linux_dsm_epyc7002/arch/sh/kernel/cpu/shmobile/pm.c
Magnus Damm 02bf89347c sh: Keep track of allowed sleep modes
Add code to keep track of supported sleep modes. This to
only export cpuidle modes that are backed by board support
code. Also, do not allow suspend-to-ram if sdram board code
is missing.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-10-30 14:37:42 +09:00

138 lines
3.6 KiB
C

/*
* arch/sh/kernel/cpu/shmobile/pm.c
*
* Power management support code for SuperH Mobile
*
* Copyright (C) 2009 Magnus Damm
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/suspend.h>
#include <asm/suspend.h>
#include <asm/uaccess.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)
/*
* The following modes are not there yet:
*
* R-standby mode is unsupported, but will be added in the future
* U-standby mode is low priority since it needs bootloader hacks
*/
#define ILRAM_BASE 0xe5200000
void sh_mobile_call_standby(unsigned long mode)
{
void *onchip_mem = (void *)ILRAM_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);
/* Let assembly snippet in on-chip memory handle the rest */
standby_onchip_mem(mode, ILRAM_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 *)ILRAM_BASE;
void *vp;
struct sh_sleep_data *sdp;
int n;
/* part 0: data area */
sdp = onchip_mem;
sdp->addr.stbcr = 0xa4150020; /* STBCR */
vp = sdp + 1;
/* part 1: common code to enter sleep mode */
n = &sh_mobile_sleep_enter_end - &sh_mobile_sleep_enter_start;
memcpy(vp, &sh_mobile_sleep_enter_start, n);
vp += roundup(n, 4);
/* part 2: board specific code to enter self-refresh mode */
n = pre_end - pre_start;
memcpy(vp, pre_start, n);
sdp->sf_pre = (unsigned long)vp;
vp += roundup(n, 4);
/* part 3: board specific code to resume from self-refresh mode */
n = post_end - post_start;
memcpy(vp, post_start, n);
sdp->sf_post = (unsigned long)vp;
vp += roundup(n, 4);
/* part 4: common code to resume from sleep mode */
WARN_ON(vp > (onchip_mem + 0x600));
vp = onchip_mem + 0x600; /* located at interrupt vector */
n = &sh_mobile_sleep_resume_end - &sh_mobile_sleep_resume_start;
memcpy(vp, &sh_mobile_sleep_resume_start, n);
sh_mobile_sleep_supported |= flags;
}
static int sh_pm_enter(suspend_state_t state)
{
if (!(sh_mobile_sleep_supported & SUSP_MODE_STANDBY_SF))
return -ENXIO;
local_irq_disable();
set_bl_bit();
sh_mobile_call_standby(SUSP_MODE_STANDBY_SF);
local_irq_disable();
clear_bl_bit();
return 0;
}
static struct platform_suspend_ops sh_pm_ops = {
.enter = sh_pm_enter,
.valid = suspend_valid_only_mem,
};
static int __init sh_pm_init(void)
{
suspend_set_ops(&sh_pm_ops);
sh_mobile_setup_cpuidle();
return 0;
}
late_initcall(sh_pm_init);