fdt: boot_get_fdt: android: use ENV 'fdtaddr' as fallback
Our platform doesn't store the DTB into the Android image second area,
but rather copies the DTB to RAM from a dedicated dtb.img partition [0],
prior to booting the Android image by calling bootm.
Similar to [1], we find it useful to just call 'bootm' and have the
right DTB being passed to OS (assuming its address has been previously
stored in 'fdtaddr' by calling `fdt addr <dtb-addr>`).
Booting Android with DTB from 'fdtaddr' will only occur if:
- No DTB is embedded in the second area of Android image
- 'fdtaddr' points to a valid DTB in RAM
[0] https://source.android.com/devices/architecture/dto/partitions
[1] https://patchwork.ozlabs.org/patch/1046652/
("Support boot Android image without address on bootm command")
Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/common/image-fdt.c b/common/image-fdt.c
index a5d8b41..3aa5fff 100644
--- a/common/image-fdt.c
+++ b/common/image-fdt.c
@@ -469,7 +469,15 @@
debug("## Using FDT in Android image second area\n");
} else {
- goto no_fdt;
+ fdt_addr = env_get_hex("fdtaddr", 0);
+ if (!fdt_addr)
+ goto no_fdt;
+
+ fdt_blob = map_sysmem(fdt_addr, 0);
+ if (fdt_check_header(fdt_blob))
+ goto no_fdt;
+
+ debug("## Using FDT at ${fdtaddr}=Ox%lx\n", fdt_addr);
}
#endif
} else {