mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-28 10:17:47 +07:00
dfea953ae2
According to hardware design, mem bit must be clear before entering DSM mode, as ARM core will be power gated in DSM mode. Signed-off-by: Anson Huang <b20788@freescale.com> Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
78 lines
1.7 KiB
C
78 lines
1.7 KiB
C
/*
|
|
* Copyright (C) 2012 Freescale Semiconductor, Inc.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/cpuidle.h>
|
|
#include <linux/module.h>
|
|
#include <asm/cpuidle.h>
|
|
#include <asm/proc-fns.h>
|
|
|
|
#include "common.h"
|
|
#include "cpuidle.h"
|
|
#include "hardware.h"
|
|
|
|
static atomic_t master = ATOMIC_INIT(0);
|
|
static DEFINE_SPINLOCK(master_lock);
|
|
|
|
static int imx6q_enter_wait(struct cpuidle_device *dev,
|
|
struct cpuidle_driver *drv, int index)
|
|
{
|
|
if (atomic_inc_return(&master) == num_online_cpus()) {
|
|
/*
|
|
* With this lock, we prevent other cpu to exit and enter
|
|
* this function again and become the master.
|
|
*/
|
|
if (!spin_trylock(&master_lock))
|
|
goto idle;
|
|
imx6q_set_lpm(WAIT_UNCLOCKED);
|
|
cpu_do_idle();
|
|
imx6q_set_lpm(WAIT_CLOCKED);
|
|
spin_unlock(&master_lock);
|
|
goto done;
|
|
}
|
|
|
|
idle:
|
|
cpu_do_idle();
|
|
done:
|
|
atomic_dec(&master);
|
|
|
|
return index;
|
|
}
|
|
|
|
static struct cpuidle_driver imx6q_cpuidle_driver = {
|
|
.name = "imx6q_cpuidle",
|
|
.owner = THIS_MODULE,
|
|
.states = {
|
|
/* WFI */
|
|
ARM_CPUIDLE_WFI_STATE,
|
|
/* WAIT */
|
|
{
|
|
.exit_latency = 50,
|
|
.target_residency = 75,
|
|
.flags = CPUIDLE_FLAG_TIME_VALID |
|
|
CPUIDLE_FLAG_TIMER_STOP,
|
|
.enter = imx6q_enter_wait,
|
|
.name = "WAIT",
|
|
.desc = "Clock off",
|
|
},
|
|
},
|
|
.state_count = 2,
|
|
.safe_state_index = 0,
|
|
};
|
|
|
|
int __init imx6q_cpuidle_init(void)
|
|
{
|
|
/* Need to enable SCU standby for entering WAIT modes */
|
|
if (!cpu_is_imx6sx())
|
|
imx_scu_standby_enable();
|
|
|
|
/* Set INT_MEM_CLK_LPM bit to get a reliable WAIT mode support */
|
|
imx6q_set_int_mem_clk_lpm(true);
|
|
|
|
return cpuidle_register(&imx6q_cpuidle_driver, NULL);
|
|
}
|