fix printing ENH_START_ADDR

The enhanced user area start field is 4 bytes long
according to the eMMC 4.41 spec.
Signed-off-by: Ben Gardiner <bengardiner@nanometrics.ca>
Signed-off-by: Chris Ball <cjb@laptop.org>

mmc.h

@@ -47,6 +47,10 @@
 #define EXT_CSD_RST_N_FUNCTION		162	/* R/W */
 #define EXT_CSD_PARTITIONING_SUPPORT	160	/* RO */
 #define EXT_CSD_PARTITION_SETTING_COMPLETED	155	/* R/W */
+#define EXT_CSD_ENH_START_ADDR_3	139
+#define EXT_CSD_ENH_START_ADDR_2	138
+#define EXT_CSD_ENH_START_ADDR_1	137
+#define EXT_CSD_ENH_START_ADDR_0	136
 #define EXT_CSD_NATIVE_SECTOR_SIZE	63 /* R */
 #define EXT_CSD_USE_NATIVE_SECTOR	62 /* R/W */
 #define EXT_CSD_DATA_SECTOR_SIZE	61 /* R */

mmc_cmds.c

@@ -746,9 +746,13 @@ int do_read_extcsd(int nargs, char **argv)
 		printf("Enhanced User Data Area Size"
 			" [ENH_SIZE_MULT]: 0x%06x\n", (ext_csd[142] << 16) |
 			(ext_csd[141] << 8) | ext_csd[140]);
+
+		reg =	(ext_csd[EXT_CSD_ENH_START_ADDR_3] << 24) |
+			(ext_csd[EXT_CSD_ENH_START_ADDR_2] << 16) |
+			(ext_csd[EXT_CSD_ENH_START_ADDR_1] << 8) |
+			ext_csd[EXT_CSD_ENH_START_ADDR_0];
 		printf("Enhanced User Data Start Address"
-			" [ENH_START_ADDR]: 0x%06x\n", (ext_csd[139] << 16) |
-			   (ext_csd[138] << 8) | ext_csd[137]);
+			" [ENH_START_ADDR]: 0x%06x\n", reg);
 
 		/* A441]: reserved [135] */
 		printf("Bad Block Management mode"