mtd: cfi_cmdset_0002: Add support for writing OTP memory

This patch adds support for writing the one time programmable (OTP)
memory of Micron M29EW devices.

Signed-off-by: Christian Riesch <christian.riesch@omicron.at>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
This commit is contained in:
Christian Riesch 2014-03-06 13:18:29 +01:00 committed by Brian Norris
parent feb8677935
commit af74475057

View File

@ -67,6 +67,8 @@ static int cfi_amdstd_read_fact_prot_reg(struct mtd_info *, loff_t, size_t,
size_t *, u_char *);
static int cfi_amdstd_read_user_prot_reg(struct mtd_info *, loff_t, size_t,
size_t *, u_char *);
static int cfi_amdstd_write_user_prot_reg(struct mtd_info *, loff_t, size_t,
size_t *, u_char *);
static int cfi_amdstd_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const u_char *buf);
@ -530,6 +532,7 @@ struct mtd_info *cfi_cmdset_0002(struct map_info *map, int primary)
mtd->_read_fact_prot_reg = cfi_amdstd_read_fact_prot_reg;
mtd->_get_fact_prot_info = cfi_amdstd_get_fact_prot_info;
mtd->_get_user_prot_info = cfi_amdstd_get_user_prot_info;
mtd->_write_user_prot_reg = cfi_amdstd_write_user_prot_reg;
mtd->flags = MTD_CAP_NORFLASH;
mtd->name = map->name;
mtd->writesize = 1;
@ -1257,6 +1260,40 @@ static int cfi_amdstd_secsi_read (struct mtd_info *mtd, loff_t from, size_t len,
return ret;
}
static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
unsigned long adr, map_word datum,
int mode);
static int do_otp_write(struct map_info *map, struct flchip *chip, loff_t adr,
size_t len, u_char *buf)
{
int ret;
while (len) {
unsigned long bus_ofs = adr & ~(map_bankwidth(map)-1);
int gap = adr - bus_ofs;
int n = min_t(int, len, map_bankwidth(map) - gap);
map_word datum;
if (n != map_bankwidth(map)) {
/* partial write of a word, load old contents */
otp_enter(map, chip, bus_ofs, map_bankwidth(map));
datum = map_read(map, bus_ofs);
otp_exit(map, chip, bus_ofs, map_bankwidth(map));
}
datum = map_word_load_partial(map, datum, buf, gap, n);
ret = do_write_oneword(map, chip, bus_ofs, datum, FL_OTP_WRITE);
if (ret)
return ret;
adr += n;
buf += n;
len -= n;
}
return 0;
}
static int cfi_amdstd_otp_walk(struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char *buf,
otp_op_t action, int user_regs)
@ -1400,7 +1437,17 @@ static int cfi_amdstd_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
buf, do_read_secsi_onechip, 1);
}
static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip, unsigned long adr, map_word datum)
static int cfi_amdstd_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
size_t len, size_t *retlen,
u_char *buf)
{
return cfi_amdstd_otp_walk(mtd, from, len, retlen, buf,
do_otp_write, 1);
}
static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
unsigned long adr, map_word datum,
int mode)
{
struct cfi_private *cfi = map->fldrv_priv;
unsigned long timeo = jiffies + HZ;
@ -1421,7 +1468,7 @@ static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
adr += chip->start;
mutex_lock(&chip->mutex);
ret = get_chip(map, chip, adr, FL_WRITING);
ret = get_chip(map, chip, adr, mode);
if (ret) {
mutex_unlock(&chip->mutex);
return ret;
@ -1430,6 +1477,9 @@ static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
pr_debug("MTD %s(): WRITE 0x%.8lx(0x%.8lx)\n",
__func__, adr, datum.x[0] );
if (mode == FL_OTP_WRITE)
otp_enter(map, chip, adr, map_bankwidth(map));
/*
* Check for a NOP for the case when the datum to write is already
* present - it saves time and works around buggy chips that corrupt
@ -1446,12 +1496,13 @@ static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
XIP_INVAL_CACHED_RANGE(map, adr, map_bankwidth(map));
ENABLE_VPP(map);
xip_disable(map, chip, adr);
retry:
cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
cfi_send_gen_cmd(0xA0, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
map_write(map, datum, adr);
chip->state = FL_WRITING;
chip->state = mode;
INVALIDATE_CACHE_UDELAY(map, chip,
adr, map_bankwidth(map),
@ -1460,7 +1511,7 @@ static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
/* See comment above for timeout value. */
timeo = jiffies + uWriteTimeout;
for (;;) {
if (chip->state != FL_WRITING) {
if (chip->state != mode) {
/* Someone's suspended the write. Sleep */
DECLARE_WAITQUEUE(wait, current);
@ -1500,6 +1551,8 @@ static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
}
xip_enable(map, chip, adr);
op_done:
if (mode == FL_OTP_WRITE)
otp_exit(map, chip, adr, map_bankwidth(map));
chip->state = FL_READY;
DISABLE_VPP(map);
put_chip(map, chip, adr);
@ -1555,7 +1608,7 @@ static int cfi_amdstd_write_words(struct mtd_info *mtd, loff_t to, size_t len,
tmp_buf = map_word_load_partial(map, tmp_buf, buf, i, n);
ret = do_write_oneword(map, &cfi->chips[chipnum],
bus_ofs, tmp_buf);
bus_ofs, tmp_buf, FL_WRITING);
if (ret)
return ret;
@ -1579,7 +1632,7 @@ static int cfi_amdstd_write_words(struct mtd_info *mtd, loff_t to, size_t len,
datum = map_word_load(map, buf);
ret = do_write_oneword(map, &cfi->chips[chipnum],
ofs, datum);
ofs, datum, FL_WRITING);
if (ret)
return ret;
@ -1622,7 +1675,7 @@ static int cfi_amdstd_write_words(struct mtd_info *mtd, loff_t to, size_t len,
tmp_buf = map_word_load_partial(map, tmp_buf, buf, 0, len);
ret = do_write_oneword(map, &cfi->chips[chipnum],
ofs, tmp_buf);
ofs, tmp_buf, FL_WRITING);
if (ret)
return ret;