[U-Boot] Antwort: Re: Re: [PATCH] x86: tsc: Add support for APL soc

[Bernhard Messerklinger]

> > > > > > Are you saying that if doing cpu_mhz_from_cpuid() you can't 
get
> > > > > > correct frequency? Can you investigate why your core crystal 
clock
> > is
> > > > > > always zero?
> > > > >
> > > > > Yes, this has to be investigated.
> > > > >
> > > > > > Can we do it something like VLV2?
> > > > >
> > > > > Please, don't. I see no evidence in the latest Linux kernel 
sources
> > > > > that Apollo Lake has such issue as Intel MID family of Atom 
SoCs.
> > > >
> > > > Sorry, I slipped one code in my consideration, i.e.
> > > >
> > > > unsigned long native_calibrate_tsc(void)
> > > > {
> > > > ...
> > > > if (crystal_khz == 0) {
> > > > switch (boot_cpu_data.x86_model) {
> > > > ...
> > > > case INTEL_FAM6_ATOM_GOLDMONT:
> > > > crystal_khz = 19200; /* 19.2 MHz */
> > > > break;
> > > > }
> > > > ...
> > > > if (boot_cpu_data.x86_model == INTEL_FAM6_ATOM_GOLDMONT)
> > > > setup_force_cpu_cap(X86_FEATURE_TSC_RELIABLE);
> > > > ...
> > > > }
> > > >
> > > > So, that's what we need to do in U-boot.
> > > >
> > >
> > > Thanks for the investigation. Could you please send a proper patch?
> > do you want to take charge of this?
> > Otherwise I will post patch V2.
> 
> I'm busy with something else, so, if you don't mind, please, consider
> v2 which takes into consideration my findings.
Ok, as soon as I am done I will post v2.

--
Best Regards,
Bernhard