1 /*
2  * Copyright 2012 Calxeda, Inc.
3  *
4  * Based on arch/arm/plat-mxc/cpuidle.c: #v3.7
5  * Copyright 2012 Freescale Semiconductor, Inc.
6  * Copyright 2012 Linaro Ltd.
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms and conditions of the GNU General Public License,
10  * version 2, as published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope it will be useful, but WITHOUT
13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
15  * more details.
16  *
17  * You should have received a copy of the GNU General Public License along with
18  * this program.  If not, see <http://www.gnu.org/licenses/>.
19  *
20  * Maintainer: Rob Herring <rob.herring@calxeda.com>
21  */
22 
23 #include <linux/cpuidle.h>
24 #include <linux/cpu_pm.h>
25 #include <linux/init.h>
26 #include <linux/mm.h>
27 #include <linux/platform_device.h>
28 #include <linux/psci.h>
29 
30 #include <asm/cpuidle.h>
31 #include <asm/suspend.h>
32 
33 #include <uapi/linux/psci.h>
34 
35 #define CALXEDA_IDLE_PARAM \
36 	((0 << PSCI_0_2_POWER_STATE_ID_SHIFT) | \
37 	 (0 << PSCI_0_2_POWER_STATE_AFFL_SHIFT) | \
38 	 (PSCI_POWER_STATE_TYPE_POWER_DOWN << PSCI_0_2_POWER_STATE_TYPE_SHIFT))
39 
calxeda_idle_finish(unsigned long val)40 static int calxeda_idle_finish(unsigned long val)
41 {
42 	return psci_ops.cpu_suspend(CALXEDA_IDLE_PARAM, __pa(cpu_resume));
43 }
44 
calxeda_pwrdown_idle(struct cpuidle_device * dev,struct cpuidle_driver * drv,int index)45 static int calxeda_pwrdown_idle(struct cpuidle_device *dev,
46 				struct cpuidle_driver *drv,
47 				int index)
48 {
49 	cpu_pm_enter();
50 	cpu_suspend(0, calxeda_idle_finish);
51 	cpu_pm_exit();
52 
53 	return index;
54 }
55 
56 static struct cpuidle_driver calxeda_idle_driver = {
57 	.name = "calxeda_idle",
58 	.states = {
59 		ARM_CPUIDLE_WFI_STATE,
60 		{
61 			.name = "PG",
62 			.desc = "Power Gate",
63 			.exit_latency = 30,
64 			.power_usage = 50,
65 			.target_residency = 200,
66 			.enter = calxeda_pwrdown_idle,
67 		},
68 	},
69 	.state_count = 2,
70 };
71 
calxeda_cpuidle_probe(struct platform_device * pdev)72 static int calxeda_cpuidle_probe(struct platform_device *pdev)
73 {
74 	return cpuidle_register(&calxeda_idle_driver, NULL);
75 }
76 
77 static struct platform_driver calxeda_cpuidle_plat_driver = {
78         .driver = {
79                 .name = "cpuidle-calxeda",
80         },
81         .probe = calxeda_cpuidle_probe,
82 };
83 builtin_platform_driver(calxeda_cpuidle_plat_driver);
84