diff options
Diffstat (limited to 'kernel/arch/arm/mach-davinci/pm.c')
-rw-r--r-- | kernel/arch/arm/mach-davinci/pm.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-davinci/pm.c b/kernel/arch/arm/mach-davinci/pm.c new file mode 100644 index 000000000..07e23ba61 --- /dev/null +++ b/kernel/arch/arm/mach-davinci/pm.c @@ -0,0 +1,158 @@ +/* + * 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 <asm/io.h> + +#include <mach/common.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", + }, + .remove = __exit_p(davinci_pm_remove), +}; + +int __init davinci_pm_init(void) +{ + return platform_driver_probe(&davinci_pm_driver, davinci_pm_probe); +} |