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

From: [email-masked] (Krzysztof Kozlowski)
Date: Sat, 14 Nov 2015 20:30:07 +0900

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.

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?

Best regards,
Krzysztof