Subject: [PATCH v5 9/9] drivers: soc: Add support for Exynos PMU driver

From: [email-masked] (pankaj.dubey)
Date: Tue, 17 Nov 2015 09:14:39 +0530

On Saturday 14 November 2015 05:00 PM, Krzysztof Kozlowski wrote:
> W dniu 14.11.2015 o 00:36, Pankaj Dubey pisze:
>> On 13 November 2015 at 15:58, Krzysztof Kozlowski
>> <[email-masked]> wrote:
>>>
>>> On 13.11.2015 18:29, Pankaj Dubey wrote:
>>>> This patch moves Exynos PMU driver implementation from "arm/mach-exynos"
>>>> to "drivers/soc/samsung". This driver is mainly used for setting misc
>>>> bits of register from PMU IP of Exynos SoC which will be required to
>>>> configure before Suspend/Resume. Currently all these settings are done
>>>> in "arch/arm/mach-exynos/pmu.c" but moving ahead for ARM64 based SoC
>>>> support, there is a need of this PMU driver in driver/* folder.
>>>>
>>>> This driver uses existing DT binding information and there should
>>>> be no functionality change in the supported platforms.
>>>>
>>>> Signed-off-by: Amit Daniel Kachhap <[email-masked]>
>>>> Signed-off-by: Pankaj Dubey <[email-masked]>
>>>> ---
>>>>   arch/arm/mach-exynos/Kconfig                                   | 1 +
>>>>   arch/arm/mach-exynos/Makefile                                  | 4 +---
>>>>   drivers/soc/samsung/Kconfig                                    | 4 ++++
>>>>   drivers/soc/samsung/Makefile                                   | 4 ++++
>>>>   arch/arm/mach-exynos/pmu.c => drivers/soc/samsung/exynos-pmu.c | 0
>>>>   {arch/arm/mach-exynos => drivers/soc/samsung}/exynos-pmu.h     | 0
>>>>   {arch/arm/mach-exynos => drivers/soc/samsung}/exynos3250-pmu.c | 0
>>>>   {arch/arm/mach-exynos => drivers/soc/samsung}/exynos4-pmu.c    | 0
>>>>   {arch/arm/mach-exynos => drivers/soc/samsung}/exynos5250-pmu.c | 0
>>>>   {arch/arm/mach-exynos => drivers/soc/samsung}/exynos5420-pmu.c | 0
>>>>   10 files changed, 10 insertions(+), 3 deletions(-)
>>>>   rename arch/arm/mach-exynos/pmu.c => drivers/soc/samsung/exynos-pmu.c (100%)
>>>>   rename {arch/arm/mach-exynos => drivers/soc/samsung}/exynos-pmu.h (100%)
>>>>   rename {arch/arm/mach-exynos => drivers/soc/samsung}/exynos3250-pmu.c (100%)
>>>>   rename {arch/arm/mach-exynos => drivers/soc/samsung}/exynos4-pmu.c (100%)
>>>>   rename {arch/arm/mach-exynos => drivers/soc/samsung}/exynos5250-pmu.c (100%)
>>>>   rename {arch/arm/mach-exynos => drivers/soc/samsung}/exynos5420-pmu.c (100%)
>>>>
>>>> diff --git a/arch/arm/mach-exynos/Kconfig b/arch/arm/mach-exynos/Kconfig
>>>> index 83c85f5..874cb38 100644
>>>> --- a/arch/arm/mach-exynos/Kconfig
>>>> +++ b/arch/arm/mach-exynos/Kconfig
>>>> @@ -16,6 +16,7 @@ menuconfig ARCH_EXYNOS
>>>>        select ARM_GIC
>>>>        select COMMON_CLK_SAMSUNG
>>>>        select EXYNOS_THERMAL
>>>> +     select EXYNOS_PMU
>>>>        select EXYNOS_SROM if PM
>>>>        select HAVE_ARM_SCU if SMP
>>>>        select HAVE_S3C2410_I2C if I2C
>>>> diff --git a/arch/arm/mach-exynos/Makefile b/arch/arm/mach-exynos/Makefile
>>>> index 2d58063..34d29df 100644
>>>> --- a/arch/arm/mach-exynos/Makefile
>>>> +++ b/arch/arm/mach-exynos/Makefile
>>>> @@ -9,9 +9,7 @@ ccflags-$(CONFIG_ARCH_MULTIPLATFORM) += -I$(srctree)/$(src)/include -I$(srctree)
>>>>
>>>>   # Core
>>>>
>>>> -obj-$(CONFIG_ARCH_EXYNOS)    += exynos.o pmu.o exynos-smc.o firmware.o \
>>>> -                                     exynos3250-pmu.o exynos4-pmu.o \
>>>> -                                     exynos5250-pmu.o exynos5420-pmu.o
>>>> +obj-$(CONFIG_ARCH_EXYNOS)    += exynos.o exynos-smc.o firmware.o
>>>>
>>>>   obj-$(CONFIG_EXYNOS_CPU_SUSPEND) += pm.o sleep.o
>>>>   obj-$(CONFIG_PM_SLEEP)               += suspend.o
>>>> diff --git a/drivers/soc/samsung/Kconfig b/drivers/soc/samsung/Kconfig
>>>> index 2833b5b..f545d6c 100644
>>>> --- a/drivers/soc/samsung/Kconfig
>>>> +++ b/drivers/soc/samsung/Kconfig
>>>> @@ -10,4 +10,8 @@ config EXYNOS_SROM
>>>>        bool
>>>>        depends on ARM && ARCH_EXYNOS && PM
>>>>
>>>> +config EXYNOS_PMU
>>>> +     bool
>>>> +     depends on ARCH_EXYNOS
>>>> +
>>>>   endmenu
>>>> diff --git a/drivers/soc/samsung/Makefile b/drivers/soc/samsung/Makefile
>>>> index 9c554d5..26fb489 100644
>>>> --- a/drivers/soc/samsung/Makefile
>>>> +++ b/drivers/soc/samsung/Makefile
>>>> @@ -1 +1,5 @@
>>>>   obj-$(CONFIG_EXYNOS_SROM)    += exynos-srom.o
>>>> +ifdef CONFIG_ARM
>>>> +obj-$(CONFIG_EXYNOS_PMU)     += exynos-pmu.o exynos3250-pmu.o exynos4-pmu.o \
>>>> +                                     exynos5250-pmu.o exynos5420-pmu.o
>>>> +endif
>>>
>>> Why ifdef CONFIG_ARM? This already depends on ARCH_EXYNOS. If you want
>>> to limit to ARMv7 then add the dependency to Kconfig (just like
>>> EXYNOS_SROM).
>>>
>>
>> This is required, so that 32-bit based Exynos SoC's PMU should not get
>> compiled when we are compiling for ARM64 and vice-versa.
>>
>> For example: In future, I have plan to add exynos7 PMU support as -
>>
>> ifdef CONFIG_ARM64
>> obj-$(CONFIG_EXYNOS_PMU) += exynos-pmu.o exynos7-pmu.o
>> endif
>>
>> Thus preventing compilation of ARM64 based SoCs PMU data files when we
>> are compiling for ARM.
>>
>> Only exynos-pmu.c will be shared and compiled in both cases.
>
> But this actually spreads Kconfig configuration over different places:
> Kconfig and Makefile. It confuses and makes it more difficult in the
> future to maintain and extend.
>

I could not understand your point here. Will you please explain what 
issue you can see in this approach?

> This should be in Kconfig. If you want to limit this per architecture
> (is it really needed?) then maybe define different EXYNOS_PMU config
> symbols?
>

Do you mean we need to have separate configs for enabling PMU on ARM and 
ARM64 based Exynos SoCs?

Thanks,
Pankaj Dubey
> Best regards,
> Krzysztof