old mode 100644
new mode 100755
@@ -1627,29 +1627,31 @@ static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
continue;
}
- if (time_after(jiffies, timeo) && !chip_ready(map, adr)){
+ if (chip_good(map, adr, datum))
+ break;
+
+ if (time_after(jiffies, timeo)){
xip_enable(map, chip, adr);
printk(KERN_WARNING "MTD %s(): software timeout\n", __func__);
xip_disable(map, chip, adr);
+ ret = -EIO;
break;
}
- if (chip_ready(map, adr))
- break;
-
/* Latency issues. Drop the lock, wait a while and retry */
UDELAY(map, chip, adr, 1);
}
+
/* Did we succeed? */
- if (!chip_good(map, adr, datum)) {
+ if (ret) {
/* reset on all failures. */
map_write(map, CMD(0xF0), chip->start);
/* FIXME - should have reset delay before continuing */
- if (++retry_cnt <= MAX_RETRIES)
+ if (++retry_cnt <= MAX_RETRIES) {
+ ret = 0;
goto retry;
-
- ret = -EIO;
+ }
}
xip_enable(map, chip, adr);
op_done:
As reported by the OpenWRT team, write requests sometimes fail on some platforms. Currently to check the state chip_ready() is used correctly as described by the flash memory S29GL256P11TFI01 datasheet. Also chip_good() is used to check if the write is succeeded and it was implemented by the commit fb4a90bfcd6d8 ("[MTD] CFI-0002 - Improve error checking"). But actually the write failure is caused on some platforms and also it can be fixed by using chip_good() to check the state and retry instead. Also it seems that it is caused after repeated about 1,000 times to retry the write one word with the reset command. By using chip_good() to check the state to be done it can be reduced the retry with reset. It is depended on the actual flash chip behavior so the root cause is unknown. Signed-off-by: Tokunori Ikegami <ikegami_to@yahoo.co.jp> Signed-off-by: Felix Fietkau <nbd@nbd.name> Co-Developed-by: Hauke Mehrtens <hauke@hauke-m.de> Co-Developed-by: Koen Vandeputte <koen.vandeputte@ncentric.com> Reported-by: Fabio Bettoni <fbettoni@gmail.com> Cc: Chris Packham <chris.packham@alliedtelesis.co.nz> Cc: Joakim Tjernlund <Joakim.Tjernlund@infinera.com> Cc: linux-mtd@lists.infradead.org Cc: stable@vger.kernel.org --- Changes since v4: - None. Changes since v3: - Update the commit message for the comments. - Drop the addition of blanks lines around xip_enable(). - Delete unnecessary setting the ret variable to -EIO. - Change the email address of Tokunori Ikegami to ikegami_to@yahoo.co.jp. Changes since v2: - Just update the commit message for the comment. Changes since v1: - Just update the commit message. Background: This is required for OpenWrt Project to result the flash write issue as below patche. <https://git.openwrt.org/?p=openwrt/openwrt.git;a=commitdiff;h=ddc11c3932c7b7b7df7d5fbd48f207e77619eaa7> Also the original patch in OpenWRT is below. <https://github.com/openwrt/openwrt/blob/v18.06.0/target/linux/ar71xx/patches-4.9/403-mtd_fix_cfi_cmdset_0002_status_check.patch> The reason to use chip_good() is that just actually fix the issue. And also in the past I had fixed the erase function also as same way by the patch below. <https://patchwork.ozlabs.org/patch/922656/> Note: The reason for the patch for erase is same. In my understanding the chip_ready() is just checked the value twice from flash. So I think that sometimes incorrect value is read twice and it is depended on the flash device behavior but not sure.. So change to use chip_good() instead of chip_ready(). drivers/mtd/chips/cfi_cmdset_0002.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) mode change 100644 => 100755 drivers/mtd/chips/cfi_cmdset_0002.c