From fb4a90bfcd6d86e8531073c42fae7fde40974f5d Mon Sep 17 00:00:00 2001 From: "Eric W. Biedermann" Date: Fri, 20 May 2005 04:28:26 +0100 Subject: [PATCH] [MTD] CFI-0002 - Improve error checking Check for errors besides infinite loops when writing and erasing. Signed-off-by: Eric W. Biederman Signed-off-by: Thomas Gleixner --- drivers/mtd/chips/cfi_cmdset_0002.c | 99 +++++++++++++++++++---------- 1 file changed, 67 insertions(+), 32 deletions(-) diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c index fca8ff6f7e1..59849236f52 100644 --- a/drivers/mtd/chips/cfi_cmdset_0002.c +++ b/drivers/mtd/chips/cfi_cmdset_0002.c @@ -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__); - - /* 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; + if (++retry_cnt <= MAX_WORD_RETRIES) + goto retry; - ret = -EIO; + ret = -EIO; + } op_done: chip->state = FL_READY; put_chip(map, chip, adr); @@ -1187,10 +1218,13 @@ static inline int do_erase_chip(struct map_info *map, struct flchip *chip) } 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); @@ -1198,16 +1232,15 @@ static inline int do_erase_chip(struct map_info *map, struct flchip *chip) 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__ ); - - /* 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); @@ -1272,10 +1305,13 @@ static inline int do_erase_oneblock(struct map_info *map, struct flchip *chip, u } 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); @@ -1283,16 +1319,15 @@ static inline int do_erase_oneblock(struct map_info *map, struct flchip *chip, u 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); -- 2.41.0