ACPI: CPPC: Don't require flexible address space if X86_FEATURE_CPPC is supported

Commit 0651ab90e4ad ("ACPI: CPPC: Check _OSC for flexible address space")
changed _CPC probing to require flexible address space to be negotiated
for CPPC to work.

However it was observed that this caused a regression for Arek's ROG
Zephyrus G15 GA503QM which previously CPPC worked, but now it stopped
working.

To avoid causing a regression waive this failure when the CPU is known
to support CPPC.

Cc: Pierre Gondois <pierre.gondois@arm.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216248
Fixes: 0651ab90e4ad ("ACPI: CPPC: Check _OSC for flexible address space")
Reported-and-tested-by: Arek Ruśniak <arek.rusi@gmail.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index 6ff1901..3c6d4ef 100644 (file)
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -782,7 +782,8 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
 
                                        if (!osc_cpc_flexible_adr_space_confirmed) {
                                                pr_debug("Flexible address space capability not supported\n");
-                                               goto out_free;
+                                               if (!cpc_supported_by_cpu())
+                                                       goto out_free;
                                        }
 
                                        addr = ioremap(gas_t->address, gas_t->bit_width/8);
@@ -809,7 +810,8 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
                                }
                                if (!osc_cpc_flexible_adr_space_confirmed) {
                                        pr_debug("Flexible address space capability not supported\n");
-                                       goto out_free;
+                                       if (!cpc_supported_by_cpu())
+                                               goto out_free;
                                }
                        } else {
                                if (gas_t->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE || !cpc_ffh_supported()) {