linux/arch/arm/mach-davinci/pm.c

159 lines
3.8 KiB
C

/*
* DaVinci Power Management Routines
*
* Copyright (C) 2009 Texas Instruments, Inc. http://www.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/platform_device.h>
#include <linux/clk.h>
#include <linux/spinlock.h>
#include <asm/cacheflush.h>
#include <asm/delay.h>
#include <mach/da8xx.h>
#include <mach/sram.h>
#include <mach/pm.h>
#include "clock.h"
#define DEEPSLEEP_SLEEPCOUNT_MASK 0xFFFF
static void (*davinci_sram_suspend) (struct davinci_pm_config *);
static struct davinci_pm_config *pdata;
static void davinci_sram_push(void *dest, void *src, unsigned int size)
{
memcpy(dest, src, size);
flush_icache_range((unsigned long)dest, (unsigned long)(dest + size));
}
static void davinci_pm_suspend(void)
{
unsigned val;
if (pdata->cpupll_reg_base != pdata->ddrpll_reg_base) {
/* Switch CPU PLL to bypass mode */
val = __raw_readl(pdata->cpupll_reg_base + PLLCTL);
val &= ~(PLLCTL_PLLENSRC | PLLCTL_PLLEN);
__raw_writel(val, pdata->cpupll_reg_base + PLLCTL);
udelay(PLL_BYPASS_TIME);
/* Powerdown CPU PLL */
val = __raw_readl(pdata->cpupll_reg_base + PLLCTL);
val |= PLLCTL_PLLPWRDN;
__raw_writel(val, pdata->cpupll_reg_base + PLLCTL);
}
/* Configure sleep count in deep sleep register */
val = __raw_readl(pdata->deepsleep_reg);
val &= ~DEEPSLEEP_SLEEPCOUNT_MASK,
val |= pdata->sleepcount;
__raw_writel(val, pdata->deepsleep_reg);
/* System goes to sleep in this call */
davinci_sram_suspend(pdata);
if (pdata->cpupll_reg_base != pdata->ddrpll_reg_base) {
/* put CPU PLL in reset */
val = __raw_readl(pdata->cpupll_reg_base + PLLCTL);
val &= ~PLLCTL_PLLRST;
__raw_writel(val, pdata->cpupll_reg_base + PLLCTL);
/* put CPU PLL in power down */
val = __raw_readl(pdata->cpupll_reg_base + PLLCTL);
val &= ~PLLCTL_PLLPWRDN;
__raw_writel(val, pdata->cpupll_reg_base + PLLCTL);
/* wait for CPU PLL reset */
udelay(PLL_RESET_TIME);
/* bring CPU PLL out of reset */
val = __raw_readl(pdata->cpupll_reg_base + PLLCTL);
val |= PLLCTL_PLLRST;
__raw_writel(val, pdata->cpupll_reg_base + PLLCTL);
/* Wait for CPU PLL to lock */
udelay(PLL_LOCK_TIME);
/* Remove CPU PLL from bypass mode */
val = __raw_readl(pdata->cpupll_reg_base + PLLCTL);
val &= ~PLLCTL_PLLENSRC;
val |= PLLCTL_PLLEN;
__raw_writel(val, pdata->cpupll_reg_base + PLLCTL);
}
}
static int davinci_pm_enter(suspend_state_t state)
{
int ret = 0;
switch (state) {
case PM_SUSPEND_STANDBY:
case PM_SUSPEND_MEM:
davinci_pm_suspend();
break;
default:
ret = -EINVAL;
}
return ret;
}
static const struct platform_suspend_ops davinci_pm_ops = {
.enter = davinci_pm_enter,
.valid = suspend_valid_only_mem,
};
static int __init davinci_pm_probe(struct platform_device *pdev)
{
pdata = pdev->dev.platform_data;
if (!pdata) {
dev_err(&pdev->dev, "cannot get platform data\n");
return -ENOENT;
}
davinci_sram_suspend = sram_alloc(davinci_cpu_suspend_sz, NULL);
if (!davinci_sram_suspend) {
dev_err(&pdev->dev, "cannot allocate SRAM memory\n");
return -ENOMEM;
}
davinci_sram_push(davinci_sram_suspend, davinci_cpu_suspend,
davinci_cpu_suspend_sz);
suspend_set_ops(&davinci_pm_ops);
return 0;
}
static int __exit davinci_pm_remove(struct platform_device *pdev)
{
sram_free(davinci_sram_suspend, davinci_cpu_suspend_sz);
return 0;
}
static struct platform_driver davinci_pm_driver = {
.driver = {
.name = "pm-davinci",
.owner = THIS_MODULE,
},
.remove = __exit_p(davinci_pm_remove),
};
static int __init davinci_pm_init(void)
{
return platform_driver_probe(&davinci_pm_driver, davinci_pm_probe);
}
late_initcall(davinci_pm_init);