[PATCH v1 1/2] boot: android: Add Android 13+ bootflow support to bootmeth.

[Valentin Liu <valentinliu@icloud.com>]

The devices launching Android 13+ were using a new partition
named init_boot to store generic ramdisk.

In the new bootflow, kernel still be stored in boot image,
however, the First Stage files in ramdisk were moved to
init_boot image. We should load it to memory and verify it
so that the kernel can execute init program to continue booting.

Currently, we have supported loading the init_boot image by
abootimg command, but we still need bring this ability to
bootmeth, so that booting Android 13+ will be more easily.
Bootmeth will be able to recognize the new partition layout,
and boot Android normally.

Link: https://source.android.com/docs/core/architecture/partitions/generic-boot
Signed-off-by: Valentin Liu <valentinliu@icloud.com>
---
 boot/bootmeth_android.c          | 67 ++++++++++++++++++++++++++++++++
 boot/image-android.c             | 16 ++++++++
 cmd/abootimg.c                   |  5 +++
 doc/develop/bootstd/overview.rst |  3 ++
 include/android_image.h          |  1 +
 include/image.h                  | 35 +++++++++++++++++
 6 files changed, 127 insertions(+)

diff --git a/boot/bootmeth_android.c b/boot/bootmeth_android.c
index ec255b072af..904640d360b 100644
--- a/boot/bootmeth_android.c
+++ b/boot/bootmeth_android.c
@@ -29,6 +29,7 @@
 #define BCB_FIELD_COMMAND_SZ 32
 #define BCB_PART_NAME "misc"
 #define BOOT_PART_NAME "boot"
+#define INIT_BOOT_PART_NAME "init_boot"
 #define VENDOR_BOOT_PART_NAME "vendor_boot"
 #define SLOT_LEN 2
 
@@ -47,6 +48,7 @@ struct android_priv {
 	char *slot;
 	u32 header_version;
 	u32 boot_img_size;
+	u32 init_boot_img_size;
 	u32 vendor_boot_img_size;
 };
 
@@ -113,6 +115,51 @@ static int scan_boot_part(struct udevice *blk, struct android_priv *priv)
 	return 0;
 }
 
+static int scan_init_boot_part(struct udevice *blk, struct android_priv *priv)
+{
+	struct blk_desc *desc = dev_get_uclass_plat(blk);
+	struct disk_partition partition;
+	char partname[PART_NAME_LEN];
+	ulong num_blks, bufsz;
+	char *buf;
+	int ret;
+
+	if (priv->slot)
+		sprintf(partname, INIT_BOOT_PART_NAME "_%s", priv->slot);
+	else
+		sprintf(partname, INIT_BOOT_PART_NAME);
+
+	ret = part_get_info_by_name(desc, partname, &partition);
+	if (ret < 0)
+		return log_msg_ret("part info", ret);
+
+	num_blks = DIV_ROUND_UP(sizeof(struct andr_boot_img_hdr_v3), desc->blksz);
+	bufsz = num_blks * desc->blksz;
+	buf = malloc(bufsz);
+	if (!buf)
+		return log_msg_ret("buf", -ENOMEM);
+
+	ret = blk_read(blk, partition.start, num_blks, buf);
+	if (ret != num_blks) {
+		free(buf);
+		return log_msg_ret("part read", -EIO);
+	}
+
+	if (!is_android_boot_image_header(buf)) {
+		free(buf);
+		return log_msg_ret("header", -ENOENT);
+	}
+
+	if (!android_image_get_bootimg_size(buf, &priv->init_boot_img_size)) {
+		free(buf);
+		return log_msg_ret("get init bootimg size", -EINVAL);
+	}
+
+	free(buf);
+
+	return 0;
+}
+
 static int scan_vendor_boot_part(struct udevice *blk, struct android_priv *priv)
 {
 	struct blk_desc *desc = dev_get_uclass_plat(blk);
@@ -291,6 +338,17 @@ static int android_read_bootflow(struct udevice *dev, struct bootflow *bflow)
 		goto free_priv;
 	}
 
+	if (priv->header_version >= 4) {
+		ret = scan_init_boot_part(bflow->blk, priv);
+		if (ret < 0) {
+			/*
+			 * Android 12 devices do not have the init_boot partition.
+			 * Some devices upgraded to Android 13 or later from
+			 * earlier Android versions may also not have one.
+			 */
+			log_debug("scan init_boot failed: err=%d\n", ret);
+		}
+	}
 	if (priv->header_version >= 3) {
 		ret = scan_vendor_boot_part(bflow->blk, priv);
 		if (ret < 0) {
@@ -556,6 +614,7 @@ static int boot_android_normal(struct bootflow *bflow)
 	struct android_priv *priv = bflow->bootmeth_priv;
 	int ret;
 	ulong loadaddr = env_get_hex("loadaddr", 0);
+	ulong iloadaddr = env_get_hex("init_boot_comp_addr_r", 0);
 	ulong vloadaddr = env_get_hex("vendor_boot_comp_addr_r", 0);
 
 	ret = run_avb_verification(bflow);
@@ -572,6 +631,14 @@ static int boot_android_normal(struct bootflow *bflow)
 	if (ret < 0)
 		return log_msg_ret("read boot", ret);
 
+	if (priv->header_version >= 4 && priv->init_boot_img_size > 0) {
+		ret = read_slotted_partition(desc, "init_boot", priv->slot,
+					     priv->init_boot_img_size,
+					     iloadaddr);
+		if (ret < 0)
+			return log_msg_ret("read init_boot", ret);
+		set_ainit_bootimg_addr(iloadaddr);
+	}
 	if (priv->header_version >= 3) {
 		ret = read_slotted_partition(desc, "vendor_boot", priv->slot,
 					     priv->vendor_boot_img_size, vloadaddr);
diff --git a/boot/image-android.c b/boot/image-android.c
index 7740cae8cb6..3f5634b469f 100644
--- a/boot/image-android.c
+++ b/boot/image-android.c
@@ -326,6 +326,22 @@ bool android_image_get_data(const void *boot_hdr, const void *vendor_boot_hdr,
 	return true;
 }
 
+bool android_image_get_data_v4(const void *boot_hdr, const void *vendor_boot_hdr,
+			       const void *init_boot_hdr, struct andr_image_data *data)
+{
+	if (!android_image_get_data(boot_hdr, vendor_boot_hdr, data))
+		return false;
+
+	if (!is_android_boot_image_header(init_boot_hdr)) {
+		printf("Incorrect init boot image header\n");
+		return false;
+	}
+
+	android_boot_image_v3_v4_parse_hdr(init_boot_hdr, data);
+
+	return true;
+}
+
 static ulong android_image_get_kernel_addr(struct andr_image_data *img_data,
 					   ulong comp)
 {
diff --git a/cmd/abootimg.c b/cmd/abootimg.c
index eae3e643b60..e8e6b8f5ced 100644
--- a/cmd/abootimg.c
+++ b/cmd/abootimg.c
@@ -33,6 +33,11 @@ ulong get_ainit_bootimg_addr(void)
 	return _ainit_bootimg_addr;
 }
 
+void set_ainit_bootimg_addr(ulong addr)
+{
+	_ainit_bootimg_addr = addr;
+}
+
 ulong get_avendor_bootimg_addr(void)
 {
 	return _avendor_bootimg_addr;
diff --git a/doc/develop/bootstd/overview.rst b/doc/develop/bootstd/overview.rst
index ec9fafa0fa0..f1306ae0a8f 100644
--- a/doc/develop/bootstd/overview.rst
+++ b/doc/develop/bootstd/overview.rst
@@ -293,6 +293,9 @@ script_offset_f
 script_size_f
     Size of the script to load, e.g. 0x2000
 
+init_boot_comp_addr_r
+    Address to which to load the init_boot Android image, e.g. 0xd0000000
+
 vendor_boot_comp_addr_r
     Address to which to load the vendor_boot Android image, e.g. 0xe0000000
 
diff --git a/include/android_image.h b/include/android_image.h
index a2d80499ba3..134b5ed74d6 100644
--- a/include/android_image.h
+++ b/include/android_image.h
@@ -357,6 +357,7 @@ struct andr_image_data {
 	ulong tags_addr;  /* physical addr for kernel tags */
 	u32 header_version;  /* version of the boot image header */
 	u32 boot_img_total_size;  /* boot image size */
+	u32 init_boot_img_total_size;  /* init boot image size */
 	u32 vendor_boot_img_total_size;  /* vendor boot image size */
 };
 
diff --git a/include/image.h b/include/image.h
index 6edcb1995bf..1c725fc2601 100644
--- a/include/image.h
+++ b/include/image.h
@@ -2041,6 +2041,23 @@ bool android_image_get_vendor_bootimg_size(const void *hdr, u32 *vendor_boot_img
 bool android_image_get_data(const void *boot_hdr, const void *vendor_boot_hdr,
 			    struct andr_image_data *data);
 
+/**
+ * android_image_get_data_v4() - Parse Android header version 4 boot images
+ *
+ * This is used to parse boot, vendor-boot and init boot header into
+ * andr_image_data generic structure.
+ * The Android 13 and newer has splited parameters from boot and
+ * vendor_boot images to the init_boot image.
+ *
+ * @boot_hdr: Pointer to boot image header
+ * @vendor_boot_hdr: Pointer to vendor boot image header
+ * @init_boot_hdr: Pointer to init boot image header
+ * @data: Pointer to generic boot format structure
+ * Return: true if succeeded, false otherwise
+ */
+bool android_image_get_data_v4(const void *boot_hdr, const void *vendor_boot_hdr,
+			       const void *init_boot_hdr, struct andr_image_data *data);
+
 struct andr_boot_img_hdr_v0;
 
 /**
@@ -2167,6 +2184,17 @@ bool android_image_print_dtb_contents(ulong hdr_addr);
  */
 bool is_android_boot_image_header(const void *hdr);
 
+/**
+ * is_android_init_boot_image_header() - Check the magic of init boot image
+ *
+ * This checks the header of Android init boot image and verifies the
+ * magic is "ANDROID!" (same with the boot image)
+ *
+ * @init_boot_img: Pointer to boot image
+ * Return: non-zero if the magic is correct, zero otherwise
+ */
+bool is_android_init_boot_image_header(const void *init_boot_img);
+
 /**
  * is_android_vendor_boot_image_header() - Check the magic of vendor boot image
  *
@@ -2199,6 +2227,13 @@ void set_abootimg_addr(ulong addr);
  */
 ulong get_ainit_bootimg_addr(void);
 
+/**
+ * set_ainit_bootimg_addr() - Set Android init boot image address
+ *
+ * Return: no returned results
+ */
+void set_ainit_bootimg_addr(ulong addr);
+
 /**
  * get_avendor_bootimg_addr() - Get Android vendor boot image address
  *
-- 
2.53.0