Commit 4f5cb243 authored by Christian Riesch's avatar Christian Riesch Committed by Brian Norris

mtd: cfi_cmdset_0002: Add support for locking OTP memory

This patch adds support for the locking of the one time
programmable (OTP) memory of Micron M29EW devices.
Signed-off-by: default avatarChristian Riesch <christian.riesch@omicron.at>
Signed-off-by: default avatarBrian Norris <computersforpeace@gmail.com>
parent af744750
......@@ -69,6 +69,7 @@ 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_lock_user_prot_reg(struct mtd_info *, loff_t, size_t);
static int cfi_amdstd_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const u_char *buf);
......@@ -533,6 +534,7 @@ struct mtd_info *cfi_cmdset_0002(struct map_info *map, int primary)
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->_lock_user_prot_reg = cfi_amdstd_lock_user_prot_reg;
mtd->flags = MTD_CAP_NORFLASH;
mtd->name = map->name;
mtd->writesize = 1;
......@@ -1153,7 +1155,7 @@ static int cfi_amdstd_read (struct mtd_info *mtd, loff_t from, size_t len, size_
}
typedef int (*otp_op_t)(struct map_info *map, struct flchip *chip,
loff_t adr, size_t len, u_char *buf);
loff_t adr, size_t len, u_char *buf, size_t grouplen);
static inline void otp_enter(struct map_info *map, struct flchip *chip,
loff_t adr, size_t len)
......@@ -1187,7 +1189,10 @@ static inline void otp_exit(struct map_info *map, struct flchip *chip,
INVALIDATE_CACHED_RANGE(map, chip->start + adr, len);
}
static inline int do_read_secsi_onechip(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,
size_t grouplen)
{
DECLARE_WAITQUEUE(wait, current);
unsigned long timeo = jiffies + HZ;
......@@ -1246,7 +1251,8 @@ static int cfi_amdstd_secsi_read (struct mtd_info *mtd, loff_t from, size_t len,
else
thislen = len;
ret = do_read_secsi_onechip(map, &cfi->chips[chipnum], ofs, thislen, buf);
ret = do_read_secsi_onechip(map, &cfi->chips[chipnum], ofs,
thislen, buf, 0);
if (ret)
break;
......@@ -1265,7 +1271,7 @@ static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
int mode);
static int do_otp_write(struct map_info *map, struct flchip *chip, loff_t adr,
size_t len, u_char *buf)
size_t len, u_char *buf, size_t grouplen)
{
int ret;
while (len) {
......@@ -1294,6 +1300,70 @@ static int do_otp_write(struct map_info *map, struct flchip *chip, loff_t adr,
return 0;
}
static int do_otp_lock(struct map_info *map, struct flchip *chip, loff_t adr,
size_t len, u_char *buf, size_t grouplen)
{
struct cfi_private *cfi = map->fldrv_priv;
uint8_t lockreg;
unsigned long timeo;
int ret;
/* make sure area matches group boundaries */
if ((adr != 0) || (len != grouplen))
return -EINVAL;
mutex_lock(&chip->mutex);
ret = get_chip(map, chip, chip->start, FL_LOCKING);
if (ret) {
mutex_unlock(&chip->mutex);
return ret;
}
chip->state = 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);
/* set bit 0 to protect extended memory block */
lockreg &= ~0x01;
/* set bit 0 to protect extended memory block */
/* write lock register */
map_write(map, CMD(0xA0), chip->start);
map_write(map, CMD(lockreg), chip->start);
/* wait for chip to become ready */
timeo = jiffies + msecs_to_jiffies(2);
for (;;) {
if (chip_ready(map, adr))
break;
if (time_after(jiffies, timeo)) {
pr_err("Waiting for chip to be ready timed out.\n");
ret = -EIO;
break;
}
UDELAY(map, chip, 0, 1);
}
/* exit protection commands */
map_write(map, CMD(0x90), chip->start);
map_write(map, CMD(0x00), chip->start);
chip->state = FL_READY;
put_chip(map, chip, chip->start);
mutex_unlock(&chip->mutex);
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)
......@@ -1392,7 +1462,8 @@ static int cfi_amdstd_otp_walk(struct mtd_info *mtd, loff_t from, size_t len,
} else if ((from < otpsize) && (len > 0)) {
size_t size;
size = (len < otpsize - from) ? len : otpsize - from;
ret = action(map, chip, otpoffset + from, size, buf);
ret = action(map, chip, otpoffset + from, size, buf,
otpsize);
if (ret < 0)
return ret;
......@@ -1445,6 +1516,14 @@ static int cfi_amdstd_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
do_otp_write, 1);
}
static int cfi_amdstd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
size_t len)
{
size_t retlen;
return cfi_amdstd_otp_walk(mtd, from, len, &retlen, NULL,
do_otp_lock, 1);
}
static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
unsigned long adr, map_word datum,
int mode)
......
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