[U-Boot] [PATCH] fdt: support booting with dtb in Android image

[Shawn Guo]

Some platforms choose to store device tree blob in Android image second
area.  Let's try to look for dtb from there when booting an Android
image, and use it for booting if found.

Signed-off-by: Shawn Guo <shawn.guo at linaro.org>
---
 common/image-fdt.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/common/image-fdt.c b/common/image-fdt.c
index 95748f0ae108..57f150311392 100644
--- a/common/image-fdt.c
+++ b/common/image-fdt.c
@@ -230,6 +230,7 @@ int boot_get_fdt(int flag, int argc, char * const argv[], uint8_t arch,
 	ulong		load, load_end;
 	ulong		image_start, image_data, image_end;
 #endif
+	ulong		img_addr;
 	ulong		fdt_addr;
 	char		*fdt_blob = NULL;
 	void		*buf;
@@ -245,6 +246,9 @@ int boot_get_fdt(int flag, int argc, char * const argv[], uint8_t arch,
 	*of_flat_tree = NULL;
 	*of_size = 0;
 
+	img_addr = simple_strtoul(argv[0], NULL, 16);
+	buf = map_sysmem(img_addr, 0);
+
 	if (argc > 2)
 		select = argv[2];
 	if (select || genimg_has_config(images)) {
@@ -415,6 +419,23 @@ int boot_get_fdt(int flag, int argc, char * const argv[], uint8_t arch,
 			debug("## No Flattened Device Tree\n");
 			goto no_fdt;
 		}
+#ifdef CONFIG_ANDROID_BOOT_IMAGE
+	} else if (genimg_get_format(buf) == IMAGE_FORMAT_ANDROID) {
+		struct andr_img_hdr *hdr = buf;
+		ulong fdt_data, fdt_len;
+
+		if (android_image_get_second(hdr, &fdt_data, &fdt_len) != 0)
+			goto no_fdt;
+
+		fdt_blob = (char *)fdt_data;
+		if (fdt_check_header(fdt_blob) != 0)
+			goto no_fdt;
+
+		if (fdt_totalsize(fdt_blob) != fdt_len)
+			goto error;
+
+		debug("## Using FDT found in Android image second area\n");
+#endif
 	} else {
 		debug("## No Flattened Device Tree\n");
 		goto no_fdt;
-- 
2.18.0