MTD/CFI: Add support for 16bit legacy AMD flash

Add entry for 512Kx16 AMD flash to jedec_table.
Read out 16bit device id if chipwidth is 16bit.
Fixed coding style after Stefans feedback

Signed-off-by: Tor Krill <tor@excito.com>

drivers/mtd/cfi_flash.c

@@ -364,6 +364,20 @@ static inline uchar flash_read_uchar (flash_info_t * info, uint offset)
 	return retval;
 }
 
+/*-----------------------------------------------------------------------
+ * read a word at a port width address, assume 16bit bus
+ */
+static inline ushort flash_read_word (flash_info_t * info, uint offset)
+{
+	ushort *addr, retval;
+
+	addr = flash_map (info, 0, offset);
+	retval = flash_read16 (addr);
+	flash_unmap (info, 0, offset, addr);
+	return retval;
+}
+
+
 /*-----------------------------------------------------------------------
  * read a long word by picking the least significant byte of each maximum
  * port size word. Swap for ppc format.
@@ -1449,17 +1463,29 @@ static void cmdset_amd_read_jedec_ids(flash_info_t *info)
 	flash_unlock_seq(info, 0);
 	flash_write_cmd(info, 0, info->addr_unlock1, FLASH_CMD_READ_ID);
 	udelay(1000); /* some flash are slow to respond */
+
 	info->manufacturer_id = flash_read_uchar (info,
 					FLASH_OFFSET_MANUFACTURER_ID);
-	info->device_id = flash_read_uchar (info,
-					FLASH_OFFSET_DEVICE_ID);
-	if (info->device_id == 0x7E) {
-		/* AMD 3-byte (expanded) device ids */
-		info->device_id2 = flash_read_uchar (info,
-					FLASH_OFFSET_DEVICE_ID2);
-		info->device_id2 <<= 8;
-		info->device_id2 |= flash_read_uchar (info,
-					FLASH_OFFSET_DEVICE_ID3);
+
+	switch (info->chipwidth){
+	case FLASH_CFI_8BIT:
+		info->device_id = flash_read_uchar (info,
+						FLASH_OFFSET_DEVICE_ID);
+		if (info->device_id == 0x7E) {
+			/* AMD 3-byte (expanded) device ids */
+			info->device_id2 = flash_read_uchar (info,
+						FLASH_OFFSET_DEVICE_ID2);
+			info->device_id2 <<= 8;
+			info->device_id2 |= flash_read_uchar (info,
+						FLASH_OFFSET_DEVICE_ID3);
+		}
+		break;
+	case FLASH_CFI_16BIT:
+		info->device_id = flash_read_word (info,
+						FLASH_OFFSET_DEVICE_ID);
+		break;
+	default:
+		break;
 	}
 	flash_write_cmd(info, 0, 0, AMD_CMD_RESET);
 }

drivers/mtd/jedec_flash.c

@@ -216,6 +216,25 @@ static const struct amd_flash_info jedec_table[] = {
 		}
 	},
 #endif
+#ifdef CFG_FLASH_LEGACY_512Kx16
+	{
+		.mfr_id		= MANUFACTURER_AMD,
+		.dev_id		= AM29LV400BB,
+		.name		= "AMD AM29LV400BB",
+		.uaddr		= {
+			[1] = MTD_UADDR_0x0555_0x02AA /* x16 */
+		},
+		.DevSize	= SIZE_512KiB,
+		.CmdSet		= CFI_CMDSET_AMD_LEGACY,
+		.NumEraseRegions= 4,
+		.regions	= {
+			ERASEINFO(0x04000,1),
+			ERASEINFO(0x02000,2),
+			ERASEINFO(0x08000,1),
+			ERASEINFO(0x10000,7),
+		}
+	},
+#endif
 };
 
 static inline void fill_info(flash_info_t *info, const struct amd_flash_info *jedec_entry, ulong base)