arch/arm/mach-s3c/pm.c

Source file repositories/reference/linux-study-clean/arch/arm/mach-s3c/pm.c

File Facts

System
Linux kernel
Corpus path
arch/arm/mach-s3c/pm.c
Extension
.c
Size
4175 bytes
Lines
197
Domain
Architecture Layer
Bucket
arch/arm
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
//
// Copyright 2008 Openmoko, Inc.
// Copyright 2004-2008 Simtec Electronics
//	Ben Dooks <ben@simtec.co.uk>
//	http://armlinux.simtec.co.uk/
//
// S3C common power management (suspend to ram) support.

#include <linux/init.h>
#include <linux/suspend.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/serial_s3c.h>
#include <linux/io.h>

#include <asm/cacheflush.h>
#include <asm/suspend.h>

#include "map.h"
#include "regs-clock.h"
#include "regs-irq.h"
#include "irqs.h"

#include <asm/irq.h>

#include "cpu.h"
#include "pm.h"
#include "pm-core.h"

/* for external use */

unsigned long s3c_pm_flags;

/* The IRQ ext-int code goes here, it is too small to currently bother
 * with its own file. */

unsigned long s3c_irqwake_intmask	= 0xffffffffL;
unsigned long s3c_irqwake_eintmask	= 0xffffffffL;

int s3c_irqext_wake(struct irq_data *data, unsigned int state)
{
	unsigned long bit = 1L << IRQ_EINT_BIT(data->irq);

	if (!(s3c_irqwake_eintallow & bit))
		return -ENOENT;

	printk(KERN_INFO "wake %s for irq %d\n",
	       state ? "enabled" : "disabled", data->irq);

	if (!state)
		s3c_irqwake_eintmask |= bit;
	else
		s3c_irqwake_eintmask &= ~bit;

	return 0;
}

void (*pm_cpu_prep)(void);
int (*pm_cpu_sleep)(unsigned long);

#define any_allowed(mask, allow) (((mask) & (allow)) != (allow))

/* s3c_pm_enter
 *
 * central control for sleep/resume process
*/

static int s3c_pm_enter(suspend_state_t state)
{
	int ret;
	/* ensure the debug is initialised (if enabled) */
	s3c_pm_debug_init_uart();

	S3C_PMDBG("%s(%d)\n", __func__, state);

	if (pm_cpu_prep == NULL || pm_cpu_sleep == NULL) {
		printk(KERN_ERR "%s: error: no cpu sleep function\n", __func__);
		return -EINVAL;
	}

	/* check if we have anything to wake-up with... bad things seem
	 * to happen if you suspend with no wakeup (system will often
	 * require a full power-cycle)
	*/

	if (!of_have_populated_dt() &&
	    !any_allowed(s3c_irqwake_intmask, s3c_irqwake_intallow) &&
	    !any_allowed(s3c_irqwake_eintmask, s3c_irqwake_eintallow)) {

Annotation

Implementation Notes