f9e9fc2736
Adds initial low power suspend functionality to MX51. Supports "mem" and "standby" modes. Tested on mx51-babbage. Signed-off-by: Dinh Nguyen <Dinh.Nguyen@freescale.com> Tested-by: Arnaud Patard <arnaud.patard@rtp-net.org> Tested-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
74 lines
1.6 KiB
C
74 lines
1.6 KiB
C
/*
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* Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
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*
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* The code contained herein is licensed under the GNU General Public
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* License. You may obtain a copy of the GNU General Public License
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* Version 2 or later at the following locations:
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*
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* http://www.opensource.org/licenses/gpl-license.html
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* http://www.gnu.org/copyleft/gpl.html
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*/
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#include <linux/suspend.h>
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#include <linux/clk.h>
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#include <linux/io.h>
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#include <linux/err.h>
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#include <asm/cacheflush.h>
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#include <asm/tlbflush.h>
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#include <mach/system.h>
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#include "crm_regs.h"
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static struct clk *gpc_dvfs_clk;
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static int mx5_suspend_enter(suspend_state_t state)
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{
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clk_enable(gpc_dvfs_clk);
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switch (state) {
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case PM_SUSPEND_MEM:
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mx5_cpu_lp_set(STOP_POWER_OFF);
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break;
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case PM_SUSPEND_STANDBY:
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mx5_cpu_lp_set(WAIT_UNCLOCKED_POWER_OFF);
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break;
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default:
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return -EINVAL;
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}
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if (state == PM_SUSPEND_MEM) {
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local_flush_tlb_all();
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flush_cache_all();
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/*clear the EMPGC0/1 bits */
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__raw_writel(0, MXC_SRPG_EMPGC0_SRPGCR);
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__raw_writel(0, MXC_SRPG_EMPGC1_SRPGCR);
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}
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cpu_do_idle();
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clk_disable(gpc_dvfs_clk);
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return 0;
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}
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static int mx5_pm_valid(suspend_state_t state)
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{
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return (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX);
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}
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static const struct platform_suspend_ops mx5_suspend_ops = {
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.valid = mx5_pm_valid,
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.enter = mx5_suspend_enter,
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};
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static int __init mx5_pm_init(void)
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{
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if (gpc_dvfs_clk == NULL)
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gpc_dvfs_clk = clk_get(NULL, "gpc_dvfs");
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if (!IS_ERR(gpc_dvfs_clk)) {
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if (cpu_is_mx51())
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suspend_set_ops(&mx5_suspend_ops);
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} else
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return -EPERM;
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return 0;
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}
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device_initcall(mx5_pm_init);
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