On Thu, Jun 29, 2023 at 1:04 PM Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote:
>
> I would just say "Introduce acpi_processor_osc()" in the subject and
> then explain its role in the changelog.
>
> On Tue, Jun 13, 2023 at 6:12 PM Michal Wilczynski
> <michal.wilczynski@xxxxxxxxx> wrote:
> >
> > Currently in ACPI code _OSC method is already used for workaround
> > introduced in commit a21211672c9a ("ACPI / processor: Request native
> > thermal interrupt handling via _OSC"). Create new function, similar to
> > already existing acpi_hwp_native_thermal_lvt_osc(). Call new function
> > acpi_processor_osc(). Make this function fulfill the purpose previously
> > fulfilled by the workaround plus convey OSPM processor capabilities
> > with it by setting correct processor capability bits.
> >
> > Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> > Signed-off-by: Michal Wilczynski <michal.wilczynski@xxxxxxxxx>
> > Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> > ---
> > arch/x86/include/asm/acpi.h | 3 +++
> > drivers/acpi/acpi_processor.c | 43 ++++++++++++++++++++++++++++++++++-
> > include/acpi/pdc_intel.h | 1 +
> > 3 files changed, 46 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h
> > index 6a498d1781e7..6c25ce2dad18 100644
> > --- a/arch/x86/include/asm/acpi.h
> > +++ b/arch/x86/include/asm/acpi.h
> > @@ -112,6 +112,9 @@ static inline void arch_acpi_set_proc_cap_bits(u32 *cap)
> > if (cpu_has(c, X86_FEATURE_ACPI))
> > *cap |= ACPI_PDC_T_FFH;
> >
> > + if (cpu_has(c, X86_FEATURE_HWP))
> > + *cap |= ACPI_PDC_COLLAB_PROC_PERF;
> > +
> > /*
> > * If mwait/monitor is unsupported, C2/C3_FFH will be disabled
> > */
> > diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
> > index 8c5d0295a042..0de0b05b6f53 100644
> > --- a/drivers/acpi/acpi_processor.c
> > +++ b/drivers/acpi/acpi_processor.c
> > @@ -591,13 +591,54 @@ void __init processor_dmi_check(void)
> > dmi_check_system(processor_idle_dmi_table);
> > }
> >
> > +/* vendor specific UUID indicating an Intel platform */
> > +static u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
> > static bool acpi_hwp_native_thermal_lvt_set;
> > +static acpi_status __init acpi_processor_osc(acpi_handle handle, u32 lvl,
> > + void *context, void **rv)
> > +{
> > + u32 capbuf[2] = {};
> > + acpi_status status;
> > + struct acpi_osc_context osc_context = {
> > + .uuid_str = sb_uuid_str,
> > + .rev = 1,
> > + .cap.length = 8,
> > + .cap.pointer = capbuf,
> > + };
> > +
> > + if (processor_physically_present(handle) == false)
>
> if (!processor_physically_present(handle))
>
> > + return AE_OK;
> > +
> > + arch_acpi_set_proc_cap_bits(&capbuf[OSC_SUPPORT_DWORD]);
> > +
> > + if (boot_option_idle_override == IDLE_NOMWAIT)
> > + capbuf[OSC_SUPPORT_DWORD] &=
> > + ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
> > +
> > + status = acpi_run_osc(handle, &osc_context);
> > + if (ACPI_FAILURE(status))
> > + return status;
> > +
> > + if (osc_context.ret.pointer && osc_context.ret.length > 1) {
> > + u32 *capbuf_ret = osc_context.ret.pointer;
> > +
> > + if (!acpi_hwp_native_thermal_lvt_set &&
> > + capbuf_ret[1] & ACPI_PDC_COLLAB_PROC_PERF) {
>
> Checking it in capbuf_ret[] if it was not set in capbuf[] is sort of
> questionable.
>
> Note that acpi_hwp_native_thermal_lvt_osc() sets it in capbuf[] before
> calling acpi_run_osc().
So you moved setting it to arch_acpi_set_proc_cap_bits(), but then it
should also be checked by the arch code. That is, add an arch
function to check if a given bit is set in the returned capabilities
buffer (passed as an argument).
Also it can be argued that ACPI_PDC_C_C2C3_FFH and ACPI_PDC_C_C1_FFH
should be set by the arch code too.
>
> > + acpi_handle_info(handle,
> > + "_OSC native thermal LVT Acked\n");
> > + acpi_hwp_native_thermal_lvt_set = true;
> > + }
> > + }
> > + kfree(osc_context.ret.pointer);
> > +
> > + return AE_OK;
> > +}
> > +
> > static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,
> > u32 lvl,
> > void *context,
> > void **rv)
> > {
> > - u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
> > u32 capbuf[2];
> > struct acpi_osc_context osc_context = {
> > .uuid_str = sb_uuid_str,
> > diff --git a/include/acpi/pdc_intel.h b/include/acpi/pdc_intel.h
> > index 967c552d1cd3..9427f639287f 100644
> > --- a/include/acpi/pdc_intel.h
> > +++ b/include/acpi/pdc_intel.h
> > @@ -16,6 +16,7 @@
> > #define ACPI_PDC_C_C1_FFH (0x0100)
> > #define ACPI_PDC_C_C2C3_FFH (0x0200)
> > #define ACPI_PDC_SMP_P_HWCOORD (0x0800)
> > +#define ACPI_PDC_COLLAB_PROC_PERF (0x1000)
>
> I would call this ACPI_OSC_COLLAB_PROC_PERF to avoid confusion.
>
> It may also be a good idea to introduce ACPI_OSC_ symbols to replace
> the existing ACPI_PDC_ ones (with the same values, respectively) and
> get rid of the latter later.
>
> > #define ACPI_PDC_EST_CAPABILITY_SMP (ACPI_PDC_SMP_C1PT | \
> > ACPI_PDC_C_C1_HALT | \
> > --
