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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-11 10:41:07 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-13 08:17:18 +0300
commite09b41010ba33a20a87472ee821fa407a5b8da36 (patch)
treed10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/Documentation/arm/Samsung
parentf93b97fd65072de626c074dbe099a1fff05ce060 (diff)
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page. During the rebasing, the following patch collided: Force tick interrupt and get rid of softirq magic(I70131fb85). Collisions have been removed because its logic was found on the source already. Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769 Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/Documentation/arm/Samsung')
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diff --git a/kernel/Documentation/arm/Samsung/Bootloader-interface.txt b/kernel/Documentation/arm/Samsung/Bootloader-interface.txt
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+ Interface between kernel and boot loaders on Exynos boards
+ ==========================================================
+
+Author: Krzysztof Kozlowski
+Date : 6 June 2015
+
+The document tries to describe currently used interface between Linux kernel
+and boot loaders on Samsung Exynos based boards. This is not a definition
+of interface but rather a description of existing state, a reference
+for information purpose only.
+
+In the document "boot loader" means any of following: U-boot, proprietary
+SBOOT or any other firmware for ARMv7 and ARMv8 initializing the board before
+executing kernel.
+
+
+1. Non-Secure mode
+
+Address: sysram_ns_base_addr
+Offset Value Purpose
+=============================================================================
+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
+0x20 0xfcba0d10 (Magic cookie) AFTR
+0x24 exynos_cpu_resume_ns AFTR
+0x28 + 4*cpu 0x8 (Magic cookie, Exynos3250) AFTR
+
+
+2. Secure mode
+
+Address: sysram_base_addr
+Offset Value Purpose
+=============================================================================
+0x00 exynos4_secondary_startup Secondary CPU boot
+0x04 exynos4_secondary_startup (Exynos542x) Secondary CPU boot
+4*cpu exynos4_secondary_startup (Exynos4412) Secondary CPU boot
+0x20 exynos_cpu_resume (Exynos4210 r1.0) AFTR
+0x24 0xfcba0d10 (Magic cookie, Exynos4210 r1.0) AFTR
+
+Address: pmu_base_addr
+Offset Value Purpose
+=============================================================================
+0x0800 exynos_cpu_resume AFTR, suspend
+0x0800 mcpm_entry_point (Exynos542x with MCPM) AFTR, suspend
+0x0804 0xfcba0d10 (Magic cookie) AFTR
+0x0804 0x00000bad (Magic cookie) System suspend
+0x0814 exynos4_secondary_startup (Exynos4210 r1.1) Secondary CPU boot
+0x0818 0xfcba0d10 (Magic cookie, Exynos4210 r1.1) AFTR
+0x081C exynos_cpu_resume (Exynos4210 r1.1) AFTR
+
+
+3. Other (regardless of secure/non-secure mode)
+
+Address: pmu_base_addr
+Offset Value Purpose
+=============================================================================
+0x0908 Non-zero Secondary CPU boot up indicator
+ on Exynos3250 and Exynos542x
+
+
+4. Glossary
+
+AFTR - ARM Off Top Running, a low power mode, Cortex cores and many other
+modules are power gated, except the TOP modules
+MCPM - Multi-Cluster Power Management