[ACPI] handle BIOS with implicit C1 in _CST
The ASUS M6Ne specifies C2, implying C1
but not explicitly specifying it.
http://bugzilla.kernel.org/show_bug.cgi?id=4485
Signed-off-by: Janosch Machowinski <jmachowinski@gmx.de>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 83fd1b6..40c9f9ca 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -532,18 +532,10 @@
if (!pr->pblk)
return_VALUE(-ENODEV);
- memset(pr->power.states, 0, sizeof(pr->power.states));
-
/* if info is obtained from pblk/fadt, type equals state */
- pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1;
pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2;
pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3;
- /* the C0 state only exists as a filler in our array,
- * and all processors need to support C1 */
- pr->power.states[ACPI_STATE_C0].valid = 1;
- pr->power.states[ACPI_STATE_C1].valid = 1;
-
#ifndef CONFIG_HOTPLUG_CPU
/*
* Check for P_LVL2_UP flag before entering C2 and above on
@@ -573,12 +565,11 @@
{
ACPI_FUNCTION_TRACE("acpi_processor_get_power_info_default_c1");
+ /* Zero initialize all the C-states info. */
memset(pr->power.states, 0, sizeof(pr->power.states));
- /* if info is obtained from pblk/fadt, type equals state */
+ /* set the first C-State to C1 */
pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1;
- pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2;
- pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3;
/* the C0 state only exists as a filler in our array,
* and all processors need to support C1 */
@@ -592,6 +583,7 @@
{
acpi_status status = 0;
acpi_integer count;
+ int current_count;
int i;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *cst;
@@ -601,10 +593,12 @@
if (nocst)
return_VALUE(-ENODEV);
- pr->power.count = 0;
- for (i = 0; i < ACPI_PROCESSOR_MAX_POWER; i++)
- memset(&(pr->power.states[i]), 0,
- sizeof(struct acpi_processor_cx));
+ current_count = 1;
+
+ /* Zero initialize C2 onwards and prepare for fresh CST lookup */
+ for (i = 2; i < ACPI_PROCESSOR_MAX_POWER; i++)
+ memset(&(pr->power.states[i]), 0,
+ sizeof(struct acpi_processor_cx));
status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer);
if (ACPI_FAILURE(status)) {
@@ -632,16 +626,6 @@
goto end;
}
- /* We support up to ACPI_PROCESSOR_MAX_POWER. */
- if (count > ACPI_PROCESSOR_MAX_POWER) {
- printk(KERN_WARNING
- "Limiting number of power states to max (%d)\n",
- ACPI_PROCESSOR_MAX_POWER);
- printk(KERN_WARNING
- "Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n");
- count = ACPI_PROCESSOR_MAX_POWER;
- }
-
/* Tell driver that at least _CST is supported. */
pr->flags.has_cst = 1;
@@ -685,7 +669,7 @@
(reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO))
continue;
- if ((cx.type < ACPI_STATE_C1) || (cx.type > ACPI_STATE_C3))
+ if ((cx.type < ACPI_STATE_C2) || (cx.type > ACPI_STATE_C3))
continue;
obj = (union acpi_object *)&(element->package.elements[2]);
@@ -700,15 +684,28 @@
cx.power = obj->integer.value;
- (pr->power.count)++;
- memcpy(&(pr->power.states[pr->power.count]), &cx, sizeof(cx));
+ current_count++;
+ memcpy(&(pr->power.states[current_count]), &cx, sizeof(cx));
+
+ /*
+ * We support total ACPI_PROCESSOR_MAX_POWER - 1
+ * (From 1 through ACPI_PROCESSOR_MAX_POWER - 1)
+ */
+ if (current_count >= (ACPI_PROCESSOR_MAX_POWER - 1)) {
+ printk(KERN_WARNING
+ "Limiting number of power states to max (%d)\n",
+ ACPI_PROCESSOR_MAX_POWER);
+ printk(KERN_WARNING
+ "Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n");
+ break;
+ }
}
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d power states\n",
- pr->power.count));
+ current_count));
/* Validate number of power states discovered */
- if (pr->power.count < 2)
+ if (current_count < 2)
status = -EFAULT;
end:
@@ -859,12 +856,13 @@
/* NOTE: the idle thread may not be running while calling
* this function */
+ /* Adding C1 state */
+ acpi_processor_get_power_info_default_c1(pr);
result = acpi_processor_get_power_info_cst(pr);
if (result == -ENODEV)
- result = acpi_processor_get_power_info_fadt(pr);
+ acpi_processor_get_power_info_fadt(pr);
- if ((result) || (acpi_processor_power_verify(pr) < 2))
- result = acpi_processor_get_power_info_default_c1(pr);
+ pr->power.count = acpi_processor_power_verify(pr);
/*
* Set Default Policy