Linux commit 771c568bcf91:
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: Ladislav Michl <ladis@xxxxxxxxxxxxxx>
---
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 1357c5cc6..ce1d22e5c 100644
--- a/drivers/mtd/nand/nand_bbt.c
+++ b/drivers/mtd/nand/nand_bbt.c
@@ -69,6 +69,28 @@
#include <errno.h>
#include <malloc.h>
+#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))
@@ -214,7 +236,9 @@ 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;
}
@@ -222,9 +246,13 @@ 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++;
}
}
@@ -520,7 +548,7 @@ 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++;
@@ -704,10 +732,9 @@ 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 <<
@@ -807,7 +834,7 @@ 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! */
@@ -1000,7 +1027,7 @@ 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) {
@@ -1018,10 +1045,10 @@ 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;
}
@@ -1032,10 +1059,9 @@ 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;
}
@@ -1352,18 +1378,18 @@ 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;
--
2.19.1
_______________________________________________
barebox mailing list
barebox@xxxxxxxxxxxxxxxxxxx
http://lists.infradead.org/mailman/listinfo/barebox
