https://github.com/torvalds/linux
Tip revision: c3f38fa61af77b49866b006939479069cd451173 authored by Linus Torvalds on 02 June 2024, 22:44:56 UTC
Linux 6.10-rc2
Linux 6.10-rc2
Tip revision: c3f38fa
pm.c
// 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_core() - 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);
}