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[MTD] CFI-0002 - Improve error checking 

Check for errors besides infinite loops when writing and erasing.

Signed-off-by: Eric W. Biederman <ebiederman@lnxi.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Eric W. Biedermann 2005-05-20 04:28:26 +01:00 committed by Thomas Gleixner
parent 6da70124a1
commit fb4a90bfcd
1 changed files with 69 additions and 34 deletions
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103
drivers/mtd/chips/cfi_cmdset_0002.c
View File

@ -13,7 +13,7 @@
*
* This code is GPL
*
* $Id: cfi_cmdset_0002.c,v 1.114 2004/12/11 15:43:53 dedekind Exp $
* $Id: cfi_cmdset_0002.c,v 1.115 2005/05/20 03:28:23 eric Exp $
*
*/
@ -43,6 +43,7 @@
#define MANUFACTURER_AMD 0x0001
#define MANUFACTURER_SST 0x00BF
#define SST49LF004B 0x0060
#define SST49LF008A 0x005a
static int cfi_amdstd_read (struct mtd_info *, loff_t, size_t, size_t *, u_char *);
static int cfi_amdstd_write_words(struct mtd_info *, loff_t, size_t, size_t *, const u_char *);
@ -191,6 +192,7 @@ static struct cfi_fixup cfi_fixup_table[] = {
};
static struct cfi_fixup jedec_fixup_table[] = {
{ MANUFACTURER_SST, SST49LF004B, fixup_use_fwh_lock, NULL, },
{ MANUFACTURER_SST, SST49LF008A, fixup_use_fwh_lock, NULL, },
{ 0, 0, NULL, NULL }
};
@ -401,6 +403,32 @@ static int chip_ready(struct map_info *map, unsigned long 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 (particulary with interleaved chips
* as each chip must be checked independantly of the others).
*
*/
static int chip_good(struct map_info *map, unsigned long addr, map_word expected)
{
map_word oldd, curd;
oldd = map_read(map, addr);
curd = map_read(map, addr);
return map_word_equal(map, oldd, curd) &&
map_word_equal(map, curd, expected);
}
static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr, int mode)
{
DECLARE_WAITQUEUE(wait, current);
@ -765,26 +793,29 @@ static int do_write_oneword(struct map_info *map, struct flchip *chip, unsigned
}
if (chip_ready(map, adr))
goto op_done;
break;
if (time_after(jiffies, timeo))
if (time_after(jiffies, timeo)) {
printk(KERN_WARNING "MTD %s(): software timeout\n", __func__);
break;
}
/* Latency issues. Drop the lock, wait a while and retry */
cfi_spin_unlock(chip->mutex);
cfi_udelay(1);
cfi_spin_lock(chip->mutex);
}
/* Did we succeed? */
if (!chip_good(map, adr, datum)) {
/* reset on all failures. */
map_write( map, CMD(0xF0), chip->start );
/* FIXME - should have reset delay before continuing */
printk(KERN_WARNING "MTD %s(): software timeout\n", __func__);
if (++retry_cnt <= MAX_WORD_RETRIES)
goto retry;
/* reset on all failures. */
map_write( map, CMD(0xF0), chip->start );
/* FIXME - should have reset delay before continuing */
if (++retry_cnt <= MAX_WORD_RETRIES)
goto retry;
ret = -EIO;
ret = -EIO;
}
op_done:
chip->state = FL_READY;
put_chip(map, chip, adr);
@ -1187,27 +1218,29 @@ static inline int do_erase_chip(struct map_info *map, struct flchip *chip)
}
if (chip_ready(map, adr))
goto op_done;
if (time_after(jiffies, timeo))
break;
if (time_after(jiffies, timeo)) {
printk(KERN_WARNING "MTD %s(): software timeout\n",
__func__ );
break;
}
/* Latency issues. Drop the lock, wait a while and retry */
cfi_spin_unlock(chip->mutex);
set_current_state(TASK_UNINTERRUPTIBLE);
schedule_timeout(1);
cfi_spin_lock(chip->mutex);
}
/* Did we succeed? */
if (!chip_good(map, adr, map_word_ff(map))) {
/* reset on all failures. */
map_write( map, CMD(0xF0), chip->start );
/* FIXME - should have reset delay before continuing */
printk(KERN_WARNING "MTD %s(): software timeout\n",
__func__ );
ret = -EIO;
}
/* reset on all failures. */
map_write( map, CMD(0xF0), chip->start );
/* FIXME - should have reset delay before continuing */
ret = -EIO;
op_done:
chip->state = FL_READY;
put_chip(map, chip, adr);
cfi_spin_unlock(chip->mutex);
@ -1272,27 +1305,29 @@ static inline int do_erase_oneblock(struct map_info *map, struct flchip *chip, u
}
if (chip_ready(map, adr))
goto op_done;
if (time_after(jiffies, timeo))
break;
if (time_after(jiffies, timeo)) {
printk(KERN_WARNING "MTD %s(): software timeout\n",
__func__ );
break;
}
/* Latency issues. Drop the lock, wait a while and retry */
cfi_spin_unlock(chip->mutex);
set_current_state(TASK_UNINTERRUPTIBLE);
schedule_timeout(1);
cfi_spin_lock(chip->mutex);
}
printk(KERN_WARNING "MTD %s(): software timeout\n",
__func__ );
/* reset on all failures. */
map_write( map, CMD(0xF0), chip->start );
/* FIXME - should have reset delay before continuing */
/* Did we succeed? */
if (chip_good(map, adr, map_word_ff(map))) {
/* reset on all failures. */
map_write( map, CMD(0xF0), chip->start );
/* FIXME - should have reset delay before continuing */
ret = -EIO;
}
ret = -EIO;
op_done:
chip->state = FL_READY;
put_chip(map, chip, adr);
cfi_spin_unlock(chip->mutex);