Documentation: EXYNOS: Update bootloader interface on exynos542x
Update the documentation about:
1. Usage of PMU_SPARE2 register.
Bootloaders on Exynos542x-based boards often use the register
PMU_SPARE2 (0x908) in the same way as on Exynos3250: as a indicator
the secondary CPU was booted on. The bootloader will set this value
to non-zero, after sucessfull power up of secondary CPU. In the same
time this booted CPU will stuck (spin) waiting for software reset.
2. Exynos542x entry address for secondary CPU boot up after system
suspend (with MCPM enabled and in non-secure mode).
See arch/arm/mach-exynos/mcpm-exynos.c for source code.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>
1 file changed