path: root/arch/arm/cpu
diff options
authorAndre Przywara <>2016-05-31 10:45:06 -0700
committerTom Rini <>2016-06-06 13:39:19 -0400
commitcdaa633fcf9c2bd54aa3c130ee727708a4e2406a (patch)
tree0dbf826c4c9895e839d107e4b9548ee0a5fd559b /arch/arm/cpu
parentbe86492bdaeb8fdfd8d66bba79a9bd899531b8b0 (diff)
arm/arm64: implement a boot header capability
Some SPL loaders (like Allwinner's boot0, and Broadcom's boot0) require a header before the actual U-Boot binary to both check its validity and to find other data to load. Sometimes this header may only be a few bytes of information, and sometimes this might simply be space that needs to be reserved for a post-processing tool. Introduce a config option to allow assembler preprocessor commands to be inserted into the code at the appropriate location; typical assembler preprocessor commands might be: .space 1000 .word 0x12345678 Signed-off-by: Andre Przywara <> Signed-off-by: Steve Rae <> Commit Notes: Please note that the current code: start.S (arm64) and vectors.S (arm) already jumps over some portion of data already, so this option basically just increases the size of this region (and the resulting binary). For use with Allwinner's boot0 blob there is a tool called boot0img[1], which fills the header to allow booting A64 based boards. For the Pine64 we need a 1536 byte header (including the branch instruction) at the moment, so we add this to the defconfig. [1] END Reviewed-by: Tom Rini <>
Diffstat (limited to 'arch/arm/cpu')
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv8/start.S b/arch/arm/cpu/armv8/start.S
index e933021a17..c1a2f456d5 100644
--- a/arch/arm/cpu/armv8/start.S
+++ b/arch/arm/cpu/armv8/start.S
@@ -21,6 +21,16 @@
b reset
+ * Various SoCs need something special and SoC-specific up front in
+ * order to boot, allow them to set that in their boot0.h file and then
+ * use it here.
+ */
+#include <asm/arch/boot0.h>
.align 3
.globl _TEXT_BASE
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