[U-Boot] [PATCH 1/2] [rfc] parse the second area of android image

[Bin Chen]

The second area of android image was intended to put a 2nd stage
bootloader but in practice were rarely used (in my knowledge).

An proposal was made to the AOSP to (re)use the second area as the dtb[1],
This patch itself doesn't depend on that proposal being accepted but it won't
be that helpful as well if that proposal won't be accepted. But don't do
any harm as well.

[1] https://android-review.googlesource.com/#/c/417447/
Signed-off-by: Bin Chen <bin.chen at linaro.org>
---
 common/image-android.c | 19 +++++++++++++++++++
 include/image.h        |  2 ++
 2 files changed, 21 insertions(+)

diff --git a/common/image-android.c b/common/image-android.c
index ee03b96..7daa5fa 100644
--- a/common/image-android.c
+++ b/common/image-android.c
@@ -146,6 +146,25 @@ int android_image_get_ramdisk(const struct andr_img_hdr *hdr,
 	return 0;
 }
 
+int android_image_get_second(const struct andr_img_hdr *hdr,
+			      ulong *second_data, ulong *second_len)
+{
+	if (!hdr->second_size) {
+		*second_data = *second_len = 0;
+		return -1;
+	}
+
+	*second_data = (unsigned long)hdr;
+	*second_data += hdr->page_size;
+	*second_data += ALIGN(hdr->kernel_size, hdr->page_size);
+	*second_data += ALIGN(hdr->ramdisk_size, hdr->page_size);
+
+	printf("second address is 0x%lx\n",*second_data);
+
+	*second_len = hdr->second_size;
+	return 0;
+}
+
 #if !defined(CONFIG_SPL_BUILD)
 /**
  * android_print_contents - prints out the contents of the Android format image
diff --git a/include/image.h b/include/image.h
index 3f26f9b..8264c52 100644
--- a/include/image.h
+++ b/include/image.h
@@ -1237,6 +1237,8 @@ int android_image_get_kernel(const struct andr_img_hdr *hdr, int verify,
 			     ulong *os_data, ulong *os_len);
 int android_image_get_ramdisk(const struct andr_img_hdr *hdr,
 			      ulong *rd_data, ulong *rd_len);
+int android_image_get_second(const struct andr_img_hdr *hdr,
+			      ulong *second_data, ulong *second_len);
 ulong android_image_get_end(const struct andr_img_hdr *hdr);
 ulong android_image_get_kload(const struct andr_img_hdr *hdr);
 void android_print_contents(const struct andr_img_hdr *hdr);
-- 
1.9.1