[U-Boot] [PATCH for 2018.03] sunxi: README.sunxi64: Add hint about non-debug ATF

[Andre Przywara]

As we are running into issues where the final U-Boot FIT image file is
exceeding our size limit, add a hint to the README.sunxi64 file
to point out the possibility of building non-debug versions of the ATF
binary. This is about 12KB smaller than the standard debug build, and
so again allows successful U-Boot builds for many boards with the
Allwinner H5 SoC.
Please note that under normal circumstances the debug build is still
recommended, as it gives valuable clues in case something goes wrong in
the ATF.

Signed-off-by: Andre Przywara <andre.przywara at arm.com>
---
Hi,

as the level of desperation about Allwinner 64-bit FIT image sizes rises,
we are getting more into the slightly cheaty section with our mitigations.
However as my previous attempts in fixing this issue were not that warmly
welcomed, I now suggest this rather pragmatic solution, which avoids hacking
U-Boot badly. This fixes the various H5 builds for me.

Cheers,
Andre.

 board/sunxi/README.sunxi64 | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/board/sunxi/README.sunxi64 b/board/sunxi/README.sunxi64
index c492f749b8..eefa5001a2 100644
--- a/board/sunxi/README.sunxi64
+++ b/board/sunxi/README.sunxi64
@@ -38,6 +38,12 @@ the root of your U-Boot build directory (or create a symbolic link).
 $ export BL31=/src/arm-trusted-firmware/build/sun50iw1p1/debug/bl31.bin
   (adjust the actual path accordingly)
 
+If you run into size issues with the resulting U-Boot image file, it might
+help to use a release build, by using "DEBUG=0" when building bl31.bin.
+As sometimes the ATF build process is a bit picky about the toolchain used,
+or if you can't be bothered with building ATF, there are known working
+binaries in the firmware repository[3], purely for convenience reasons.
+
  SPL/U-Boot
 ------------
 Both U-Boot proper and the SPL are using the 64-bit mode. As the boot ROM
-- 
2.14.1