1 files changed, 36 insertions, 0 deletions

diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index a972cc6be436..db16b7b0723f 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -13,6 +13,8 @@
  * XIP support hooks by Vitaly Wool (based on code for Intel flash
  * by Nicolas Pitre)
  *
+ * 25/09/2008 Christopher Moore: TopBottom fixup for many Macronix with CFI V1.0
+ *
  * Occasionally maintained by Thayne Harbaugh tharbaugh at lnxi dot com
  *
  * This code is GPL
@@ -43,6 +45,7 @@
 
 #define MANUFACTURER_AMD        0x0001
 #define MANUFACTURER_ATMEL      0x001F
+#define MANUFACTURER_MACRONIX   0x00C2
 #define MANUFACTURER_SST        0x00BF
 #define SST49LF004B             0x0060
 #define SST49LF040B             0x0050
@@ -144,12 +147,44 @@ static void fixup_amd_bootblock(struct mtd_info *mtd, void* param)
 
         if (((major << 8) | minor) < 0x3131) {
                 /* CFI version 1.0 => don't trust bootloc */
+
+                DEBUG(MTD_DEBUG_LEVEL1,
+                        "%s: JEDEC Vendor ID is 0x%02X Device ID is 0x%02X\n",
+                        map->name, cfi->mfr, cfi->id);
+
+                /* AFAICS all 29LV400 with a bottom boot block have a device ID
+                 * of 0x22BA in 16-bit mode and 0xBA in 8-bit mode.
+                 * These were badly detected as they have the 0x80 bit set
+                 * so treat them as a special case.
+                 */
+                if (((cfi->id == 0xBA) || (cfi->id == 0x22BA)) &&
+
+                        /* Macronix added CFI to their 2nd generation
+                         * MX29LV400C B/T but AFAICS no other 29LV400 (AMD,
+                         * Fujitsu, Spansion, EON, ESI and older Macronix)
+                         * has CFI.
+                         *
+                         * Therefore also check the manufacturer.
+                         * This reduces the risk of false detection due to
+                         * the 8-bit device ID.
+                         */
+                        (cfi->mfr == MANUFACTURER_MACRONIX)) {
+                        DEBUG(MTD_DEBUG_LEVEL1,
+                                "%s: Macronix MX29LV400C with bottom boot block"
+                                " detected\n", map->name);
+                        extp->TopBottom = 2;    /* bottom boot */
+                } else
                 if (cfi->id & 0x80) {
                         printk(KERN_WARNING "%s: JEDEC Device ID is 0x%02X. Assuming broken CFI table.\n", map->name, cfi->id);
                         extp->TopBottom = 3;    /* top boot */
                 } else {
                         extp->TopBottom = 2;    /* bottom boot */
                 }
+
+                DEBUG(MTD_DEBUG_LEVEL1,
+                        "%s: AMD CFI PRI V%c.%c has no boot block field;"
+                        " deduced %s from Device ID\n", map->name, major, minor,
+                        extp->TopBottom == 2 ? "bottom" : "top");
         }
 }
 #endif
@@ -243,6 +278,7 @@ static struct cfi_fixup cfi_fixup_table[] = {
         { CFI_MFR_ATMEL, CFI_ID_ANY, fixup_convert_atmel_pri, NULL },
 #ifdef AMD_BOOTLOC_BUG
         { CFI_MFR_AMD, CFI_ID_ANY, fixup_amd_bootblock, NULL },
+        { MANUFACTURER_MACRONIX, CFI_ID_ANY, fixup_amd_bootblock, NULL },
 #endif
         { CFI_MFR_AMD, 0x0050, fixup_use_secsi, NULL, },
         { CFI_MFR_AMD, 0x0053, fixup_use_secsi, NULL, },