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Subject[PATCH] Documentation: ARM: EXYNOS: Update bootloader interface on Exynos542x
Date
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>
---
Documentation/arm/Samsung/Bootloader-interface.txt | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/Documentation/arm/Samsung/Bootloader-interface.txt b/Documentation/arm/Samsung/Bootloader-interface.txt
index df8d4fb85939..ed494ac0beb2 100644
--- a/Documentation/arm/Samsung/Bootloader-interface.txt
+++ b/Documentation/arm/Samsung/Bootloader-interface.txt
@@ -19,7 +19,7 @@ executing kernel.
Address: sysram_ns_base_addr
Offset Value Purpose
=============================================================================
-0x08 exynos_cpu_resume_ns System suspend
+0x08 exynos_cpu_resume_ns, mcpm_entry_point System suspend
0x0c 0x00000bad (Magic cookie) System suspend
0x1c exynos4_secondary_startup Secondary CPU boot
0x1c + 4*cpu exynos4_secondary_startup (Exynos4412) Secondary CPU boot
@@ -56,7 +56,8 @@ Offset Value Purpose
Address: pmu_base_addr
Offset Value Purpose
=============================================================================
-0x0908 Non-zero (only Exynos3250) Secondary CPU boot up indicator
+0x0908 Non-zero Secondary CPU boot up indicator
+ on Exynos3250 and Exynos542x


4. Glossary
--
1.9.1


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