24.05.2021 11:54, Geert Uytterhoeven пишет: > Hi Dmitry, > > On Mon, May 24, 2021 at 1:26 AM Dmitry Osipenko <digetx@xxxxxxxxx> wrote: >> There are couple older platforms that can't be compile-tested because they >> partially implement CLK API. It causes build failure of kernel drivers due >> to the missing symbols of the unimplemented part of CLK API. >> >> These platforms are: ARM EP93XX, ARM OMAP1, m68k ColdFire, MIPS AR7, >> MIPS Ralink. >> >> Disable compile-testing for HAVE_LEGACY_CLK=y. >> >> Reported-by: kernel test robot <lkp@xxxxxxxxx> >> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx> > > Thanks for your patch! > >> --- a/init/Kconfig >> +++ b/init/Kconfig >> @@ -131,7 +131,7 @@ config INIT_ENV_ARG_LIMIT >> >> config COMPILE_TEST >> bool "Compile also drivers which will not load" >> - depends on HAS_IOMEM >> + depends on HAS_IOMEM && !HAVE_LEGACY_CLK > > That sounds a bit drastic to me. Usually we just try to implement the > missing functionality, or provide stubs. > Which functions are missing? Everything that belongs to CONFIG_COMMON_CLK needs stubs. That is everything under CONFIG_HAVE_CLK [1], excluding functions belonging to clk-devres.o and clk-bulk.o [2]. The HAVE_LEGACY_CLK selects HAVE_CLK, but the COMMON_CLK is under HAVE_CLK too. [1] https://elixir.bootlin.com/linux/v5.13-rc3/source/include/linux/clk.h#L786 [2] https://elixir.bootlin.com/linux/v5.13-rc3/source/drivers/clk/Makefile#L3 This problem is repeated over and over again for the past years. Some maintainers are adding "depends on COMMON_CLK" for COMPILE_TEST of each driver, but this doesn't solve the root of the problem, and thus, it's constantly reoccurring. Recently Krzysztof Kozlowski added couple more clk stubs for MIPS, but still lots of stubs are missing. Some platforms don't have any stubs at all and apparently nobody cares to fix them. There 3 possible solutions: 1. Factor out COMMON_CLK from HAVE_LEGACY_CLK, if this is possible 2. Build stubs universally, maybe using weak functions. 3. Disable compile-testing for HAVE_LEGACY_CLK The third option is the simplest. If anyone will care to fix those legacy platforms properly, then compile-testing could be re-enabled for them. This is my proposal.
