[RESEND PATCH v4 4/4] mtd: cfi_cmdset_0002: Add support for locking OTP memory
Christian Riesch
christian.riesch at omicron.at
Sun May 4 23:14:29 PDT 2014
This patch adds support for the locking of the one time
programmable (OTP) memory of Micron M29EW devices.
Signed-off-by: Christian Riesch <christian.riesch at omicron.at>
---
drivers/mtd/chips/cfi_cmdset_0002.c | 89 +++++++++++++++++++++++++++++++++--
1 file changed, 84 insertions(+), 5 deletions(-)
diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index 5d446f8..ac79010 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -70,6 +70,7 @@ 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);
@@ -536,6 +537,7 @@ 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;
@@ -1158,7 +1160,7 @@ 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)
@@ -1192,7 +1194,10 @@ 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;
@@ -1251,7 +1256,8 @@ 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;
@@ -1270,7 +1276,7 @@ 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) {
@@ -1299,6 +1305,70 @@ 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)
@@ -1397,7 +1467,8 @@ 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;
@@ -1450,6 +1521,14 @@ 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)
--
1.7.9.5
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