14.06.2021 14:50, Krzysztof Kozlowski пишет: > On 11/06/2021 15:40, Dmitry Osipenko wrote: >> 11.06.2021 14:00, Thierry Reding пишет: >>> On Fri, Jun 11, 2021 at 10:21:41AM +0300, Dmitry Osipenko wrote: >>>> 11.06.2021 09:50, Krzysztof Kozlowski пишет: >>>>> On 10/06/2021 18:23, Dmitry Osipenko wrote: >>>>>> 10.06.2021 18:50, Dmitry Osipenko пишет: >>>>>>> 10.06.2021 09:43, Krzysztof Kozlowski пишет: >>>>>>>> The stubs might be good idea anyway, but the driver explicitly needs for >>>>>>>> runtime working reservedmem, so it should select it. >>>>>>> >>>>>>> The OF and reservedmem are both selected by the ARCH for the runtime >>>>>>> use. They may not be selected in the case of compile-testing. >>>>>>> >>>>>>> Both OF core and reservedmem provide stubs needed for compile-testing, >>>>>>> it's only the RESERVEDMEM_OF_DECLARE() that is missing the stub. Adding >>>>>>> the missing stub should be a more appropriate solution than adding extra >>>>>>> Kconfig dependencies, IMO. >>>>> >>>>> Ah, in such case everything looks good. Stubs is indeed proper choice. >>>> >>>> Although, I see that there are only two Kconfigs that have >>>> OF_RESERVED_MEM, one defines the OF_RESERVED_MEM, the other is QCOM >>>> Kconfig which depends on OF_RESERVED_MEM. The OF_RESERVED_MEM is enabled >>>> by default in defconfig. >>>> >>>> You're right, we need the Kconfig change to be entirely correct, since >>>> driver won't work properly without OF_RESERVED_MEM. >>>> >>>> config TEGRA210_EMC >>>> tristate "NVIDIA Tegra210 External Memory Controller driver" >>>> - depends on ARCH_TEGRA_210_SOC || COMPILE_TEST >>>> + depends on (ARCH_TEGRA_210_SOC && OF_RESERVED_MEM) || COMPILE_TEST >>>> >>>> I will send that change later today. >>> >>> That's completely unnecessary. OF_RESERVED_MEM is enabled by default if >>> OF_EARLY_FLATTREE is enabled, which it is for ARM64 and that is always >>> enabled for ARCH_TEGRA_210_SOC. >> >> But it doesn't stop you from disabling OF_RESERVED_MEM. The Kconfig >> dependencies should reflect the build and runtime requirements of the >> driver, otherwise only driver author knows which config options are need. > > OF_RESERVED_MEM is not selectable, so it cannot be disabled for regular > builds. > > When I proposed to add dependencies, I indeed did not check whether > these are selectable symbols. My advise was not accurate. > > Usually we do not add dependencies to each driver on each kernel > non-selectable feature. It would be too much (depends on HAS_IOMEM, > REGMAP, OF, MFD_SYSCON, OF_RESERVED_MEM and probably many more)... There > are of course exceptions and mistakes (I think I should not add > OF_ADDRESS to OMAP_GPMC). > > If such features are non-selectable, usually architecture enforces them > so the driver does not need to. For compile testing, these features > should come with stubs. If there are no stubs, the dependency for > compile testing could be added: > ARCH_TEGRA_210_SOC || (COMPILE_TEST && OF_RESERVED_MEM) > > We add the dependencies for selectable options which driver needs, e.g. > DEVFREQ, CPUFREQ, PM_xxx > > Since you proposed already to add stubs for OF_RESERVED_MEM, adding > dependency on it does not bring any benefit. Right, I also missed that OF_RESERVED_MEM is non-selectable.
