rockchip: resrouce_img: support a/b

If apply the a/b system, open the macro CONFIG_ANDROID_AB.
Then get the dtb from the boot '_a' or '_b' image.

Change-Id: I21ad9d5a5e6e63e26bc16b1aeeb2e690c669a535
Signed-off-by: Jason Zhu <jason.zhu@rock-chips.com>

arch/arm/mach-rockchip/resource_img.c

@@ -8,6 +8,10 @@
 #include <linux/list.h>
 #include <asm/arch/resource_img.h>
 #include <boot_rkimg.h>
+#ifdef CONFIG_ANDROID_AB
+#include <android_avb/libavb_ab.h>
+#include <android_avb/rk_avb_ops_user.h>
+#endif
 #ifdef CONFIG_ANDROID_BOOT_IMAGE
 #include <android_bootloader.h>
 #include <android_image.h>
@@ -183,6 +187,15 @@ static int init_resource_list(struct resource_img_hdr *hdr)
 	if (mode == BOOT_MODE_RECOVERY)
 		boot_partname = PART_RECOVERY;
 	/* Read boot/recovery and chenc if this is an AOSP img */
+#ifdef CONFIG_ANDROID_AB
+	char slot_suffix[3] = {0};
+
+	if (rk_avb_get_current_slot(slot_suffix))
+		goto out;
+	boot_partname = android_str_append(boot_partname, slot_suffix);
+	if (boot_partname == NULL)
+		goto out;
+#endif
 	ret = part_get_info_by_name(dev_desc, boot_partname,
 					 &part_info);
 	if (ret < 0) {

common/android_bootloader.c

@@ -33,6 +33,24 @@
 #define ANDROID_ARG_FDT_FILENAME "kernel.dtb"
 #endif
 
+char *android_str_append(char *base_name, char *slot_suffix)
+{
+	char *part_name;
+	size_t part_name_len;
+
+	part_name_len = strlen(base_name) + 1;
+	if (slot_suffix)
+		part_name_len += strlen(slot_suffix);
+	part_name = malloc(part_name_len);
+	if (!part_name)
+		return NULL;
+	strcpy(part_name, base_name);
+	if (slot_suffix && (slot_suffix[0] != '\0'))
+		strcat(part_name, slot_suffix);
+
+	return part_name;
+}
+
 int android_bootloader_message_load(
 	struct blk_desc *dev_desc,
 	const disk_partition_t *part_info,

include/android_bootloader.h

@@ -77,4 +77,13 @@ int android_bootloader_boot_kernel(unsigned long kernel_address);
  */
 int android_boot_flow(unsigned long kernel_address);
 
+/** str_append- add str to tail.
+ *
+ * @base_name:	base name address.
+ * @slot_suffix: suffix.
+ *
+ * @return (base name + suffix)address.
+ */
+char *android_str_append(char *base_name, char *slot_suffix);
+
 #endif  /* __ANDROID_BOOTLOADER_H */