On 11 July 2017 at 13:04, Philipp Tomsich philipp.tomsich@theobroma-systems.com wrote:
When building for a TPL/SPL setup (e.g. on the RK3368), we need the TPL stage to have the extra space for for the 'Rockchip SPL name' (i.e. 'RK33' word). Yet, the SPL will start execution at its first word (i.e. the first word in the SPL binary needs to be a valid instruction). To make things a bit more involved, CONFIG_SPL_BUILD is defined both for the SPL and the TPL stage.
To avoid having to explicitly test for the first stage (TPL, if and only if TPL and SPL are built, SPL otherwise), this commit modifies the sequence to repeat the 'b reset' (instead of reserving 4 bytes of undefined space) at the start of the boot0 hook: if overwritten (and execution starts at the second word), the first instruction is still a 'b reset'... if not overwritten, we start on a 'b reset' as well.
This solution wouldn't even require the check whether we are in the SPL/TPL build (i.e. CONFIG_SPL_BUILD), but we leave this check in for documentation purposes.
Signed-off-by: Philipp Tomsich philipp.tomsich@theobroma-systems.com
arch/arm/include/asm/arch-rockchip/boot0.h | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-)
Reviewed-by: Simon Glass sjg@chromium.org