From: Tokunori Ikegami <ikegami.t@gmail.com>
To: miquel.raynal@bootlin.com
Cc: richard@nod.at, vigneshr@ti.com, linux-mtd@lists.infradead.org,
Tokunori Ikegami <ikegami.t@gmail.com>,
stable@vger.kernel.org
Subject: [PATCH v7 1/4] mtd: cfi_cmdset_0002: Move and rename chip_check/chip_ready/chip_good_for_write
Date: Thu, 24 Mar 2022 02:04:55 +0900 [thread overview]
Message-ID: <20220323170458.5608-2-ikegami.t@gmail.com> (raw)
In-Reply-To: <20220323170458.5608-1-ikegami.t@gmail.com>
This is a preparation patch for the S29GL064N buffer writes fix. There
is no functional change.
Fixes: dfeae1073583("mtd: cfi_cmdset_0002: Change write buffer to check correct value")
Signed-off-by: Tokunori Ikegami <ikegami.t@gmail.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/b687c259-6413-26c9-d4c9-b3afa69ea124@pengutronix.de/
---
drivers/mtd/chips/cfi_cmdset_0002.c | 95 ++++++++++-------------------
1 file changed, 32 insertions(+), 63 deletions(-)
diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index a761134fd3be..9ccde90dc180 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -802,21 +802,25 @@ static struct mtd_info *cfi_amdstd_setup(struct mtd_info *mtd)
}
/*
- * Return true if the chip is ready.
+ * Return true if the chip is ready and has the correct value.
*
* Ready is one of: read mode, query mode, erase-suspend-read mode (in any
* non-suspended sector) and is indicated by no toggle bits toggling.
*
+ * Error are indicated by toggling bits or bits held with the wrong value,
+ * or with bits toggling.
+ *
* Note that anything more complicated than checking if no bits are toggling
* (including checking DQ5 for an error status) is tricky to get working
* correctly and is therefore not done (particularly with interleaved chips
* as each chip must be checked independently of the others).
*/
static int __xipram chip_ready(struct map_info *map, struct flchip *chip,
- unsigned long addr)
+ unsigned long addr, map_word *expected)
{
struct cfi_private *cfi = map->fldrv_priv;
map_word d, t;
+ int ret;
if (cfi_use_status_reg(cfi)) {
map_word ready = CMD(CFI_SR_DRB);
@@ -826,57 +830,20 @@ static int __xipram chip_ready(struct map_info *map, struct flchip *chip,
*/
cfi_send_gen_cmd(0x70, cfi->addr_unlock1, chip->start, map, cfi,
cfi->device_type, NULL);
- d = map_read(map, addr);
+ t = map_read(map, addr);
- return map_word_andequal(map, d, ready, ready);
+ return map_word_andequal(map, t, ready, ready);
}
d = map_read(map, addr);
t = map_read(map, addr);
- return map_word_equal(map, d, t);
-}
-
-/*
- * Return true if the chip is ready and has the correct value.
- *
- * Ready is one of: read mode, query mode, erase-suspend-read mode (in any
- * non-suspended sector) and it is indicated by no bits toggling.
- *
- * Error are indicated by toggling bits or bits held with the wrong value,
- * or with bits toggling.
- *
- * Note that anything more complicated than checking if no bits are toggling
- * (including checking DQ5 for an error status) is tricky to get working
- * correctly and is therefore not done (particularly with interleaved chips
- * as each chip must be checked independently of the others).
- *
- */
-static int __xipram chip_good(struct map_info *map, struct flchip *chip,
- unsigned long addr, map_word expected)
-{
- struct cfi_private *cfi = map->fldrv_priv;
- map_word oldd, curd;
-
- if (cfi_use_status_reg(cfi)) {
- map_word ready = CMD(CFI_SR_DRB);
-
- /*
- * For chips that support status register, check device
- * ready bit
- */
- cfi_send_gen_cmd(0x70, cfi->addr_unlock1, chip->start, map, cfi,
- cfi->device_type, NULL);
- curd = map_read(map, addr);
-
- return map_word_andequal(map, curd, ready, ready);
- }
+ ret = map_word_equal(map, d, t);
- oldd = map_read(map, addr);
- curd = map_read(map, addr);
+ if (!ret || !expected)
+ return ret;
- return map_word_equal(map, oldd, curd) &&
- map_word_equal(map, curd, expected);
+ return map_word_equal(map, t, *expected);
}
static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr, int mode)
@@ -893,7 +860,7 @@ static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr
case FL_STATUS:
for (;;) {
- if (chip_ready(map, chip, adr))
+ if (chip_ready(map, chip, adr, NULL))
break;
if (time_after(jiffies, timeo)) {
@@ -932,7 +899,7 @@ static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr
chip->state = FL_ERASE_SUSPENDING;
chip->erase_suspended = 1;
for (;;) {
- if (chip_ready(map, chip, adr))
+ if (chip_ready(map, chip, adr, NULL))
break;
if (time_after(jiffies, timeo)) {
@@ -1463,7 +1430,7 @@ static int do_otp_lock(struct map_info *map, struct flchip *chip, loff_t adr,
/* wait for chip to become ready */
timeo = jiffies + msecs_to_jiffies(2);
for (;;) {
- if (chip_ready(map, chip, adr))
+ if (chip_ready(map, chip, adr, NULL))
break;
if (time_after(jiffies, timeo)) {
@@ -1695,11 +1662,11 @@ static int __xipram do_write_oneword_once(struct map_info *map,
}
/*
- * We check "time_after" and "!chip_good" before checking
- * "chip_good" to avoid the failure due to scheduling.
+ * We check "time_after" and "!chip_ready" before checking
+ * "chip_ready" to avoid the failure due to scheduling.
*/
if (time_after(jiffies, timeo) &&
- !chip_good(map, chip, adr, datum)) {
+ !chip_ready(map, chip, adr, &datum)) {
xip_enable(map, chip, adr);
printk(KERN_WARNING "MTD %s(): software timeout\n", __func__);
xip_disable(map, chip, adr);
@@ -1707,7 +1674,7 @@ static int __xipram do_write_oneword_once(struct map_info *map,
break;
}
- if (chip_good(map, chip, adr, datum)) {
+ if (chip_ready(map, chip, adr, &datum)) {
if (cfi_check_err_status(map, chip, adr))
ret = -EIO;
break;
@@ -1975,18 +1942,18 @@ static int __xipram do_write_buffer_wait(struct map_info *map,
}
/*
- * We check "time_after" and "!chip_good" before checking
- * "chip_good" to avoid the failure due to scheduling.
+ * We check "time_after" and "!chip_ready" before checking
+ * "chip_ready" to avoid the failure due to scheduling.
*/
if (time_after(jiffies, timeo) &&
- !chip_good(map, chip, adr, datum)) {
+ !chip_ready(map, chip, adr, &datum)) {
pr_err("MTD %s(): software timeout, address:0x%.8lx.\n",
__func__, adr);
ret = -EIO;
break;
}
- if (chip_good(map, chip, adr, datum)) {
+ if (chip_ready(map, chip, adr, &datum)) {
if (cfi_check_err_status(map, chip, adr))
ret = -EIO;
break;
@@ -2195,7 +2162,7 @@ static int cfi_amdstd_panic_wait(struct map_info *map, struct flchip *chip,
* If the driver thinks the chip is idle, and no toggle bits
* are changing, then the chip is actually idle for sure.
*/
- if (chip->state == FL_READY && chip_ready(map, chip, adr))
+ if (chip->state == FL_READY && chip_ready(map, chip, adr, NULL))
return 0;
/*
@@ -2212,7 +2179,7 @@ static int cfi_amdstd_panic_wait(struct map_info *map, struct flchip *chip,
/* wait for the chip to become ready */
for (i = 0; i < jiffies_to_usecs(timeo); i++) {
- if (chip_ready(map, chip, adr))
+ if (chip_ready(map, chip, adr, NULL))
return 0;
udelay(1);
@@ -2276,13 +2243,13 @@ static int do_panic_write_oneword(struct map_info *map, struct flchip *chip,
map_write(map, datum, adr);
for (i = 0; i < jiffies_to_usecs(uWriteTimeout); i++) {
- if (chip_ready(map, chip, adr))
+ if (chip_ready(map, chip, adr, NULL))
break;
udelay(1);
}
- if (!chip_good(map, chip, adr, datum) ||
+ if (!chip_ready(map, chip, adr, &datum) ||
cfi_check_err_status(map, chip, adr)) {
/* reset on all failures. */
map_write(map, CMD(0xF0), chip->start);
@@ -2424,6 +2391,7 @@ static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
DECLARE_WAITQUEUE(wait, current);
int ret;
int retry_cnt = 0;
+ map_word datum = map_word_ff(map);
adr = cfi->addr_unlock1;
@@ -2478,7 +2446,7 @@ static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
chip->erase_suspended = 0;
}
- if (chip_good(map, chip, adr, map_word_ff(map))) {
+ if (chip_ready(map, chip, adr, &datum)) {
if (cfi_check_err_status(map, chip, adr))
ret = -EIO;
break;
@@ -2523,6 +2491,7 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
DECLARE_WAITQUEUE(wait, current);
int ret;
int retry_cnt = 0;
+ map_word datum = map_word_ff(map);
adr += chip->start;
@@ -2577,7 +2546,7 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
chip->erase_suspended = 0;
}
- if (chip_good(map, chip, adr, map_word_ff(map))) {
+ if (chip_ready(map, chip, adr, &datum)) {
if (cfi_check_err_status(map, chip, adr))
ret = -EIO;
break;
@@ -2771,7 +2740,7 @@ static int __maybe_unused do_ppb_xxlock(struct map_info *map,
*/
timeo = jiffies + msecs_to_jiffies(2000); /* 2s max (un)locking */
for (;;) {
- if (chip_ready(map, chip, adr))
+ if (chip_ready(map, chip, adr, NULL))
break;
if (time_after(jiffies, timeo)) {
--
2.32.0
______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/
WARNING: multiple messages have this Message-ID (diff)
From: Tokunori Ikegami <ikegami.t@gmail.com>
To: miquel.raynal@bootlin.com
Cc: richard@nod.at, vigneshr@ti.com, linux-mtd@lists.infradead.org,
Tokunori Ikegami <ikegami.t@gmail.com>,
stable@vger.kernel.org
Subject: [PATCH v7 1/4] mtd: cfi_cmdset_0002: Move and rename chip_check/chip_ready/chip_good_for_write
Date: Thu, 24 Mar 2022 02:04:55 +0900 [thread overview]
Message-ID: <20220323170458.5608-2-ikegami.t@gmail.com> (raw)
In-Reply-To: <20220323170458.5608-1-ikegami.t@gmail.com>
This is a preparation patch for the S29GL064N buffer writes fix. There
is no functional change.
Fixes: dfeae1073583("mtd: cfi_cmdset_0002: Change write buffer to check correct value")
Signed-off-by: Tokunori Ikegami <ikegami.t@gmail.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/b687c259-6413-26c9-d4c9-b3afa69ea124@pengutronix.de/
---
drivers/mtd/chips/cfi_cmdset_0002.c | 95 ++++++++++-------------------
1 file changed, 32 insertions(+), 63 deletions(-)
diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index a761134fd3be..9ccde90dc180 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -802,21 +802,25 @@ static struct mtd_info *cfi_amdstd_setup(struct mtd_info *mtd)
}
/*
- * Return true if the chip is ready.
+ * Return true if the chip is ready and has the correct value.
*
* Ready is one of: read mode, query mode, erase-suspend-read mode (in any
* non-suspended sector) and is indicated by no toggle bits toggling.
*
+ * Error are indicated by toggling bits or bits held with the wrong value,
+ * or with bits toggling.
+ *
* Note that anything more complicated than checking if no bits are toggling
* (including checking DQ5 for an error status) is tricky to get working
* correctly and is therefore not done (particularly with interleaved chips
* as each chip must be checked independently of the others).
*/
static int __xipram chip_ready(struct map_info *map, struct flchip *chip,
- unsigned long addr)
+ unsigned long addr, map_word *expected)
{
struct cfi_private *cfi = map->fldrv_priv;
map_word d, t;
+ int ret;
if (cfi_use_status_reg(cfi)) {
map_word ready = CMD(CFI_SR_DRB);
@@ -826,57 +830,20 @@ static int __xipram chip_ready(struct map_info *map, struct flchip *chip,
*/
cfi_send_gen_cmd(0x70, cfi->addr_unlock1, chip->start, map, cfi,
cfi->device_type, NULL);
- d = map_read(map, addr);
+ t = map_read(map, addr);
- return map_word_andequal(map, d, ready, ready);
+ return map_word_andequal(map, t, ready, ready);
}
d = map_read(map, addr);
t = map_read(map, addr);
- return map_word_equal(map, d, t);
-}
-
-/*
- * Return true if the chip is ready and has the correct value.
- *
- * Ready is one of: read mode, query mode, erase-suspend-read mode (in any
- * non-suspended sector) and it is indicated by no bits toggling.
- *
- * Error are indicated by toggling bits or bits held with the wrong value,
- * or with bits toggling.
- *
- * Note that anything more complicated than checking if no bits are toggling
- * (including checking DQ5 for an error status) is tricky to get working
- * correctly and is therefore not done (particularly with interleaved chips
- * as each chip must be checked independently of the others).
- *
- */
-static int __xipram chip_good(struct map_info *map, struct flchip *chip,
- unsigned long addr, map_word expected)
-{
- struct cfi_private *cfi = map->fldrv_priv;
- map_word oldd, curd;
-
- if (cfi_use_status_reg(cfi)) {
- map_word ready = CMD(CFI_SR_DRB);
-
- /*
- * For chips that support status register, check device
- * ready bit
- */
- cfi_send_gen_cmd(0x70, cfi->addr_unlock1, chip->start, map, cfi,
- cfi->device_type, NULL);
- curd = map_read(map, addr);
-
- return map_word_andequal(map, curd, ready, ready);
- }
+ ret = map_word_equal(map, d, t);
- oldd = map_read(map, addr);
- curd = map_read(map, addr);
+ if (!ret || !expected)
+ return ret;
- return map_word_equal(map, oldd, curd) &&
- map_word_equal(map, curd, expected);
+ return map_word_equal(map, t, *expected);
}
static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr, int mode)
@@ -893,7 +860,7 @@ static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr
case FL_STATUS:
for (;;) {
- if (chip_ready(map, chip, adr))
+ if (chip_ready(map, chip, adr, NULL))
break;
if (time_after(jiffies, timeo)) {
@@ -932,7 +899,7 @@ static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr
chip->state = FL_ERASE_SUSPENDING;
chip->erase_suspended = 1;
for (;;) {
- if (chip_ready(map, chip, adr))
+ if (chip_ready(map, chip, adr, NULL))
break;
if (time_after(jiffies, timeo)) {
@@ -1463,7 +1430,7 @@ static int do_otp_lock(struct map_info *map, struct flchip *chip, loff_t adr,
/* wait for chip to become ready */
timeo = jiffies + msecs_to_jiffies(2);
for (;;) {
- if (chip_ready(map, chip, adr))
+ if (chip_ready(map, chip, adr, NULL))
break;
if (time_after(jiffies, timeo)) {
@@ -1695,11 +1662,11 @@ static int __xipram do_write_oneword_once(struct map_info *map,
}
/*
- * We check "time_after" and "!chip_good" before checking
- * "chip_good" to avoid the failure due to scheduling.
+ * We check "time_after" and "!chip_ready" before checking
+ * "chip_ready" to avoid the failure due to scheduling.
*/
if (time_after(jiffies, timeo) &&
- !chip_good(map, chip, adr, datum)) {
+ !chip_ready(map, chip, adr, &datum)) {
xip_enable(map, chip, adr);
printk(KERN_WARNING "MTD %s(): software timeout\n", __func__);
xip_disable(map, chip, adr);
@@ -1707,7 +1674,7 @@ static int __xipram do_write_oneword_once(struct map_info *map,
break;
}
- if (chip_good(map, chip, adr, datum)) {
+ if (chip_ready(map, chip, adr, &datum)) {
if (cfi_check_err_status(map, chip, adr))
ret = -EIO;
break;
@@ -1975,18 +1942,18 @@ static int __xipram do_write_buffer_wait(struct map_info *map,
}
/*
- * We check "time_after" and "!chip_good" before checking
- * "chip_good" to avoid the failure due to scheduling.
+ * We check "time_after" and "!chip_ready" before checking
+ * "chip_ready" to avoid the failure due to scheduling.
*/
if (time_after(jiffies, timeo) &&
- !chip_good(map, chip, adr, datum)) {
+ !chip_ready(map, chip, adr, &datum)) {
pr_err("MTD %s(): software timeout, address:0x%.8lx.\n",
__func__, adr);
ret = -EIO;
break;
}
- if (chip_good(map, chip, adr, datum)) {
+ if (chip_ready(map, chip, adr, &datum)) {
if (cfi_check_err_status(map, chip, adr))
ret = -EIO;
break;
@@ -2195,7 +2162,7 @@ static int cfi_amdstd_panic_wait(struct map_info *map, struct flchip *chip,
* If the driver thinks the chip is idle, and no toggle bits
* are changing, then the chip is actually idle for sure.
*/
- if (chip->state == FL_READY && chip_ready(map, chip, adr))
+ if (chip->state == FL_READY && chip_ready(map, chip, adr, NULL))
return 0;
/*
@@ -2212,7 +2179,7 @@ static int cfi_amdstd_panic_wait(struct map_info *map, struct flchip *chip,
/* wait for the chip to become ready */
for (i = 0; i < jiffies_to_usecs(timeo); i++) {
- if (chip_ready(map, chip, adr))
+ if (chip_ready(map, chip, adr, NULL))
return 0;
udelay(1);
@@ -2276,13 +2243,13 @@ static int do_panic_write_oneword(struct map_info *map, struct flchip *chip,
map_write(map, datum, adr);
for (i = 0; i < jiffies_to_usecs(uWriteTimeout); i++) {
- if (chip_ready(map, chip, adr))
+ if (chip_ready(map, chip, adr, NULL))
break;
udelay(1);
}
- if (!chip_good(map, chip, adr, datum) ||
+ if (!chip_ready(map, chip, adr, &datum) ||
cfi_check_err_status(map, chip, adr)) {
/* reset on all failures. */
map_write(map, CMD(0xF0), chip->start);
@@ -2424,6 +2391,7 @@ static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
DECLARE_WAITQUEUE(wait, current);
int ret;
int retry_cnt = 0;
+ map_word datum = map_word_ff(map);
adr = cfi->addr_unlock1;
@@ -2478,7 +2446,7 @@ static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
chip->erase_suspended = 0;
}
- if (chip_good(map, chip, adr, map_word_ff(map))) {
+ if (chip_ready(map, chip, adr, &datum)) {
if (cfi_check_err_status(map, chip, adr))
ret = -EIO;
break;
@@ -2523,6 +2491,7 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
DECLARE_WAITQUEUE(wait, current);
int ret;
int retry_cnt = 0;
+ map_word datum = map_word_ff(map);
adr += chip->start;
@@ -2577,7 +2546,7 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
chip->erase_suspended = 0;
}
- if (chip_good(map, chip, adr, map_word_ff(map))) {
+ if (chip_ready(map, chip, adr, &datum)) {
if (cfi_check_err_status(map, chip, adr))
ret = -EIO;
break;
@@ -2771,7 +2740,7 @@ static int __maybe_unused do_ppb_xxlock(struct map_info *map,
*/
timeo = jiffies + msecs_to_jiffies(2000); /* 2s max (un)locking */
for (;;) {
- if (chip_ready(map, chip, adr))
+ if (chip_ready(map, chip, adr, NULL))
break;
if (time_after(jiffies, timeo)) {
--
2.32.0
next prev parent reply other threads:[~2022-03-23 17:05 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-23 17:04 [PATCH v7 0/4] mtd: cfi_cmdset_0002: Use chip_ready() for write on S29GL064N Tokunori Ikegami
2022-03-23 17:04 ` Tokunori Ikegami
2022-03-23 17:04 ` Tokunori Ikegami [this message]
2022-03-23 17:04 ` [PATCH v7 1/4] mtd: cfi_cmdset_0002: Move and rename chip_check/chip_ready/chip_good_for_write Tokunori Ikegami
2022-04-28 8:18 ` Miquel Raynal
2022-04-28 8:18 ` Miquel Raynal
2022-03-23 17:04 ` [PATCH v7 2/4] mtd: cfi_cmdset_0002: Use chip_ready() for write on S29GL064N Tokunori Ikegami
2022-03-23 17:04 ` Tokunori Ikegami
2022-04-28 8:18 ` Miquel Raynal
2022-04-28 8:18 ` Miquel Raynal
2022-03-23 17:04 ` [PATCH v7 3/4] mtd: cfi_cmdset_0002: Add S29GL064N ID definition Tokunori Ikegami
2022-04-28 8:18 ` Miquel Raynal
2022-03-23 17:04 ` [PATCH v7 4/4] mtd: cfi_cmdset_0002: Rename chip_ready variables Tokunori Ikegami
2022-04-28 8:18 ` Miquel Raynal
2022-03-28 10:50 ` [PATCH v7 0/4] mtd: cfi_cmdset_0002: Use chip_ready() for write on S29GL064N Ahmad Fatoum
2022-03-28 10:50 ` Ahmad Fatoum
2022-03-28 15:31 ` Tokunori Ikegami
2022-03-28 15:31 ` Tokunori Ikegami
2022-04-10 8:51 ` Thorsten Leemhuis
2022-04-10 8:51 ` Thorsten Leemhuis
2022-04-11 7:40 ` Miquel Raynal
2022-04-11 7:40 ` Miquel Raynal
2022-04-27 9:37 ` Miquel Raynal
2022-04-27 9:37 ` Miquel Raynal
2022-04-28 6:32 ` Vignesh Raghavendra
2022-04-28 6:32 ` Vignesh Raghavendra
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