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OMAP3: PM: CPUidle: Add new lower-latency C1 state
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This patch introduces a new C state which allows MPU to go to WFI but keeps
the core domain active. This offers a much better wakeup latency (3us vs
10s of us for the current C1) at the cost of a higher power consumption.

Signed-off-by: Peter 'p2' De Schrijver <peter.de-schrijver@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
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Peter 'p2' De Schrijver authored and Kevin Hilman committed Nov 11, 2009
1 parent 0343371 commit 06d8f06
Showing 1 changed file with 81 additions and 44 deletions.
125 changes: 81 additions & 44 deletions arch/arm/mach-omap2/cpuidle34xx.c
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Original file line number Diff line number Diff line change
Expand Up @@ -25,22 +25,24 @@
#include <linux/cpuidle.h>

#include <plat/prcm.h>
#include <plat/powerdomain.h>
#include <plat/irqs.h>
#include <plat/powerdomain.h>
#include <plat/clockdomain.h>
#include <plat/control.h>
#include <plat/serial.h>

#include "pm.h"

#ifdef CONFIG_CPU_IDLE

#define OMAP3_MAX_STATES 7
#define OMAP3_MAX_STATES 8
#define OMAP3_STATE_C1 1 /* C1 - MPU WFI + Core active */
#define OMAP3_STATE_C2 2 /* C2 - MPU CSWR + Core active */
#define OMAP3_STATE_C3 3 /* C3 - MPU OFF + Core active */
#define OMAP3_STATE_C4 4 /* C4 - MPU RET + Core RET */
#define OMAP3_STATE_C5 5 /* C5 - MPU OFF + Core RET */
#define OMAP3_STATE_C6 6 /* C6 - MPU OFF + Core OFF */
#define OMAP3_STATE_C2 2 /* C2 - MPU WFI + Core inactive */
#define OMAP3_STATE_C3 3 /* C3 - MPU CSWR + Core inactive */
#define OMAP3_STATE_C4 4 /* C4 - MPU OFF + Core iactive */
#define OMAP3_STATE_C5 5 /* C5 - MPU RET + Core RET */
#define OMAP3_STATE_C6 6 /* C6 - MPU OFF + Core RET */
#define OMAP3_STATE_C7 7 /* C7 - MPU OFF + Core OFF */

struct omap3_processor_cx {
u8 valid;
Expand All @@ -64,6 +66,20 @@ static int omap3_idle_bm_check(void)
return 0;
}

static int _cpuidle_allow_idle(struct powerdomain *pwrdm,
struct clockdomain *clkdm)
{
omap2_clkdm_allow_idle(clkdm);
return 0;
}

static int _cpuidle_deny_idle(struct powerdomain *pwrdm,
struct clockdomain *clkdm)
{
omap2_clkdm_deny_idle(clkdm);
return 0;
}

/**
* omap3_enter_idle - Programs OMAP3 to enter the specified state
* @dev: cpuidle device
Expand Down Expand Up @@ -100,9 +116,19 @@ static int omap3_enter_idle(struct cpuidle_device *dev,
if (omap_irq_pending())
goto return_sleep_time;

if (cx->type == OMAP3_STATE_C1) {
pwrdm_for_each_clkdm(mpu_pd, _cpuidle_deny_idle);
pwrdm_for_each_clkdm(core_pd, _cpuidle_deny_idle);
}

/* Execute ARM wfi */
omap_sram_idle();

if (cx->type == OMAP3_STATE_C1) {
pwrdm_for_each_clkdm(mpu_pd, _cpuidle_allow_idle);
pwrdm_for_each_clkdm(core_pd, _cpuidle_allow_idle);
}

return_sleep_time:
getnstimeofday(&ts_postidle);
ts_idle = timespec_sub(ts_postidle, ts_preidle);
Expand Down Expand Up @@ -141,79 +167,90 @@ DEFINE_PER_CPU(struct cpuidle_device, omap3_idle_dev);
/* omap3_init_power_states - Initialises the OMAP3 specific C states.
*
* Below is the desciption of each C state.
* C1 . MPU WFI + Core active
* C2 . MPU CSWR + Core active
* C3 . MPU OFF + Core active
* C4 . MPU CSWR + Core CSWR
* C5 . MPU OFF + Core CSWR
* C6 . MPU OFF + Core OFF
* C1 . MPU WFI + Core active
* C2 . MPU WFI + Core inactive
* C3 . MPU CSWR + Core inactive
* C4 . MPU OFF + Core inactive
* C5 . MPU CSWR + Core CSWR
* C6 . MPU OFF + Core CSWR
* C7 . MPU OFF + Core OFF
*/
void omap_init_power_states(void)
{
/* C1 . MPU WFI + Core active */
omap3_power_states[OMAP3_STATE_C1].valid = 1;
omap3_power_states[OMAP3_STATE_C1].type = OMAP3_STATE_C1;
omap3_power_states[OMAP3_STATE_C1].sleep_latency = 10;
omap3_power_states[OMAP3_STATE_C1].wakeup_latency = 10;
omap3_power_states[OMAP3_STATE_C1].threshold = 30;
omap3_power_states[OMAP3_STATE_C1].sleep_latency = 2;
omap3_power_states[OMAP3_STATE_C1].wakeup_latency = 2;
omap3_power_states[OMAP3_STATE_C1].threshold = 5;
omap3_power_states[OMAP3_STATE_C1].mpu_state = PWRDM_POWER_ON;
omap3_power_states[OMAP3_STATE_C1].core_state = PWRDM_POWER_ON;
omap3_power_states[OMAP3_STATE_C1].flags = CPUIDLE_FLAG_TIME_VALID;

/* C2 . MPU CSWR + Core active */
/* C2 . MPU WFI + Core inactive */
omap3_power_states[OMAP3_STATE_C2].valid = 1;
omap3_power_states[OMAP3_STATE_C2].type = OMAP3_STATE_C2;
omap3_power_states[OMAP3_STATE_C2].sleep_latency = 50;
omap3_power_states[OMAP3_STATE_C2].wakeup_latency = 50;
omap3_power_states[OMAP3_STATE_C2].threshold = 300;
omap3_power_states[OMAP3_STATE_C2].mpu_state = PWRDM_POWER_RET;
omap3_power_states[OMAP3_STATE_C2].sleep_latency = 10;
omap3_power_states[OMAP3_STATE_C2].wakeup_latency = 10;
omap3_power_states[OMAP3_STATE_C2].threshold = 30;
omap3_power_states[OMAP3_STATE_C2].mpu_state = PWRDM_POWER_ON;
omap3_power_states[OMAP3_STATE_C2].core_state = PWRDM_POWER_ON;
omap3_power_states[OMAP3_STATE_C2].flags = CPUIDLE_FLAG_TIME_VALID |
CPUIDLE_FLAG_CHECK_BM;
omap3_power_states[OMAP3_STATE_C2].flags = CPUIDLE_FLAG_TIME_VALID;

/* C3 . MPU OFF + Core active */
/* C3 . MPU CSWR + Core inactive */
omap3_power_states[OMAP3_STATE_C3].valid = 1;
omap3_power_states[OMAP3_STATE_C3].type = OMAP3_STATE_C3;
omap3_power_states[OMAP3_STATE_C3].sleep_latency = 1500;
omap3_power_states[OMAP3_STATE_C3].wakeup_latency = 1800;
omap3_power_states[OMAP3_STATE_C3].threshold = 4000;
omap3_power_states[OMAP3_STATE_C3].mpu_state = PWRDM_POWER_OFF;
omap3_power_states[OMAP3_STATE_C3].sleep_latency = 50;
omap3_power_states[OMAP3_STATE_C3].wakeup_latency = 50;
omap3_power_states[OMAP3_STATE_C3].threshold = 300;
omap3_power_states[OMAP3_STATE_C3].mpu_state = PWRDM_POWER_RET;
omap3_power_states[OMAP3_STATE_C3].core_state = PWRDM_POWER_ON;
omap3_power_states[OMAP3_STATE_C3].flags = CPUIDLE_FLAG_TIME_VALID |
CPUIDLE_FLAG_CHECK_BM;

/* C4 . MPU CSWR + Core CSWR*/
/* C4 . MPU OFF + Core inactive */
omap3_power_states[OMAP3_STATE_C4].valid = 1;
omap3_power_states[OMAP3_STATE_C4].type = OMAP3_STATE_C4;
omap3_power_states[OMAP3_STATE_C4].sleep_latency = 2500;
omap3_power_states[OMAP3_STATE_C4].wakeup_latency = 7500;
omap3_power_states[OMAP3_STATE_C4].threshold = 12000;
omap3_power_states[OMAP3_STATE_C4].mpu_state = PWRDM_POWER_RET;
omap3_power_states[OMAP3_STATE_C4].core_state = PWRDM_POWER_RET;
omap3_power_states[OMAP3_STATE_C4].sleep_latency = 1500;
omap3_power_states[OMAP3_STATE_C4].wakeup_latency = 1800;
omap3_power_states[OMAP3_STATE_C4].threshold = 4000;
omap3_power_states[OMAP3_STATE_C4].mpu_state = PWRDM_POWER_OFF;
omap3_power_states[OMAP3_STATE_C4].core_state = PWRDM_POWER_ON;
omap3_power_states[OMAP3_STATE_C4].flags = CPUIDLE_FLAG_TIME_VALID |
CPUIDLE_FLAG_CHECK_BM;

/* C5 . MPU OFF + Core CSWR */
/* C5 . MPU CSWR + Core CSWR*/
omap3_power_states[OMAP3_STATE_C5].valid = 1;
omap3_power_states[OMAP3_STATE_C5].type = OMAP3_STATE_C5;
omap3_power_states[OMAP3_STATE_C5].sleep_latency = 3000;
omap3_power_states[OMAP3_STATE_C5].wakeup_latency = 8500;
omap3_power_states[OMAP3_STATE_C5].threshold = 15000;
omap3_power_states[OMAP3_STATE_C5].mpu_state = PWRDM_POWER_OFF;
omap3_power_states[OMAP3_STATE_C5].sleep_latency = 2500;
omap3_power_states[OMAP3_STATE_C5].wakeup_latency = 7500;
omap3_power_states[OMAP3_STATE_C5].threshold = 12000;
omap3_power_states[OMAP3_STATE_C5].mpu_state = PWRDM_POWER_RET;
omap3_power_states[OMAP3_STATE_C5].core_state = PWRDM_POWER_RET;
omap3_power_states[OMAP3_STATE_C5].flags = CPUIDLE_FLAG_TIME_VALID |
CPUIDLE_FLAG_CHECK_BM;

/* C6 . MPU OFF + Core OFF */
/* C6 . MPU OFF + Core CSWR */
omap3_power_states[OMAP3_STATE_C6].valid = 1;
omap3_power_states[OMAP3_STATE_C6].type = OMAP3_STATE_C6;
omap3_power_states[OMAP3_STATE_C6].sleep_latency = 10000;
omap3_power_states[OMAP3_STATE_C6].wakeup_latency = 30000;
omap3_power_states[OMAP3_STATE_C6].threshold = 300000;
omap3_power_states[OMAP3_STATE_C6].sleep_latency = 3000;
omap3_power_states[OMAP3_STATE_C6].wakeup_latency = 8500;
omap3_power_states[OMAP3_STATE_C6].threshold = 15000;
omap3_power_states[OMAP3_STATE_C6].mpu_state = PWRDM_POWER_OFF;
omap3_power_states[OMAP3_STATE_C6].core_state = PWRDM_POWER_OFF;
omap3_power_states[OMAP3_STATE_C6].core_state = PWRDM_POWER_RET;
omap3_power_states[OMAP3_STATE_C6].flags = CPUIDLE_FLAG_TIME_VALID |
CPUIDLE_FLAG_CHECK_BM;

/* C7 . MPU OFF + Core OFF */
omap3_power_states[OMAP3_STATE_C7].valid = 1;
omap3_power_states[OMAP3_STATE_C7].type = OMAP3_STATE_C7;
omap3_power_states[OMAP3_STATE_C7].sleep_latency = 10000;
omap3_power_states[OMAP3_STATE_C7].wakeup_latency = 30000;
omap3_power_states[OMAP3_STATE_C7].threshold = 300000;
omap3_power_states[OMAP3_STATE_C7].mpu_state = PWRDM_POWER_OFF;
omap3_power_states[OMAP3_STATE_C7].core_state = PWRDM_POWER_OFF;
omap3_power_states[OMAP3_STATE_C7].flags = CPUIDLE_FLAG_TIME_VALID |
CPUIDLE_FLAG_CHECK_BM;
}

struct cpuidle_driver omap3_idle_driver = {
Expand Down

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