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authorLen Brown <len.brown@intel.com>2007-07-22 02:27:40 -0400
committerLen Brown <len.brown@intel.com>2007-07-22 02:27:40 -0400
commitf79e3185dd0f8650022518d7624c876d8929061b (patch)
tree4cec3a434036031b4e2d4fef608f5523fb21c829 /drivers/acpi/processor_idle.c
parente8b495fe09bc793ae26774e7b2667f7f658d56e2 (diff)
parent8b8eb7d8cfc6cd95ed00cd58754e8493322505bd (diff)
Pull misc into release branch
Conflicts: Documentation/feature-removal-schedule.txt
Diffstat (limited to 'drivers/acpi/processor_idle.c')
-rw-r--r--drivers/acpi/processor_idle.c20
1 files changed, 15 insertions, 5 deletions
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index bb5d23be4260..a898991f77cb 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -490,7 +490,17 @@ static void acpi_processor_idle(void)
case ACPI_STATE_C3:
- if (pr->flags.bm_check) {
+ /*
+ * disable bus master
+ * bm_check implies we need ARB_DIS
+ * !bm_check implies we need cache flush
+ * bm_control implies whether we can do ARB_DIS
+ *
+ * That leaves a case where bm_check is set and bm_control is
+ * not set. In that case we cannot do much, we enter C3
+ * without doing anything.
+ */
+ if (pr->flags.bm_check && pr->flags.bm_control) {
if (atomic_inc_return(&c3_cpu_count) ==
num_online_cpus()) {
/*
@@ -499,7 +509,7 @@ static void acpi_processor_idle(void)
*/
acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1);
}
- } else {
+ } else if (!pr->flags.bm_check) {
/* SMP with no shared cache... Invalidate cache */
ACPI_FLUSH_CPU_CACHE();
}
@@ -511,7 +521,7 @@ static void acpi_processor_idle(void)
acpi_cstate_enter(cx);
/* Get end time (ticks) */
t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
- if (pr->flags.bm_check) {
+ if (pr->flags.bm_check && pr->flags.bm_control) {
/* Enable bus master arbitration */
atomic_dec(&c3_cpu_count);
acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0);
@@ -961,9 +971,9 @@ static void acpi_processor_power_verify_c3(struct acpi_processor *pr,
if (pr->flags.bm_check) {
/* bus mastering control is necessary */
if (!pr->flags.bm_control) {
+ /* In this case we enter C3 without bus mastering */
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
- "C3 support requires bus mastering control\n"));
- return;
+ "C3 support without bus mastering control\n"));
}
} else {
/*