mmc-utils: add check for max enhanced user area

In addition to user area, General purpose partition can be
be marked with enhanced attribute, retain enhanced attributes of
gp partition while creating enhanced user area and add
check for max enhanced area of the device.

Signed-off-by: Balaji T K <balajitk@ti.com>
Signed-off-by: Chris Ball <chris@printf.net>
diff --git a/mmc_cmds.c b/mmc_cmds.c
index cea943f..2fc8d4a 100644
--- a/mmc_cmds.c
+++ b/mmc_cmds.c
@@ -498,6 +498,89 @@
 	return 0;
 }
 
+int check_enhanced_area_total_limit(const char * const device, int fd)
+{
+	__u8 ext_csd[512];
+	__u32 regl;
+	unsigned long max_enh_area_sz, user_area_sz, enh_area_sz = 0;
+	unsigned long gp4_part_sz, gp3_part_sz, gp2_part_sz, gp1_part_sz;
+	unsigned int wp_sz, erase_sz;
+	int ret;
+
+	ret = read_extcsd(fd, ext_csd);
+	if (ret) {
+		fprintf(stderr, "Could not read EXT_CSD from %s\n", device);
+		exit(1);
+	}
+	wp_sz = get_hc_wp_grp_size(ext_csd);
+	erase_sz = get_hc_erase_grp_size(ext_csd);
+
+	regl = (ext_csd[EXT_CSD_GP_SIZE_MULT_4_2] << 16) |
+		(ext_csd[EXT_CSD_GP_SIZE_MULT_4_1] << 8) |
+		ext_csd[EXT_CSD_GP_SIZE_MULT_4_0];
+	gp4_part_sz = 512l * regl * erase_sz * wp_sz;
+	if (ext_csd[EXT_CSD_PARTITIONS_ATTRIBUTE] & EXT_CSD_ENH_4) {
+		enh_area_sz += gp4_part_sz;
+		printf("Enhanced GP4 Partition Size [GP_SIZE_MULT_4]: 0x%06x\n", regl);
+		printf(" i.e. %lu KiB\n", gp4_part_sz);
+	}
+
+	regl = (ext_csd[EXT_CSD_GP_SIZE_MULT_3_2] << 16) |
+		(ext_csd[EXT_CSD_GP_SIZE_MULT_3_1] << 8) |
+		ext_csd[EXT_CSD_GP_SIZE_MULT_3_0];
+	gp3_part_sz = 512l * regl * erase_sz * wp_sz;
+	if (ext_csd[EXT_CSD_PARTITIONS_ATTRIBUTE] & EXT_CSD_ENH_3) {
+		enh_area_sz += gp3_part_sz;
+		printf("Enhanced GP3 Partition Size [GP_SIZE_MULT_3]: 0x%06x\n", regl);
+		printf(" i.e. %lu KiB\n", gp3_part_sz);
+	}
+
+	regl = (ext_csd[EXT_CSD_GP_SIZE_MULT_2_2] << 16) |
+		(ext_csd[EXT_CSD_GP_SIZE_MULT_2_1] << 8) |
+		ext_csd[EXT_CSD_GP_SIZE_MULT_2_0];
+	gp2_part_sz = 512l * regl * erase_sz * wp_sz;
+	if (ext_csd[EXT_CSD_PARTITIONS_ATTRIBUTE] & EXT_CSD_ENH_2) {
+		enh_area_sz += gp2_part_sz;
+		printf("Enhanced GP2 Partition Size [GP_SIZE_MULT_2]: 0x%06x\n", regl);
+		printf(" i.e. %lu KiB\n", gp2_part_sz);
+	}
+
+	regl = (ext_csd[EXT_CSD_GP_SIZE_MULT_1_2] << 16) |
+		(ext_csd[EXT_CSD_GP_SIZE_MULT_1_1] << 8) |
+		ext_csd[EXT_CSD_GP_SIZE_MULT_1_0];
+	gp1_part_sz = 512l * regl * erase_sz * wp_sz;
+	if (ext_csd[EXT_CSD_PARTITIONS_ATTRIBUTE] & EXT_CSD_ENH_1) {
+		enh_area_sz += gp1_part_sz;
+		printf("Enhanced GP1 Partition Size [GP_SIZE_MULT_1]: 0x%06x\n", regl);
+		printf(" i.e. %lu KiB\n", gp1_part_sz);
+	}
+
+	regl = (ext_csd[EXT_CSD_ENH_SIZE_MULT_2] << 16) |
+		(ext_csd[EXT_CSD_ENH_SIZE_MULT_1] << 8) |
+		ext_csd[EXT_CSD_ENH_SIZE_MULT_0];
+	user_area_sz = 512l * regl * erase_sz * wp_sz;
+	if (ext_csd[EXT_CSD_PARTITIONS_ATTRIBUTE] & EXT_CSD_ENH_USR) {
+		enh_area_sz += user_area_sz;
+		printf("Enhanced User Data Area Size [ENH_SIZE_MULT]: 0x%06x\n", regl);
+		printf(" i.e. %lu KiB\n", user_area_sz);
+	}
+
+	regl = (ext_csd[EXT_CSD_MAX_ENH_SIZE_MULT_2] << 16) |
+		(ext_csd[EXT_CSD_MAX_ENH_SIZE_MULT_1] << 8) |
+		ext_csd[EXT_CSD_MAX_ENH_SIZE_MULT_0];
+	max_enh_area_sz = 512l * regl * erase_sz * wp_sz;
+	printf("Max Enhanced Area Size [MAX_ENH_SIZE_MULT]: 0x%06x\n", regl);
+	printf(" i.e. %lu KiB\n", max_enh_area_sz);
+	if (enh_area_sz > max_enh_area_sz) {
+		fprintf(stderr,
+			"Programmed total enhanced size %lu KiB cannot exceed max enhanced area %lu KiB %s\n",
+			enh_area_sz, max_enh_area_sz, device);
+		return 1;
+	}
+
+	return 0;
+}
+
 int do_enh_area_set(int nargs, char **argv)
 {
 	__u8 value;
@@ -619,8 +702,8 @@
 			EXT_CSD_ENH_SIZE_MULT_0, device);
 		exit(1);
 	}
-
-	ret = write_extcsd_value(fd, EXT_CSD_PARTITIONS_ATTRIBUTE, EXT_CSD_ENH_USR);
+	value = ext_csd[EXT_CSD_PARTITIONS_ATTRIBUTE] | EXT_CSD_ENH_USR;
+	ret = write_extcsd_value(fd, EXT_CSD_PARTITIONS_ATTRIBUTE, value);
 	if (ret) {
 		fprintf(stderr, "Could not write EXT_CSD_ENH_USR to "
 			"EXT_CSD[%d] in %s\n",
@@ -628,6 +711,10 @@
 		exit(1);
 	}
 
+	ret = check_enhanced_area_total_limit(device, fd);
+	if (ret)
+		exit(1);
+
 	printf("Done setting ENH_USR area on %s\n", device);
 
 	if (!set_partitioning_setting_completed(dry_run, device, fd))