Re: [RFC PATCH 0/9] soc: samsung: Add support of suspend-to-RAM on Exynos5433

[Krzysztof Kozlowski]

On Tue, Jan 9, 2018 at 8:58 AM, Chanwoo Choi <cw00.choi@xxxxxxxxxxx> wrote:
> In the mainline, there is no case to support the suspend-to-RAM for Samsung
> Exynos SoC. This patchset support the suspend-to-RAM for 64bit Exynos SoC.
>
> For 32bit, arch/arm/mach-exynos/* directoy contains the suspend-related
> codes such as suspend.c/exynos.c. But, 64bit Exynos should contain
> the suspend-related codes in the drivers/soc/samsung/*. So, this patchset
> develop the patch4/5 for drivers/soc/samsung/exynos-pm.c. to support suspend
> 64bit Exynos SoC.
>
> But, I'm not sure what is proper approach for both 32/64bit Exynos.
> - Approach1 : Split out the supend-related codes between 32/64bit.
>   : arch/arm/mach-exynos/* contains the suspend-related codes for 32bit.
>   : drivers/soc/samsung/* contains the suspend-related codes for 64bit.
> - Approach2 : Consolidate the all suspend-related codes to drivers/soc/samsung/.

I prefer approach #2 - consolidate the code... unless this creates
some unmaintainable monster :)

Best regards,
Krzysztof

>
> Please let us know your opinion.
>
> The patch1/2/3 and 6/7/8/9 is just general patch. So, I add 'RFC' prefix to
> only cover-letter, patch4/5. If you want to add the 'RFC' prefix to all
> patches, I'll add 'RFC' prefix on v2.
>
> Based on:
> - git://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux.git (branch: for-next)
>
> Need to discuss patch4/5:
> - patch4: soc: samsung: Add generic power-management driver for Exynos
> - patch5: soc: samsung: pm: Add support for suspend-to-ram of Exynos5433
>
> [Remaining Issues]
> - The hang-out happen when disabling the MMC clocks on dw_mmc.c.
>   I reported to Jaehoon Chung. He is checking this issue. To test the
>   suspend-to-ram temporarily, you need to add CLK_IS_CRITICAL flag to
>   'aclk_mmc2/aclk_mmc0/sclk_mmc2/sclk_mmc0'.
> - I enabled the at least kernel configuration in order to test
>   the suspend-to-RAM. So, I need to test it more time with DRM/Multimedia
>   and other. But, the suspend-to-RAM of cpu is successful.
> - Exynos5433 SoC has two EXYNOS5433_EINT_WAKEUP_MASKx registers. The
>   pinctr-exynos.c need to handle the extra EINT_WAKEUP_MASKx for Exynos5433.
>   The suspend-to-ram test is failed on first time and then next tryout is ok.
>   I'm developing it.
>
> Chanwoo Choi (9):
>   clk: samsung: exynos5433: Add clock flag to support suspend-to-ram
>   soc: samsung: pmu: Add powerup_conf callback
>   soc: samsung: pmu: Add the PMU data of exynos5433 to support low-power state
>   soc: samsung: Add generic power-management driver for Exynos
>   soc: samsung: pm: Add support for suspend-to-ram of Exynos5433
>   arm64: dts: exynos: Add iRAM device-tree node for Exynos5433
>   arm64: dts: exynos: Use power key as a wakeup source on TM2/TM2E board
>   arm64: dts: exynos: Add cpu_suspend property of PSCI for exynos5433
>   arm64: dts: exynos: Add cpu topology information for Exynos5433 SoC
>
>  arch/arm/mach-exynos/common.h                      |   3 -
>  arch/arm/mach-exynos/exynos.c                      |  23 +-
>  .../boot/dts/exynos/exynos5433-tm2-common.dtsi     |   1 +
>  arch/arm64/boot/dts/exynos/exynos5433.dtsi         |  47 ++++
>  drivers/clk/samsung/clk-exynos5433.c               |  22 +-
>  drivers/soc/samsung/Makefile                       |   5 +-
>  drivers/soc/samsung/exynos-pm.c                    | 214 +++++++++++++++
>  drivers/soc/samsung/exynos-pmu.c                   |   9 +
>  drivers/soc/samsung/exynos-pmu.h                   |   3 +
>  drivers/soc/samsung/exynos5433-pmu.c               | 286 +++++++++++++++++++++
>  include/linux/soc/samsung/exynos-pm.h              |  21 ++
>  include/linux/soc/samsung/exynos-pmu.h             |   1 +
>  include/linux/soc/samsung/exynos-regs-pmu.h        | 148 +++++++++++
>  13 files changed, 745 insertions(+), 38 deletions(-)
>  create mode 100644 drivers/soc/samsung/exynos-pm.c
>  create mode 100644 drivers/soc/samsung/exynos5433-pmu.c
>  create mode 100644 include/linux/soc/samsung/exynos-pm.h
>
> --
> 1.9.1
>