On 2015/9/28 16:42, Arnd Bergmann wrote: > On Monday 28 September 2015 16:29:57 Leizhen wrote: >> >> On 2015/9/28 15:35, Arnd Bergmann wrote: >>> On Monday 28 September 2015 13:34:38 Zhen Lei wrote: >>>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig >>>> index 07d1811..25cec57 100644 >>>> --- a/arch/arm64/Kconfig >>>> +++ b/arch/arm64/Kconfig >>>> @@ -85,7 +85,7 @@ config ARM64 >>>> select PERF_USE_VMALLOC >>>> select POWER_RESET >>>> select POWER_SUPPLY >>>> - select RTC_LIB >>>> + select RTC_LIB if !EFI >>>> select SPARSE_IRQ >>>> select SYSCTL_EXCEPTION_TRACE >>>> select HAVE_CONTEXT_TRACKING >>> >>> Sorry, we can't do that: enabling EFI has to be done in a way that it only >>> adds features but not disables them. >> >> I run "make ARCH=arm64 menuconfig" and found that RTC_CLASS is selected by >> default. Actually, RTC_LIB only >> controls whether to display some configs when run "make menuconfig". I list >> all informations below: >> >> ---------make ARCH=arm64 menuconfig----- >> [*] Real Time Clock ---> >> >> ---------drivers/rtc/Kconfig------- >> menuconfig RTC_CLASS >> bool "Real Time Clock" >> default n >> depends on !S390 && !UML >> select RTC_LIB > > Ok, I see. So your patch here has no effect at all and can be dropped, or > we can remove the 'select RTC_LIB' without the EFI dependency.
Oh, I described the reason in the reply to Ard Biesheuvel. https://lkml.org/lkml/2015/9/28/124 > >> ----------------------------------- >> find . -name "*Kconfig*" | xargs grep RTC_LIB >> ./drivers/rtc/Kconfig:config RTC_LIB >> ./drivers/rtc/Kconfig: select RTC_LIB >> ./drivers/char/Kconfig:if RTC_LIB=n >> ./drivers/char/Kconfig:endif # RTC_LIB >> ./arch/x86/Kconfig: select RTC_LIB >> ./arch/arm/Kconfig: select RTC_LIB >> ./arch/arm64/Kconfig: select RTC_LIB if !EFI >> ./arch/sh/Kconfig: select RTC_LIB >> ./arch/mips/Kconfig: select RTC_LIB if !MACH_LOONGSON64 >> >> --------------drivers/char/Kconfig-------------- >> if RTC_LIB=n >> >> config RTC >> tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)" >> >> ....... >> >> endif # RTC_LIB >> >> >>> >>> Your patch breaks RTC on all non-EFI platforms as soon as CONFIG_EFI >>> is selected by the user. >> >> No, on non-EFI platforms, they can still use RTC as before. As I mentioned >> above, >> RTC_LIB only controls whether to display some configs when run "make >> menuconfig". >> On ARM64, (in this patch) I only allowed EFI_RTC can be showed when RTC_LIB >> was >> not selected. >> > > but that is the wrong driver that uses the legacy API, we cannot have that > on ARM because it conflicts with the normal RTC_CLASS drivers. Yes, RTC_CLASS will automatically select RTC_LIB, and will not display EFI_RTC, because RTC_LIB=y now. We can select EFI_RTC only when RTC_CLASS is not selected(meanwhile RTC_LIB=n) > >> --------------drivers/char/Kconfig-------------- >> if RTC_LIB=n >> >> config RTC >> tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)" >> >> ....... >> >> config EFI_RTC >> bool "EFI Real Time Clock Services" >> depends on IA64 || ARM64 >> >> ....... >> >> endif # RTC_LIB > > The driver you want is RTC_DRV_EFI, not EFI_RTC. OK, I will try it tommorrow. > > Arnd > > . > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
