bootstd: android: add non-A/B image support

Update android bootmeth to support non-A/B image.
Enable AB support only when ANDROID_AB is enabled.

Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Signed-off-by: Guillaume La Roque <glaroque@baylibre.com>
Link: https://lore.kernel.org/r/20241126-adnroidv2-v4-2-11636106dc69@baylibre.com
Signed-off-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>

boot/Kconfig

@@ -500,7 +500,6 @@ config BOOTMETH_ANDROID
 	bool "Bootdev support for Android"
 	depends on X86 || ARM || SANDBOX
 	depends on CMDLINE
-	select ANDROID_AB
 	select ANDROID_BOOT_IMAGE
 	select CMD_BCB
 	imply CMD_FASTBOOT

boot/bootmeth_android.c

@@ -29,6 +29,7 @@
 #define BCB_PART_NAME "misc"
 #define BOOT_PART_NAME "boot"
 #define VENDOR_BOOT_PART_NAME "vendor_boot"
+#define SLOT_LEN 2
 
 /**
  * struct android_priv - Private data
@@ -42,7 +43,7 @@
  */
 struct android_priv {
 	enum android_boot_mode boot_mode;
-	char slot[2];
+	char *slot;
 	u32 header_version;
 };
 
@@ -71,7 +72,11 @@ static int scan_boot_part(struct udevice *blk, struct android_priv *priv)
 	char *buf;
 	int ret;
 
-	sprintf(partname, BOOT_PART_NAME "_%s", priv->slot);
+	if (priv->slot)
+		sprintf(partname, BOOT_PART_NAME "_%s", priv->slot);
+	else
+		sprintf(partname, BOOT_PART_NAME);
+
 	ret = part_get_info_by_name(desc, partname, &partition);
 	if (ret < 0)
 		return log_msg_ret("part info", ret);
@@ -108,7 +113,11 @@ static int scan_vendor_boot_part(struct udevice *blk, struct android_priv *priv)
 	char *buf;
 	int ret;
 
-	sprintf(partname, VENDOR_BOOT_PART_NAME "_%s", priv->slot);
+	if (priv->slot)
+		sprintf(partname, VENDOR_BOOT_PART_NAME "_%s", priv->slot);
+	else
+		sprintf(partname, VENDOR_BOOT_PART_NAME);
+
 	ret = part_get_info_by_name(desc, partname, &partition);
 	if (ret < 0)
 		return log_msg_ret("part info", ret);
@@ -142,6 +151,11 @@ static int android_read_slot_from_bcb(struct bootflow *bflow, bool decrement)
 	char slot_suffix[3];
 	int ret;
 
+	if (!CONFIG_IS_ENABLED(ANDROID_AB)) {
+		priv->slot = NULL;
+		return 0;
+	}
+
 	ret = part_get_info_by_name(desc, BCB_PART_NAME, &misc);
 	if (ret < 0)
 		return log_msg_ret("part", ret);
@@ -150,6 +164,7 @@ static int android_read_slot_from_bcb(struct bootflow *bflow, bool decrement)
 	if (ret < 0)
 		return log_msg_ret("slot", ret);
 
+	priv->slot = malloc(SLOT_LEN);
 	priv->slot[0] = BOOT_SLOT_NAME(ret);
 	priv->slot[1] = '\0';
 
@@ -274,7 +289,7 @@ static int android_read_bootflow(struct udevice *dev, struct bootflow *bflow)
 	configure_serialno(bflow);
 	configure_bootloader_version(bflow);
 
-	if (priv->boot_mode == ANDROID_BOOT_MODE_NORMAL) {
+	if (priv->boot_mode == ANDROID_BOOT_MODE_NORMAL && priv->slot) {
 		ret = bootflow_cmdline_set_arg(bflow, "androidboot.force_normal_boot",
 					       "1", false);
 		if (ret < 0) {
@@ -323,14 +338,28 @@ static int read_slotted_partition(struct blk_desc *desc, const char *const name,
 {
 	struct disk_partition partition;
 	char partname[PART_NAME_LEN];
+	size_t partname_len;
 	int ret;
 	u32 n;
 
-	/* Ensure name fits in partname it should be: <name>_<slot>\0 */
+	/*
-	if (strlen(name) > (PART_NAME_LEN - 2 - 1))
+	 * Ensure name fits in partname.
+	 * For A/B, it should be <name>_<slot>\0
+	 * For non A/B, it should be <name>\0
+	 */
+	if (CONFIG_IS_ENABLED(ANDROID_AB))
+		partname_len = PART_NAME_LEN - 2 - 1;
+	else
+		partname_len = PART_NAME_LEN - 1;
+
+	if (strlen(name) > partname_len)
 		return log_msg_ret("name too long", -EINVAL);
 
-	sprintf(partname, "%s_%s", name, slot);
+	if (slot)
+		sprintf(partname, "%s_%s", name, slot);
+	else
+		sprintf(partname, "%s", name);
+
 	ret = part_get_info_by_name(desc, partname, &partition);
 	if (ret < 0)
 		return log_msg_ret("part", ret);
@@ -382,7 +411,7 @@ static int run_avb_verification(struct bootflow *bflow)
 	AvbSlotVerifyData *out_data;
 	enum avb_boot_state boot_state;
 	char *extra_args;
-	char slot_suffix[3];
+	char slot_suffix[3] = "";
 	bool unlocked = false;
 	int ret;
 
@@ -390,7 +419,8 @@ static int run_avb_verification(struct bootflow *bflow)
 	if (!avb_ops)
 		return log_msg_ret("avb ops", -ENOMEM);
 
-	sprintf(slot_suffix, "_%s", priv->slot);
+	if (priv->slot)
+		sprintf(slot_suffix, "_%s", priv->slot);
 
 	ret = avb_ops->read_is_device_unlocked(avb_ops, &unlocked);
 	if (ret != AVB_IO_RESULT_OK)
@@ -480,6 +510,9 @@ static int boot_android_normal(struct bootflow *bflow)
 	}
 	set_abootimg_addr(loadaddr);
 
+	if (priv->slot)
+		free(priv->slot);
+
 	ret = bootm_boot_start(loadaddr, bflow->cmdline);
 
 	return log_msg_ret("boot", ret);

configs/am62x_a53_android.config

@@ -11,6 +11,7 @@ CONFIG_RANDOM_UUID=y # Needed for FASTBOOT_CMD_OEM_FORMAT
 CONFIG_FASTBOOT_CMD_OEM_FORMAT=y
 # Enable Android boot flow
 CONFIG_BOOTMETH_ANDROID=y
+CONFIG_ANDROID_AB=y
 CONFIG_SYS_BOOTM_LEN=0x4000000
 CONFIG_SYS_MALLOC_LEN=0x08000000
 CONFIG_AVB_VERIFY=y

configs/sandbox_defconfig

@@ -50,6 +50,7 @@ CONFIG_LOG_DEFAULT_LEVEL=6
 CONFIG_LOGF_FUNC=y
 CONFIG_DISPLAY_BOARDINFO_LATE=y
 CONFIG_STACKPROTECTOR=y
+CONFIG_ANDROID_AB=y
 CONFIG_CMD_CPU=y
 CONFIG_CMD_LICENSE=y
 CONFIG_CMD_SMBIOS=y