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

From: Mario Limonciello
Date: Fri Jul 15 2022 - 13:33:41 EST


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@xxxxxxx>
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@xxxxxxxxx>
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
drivers/acpi/cppc_acpi.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index 6ff1901d7d43..3c6d4ef87be0 100644
--- 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()) {
--
2.34.1