[PATCH] boot: android: Fix ramdisk loading for v2 header

[Mattijs Korpershoek]

Before
commit da3447d09fa0 ("android: Fix ramdisk loading for bootimage v3+"),
the ramdisk was loaded from img_data.ramdisk_ptr, ignoring offset
provided via mkbootimg.

commit da3447d09fa0 ("android: Fix ramdisk loading for bootimage v3+")
rightfully fixes this by switching to use img_data.ramdisk_addr instead.

However, it does not copy the ramdisk content to img_data.ramdisk_addr
in case we use boot image v2.

Because of this, we can no longer boot Android on Khadas vim3 board:

[    3.940361] RAMDISK: Couldn't find valid RAM disk image starting at 0.

Add the missing memcpy() to fix the issue.

Fixes: da3447d09fa0 ("android: Fix ramdisk loading for bootimage v3+")
Signed-off-by: Mattijs Korpershoek <mkorpershoek at baylibre.com>
---
Note that on default AOSP boot images, there is another bug: the
ramdisk offset is wronly configured:

$ file boot.img
boot.img: Android bootimg, kernel (0x11080000), ramdisk (0x11000000),
page size: 2048

With this, we have a maximum ramdisk size of 0x80000 bytes (512KiB)
which is not enough. The kernel would overlap on the ramdisk address.

This can be fixed by repacking the boot image:
$ unpack_bootimg --boot_img boot.img --out out --format=mkbootimg | \
  tee mkbootimg_args

$ vim mkbootimg_args # change --ramdisk_offset to 0x20000000

$ sh -c "mkbootimg $(cat mkbootimg_args) -o boot_repacked.img"
---
 boot/image-android.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/boot/image-android.c b/boot/image-android.c
index 774565fd1fea..8934491c35f2 100644
--- a/boot/image-android.c
+++ b/boot/image-android.c
@@ -409,6 +409,10 @@ int android_image_get_ramdisk(const void *hdr, const void *vendor_boot_img,
 			       (ramdisk_ptr), (void *)img_data.bootconfig_addr,
 			       img_data.bootconfig_size);
 		}
+	} else {
+		ramdisk_ptr = img_data.ramdisk_addr;
+		memcpy((void *)(ramdisk_ptr), (void *)img_data.ramdisk_ptr,
+		       img_data.ramdisk_size);
 	}
 
 	printf("RAM disk load addr 0x%08lx size %u KiB\n",

---
base-commit: 9cfe0cab3bf135a505e1e163ca442a4e4064d58e
change-id: 20241003-android-fix-boot-v2-ada82163bd05

Best regards,
-- 
Mattijs Korpershoek <mkorpershoek at baylibre.com>