + (act >> 1)) << this->bbt_erase_shift); /* Factory marked bad or worn out? */ if (tmp == 0) - this->bbt[offs + (act >> 3)] |= 0x3 << (act & 0x06); + bbt_mark_entry(this, (offs << 2) + + (act >> 1), + BBT_BLOCK_FACTORY_BAD); else - this->bbt[offs + (act >> 3)] |= 0x1 << (act & 0x06); + bbt_mark_entry(this, (offs << 2) + + (act >> 1), + BBT_BLOCK_WORN); mtd->ecc_stats.badblocks++; } } @@ -526,7 +554,7 @@ static int create_bbt(struct mtd_info *mtd, uint8_t *buf, return ret; if (ret) { - this->bbt[i >> 3] |= 0x03 << (i & 0x6); + bbt_mark_entry(this, i >> 1, BBT_BLOCK_FACTORY_BAD); pr_warn("Bad eraseblock %d at 0x%012llx\n", i >> 1, (unsigned long long)from); mtd->ecc_stats.badblocks++; @@ -713,10 +741,9 @@ static int write_bbt(struct mtd_info *mtd, uint8_t *buf, for (i = 0; i < td->maxblocks; i++) { int block = startblock + dir * i; /* Check, if the block is bad */ - switch ((this->bbt[block >> 2] >> - (2 * (block & 0x03))) & 0x03) { - case 0x01: - case 0x03: + switch (bbt_get_entry(this, block)) { + case BBT_BLOCK_WORN: + case BBT_BLOCK_FACTORY_BAD: continue; } page = block << @@ -816,7 +843,7 @@ static int write_bbt(struct mtd_info *mtd, uint8_t *buf, /* Walk through the memory table */ for (i = 0; i < numblocks;) { uint8_t dat; - dat = this->bbt[bbtoffs + (i >> 2)]; + dat = bbt_get_entry(this, (bbtoffs << 2) + i); for (j = 0; j < 4; j++, i++) { int sftcnt = (i << (3 - sft)) & sftmsk; /* Do not store the reserved bbt blocks! */ @@ -1009,7 +1036,7 @@ static void mark_bbt_region(struct mtd_info *mtd, struct nand_bbt_descr *td) { struct nand_chip *this = mtd->priv; int i, j, chips, block, nrblocks, update; - uint8_t oldval, newval; + uint8_t oldval; /* Do we have a bbt per chip? */ if (td->options & NAND_BBT_PERCHIP) { @@ -1027,10 +1054,10 @@ static void mark_bbt_region(struct mtd_info *mtd, struct nand_bbt_descr *td) continue; block = td->pages[i] >> (this->bbt_erase_shift - this->page_shift); block <<= 1; - oldval = this->bbt[(block >> 3)]; - newval = oldval | (0x2 << (block & 0x06)); - this->bbt[(block >> 3)] = newval; - if ((oldval != newval) && td->reserved_block_code) + oldval = bbt_get_entry(this, block >> 1); + bbt_mark_entry(this, block >> 1, BBT_BLOCK_RESERVED); + if ((oldval != BBT_BLOCK_RESERVED) && + td->reserved_block_code) nand_update_bbt(mtd, (loff_t)block << (this->bbt_erase_shift - 1)); continue; } @@ -1041,10 +1068,9 @@ static void mark_bbt_region(struct mtd_info *mtd, struct nand_bbt_descr *td) block = i * nrblocks; block <<= 1; for (j = 0; j < td->maxblocks; j++) { - oldval = this->bbt[(block >> 3)]; - newval = oldval | (0x2 << (block & 0x06)); - this->bbt[(block >> 3)] = newval; - if (oldval != newval) + oldval = bbt_get_entry(this, block >> 1); + bbt_mark_entry(this, block >> 1, BBT_BLOCK_RESERVED); + if (oldval != BBT_BLOCK_RESERVED) update = 1; block += 2; } @@ -1361,18 +1387,18 @@ int nand_isbad_bbt(struct mtd_info *mtd, loff_t offs, int allowbbt) /* Get block number * 2 */ block = (int)(offs >> (this->bbt_erase_shift - 1)); - res = (this->bbt[block >> 3] >> (block & 0x06)) & 0x03; + res = bbt_get_entry(this, block >> 1); pr_debug("nand_isbad_bbt(): bbt info for offs 0x%08x: " "(block %d) 0x%02x\n", (unsigned int)offs, block >> 1, res); switch ((int)res) { - case 0x00: + case BBT_BLOCK_GOOD: return 0; - case 0x01: + case BBT_BLOCK_WORN: return 1; - case 0x02: + case BBT_BLOCK_RESERVED: return allowbbt ? 0 : 1; } return 1; -- 2.7.4