forked from Minki/linux
18aebf116b
The core is not powered down, it is pointless to call the cpu_pm notifiers and switch to the global timer. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-and-tested-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com>
81 lines
2.1 KiB
C
81 lines
2.1 KiB
C
/*
|
|
* Copyright (C) 2012-2013 Xilinx
|
|
*
|
|
* CPU idle support for Xilinx Zynq
|
|
*
|
|
* based on arch/arm/mach-at91/cpuidle.c
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms and conditions of the GNU General Public License,
|
|
* version 2, as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope it will be useful, but WITHOUT
|
|
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
|
|
* more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along with
|
|
* this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
* The cpu idle uses wait-for-interrupt and RAM self refresh in order
|
|
* to implement two idle states -
|
|
* #1 wait-for-interrupt
|
|
* #2 wait-for-interrupt and RAM self refresh
|
|
*
|
|
* Maintainer: Michal Simek <michal.simek@xilinx.com>
|
|
*/
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/cpuidle.h>
|
|
#include <linux/platform_device.h>
|
|
#include <asm/proc-fns.h>
|
|
#include <asm/cpuidle.h>
|
|
|
|
#define ZYNQ_MAX_STATES 2
|
|
|
|
/* Actual code that puts the SoC in different idle states */
|
|
static int zynq_enter_idle(struct cpuidle_device *dev,
|
|
struct cpuidle_driver *drv, int index)
|
|
{
|
|
/* Add code for DDR self refresh start */
|
|
cpu_do_idle();
|
|
|
|
return index;
|
|
}
|
|
|
|
static struct cpuidle_driver zynq_idle_driver = {
|
|
.name = "zynq_idle",
|
|
.owner = THIS_MODULE,
|
|
.states = {
|
|
ARM_CPUIDLE_WFI_STATE,
|
|
{
|
|
.enter = zynq_enter_idle,
|
|
.exit_latency = 10,
|
|
.target_residency = 10000,
|
|
.flags = CPUIDLE_FLAG_TIME_VALID,
|
|
.name = "RAM_SR",
|
|
.desc = "WFI and RAM Self Refresh",
|
|
},
|
|
},
|
|
.safe_state_index = 0,
|
|
.state_count = ZYNQ_MAX_STATES,
|
|
};
|
|
|
|
/* Initialize CPU idle by registering the idle states */
|
|
static int zynq_cpuidle_probe(struct platform_device *pdev)
|
|
{
|
|
pr_info("Xilinx Zynq CpuIdle Driver started\n");
|
|
|
|
return cpuidle_register(&zynq_idle_driver, NULL);
|
|
}
|
|
|
|
static struct platform_driver zynq_cpuidle_driver = {
|
|
.driver = {
|
|
.name = "cpuidle-zynq",
|
|
.owner = THIS_MODULE,
|
|
},
|
|
.probe = zynq_cpuidle_probe,
|
|
};
|
|
|
|
module_platform_driver(zynq_cpuidle_driver);
|