[PATCH v2 0/2] Firmware-assisted suspend/resume of Exynos SoCs
Tomasz Figa
t.figa at samsung.com
Thu Jul 17 08:56:09 PDT 2014
On Exynos-based boards running secure firmware the sequence of low level
operations to enter and leave system-wide sleep mode is different than
on those without the firmware. Namely:
- CP15 power control and diagnostic registers cannot be written directly,
- the way of setting boot address and boot flag is different,
- different resume handler needs to be used,
- dedicated SMC call needs to be performed instead of letting the CPU enter
WFI.
This series introduces .suspend() and .resume() firmware operations to
perform low level firmware-specific suspend and resume and then leverages
them to provide suspend-resume path meeting the above requirements.
The series is based on Kgene's for-next branch and tested on:
- Exynos4412-based Trats2 board running in non-secure mode (under secure
firmware) with few board-specific fixes that will be sent separately soon,
- Exynos4210-based Trats board running in secure mode,
- Exynos4412-based ODROID-U3 board running in non-secure mode with one minor
board-specific fix which will be send shortly.
Depends on:
- [PATCH v3] ARM: save/restore Cortex-A9 CP15 registers on suspend/resume
(http://www.spinics.net/lists/arm-kernel/msg346212.html)
- [PATCH v3] ARM: EXYNOS: Fix suspend/resume sequences
(https://lkml.org/lkml/2014/7/15/319)
- [PATCH] ARM: make it easier to check the CPU part number correctly
(http://thread.gmane.org/gmane.linux.ports.arm.kernel/335126
already in linux-next)
Changes since v1:
- dropped outer_resume() - will be handled in assembly in further patches,
as support for L2C in non-secure mode gets added,
- moved CP15 resume to assembly as it needs to be done before MMU is enabled,
- surrounded CP15 save with a check for cpuid part, because it is valid only
on Cortex A9,
- rebased on next-20140717 tag of linux-next tree.
Tomasz Figa (2):
ARM: firmware: Introduce suspend and resume operations
ARM: EXYNOS: Add support for firmware-assisted suspend/resume
Documentation/arm/firmware.txt | 28 +++++--------------------
arch/arm/include/asm/firmware.h | 8 ++++++++
arch/arm/mach-exynos/Makefile | 1 +
arch/arm/mach-exynos/common.h | 4 ++++
arch/arm/mach-exynos/firmware.c | 45 +++++++++++++++++++++++++++++++++++++++++
arch/arm/mach-exynos/pm.c | 16 ++++++++++-----
arch/arm/mach-exynos/sleep.S | 28 +++++++++++++++++++++++++
arch/arm/mach-exynos/smc.h | 4 ++++
8 files changed, 106 insertions(+), 28 deletions(-)
--
1.9.3
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