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ACPI: enable MWAIT for C1 idle

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Add MWAIT idle for C1 state instead of halt, on platforms that support
C1 state with MWAIT.

Renames cx->space_id to something more appropriate.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
venkatesh.pallipadi@intel.com 2008-01-31 17:35:04 -08:00 committed by Len Brown
parent 2e906655ba
commit bc71bec91f
2 changed files with 14 additions and 9 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

20
drivers/acpi/processor_idle.c
View file

@ -265,7 +265,7 @@ static atomic_t c3_cpu_count;
/* Common C-state entry for C2, C3, .. */
static void acpi_cstate_enter(struct acpi_processor_cx *cstate)
{
if (cstate->space_id == ACPI_CSTATE_FFH) {
if (cstate->entry_method == ACPI_CSTATE_FFH) {
/* Call into architectural FFH based C-state */
acpi_processor_ffh_cstate_enter(cstate);
} else {
@ -929,20 +929,20 @@ static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
cx.address = reg->address;
cx.index = current_count + 1;
cx.space_id = ACPI_CSTATE_SYSTEMIO;
cx.entry_method = ACPI_CSTATE_SYSTEMIO;
if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
if (acpi_processor_ffh_cstate_probe
(pr->id, &cx, reg) == 0) {
cx.space_id = ACPI_CSTATE_FFH;
} else if (cx.type != ACPI_STATE_C1) {
cx.entry_method = ACPI_CSTATE_FFH;
} else if (cx.type == ACPI_STATE_C1) {
/*
* C1 is a special case where FIXED_HARDWARE
* can be handled in non-MWAIT way as well.
* In that case, save this _CST entry info.
* That is, we retain space_id of SYSTEM_IO for
* halt based C1.
* Otherwise, ignore this info and continue.
*/
cx.entry_method = ACPI_CSTATE_HALT;
} else {
continue;
}
}
@ -1376,12 +1376,16 @@ static inline void acpi_idle_update_bm_rld(struct acpi_processor *pr,
/**
* acpi_idle_do_entry - a helper function that does C2 and C3 type entry
* @cx: cstate data
*
* Caller disables interrupt before call and enables interrupt after return.
*/
static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx)
{
if (cx->space_id == ACPI_CSTATE_FFH) {
if (cx->entry_method == ACPI_CSTATE_FFH) {
/* Call into architectural FFH based C-state */
acpi_processor_ffh_cstate_enter(cx);
} else if (cx->entry_method == ACPI_CSTATE_HALT) {
acpi_safe_halt();
} else {
int unused;
/* IO port based C-state */
@ -1414,7 +1418,7 @@ static int acpi_idle_enter_c1(struct cpuidle_device *dev,
if (pr->flags.bm_check)
acpi_idle_update_bm_rld(pr, cx);
acpi_safe_halt();
acpi_idle_do_entry(cx);
local_irq_enable();
cx->usage++;

3
include/acpi/processor.h
View file

@ -34,6 +34,7 @@
#define ACPI_CSTATE_SYSTEMIO (0)
#define ACPI_CSTATE_FFH (1)
#define ACPI_CSTATE_HALT (2)
/* Power Management */
@ -64,7 +65,7 @@ struct acpi_processor_cx {
u8 valid;
u8 type;
u32 address;
u8 space_id;
u8 entry_method;
u8 index;
u32 latency;
u32 latency_ticks;