diff options
Diffstat (limited to 'arch/arm/mach-s5pv210/pm.c')
| -rw-r--r-- | arch/arm/mach-s5pv210/pm.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/arch/arm/mach-s5pv210/pm.c b/arch/arm/mach-s5pv210/pm.c new file mode 100644 index 000000000..d59c094cd --- /dev/null +++ b/arch/arm/mach-s5pv210/pm.c @@ -0,0 +1,214 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Copyright (c) 2010-2014 Samsung Electronics Co., Ltd. +// http://www.samsung.com +// +// S5PV210 - Power Management support +// +// Based on arch/arm/mach-s3c2410/pm.c +// Copyright (c) 2006 Simtec Electronics +// Ben Dooks <ben@simtec.co.uk> + +#include <linux/init.h> +#include <linux/suspend.h> +#include <linux/syscore_ops.h> +#include <linux/io.h> +#include <linux/soc/samsung/s3c-pm.h> + +#include <asm/cacheflush.h> +#include <asm/suspend.h> + +#include "common.h" +#include "regs-clock.h" + +/* helper functions to save and restore register state */ +struct sleep_save { + void __iomem *reg; + unsigned long val; +}; + +#define SAVE_ITEM(x) \ + { .reg = (x) } + +/** + * s3c_pm_do_save() - save a set of registers for restoration on resume. + * @ptr: Pointer to an array of registers. + * @count: Size of the ptr array. + * + * Run through the list of registers given, saving their contents in the + * array for later restoration when we wakeup. + */ +static void s3c_pm_do_save(struct sleep_save *ptr, int count) +{ + for (; count > 0; count--, ptr++) { + ptr->val = readl_relaxed(ptr->reg); + S3C_PMDBG("saved %p value %08lx\n", ptr->reg, ptr->val); + } +} + +/** + * s3c_pm_do_restore() - restore register values from the save list. + * @ptr: Pointer to an array of registers. + * @count: Size of the ptr array. + * + * Restore the register values saved from s3c_pm_do_save(). + * + * WARNING: Do not put any debug in here that may effect memory or use + * peripherals, as things may be changing! +*/ + +static void s3c_pm_do_restore_core(const struct sleep_save *ptr, int count) +{ + for (; count > 0; count--, ptr++) + writel_relaxed(ptr->val, ptr->reg); +} + +static struct sleep_save s5pv210_core_save[] = { + /* Clock ETC */ + SAVE_ITEM(S5P_MDNIE_SEL), +}; + +/* + * VIC wake-up support (TODO) + */ +static u32 s5pv210_irqwake_intmask = 0xffffffff; + +static u32 s5pv210_read_eint_wakeup_mask(void) +{ + return __raw_readl(S5P_EINT_WAKEUP_MASK); +} + +/* + * Suspend helpers. + */ +static int s5pv210_cpu_suspend(unsigned long arg) +{ + unsigned long tmp; + + /* issue the standby signal into the pm unit. Note, we + * issue a write-buffer drain just in case */ + + tmp = 0; + + asm("b 1f\n\t" + ".align 5\n\t" + "1:\n\t" + "mcr p15, 0, %0, c7, c10, 5\n\t" + "mcr p15, 0, %0, c7, c10, 4\n\t" + "wfi" : : "r" (tmp)); + + pr_info("Failed to suspend the system\n"); + return 1; /* Aborting suspend */ +} + +static void s5pv210_pm_prepare(void) +{ + unsigned int tmp; + + /* + * Set wake-up mask registers + * S5P_EINT_WAKEUP_MASK is set by pinctrl driver in late suspend. + */ + __raw_writel(s5pv210_irqwake_intmask, S5P_WAKEUP_MASK); + + /* ensure at least INFORM0 has the resume address */ + __raw_writel(__pa_symbol(s5pv210_cpu_resume), S5P_INFORM0); + + tmp = __raw_readl(S5P_SLEEP_CFG); + tmp &= ~(S5P_SLEEP_CFG_OSC_EN | S5P_SLEEP_CFG_USBOSC_EN); + __raw_writel(tmp, S5P_SLEEP_CFG); + + /* WFI for SLEEP mode configuration by SYSCON */ + tmp = __raw_readl(S5P_PWR_CFG); + tmp &= S5P_CFG_WFI_CLEAN; + tmp |= S5P_CFG_WFI_SLEEP; + __raw_writel(tmp, S5P_PWR_CFG); + + /* SYSCON interrupt handling disable */ + tmp = __raw_readl(S5P_OTHERS); + tmp |= S5P_OTHER_SYSC_INTOFF; + __raw_writel(tmp, S5P_OTHERS); + + s3c_pm_do_save(s5pv210_core_save, ARRAY_SIZE(s5pv210_core_save)); +} + +/* + * Suspend operations. + */ +static int s5pv210_suspend_enter(suspend_state_t state) +{ + u32 eint_wakeup_mask = s5pv210_read_eint_wakeup_mask(); + int ret; + + S3C_PMDBG("%s: suspending the system...\n", __func__); + + S3C_PMDBG("%s: wakeup masks: %08x,%08x\n", __func__, + s5pv210_irqwake_intmask, eint_wakeup_mask); + + if (s5pv210_irqwake_intmask == -1U + && eint_wakeup_mask == -1U) { + pr_err("%s: No wake-up sources!\n", __func__); + pr_err("%s: Aborting sleep\n", __func__); + return -EINVAL; + } + + s3c_pm_save_uarts(false); + s5pv210_pm_prepare(); + flush_cache_all(); + s3c_pm_check_store(); + + ret = cpu_suspend(0, s5pv210_cpu_suspend); + if (ret) + return ret; + + s3c_pm_restore_uarts(false); + + S3C_PMDBG("%s: wakeup stat: %08x\n", __func__, + __raw_readl(S5P_WAKEUP_STAT)); + + s3c_pm_check_restore(); + + S3C_PMDBG("%s: resuming the system...\n", __func__); + + return 0; +} + +static int s5pv210_suspend_prepare(void) +{ + s3c_pm_check_prepare(); + + return 0; +} + +static void s5pv210_suspend_finish(void) +{ + s3c_pm_check_cleanup(); +} + +static const struct platform_suspend_ops s5pv210_suspend_ops = { + .enter = s5pv210_suspend_enter, + .prepare = s5pv210_suspend_prepare, + .finish = s5pv210_suspend_finish, + .valid = suspend_valid_only_mem, +}; + +/* + * Syscore operations used to delay restore of certain registers. + */ +static void s5pv210_pm_resume(void) +{ + s3c_pm_do_restore_core(s5pv210_core_save, ARRAY_SIZE(s5pv210_core_save)); +} + +static struct syscore_ops s5pv210_pm_syscore_ops = { + .resume = s5pv210_pm_resume, +}; + +/* + * Initialization entry point. + */ +void __init s5pv210_pm_init(void) +{ + register_syscore_ops(&s5pv210_pm_syscore_ops); + suspend_set_ops(&s5pv210_suspend_ops); +} |