arch/sh/kernel/cpu/shmobile/pm.c

Source file repositories/reference/linux-study-clean/arch/sh/kernel/cpu/shmobile/pm.c

File Facts

System
Linux kernel
Corpus path
arch/sh/kernel/cpu/shmobile/pm.c
Extension
.c
Size
4275 bytes
Lines
154
Domain
Architecture Layer
Bucket
arch/sh
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
/*
 * arch/sh/kernel/cpu/shmobile/pm.c
 *
 * Power management support code for SuperH Mobile
 *
 *  Copyright (C) 2009 Magnus Damm
 */
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/suspend.h>
#include <asm/suspend.h>
#include <linux/uaccess.h>
#include <asm/cacheflush.h>
#include <asm/bl_bit.h>

/*
 * Notifier lists for pre/post sleep notification
 */
ATOMIC_NOTIFIER_HEAD(sh_mobile_pre_sleep_notifier_list);
ATOMIC_NOTIFIER_HEAD(sh_mobile_post_sleep_notifier_list);

/*
 * Sleep modes available on SuperH Mobile:
 *
 * Sleep mode is just plain "sleep" instruction
 * Sleep Self-Refresh mode is above plus RAM put in Self-Refresh
 * Standby Self-Refresh mode is above plus stopped clocks
 */
#define SUSP_MODE_SLEEP		(SUSP_SH_SLEEP)
#define SUSP_MODE_SLEEP_SF	(SUSP_SH_SLEEP | SUSP_SH_SF)
#define SUSP_MODE_STANDBY_SF	(SUSP_SH_STANDBY | SUSP_SH_SF)
#define SUSP_MODE_RSTANDBY_SF \
	(SUSP_SH_RSTANDBY | SUSP_SH_MMU | SUSP_SH_REGS | SUSP_SH_SF)
 /*
  * U-standby mode is unsupported since it needs bootloader hacks
  */

#ifdef CONFIG_CPU_SUBTYPE_SH7724
#define RAM_BASE 0xfd800000 /* RSMEM */
#else
#define RAM_BASE 0xe5200000 /* ILRAM */
#endif

void sh_mobile_call_standby(unsigned long mode)
{
	void *onchip_mem = (void *)RAM_BASE;
	struct sh_sleep_data *sdp = onchip_mem;
	void (*standby_onchip_mem)(unsigned long, unsigned long);

	/* code located directly after data structure */
	standby_onchip_mem = (void *)(sdp + 1);

	atomic_notifier_call_chain(&sh_mobile_pre_sleep_notifier_list,
				   mode, NULL);

	/* flush the caches if MMU flag is set */
	if (mode & SUSP_SH_MMU)
		flush_cache_all();

	/* Let assembly snippet in on-chip memory handle the rest */
	standby_onchip_mem(mode, RAM_BASE);

	atomic_notifier_call_chain(&sh_mobile_post_sleep_notifier_list,
				   mode, NULL);
}

extern char sh_mobile_sleep_enter_start;
extern char sh_mobile_sleep_enter_end;

extern char sh_mobile_sleep_resume_start;
extern char sh_mobile_sleep_resume_end;

unsigned long sh_mobile_sleep_supported = SUSP_SH_SLEEP;

void sh_mobile_register_self_refresh(unsigned long flags,
				     void *pre_start, void *pre_end,
				     void *post_start, void *post_end)
{
	void *onchip_mem = (void *)RAM_BASE;
	void *vp;
	struct sh_sleep_data *sdp;
	int n;

	/* part 0: data area */
	sdp = onchip_mem;
	sdp->addr.stbcr = 0xa4150020; /* STBCR */
	sdp->addr.bar = 0xa4150040; /* BAR */
	sdp->addr.pteh = 0xff000000; /* PTEH */

Annotation

Implementation Notes