mtd: cfi_cmdset_0002: Add support for reading OTP

The Micron M29EW has a 256 byte one time programmable (OTP) memory.
This patch adds support for reading this memory. This support will be
extended for locking and writing in subsequent patches.

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 13:18:27 +01:00 коммит произвёл Brian Norris
Родитель c14deddec1
Коммит dc7e9ecdd6
1 изменённых файлов: 156 добавлений и 0 удалений

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@ -58,7 +58,15 @@ static void cfi_amdstd_sync (struct mtd_info *);
static int cfi_amdstd_suspend (struct mtd_info *);
static void cfi_amdstd_resume (struct mtd_info *);
static int cfi_amdstd_reboot(struct notifier_block *, unsigned long, void *);
static int cfi_amdstd_get_fact_prot_info(struct mtd_info *, size_t,
size_t *, struct otp_info *);
static int cfi_amdstd_get_user_prot_info(struct mtd_info *, size_t,
size_t *, struct otp_info *);
static int cfi_amdstd_secsi_read (struct mtd_info *, loff_t, size_t, size_t *, u_char *);
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_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const u_char *buf);
@ -518,6 +526,10 @@ struct mtd_info *cfi_cmdset_0002(struct map_info *map, int primary)
mtd->_sync = cfi_amdstd_sync;
mtd->_suspend = cfi_amdstd_suspend;
mtd->_resume = cfi_amdstd_resume;
mtd->_read_user_prot_reg = cfi_amdstd_read_user_prot_reg;
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->flags = MTD_CAP_NORFLASH;
mtd->name = map->name;
mtd->writesize = 1;
@ -1137,6 +1149,8 @@ static int cfi_amdstd_read (struct mtd_info *mtd, loff_t from, size_t len, size_
return ret;
}
typedef int (*otp_op_t)(struct map_info *map, struct flchip *chip,
loff_t adr, size_t len, u_char *buf);
static inline int do_read_secsi_onechip(struct map_info *map, struct flchip *chip, loff_t adr, size_t len, u_char *buf)
{
@ -1219,6 +1233,148 @@ static int cfi_amdstd_secsi_read (struct mtd_info *mtd, loff_t from, size_t len,
return ret;
}
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)
{
struct map_info *map = mtd->priv;
struct cfi_private *cfi = map->fldrv_priv;
int ofs_factor = cfi->interleave * cfi->device_type;
unsigned long base;
int chipnum;
struct flchip *chip;
uint8_t otp, lockreg;
int ret;
size_t user_size, factory_size, otpsize;
loff_t user_offset, factory_offset, otpoffset;
int user_locked = 0, otplocked;
*retlen = 0;
for (chipnum = 0; chipnum < cfi->numchips; chipnum++) {
chip = &cfi->chips[chipnum];
factory_size = 0;
user_size = 0;
/* Micron M29EW family */
if (is_m29ew(cfi)) {
base = chip->start;
/* check whether secsi area is factory locked
or user lockable */
mutex_lock(&chip->mutex);
ret = get_chip(map, chip, base, FL_CFI_QUERY);
if (ret) {
mutex_unlock(&chip->mutex);
return ret;
}
cfi_qry_mode_on(base, map, cfi);
otp = cfi_read_query(map, base + 0x3 * ofs_factor);
cfi_qry_mode_off(base, map, cfi);
put_chip(map, chip, base);
mutex_unlock(&chip->mutex);
if (otp & 0x80) {
/* factory locked */
factory_offset = 0;
factory_size = 0x100;
} else {
/* customer lockable */
user_offset = 0;
user_size = 0x100;
mutex_lock(&chip->mutex);
ret = get_chip(map, chip, base, FL_LOCKING);
/* Enter lock register command */
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(0x40, cfi->addr_unlock1,
chip->start, map, cfi,
cfi->device_type, NULL);
/* read lock register */
lockreg = cfi_read_query(map, 0);
/* exit protection commands */
map_write(map, CMD(0x90), chip->start);
map_write(map, CMD(0x00), chip->start);
put_chip(map, chip, chip->start);
mutex_unlock(&chip->mutex);
user_locked = ((lockreg & 0x01) == 0x00);
}
}
otpsize = user_regs ? user_size : factory_size;
if (!otpsize)
continue;
otpoffset = user_regs ? user_offset : factory_offset;
otplocked = user_regs ? user_locked : 1;
if (!action) {
/* return otpinfo */
struct otp_info *otpinfo;
len -= sizeof(*otpinfo);
if (len <= 0)
return -ENOSPC;
otpinfo = (struct otp_info *)buf;
otpinfo->start = from;
otpinfo->length = otpsize;
otpinfo->locked = otplocked;
buf += sizeof(*otpinfo);
*retlen += sizeof(*otpinfo);
from += otpsize;
} else if ((from < otpsize) && (len > 0)) {
size_t size;
size = (len < otpsize - from) ? len : otpsize - from;
ret = action(map, chip, otpoffset + from, size, buf);
if (ret < 0)
return ret;
buf += size;
len -= size;
*retlen += size;
from = 0;
} else {
from -= otpsize;
}
}
return 0;
}
static int cfi_amdstd_get_fact_prot_info(struct mtd_info *mtd, size_t len,
size_t *retlen, struct otp_info *buf)
{
return cfi_amdstd_otp_walk(mtd, 0, len, retlen, (u_char *)buf,
NULL, 0);
}
static int cfi_amdstd_get_user_prot_info(struct mtd_info *mtd, size_t len,
size_t *retlen, struct otp_info *buf)
{
return cfi_amdstd_otp_walk(mtd, 0, len, retlen, (u_char *)buf,
NULL, 1);
}
static int cfi_amdstd_read_fact_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_read_secsi_onechip, 0);
}
static int cfi_amdstd_read_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_read_secsi_onechip, 1);
}
static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip, unsigned long adr, map_word datum)
{