OMAP3: cpuidle: change the power domains modes determination logic

The achievable power modes of the power domains in cpuidle
depends on the system wide 'enable_off_mode' knob in debugfs.
Upon changing enable_off_mode, do not change the C-states
'valid' field but instead dynamically restrict the power modes
when entering idle.

The C-states 'valid' field is just used to enable/disable some
C-states at init and shall not be changed later on.

Signed-off-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>

1 files changed, 24 insertions, 34 deletions

diff --git a/arch/arm/mach-omap2/cpuidle34xx.c b/arch/arm/mach-omap2/cpuidle34xx.c
index dd31e539274c..4bf6e6e8b100 100644
--- a/arch/arm/mach-omap2/cpuidle34xx.c
+++ b/arch/arm/mach-omap2/cpuidle34xx.c
@@ -138,22 +138,40 @@ return_sleep_time:
 }
 
 /**
- * next_valid_state - Find next valid c-state
+ * next_valid_state - Find next valid C-state
  * @dev: cpuidle device
- * @state: Currently selected c-state
+ * @state: Currently selected C-state
  *
  * If the current state is valid, it is returned back to the caller.
  * Else, this function searches for a lower c-state which is still
  * valid.
+ *
+ * A state is valid if the 'valid' field is enabled and
+ * if it satisfies the enable_off_mode condition.
  */
 static struct cpuidle_state *next_valid_state(struct cpuidle_device *dev,
                                               struct cpuidle_state *curr)
 {
         struct cpuidle_state *next = NULL;
         struct omap3_idle_statedata *cx = cpuidle_get_statedata(curr);
+        u32 mpu_deepest_state = PWRDM_POWER_RET;
+        u32 core_deepest_state = PWRDM_POWER_RET;
+
+        if (enable_off_mode) {
+                mpu_deepest_state = PWRDM_POWER_OFF;
+                /*
+                 * Erratum i583: valable for ES rev < Es1.2 on 3630.
+                 * CORE OFF mode is not supported in a stable form, restrict
+                 * instead the CORE state to RET.
+                 */
+                if (!IS_PM34XX_ERRATUM(PM_SDRC_WAKEUP_ERRATUM_i583))
+                        core_deepest_state = PWRDM_POWER_OFF;
+        }
 
         /* Check if current state is valid */
-        if (cx->valid) {
+        if ((cx->valid) &&
+            (cx->mpu_state >= mpu_deepest_state) &&
+            (cx->core_state >= core_deepest_state)) {
                 return curr;
         } else {
                 int idx = OMAP3_NUM_STATES - 1;
@@ -176,7 +194,9 @@ static struct cpuidle_state *next_valid_state(struct cpuidle_device *dev,
                 idx--;
                 for (; idx >= 0; idx--) {
                         cx = cpuidle_get_statedata(&dev->states[idx]);
-                        if (cx->valid) {
+                        if ((cx->valid) &&
+                            (cx->mpu_state >= mpu_deepest_state) &&
+                            (cx->core_state >= core_deepest_state)) {
                                 next = &dev->states[idx];
                                 break;
                         }
@@ -259,31 +279,6 @@ select_state:
 
 DEFINE_PER_CPU(struct cpuidle_device, omap3_idle_dev);
 
-/**
- * omap3_cpuidle_update_states() - Update the cpuidle states
- * @mpu_deepest_state:  Enable states up to and including this for mpu domain
- * @core_deepest_state: Enable states up to and including this for core domain
- *
- * This goes through the list of states available and enables and disables the
- * validity of C states based on deepest state that can be achieved for the
- * variable domain
- */
-void omap3_cpuidle_update_states(u32 mpu_deepest_state, u32 core_deepest_state)
-{
-        int i;
-
-        for (i = 0; i < OMAP3_NUM_STATES; i++) {
-                struct omap3_idle_statedata *cx = &omap3_idle_data[i];
-
-                if ((cx->mpu_state >= mpu_deepest_state) &&
-                    (cx->core_state >= core_deepest_state)) {
-                        cx->valid = 1;
-                } else {
-                        cx->valid = 0;
-                }
-        }
-}
-
 void omap3_pm_init_cpuidle(struct cpuidle_params *cpuidle_board_params)
 {
         int i;
@@ -393,11 +388,6 @@ int __init omap3_idle_init(void)
         cx->mpu_state = PWRDM_POWER_OFF;
         cx->core_state = PWRDM_POWER_OFF;
 
-        if (enable_off_mode)
-                omap3_cpuidle_update_states(PWRDM_POWER_OFF, PWRDM_POWER_OFF);
-        else
-                omap3_cpuidle_update_states(PWRDM_POWER_RET, PWRDM_POWER_RET);
-
         dev->state_count = OMAP3_NUM_STATES;
         if (cpuidle_register_device(dev)) {
                 printk(KERN_ERR "%s: CPUidle register device failed\n",