mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-05 01:54:09 +08:00
e1cb367de2
Implements standby support for Kirkwood SoC. When the SoC enters standby state the memory PM units are disabled, the DDR is set in self-refresh mode, and the CPU is set in WFI. At this point there's no clock gating, as that is considered each driver's task. Signed-off-by: Simon Guinot <sguinot@lacie.com> Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com> Signed-off-by: Jason Cooper <jason@lakedaemon.net>
74 lines
1.7 KiB
C
74 lines
1.7 KiB
C
/*
|
|
* Power Management driver for Marvell Kirkwood SoCs
|
|
*
|
|
* Copyright (C) 2013 Ezequiel Garcia <ezequiel@free-electrons.com>
|
|
* Copyright (C) 2010 Simon Guinot <sguinot@lacie.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License,
|
|
* version 2 of the License.
|
|
*
|
|
* This program is distributed in the hope that 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.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/suspend.h>
|
|
#include <linux/io.h>
|
|
#include <mach/bridge-regs.h>
|
|
|
|
static void __iomem *ddr_operation_base;
|
|
|
|
static void kirkwood_low_power(void)
|
|
{
|
|
u32 mem_pm_ctrl;
|
|
|
|
mem_pm_ctrl = readl(MEMORY_PM_CTRL);
|
|
|
|
/* Set peripherals to low-power mode */
|
|
writel_relaxed(~0, MEMORY_PM_CTRL);
|
|
|
|
/* Set DDR in self-refresh */
|
|
writel_relaxed(0x7, ddr_operation_base);
|
|
|
|
/*
|
|
* Set CPU in wait-for-interrupt state.
|
|
* This disables the CPU core clocks,
|
|
* the array clocks, and also the L2 controller.
|
|
*/
|
|
cpu_do_idle();
|
|
|
|
writel_relaxed(mem_pm_ctrl, MEMORY_PM_CTRL);
|
|
}
|
|
|
|
static int kirkwood_suspend_enter(suspend_state_t state)
|
|
{
|
|
switch (state) {
|
|
case PM_SUSPEND_STANDBY:
|
|
kirkwood_low_power();
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int kirkwood_pm_valid_standby(suspend_state_t state)
|
|
{
|
|
return state == PM_SUSPEND_STANDBY;
|
|
}
|
|
|
|
static const struct platform_suspend_ops kirkwood_suspend_ops = {
|
|
.enter = kirkwood_suspend_enter,
|
|
.valid = kirkwood_pm_valid_standby,
|
|
};
|
|
|
|
int __init kirkwood_pm_init(void)
|
|
{
|
|
ddr_operation_base = ioremap(DDR_OPERATION_BASE, 4);
|
|
suspend_set_ops(&kirkwood_suspend_ops);
|
|
return 0;
|
|
}
|