linux_dsm_epyc7002/arch/sh/kernel/cpu/shmobile/cpuidle.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

120 lines
3.2 KiB
C

/*
* arch/sh/kernel/cpu/shmobile/cpuidle.c
*
* Cpuidle 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 <linux/cpuidle.h>
#include <asm/suspend.h>
#include <asm/uaccess.h>
#include <asm/hwblk.h>
static unsigned long cpuidle_mode[] = {
SUSP_SH_SLEEP, /* regular sleep mode */
SUSP_SH_SLEEP | SUSP_SH_SF, /* sleep mode + self refresh */
SUSP_SH_STANDBY | SUSP_SH_SF, /* software standby mode + self refresh */
};
static int cpuidle_sleep_enter(struct cpuidle_device *dev,
struct cpuidle_state *state)
{
unsigned long allowed_mode = arch_hwblk_sleep_mode();
ktime_t before, after;
int requested_state = state - &dev->states[0];
int allowed_state;
int k;
/* convert allowed mode to allowed state */
for (k = ARRAY_SIZE(cpuidle_mode) - 1; k > 0; k--)
if (cpuidle_mode[k] == allowed_mode)
break;
allowed_state = k;
/* take the following into account for sleep mode selection:
* - allowed_state: best mode allowed by hardware (clock deps)
* - requested_state: best mode allowed by software (latencies)
*/
k = min_t(int, allowed_state, requested_state);
dev->last_state = &dev->states[k];
before = ktime_get();
sh_mobile_call_standby(cpuidle_mode[k]);
after = ktime_get();
return ktime_to_ns(ktime_sub(after, before)) >> 10;
}
static struct cpuidle_device cpuidle_dev;
static struct cpuidle_driver cpuidle_driver = {
.name = "sh_idle",
.owner = THIS_MODULE,
};
void sh_mobile_setup_cpuidle(void)
{
struct cpuidle_device *dev = &cpuidle_dev;
struct cpuidle_state *state;
int i;
cpuidle_register_driver(&cpuidle_driver);
for (i = 0; i < CPUIDLE_STATE_MAX; i++) {
dev->states[i].name[0] = '\0';
dev->states[i].desc[0] = '\0';
}
i = CPUIDLE_DRIVER_STATE_START;
state = &dev->states[i++];
snprintf(state->name, CPUIDLE_NAME_LEN, "C0");
strncpy(state->desc, "SuperH Sleep Mode", CPUIDLE_DESC_LEN);
state->exit_latency = 1;
state->target_residency = 1 * 2;
state->power_usage = 3;
state->flags = 0;
state->flags |= CPUIDLE_FLAG_SHALLOW;
state->flags |= CPUIDLE_FLAG_TIME_VALID;
state->enter = cpuidle_sleep_enter;
dev->safe_state = state;
if (sh_mobile_sleep_supported & SUSP_SH_SF) {
state = &dev->states[i++];
snprintf(state->name, CPUIDLE_NAME_LEN, "C1");
strncpy(state->desc, "SuperH Sleep Mode [SF]",
CPUIDLE_DESC_LEN);
state->exit_latency = 100;
state->target_residency = 1 * 2;
state->power_usage = 1;
state->flags = 0;
state->flags |= CPUIDLE_FLAG_TIME_VALID;
state->enter = cpuidle_sleep_enter;
}
if (sh_mobile_sleep_supported & SUSP_SH_STANDBY) {
state = &dev->states[i++];
snprintf(state->name, CPUIDLE_NAME_LEN, "C2");
strncpy(state->desc, "SuperH Mobile Standby Mode [SF]",
CPUIDLE_DESC_LEN);
state->exit_latency = 2300;
state->target_residency = 1 * 2;
state->power_usage = 1;
state->flags = 0;
state->flags |= CPUIDLE_FLAG_TIME_VALID;
state->enter = cpuidle_sleep_enter;
}
dev->state_count = i;
cpuidle_register_device(dev);
}