linux_dsm_epyc7002/arch/arm/mach-omap2/pm44xx.c
Santosh Shilimkar 9827266097 ARM: OMAP4: PM: Add CPUidle support
Add OMAP4 CPUIDLE support. CPU1 is left with defualt idle and
the low power state for it is managed via cpu-hotplug.

This patch adds MPUSS low power states in cpuidle.

	C1 - CPU0 ON + CPU1 ON + MPU ON
	C2 - CPU0 OFF + CPU1 OFF + MPU CSWR
	C3 - CPU0 OFF + CPU1 OFF + MPU OSWR

OMAP4460 onwards, MPUSS power domain doesn't support OFF state any more
anymore just like CORE power domain. The deepest state supported is OSWr.
Ofcourse when MPUSS and CORE PD transitions to OSWR along with device
off mode, even the memory contemts are lost which is as good as
the PD off state.

On OMAP4 because of hardware constraints, no low power states are
targeted when both CPUs are online and in SMP mode. The low power
states are attempted only when secondary CPU gets offline to OFF
through hotplug infrastructure.

Thanks to Nicole Chalhoub <n-chalhoub@ti.com> for doing exhaustive
C-state latency profiling.

Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Vishwanath BS <vishwanath.bs@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
2011-12-08 11:29:01 -08:00

267 lines
6.6 KiB
C

/*
* OMAP4 Power Management Routines
*
* Copyright (C) 2010-2011 Texas Instruments, Inc.
* Rajendra Nayak <rnayak@ti.com>
* Santosh Shilimkar <santosh.shilimkar@ti.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/pm.h>
#include <linux/suspend.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/err.h>
#include <linux/slab.h>
#include "common.h"
#include "clockdomain.h"
#include "powerdomain.h"
#include "pm.h"
struct power_state {
struct powerdomain *pwrdm;
u32 next_state;
#ifdef CONFIG_SUSPEND
u32 saved_state;
u32 saved_logic_state;
#endif
struct list_head node;
};
static LIST_HEAD(pwrst_list);
#ifdef CONFIG_SUSPEND
static int omap4_pm_suspend(void)
{
struct power_state *pwrst;
int state, ret = 0;
u32 cpu_id = smp_processor_id();
/* Save current powerdomain state */
list_for_each_entry(pwrst, &pwrst_list, node) {
pwrst->saved_state = pwrdm_read_next_pwrst(pwrst->pwrdm);
pwrst->saved_logic_state = pwrdm_read_logic_retst(pwrst->pwrdm);
}
/* Set targeted power domain states by suspend */
list_for_each_entry(pwrst, &pwrst_list, node) {
omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
pwrdm_set_logic_retst(pwrst->pwrdm, PWRDM_POWER_OFF);
}
/*
* For MPUSS to hit power domain retention(CSWR or OSWR),
* CPU0 and CPU1 power domains need to be in OFF or DORMANT state,
* since CPU power domain CSWR is not supported by hardware
* Only master CPU follows suspend path. All other CPUs follow
* CPU hotplug path in system wide suspend. On OMAP4, CPU power
* domain CSWR is not supported by hardware.
* More details can be found in OMAP4430 TRM section 4.3.4.2.
*/
omap4_enter_lowpower(cpu_id, PWRDM_POWER_OFF);
/* Restore next powerdomain state */
list_for_each_entry(pwrst, &pwrst_list, node) {
state = pwrdm_read_prev_pwrst(pwrst->pwrdm);
if (state > pwrst->next_state) {
pr_info("Powerdomain (%s) didn't enter "
"target state %d\n",
pwrst->pwrdm->name, pwrst->next_state);
ret = -1;
}
omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state);
pwrdm_set_logic_retst(pwrst->pwrdm, pwrst->saved_logic_state);
}
if (ret)
pr_crit("Could not enter target state in pm_suspend\n");
else
pr_info("Successfully put all powerdomains to target state\n");
return 0;
}
static int omap4_pm_enter(suspend_state_t suspend_state)
{
int ret = 0;
switch (suspend_state) {
case PM_SUSPEND_STANDBY:
case PM_SUSPEND_MEM:
ret = omap4_pm_suspend();
break;
default:
ret = -EINVAL;
}
return ret;
}
static int omap4_pm_begin(suspend_state_t state)
{
disable_hlt();
return 0;
}
static void omap4_pm_end(void)
{
enable_hlt();
return;
}
static const struct platform_suspend_ops omap_pm_ops = {
.begin = omap4_pm_begin,
.end = omap4_pm_end,
.enter = omap4_pm_enter,
.valid = suspend_valid_only_mem,
};
#endif /* CONFIG_SUSPEND */
/*
* Enable hardware supervised mode for all clockdomains if it's
* supported. Initiate sleep transition for other clockdomains, if
* they are not used
*/
static int __init clkdms_setup(struct clockdomain *clkdm, void *unused)
{
if (clkdm->flags & CLKDM_CAN_ENABLE_AUTO)
clkdm_allow_idle(clkdm);
else if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP &&
atomic_read(&clkdm->usecount) == 0)
clkdm_sleep(clkdm);
return 0;
}
static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
{
struct power_state *pwrst;
if (!pwrdm->pwrsts)
return 0;
/*
* Skip CPU0 and CPU1 power domains. CPU1 is programmed
* through hotplug path and CPU0 explicitly programmed
* further down in the code path
*/
if (!strncmp(pwrdm->name, "cpu", 3))
return 0;
/*
* FIXME: Remove this check when core retention is supported
* Only MPUSS power domain is added in the list.
*/
if (strcmp(pwrdm->name, "mpu_pwrdm"))
return 0;
pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
if (!pwrst)
return -ENOMEM;
pwrst->pwrdm = pwrdm;
pwrst->next_state = PWRDM_POWER_RET;
list_add(&pwrst->node, &pwrst_list);
return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
}
/**
* omap_default_idle - OMAP4 default ilde routine.'
*
* Implements OMAP4 memory, IO ordering requirements which can't be addressed
* with default arch_idle() hook. Used by all CPUs with !CONFIG_CPUIDLE and
* by secondary CPU with CONFIG_CPUIDLE.
*/
static void omap_default_idle(void)
{
local_irq_disable();
local_fiq_disable();
omap_do_wfi();
local_fiq_enable();
local_irq_enable();
}
/**
* omap4_pm_init - Init routine for OMAP4 PM
*
* Initializes all powerdomain and clockdomain target states
* and all PRCM settings.
*/
static int __init omap4_pm_init(void)
{
int ret;
struct clockdomain *emif_clkdm, *mpuss_clkdm, *l3_1_clkdm;
struct clockdomain *ducati_clkdm, *l3_2_clkdm, *l4_per_clkdm;
if (!cpu_is_omap44xx())
return -ENODEV;
if (omap_rev() == OMAP4430_REV_ES1_0) {
WARN(1, "Power Management not supported on OMAP4430 ES1.0\n");
return -ENODEV;
}
pr_err("Power Management for TI OMAP4.\n");
ret = pwrdm_for_each(pwrdms_setup, NULL);
if (ret) {
pr_err("Failed to setup powerdomains\n");
goto err2;
}
/*
* The dynamic dependency between MPUSS -> MEMIF and
* MPUSS -> L4_PER/L3_* and DUCATI -> L3_* doesn't work as
* expected. The hardware recommendation is to enable static
* dependencies for these to avoid system lock ups or random crashes.
*/
mpuss_clkdm = clkdm_lookup("mpuss_clkdm");
emif_clkdm = clkdm_lookup("l3_emif_clkdm");
l3_1_clkdm = clkdm_lookup("l3_1_clkdm");
l3_2_clkdm = clkdm_lookup("l3_2_clkdm");
l4_per_clkdm = clkdm_lookup("l4_per_clkdm");
ducati_clkdm = clkdm_lookup("ducati_clkdm");
if ((!mpuss_clkdm) || (!emif_clkdm) || (!l3_1_clkdm) ||
(!l3_2_clkdm) || (!ducati_clkdm) || (!l4_per_clkdm))
goto err2;
ret = clkdm_add_wkdep(mpuss_clkdm, emif_clkdm);
ret |= clkdm_add_wkdep(mpuss_clkdm, l3_1_clkdm);
ret |= clkdm_add_wkdep(mpuss_clkdm, l3_2_clkdm);
ret |= clkdm_add_wkdep(mpuss_clkdm, l4_per_clkdm);
ret |= clkdm_add_wkdep(ducati_clkdm, l3_1_clkdm);
ret |= clkdm_add_wkdep(ducati_clkdm, l3_2_clkdm);
if (ret) {
pr_err("Failed to add MPUSS -> L3/EMIF/L4PER, DUCATI -> L3 "
"wakeup dependency\n");
goto err2;
}
ret = omap4_mpuss_init();
if (ret) {
pr_err("Failed to initialise OMAP4 MPUSS\n");
goto err2;
}
(void) clkdm_for_each(clkdms_setup, NULL);
#ifdef CONFIG_SUSPEND
suspend_set_ops(&omap_pm_ops);
#endif /* CONFIG_SUSPEND */
/* Overwrite the default arch_idle() */
pm_idle = omap_default_idle;
omap4_idle_init();
err2:
return ret;
}
late_initcall(omap4_pm_init);