Currently arch_acpi_set_proc_cap_bits() clears ACPI_PDC_C_C2C3_FFH bit in
case MWAIT instruction is not supported. It should also clear
ACPI_PDC_C_C1_FFH, as when MWAIT is not supported C1 is accomplished
with HALT instruction. Quote from documentation describing C_C1_FFH:
"If set, OSPM is capable of performing native C State instructions (beyond
halt) for the C1 handler in multi-processor configurations". As without
MWAIT there is no native C-state instructions beyond HALT, this bit
should be toggled off.
Clear ACPI_PDC_C_C1_FFH and ACPI_PDC_C_C2C3_FFH in
arch_acpi_set_proc_cap_bits() in case MWAIT is not supported or overridden.
Remove setting those bits in processor_pdc.c code.
Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Michal Wilczynski <michal.wilczynski@xxxxxxxxx>
---
arch/x86/include/asm/acpi.h | 9 +++++----
drivers/acpi/processor_pdc.c | 14 --------------
2 files changed, 5 insertions(+), 18 deletions(-)
diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h
index ce5ad6a496e6..d615238bcd78 100644
--- a/arch/x86/include/asm/acpi.h
+++ b/arch/x86/include/asm/acpi.h
@@ -113,11 +113,12 @@ static inline void arch_acpi_set_proc_cap_bits(u32 *cap)
*cap |= ACPI_PROC_CAP_T_FFH;
/*
- * If mwait/monitor is unsupported, C2/C3_FFH will be disabled
+ * If mwait/monitor is unsupported, C_C1_FFH and
+ * C2/C3_FFH will be disabled.
*/
- if (!cpu_has(c, X86_FEATURE_MWAIT))
- *cap &= ~(ACPI_PROC_CAP_C_C2C3_FFH);
-
+ if (!cpu_has(c, X86_FEATURE_MWAIT) ||
+ boot_option_idle_override == IDLE_NOMWAIT)
+ *cap &= ~(ACPI_PROC_CAP_C_C1_FFH | ACPI_PROC_CAP_C_C2C3_FFH);
}
static inline bool acpi_has_cpu_in_madt(void)
diff --git a/drivers/acpi/processor_pdc.c b/drivers/acpi/processor_pdc.c
index 77d3fe73047c..b4b906b70a0b 100644
--- a/drivers/acpi/processor_pdc.c
+++ b/drivers/acpi/processor_pdc.c
@@ -74,20 +74,6 @@ acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
{
acpi_status status = AE_OK;
- if (boot_option_idle_override == IDLE_NOMWAIT) {
- /*
- * If mwait is disabled for CPU C-states, the C2C3_FFH access
- * mode will be disabled in the parameter of _PDC object.
- * Of course C1_FFH access mode will also be disabled.
- */
- union acpi_object *obj;
- u32 *buffer = NULL;
-
- obj = pdc_in->pointer;
- buffer = (u32 *)(obj->buffer.pointer);
- buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
-
- }
status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
if (ACPI_FAILURE(status))
--
2.41.0
