| Message ID | CAP8WD_ZUbO+aKUV1-tPS_5APkpSAwbi=K=koVEDWWUfzF0tW+A@mail.gmail.com (mailing list archive) |
|---|---|
| State | RFC, archived |
| Headers | show |
+Cc: Alan (perhaps he has something to add or correct me) On Tue, Mar 13, 2018 at 1:20 PM, tedheadster <tedheadster@gmail.com> wrote: > Intel PMC Core and CLK API teams, > I am trying to build a minimal kernel config on old > regression-testing hardware. Presently there is the following > drivers/platform/x86/Kconfig item: > > config PMC_ATOM > def_bool y > depends on PCI > select COMMON_CLK > > This creates a cascade of Kconfig "select" statements and pulls in two files: > > drivers/clk/x86/clk-pmc-atom.c > drivers/platform/x86/intel_pmc_core.c > > The Kconfig seems too general to me. Compiling for my i586 Pentium-I > pulls in these files (I think) unnecessarily. Why does _anybody_ with > a PCI bus need these ATOM-specific files? Long story, but main concern here, that if you do s/ATOM/X86/ it will be more clear since we provide as less kernels as possible to cover all x86 architectures. Currently we have one kernel per: - any x86_64 case - any i686 case - uniprocessor i586 TSC case (Intel Quark) - (the rest exotic cases which is probably no-one using anymore) Your change disrupts this quite badly. So, I think your point that you don't need it by default, and here is another story related to the design of Intel BayTrail / CherryTrail platforms where we have a nasty bug and we can't use the driver as a module. > Would this change (or something similar) make sense? No. > --- a/drivers/platform/x86/Kconfig > +++ b/drivers/platform/x86/Kconfig > @@ -1217,5 +1217,5 @@ endif # X86_PLATFORM_DEVICES > > config PMC_ATOM > def_bool y > - depends on PCI > + depends on PCI && MATOM MATOM is for really old CPUs. Mentioned BayTrail et al rather normal x86 in that sense. > select COMMON_CLK Definitely NAK by the reasons mentioned above.
On Tue, Mar 13, 2018 at 1:20 PM, tedheadster <tedheadster@gmail.com> wrote: > drivers/platform/x86/intel_pmc_core.c Apparently you meant pmc_atom.c in the same folder. > config PMC_ATOM
> Long story, but main concern here, that if you do s/ATOM/X86/ it will > be more clear since we provide as less kernels as possible to cover > all x86 architectures. > > Currently we have one kernel per: > - any x86_64 case > - any i686 case > - uniprocessor i586 TSC case (Intel Quark) > - (the rest exotic cases which is probably no-one using anymore) > > Your change disrupts this quite badly. This simplifies your situation, but it forces everybody else to include extra code they will never use. > > So, I think your point that you don't need it by default, and here is > another story related to the design of Intel BayTrail / CherryTrail > platforms where we have a nasty bug and we can't use the driver as a > module. > Please explain the history so we can understand. In more detail, here are the Kconfig dependencies: - Symbol: PMC_ATOM [=y] - Depends on: X86 [=y] && PCI [=y] - Selects: COMMON_CLK [=y] Symbol: COMMON_CLK [=y] - Selected by: PMC_ATOM [=y] && X86 [=y] && PCI [=y] - Selects: HAVE_CLK_PREPARE [=y] && CLKDEV_LOOKUP [=y] && SRCU [=y] && RATIONAL [=y] So having _any_ X86 and PCI pulls in these four files: drivers/clk/x86/clk-pmc-atom.c drivers/platform/x86/pmc_atom.c (you are right, I cut-and-pasted the wrong file earlier) drivers/clk/clkdev.c lib/rational.c >> Would this change (or something similar) make sense? > > No. > Okay, my novice solution isn't the right way. There must be an elegant way to leave this configured in by default (what you want), and still be able to turn it off if you desire (what I want). > MATOM is for really old CPUs. Mentioned BayTrail et al rather normal > x86 in that sense. > >> select COMMON_CLK > > Definitely NAK by the reasons mentioned above. > - Matthew -- To unsubscribe from this list: send the line "unsubscribe linux-clk" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig index d10ffe5..6a026fa 100644 --- a/drivers/platform/x86/Kconfig +++ b/drivers/platform/x86/Kconfig @@ -1217,5 +1217,5 @@ endif # X86_PLATFORM_DEVICES config PMC_ATOM def_bool y - depends on PCI + depends on PCI && MATOM select COMMON_CLK
Intel PMC Core and CLK API teams, I am trying to build a minimal kernel config on old regression-testing hardware. Presently there is the following drivers/platform/x86/Kconfig item: config PMC_ATOM def_bool y depends on PCI select COMMON_CLK This creates a cascade of Kconfig "select" statements and pulls in two files: drivers/clk/x86/clk-pmc-atom.c drivers/platform/x86/intel_pmc_core.c The Kconfig seems too general to me. Compiling for my i586 Pentium-I pulls in these files (I think) unnecessarily. Why does _anybody_ with a PCI bus need these ATOM-specific files? Would this change (or something similar) make sense?