[PATCH] support for broken EON chips

[Koen Martens <gmc@sonologic.nl>]

Ok, here goes nothing. Go ahead, kill me :)

Comments very welcome, since i don't have a clue atm about how to do this nicely. If all goes well i might have some time to add more EON chips to jedec_probe soon. The patch below is against cvs..



diff -Naur mtd-orig/drivers/mtd/chips/cfi_probe.c mtd/drivers/mtd/chips/cfi_probe.c
--- mtd-orig/drivers/mtd/chips/cfi_probe.c	2004-11-16 19:19:02.000000000 +0100
+++ mtd/drivers/mtd/chips/cfi_probe.c	2005-07-05 15:35:19.000000000 +0200
@@ -231,7 +231,19 @@
 	cfi_send_gen_cmd(0x55, 0x2aa, base, map, cfi, cfi->device_type, NULL);
 	cfi_send_gen_cmd(0x90, 0x555, base, map, cfi, cfi->device_type, NULL);
 	cfi->mfr = cfi_read_query(map, base);
+#ifdef CONFIG_MTD_EON
+        if(cfi->mfr==0x7f) {
+          cfi->mfr = cfi_read_query(map, base + (0x100*ofs_factor));
+        }
+#endif  
 	cfi->id = cfi_read_query(map, base + ofs_factor);    
+#ifdef CONFIG_MTD_EON
+        if(cfi->mfr==0x1c && (cfi->id==0xb9 || cfi->id==0xba)) {
+          kfree(cfi->cfiq);
+          return 0;
+        }
+#endif  
+
 
 	/* Put it back into Read Mode */
 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
diff -Naur mtd-orig/drivers/mtd/chips/jedec_probe.c mtd/drivers/mtd/chips/jedec_probe.c
--- mtd-orig/drivers/mtd/chips/jedec_probe.c	2005-03-17 21:09:51.000000000 +0100
+++ mtd/drivers/mtd/chips/jedec_probe.c	2005-07-05 15:32:33.000000000 +0200
@@ -38,6 +38,7 @@
 #define MANUFACTURER_ST		0x0020
 #define MANUFACTURER_TOSHIBA	0x0098
 #define MANUFACTURER_WINBOND	0x00da
+#define MANUFACTURER_EON        0x001c
 
 
 /* AMD */
@@ -166,6 +167,8 @@
 /* Winbond */
 #define W49V002A	0x00b0
 
+/* EON */
+#define EON29LV400BB    0x22BA
 
 /*
  * Unlock address sets for AMD command sets.
@@ -1710,6 +1713,23 @@
 			ERASEINFO(0x02000, 2),
 			ERASEINFO(0x04000, 1),
 		}
+        },{
+                .mfr_id         = MANUFACTURER_EON,     /* TomTom GO */
+                .dev_id         = EON29LV400BB,
+                .name           = "EON AM29LV400BB",
+                .uaddr          = {
+                        [1] = MTD_UADDR_0x0AAA_0x0555,  /* x16 */
+                        [0] = MTD_UADDR_0x0555_0x02AA,  /* x8 */
+                },
+                .DevSize        = SIZE_512KiB,
+                .CmdSet         = P_ID_AMD_STD,
+                .NumEraseRegions= 4,
+                .regions        = {
+                        ERASEINFO(0x04000,1),
+                        ERASEINFO(0x02000,2),
+                        ERASEINFO(0x08000,1),
+                        ERASEINFO(0x10000,7),
+                }
 	}
 };
 
@@ -1729,6 +1749,14 @@
 	u32 ofs = cfi_build_cmd_addr(0, cfi_interleave(cfi), cfi->device_type);
 	mask = (1 << (cfi->device_type * 8)) -1;
 	result = map_read(map, base + ofs);
+#ifdef CONFIG_MTD_EON
+        if( (result.x[0] & mask) == 0x7f ) {
+         ofs = cfi_build_cmd_addr(0x100, cfi_interleave(cfi), cfi->device_type);
+         mask = (1 << (cfi->device_type * 8)) -1;
+         result = map_read(map, base + ofs);
+        }       
+#endif          
+
 	return result.x[0] & mask;
 }
 
diff -Naur mtd-orig/drivers/mtd/chips/Kconfig mtd/drivers/mtd/chips/Kconfig
--- mtd-orig/drivers/mtd/chips/Kconfig	2005-06-07 01:04:35.000000000 +0200
+++ mtd/drivers/mtd/chips/Kconfig	2005-07-05 15:38:25.000000000 +0200
@@ -221,6 +221,16 @@
 	  be set to at least 1.  This can also be adjusted at driver load
 	  time with the retry_cmd_max module parameter.
 
+config MTD_EON
+        depends on MTD_CFI_AMDSTD
+        bool "Work-arounds for broken EON chips"
+        help
+          This option enables workarounds for the broken chips produced
+          by EON. Chips for which this workaround is necessary include
+          EN29LV400AB/T and EN29LV800BB/T. If you have such a chip, and
+          are experiencing problems (eg. incorrect CFI detection), say
+          'Y' here. Otherwise you should probably say 'N' here.
+
 config MTD_CFI_STAA
 	tristate "Support for ST (Advanced Architecture) flash chips"
 	depends on MTD_GEN_PROBE