On Thursday 03 March 2016 13:27:59 Geert Uytterhoeven wrote: > On Thu, Mar 3, 2016 at 11:55 AM, Arnd Bergmann <arnd@xxxxxxxx> wrote: > > On Thursday 03 March 2016 17:03:34 Krzysztof Kozlowski wrote: > >> index 0da40e2e4280..5c530b6b125d 100644 > >> --- a/drivers/rtc/Kconfig > >> +++ b/drivers/rtc/Kconfig > >> @@ -1302,6 +1302,7 @@ config RTC_DRV_AT91RM9200 > >> config RTC_DRV_AT91SAM9 > >> tristate "AT91SAM9 RTT as RTC" > >> depends on ARCH_AT91 || COMPILE_TEST > >> + depends on HAS_IOMEM # For MFD_SYSCON > >> select MFD_SYSCON > >> help > >> Some AT91SAM9 SoCs provide an RTT (Real Time Timer) block which > >> > > > > This is technically correct, but the entire RTC menu is hidden > > inside of 'depends on !UML && !S390', so we won't ever get there > > on any configuration that does not use HAS_IOMEM. > > > > If we did, all other RTC drivers would also fail. > > So UML has no RTC. Should/can it use RTC_DRV_GENERIC? I think nothing should use that, even if it could ;-) Funny enough, RTC_DRV_GENERIC would probably actually work if you run UML as root and set iopl() to allow port access, but we don't really want it to mess with the host RTC. I don't know where UML gets it real time, but it doesn't actually need much other than calling clock_gettime(CLOCK_REALTIME, ...) to get the host time. Presumably it uses some variation of that. Arnd -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html