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authorLinus Torvalds <torvalds@linux-foundation.org>2012-05-22 12:41:01 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-05-22 12:41:01 -0400
commitcdd3a354a05b0c33fe33ab11a0fb0838396cad19 (patch)
treeea2c87bbc2dc5865a97e73e201661d69937b45d5 /arch/arm/mach-ux500
parent813a95e5b4fa936bbde10ef89188932745dcd7f4 (diff)
parentada2e35defe6c6f0a986ec8147e47726fbd0e7b1 (diff)
Merge tag 'pm' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull arm-soc power management changes from Olof Johansson: "Power management changes here are mostly for the omap platform, but also include cpuidle changes for ux500 and suspend/resume code for mmp." * tag 'pm' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (48 commits) ARM: OMAP2+: WDTIMER integration: fix !PM boot crash, disarm timer after hwmod reset ARM: OMAP2/3: hwmod data: Add 32k-sync timer data to hwmod database ARM: OMAP4: hwmod_data: Name the common irq for McBSP ports ARM: OMAP4: hwmod data: I2C: add flag for context restore ARM: OMAP3: hwmod_data: Rename the common irq for McBSP ports ARM: OMAP2xxx: hwmod data: add HDQ/1-wire hwmod ARM: OMAP3: hwmod data: add HDQ/1-wire hwmod ARM: OMAP2+: hwmod data: add HDQ/1-wire hwmod shared data ARM: OMAP2+: HDQ1W: add custom reset function ARM: OMAP2420: hwmod data: Add MMC hwmod data for 2420 arm: omap3: clockdomain data: Remove superfluous commas from gfx_sgx_3xxx_wkdeps[] ARM: OMAP2+: powerdomain: Get rid off duplicate pwrdm_clkdm_state_switch() API ARM: OMAP3: clock data: add clockdomain for HDQ functional clock ARM: OMAP3+: dpll: Configure autoidle mode only if it's supported ARM: OMAP2+: dmtimer: cleanup iclk usage ARM: OMAP4+: Add prm and cm base init function. ARM: OMAP2/3: Add idle_st bits for ST_32KSYNC timer to prcm-common header ARM: OMAP3: Fix CM register bit masks ARM: OMAP: clock: convert AM3517/3505 detection/flags to AM35xx ARM: OMAP3: clock data: treat all AM35x devices the same ...
Diffstat (limited to 'arch/arm/mach-ux500')
-rw-r--r--arch/arm/mach-ux500/Makefile1
-rw-r--r--arch/arm/mach-ux500/cpuidle.c171
2 files changed, 172 insertions, 0 deletions
diff --git a/arch/arm/mach-ux500/Makefile b/arch/arm/mach-ux500/Makefile
index 041c35885981..026086ff9e6c 100644
--- a/arch/arm/mach-ux500/Makefile
+++ b/arch/arm/mach-ux500/Makefile
@@ -4,6 +4,7 @@
4 4
5obj-y := clock.o cpu.o devices.o devices-common.o \ 5obj-y := clock.o cpu.o devices.o devices-common.o \
6 id.o usb.o timer.o 6 id.o usb.o timer.o
7obj-$(CONFIG_CPU_IDLE) += cpuidle.o
7obj-$(CONFIG_CACHE_L2X0) += cache-l2x0.o 8obj-$(CONFIG_CACHE_L2X0) += cache-l2x0.o
8obj-$(CONFIG_UX500_SOC_DB8500) += cpu-db8500.o devices-db8500.o 9obj-$(CONFIG_UX500_SOC_DB8500) += cpu-db8500.o devices-db8500.o
9obj-$(CONFIG_MACH_MOP500) += board-mop500.o board-mop500-sdi.o \ 10obj-$(CONFIG_MACH_MOP500) += board-mop500.o board-mop500-sdi.o \
diff --git a/arch/arm/mach-ux500/cpuidle.c b/arch/arm/mach-ux500/cpuidle.c
new file mode 100644
index 000000000000..b54884bd2549
--- /dev/null
+++ b/arch/arm/mach-ux500/cpuidle.c
@@ -0,0 +1,171 @@
1/*
2 * Copyright (c) 2012 Linaro : Daniel Lezcano <daniel.lezcano@linaro.org> (IBM)
3 *
4 * Based on the work of Rickard Andersson <rickard.andersson@stericsson.com>
5 * and Jonas Aaberg <jonas.aberg@stericsson.com>.
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12#include <linux/module.h>
13#include <linux/cpuidle.h>
14#include <linux/clockchips.h>
15#include <linux/spinlock.h>
16#include <linux/atomic.h>
17#include <linux/smp.h>
18#include <linux/mfd/dbx500-prcmu.h>
19
20#include <asm/cpuidle.h>
21#include <asm/proc-fns.h>
22
23static atomic_t master = ATOMIC_INIT(0);
24static DEFINE_SPINLOCK(master_lock);
25static DEFINE_PER_CPU(struct cpuidle_device, ux500_cpuidle_device);
26
27static inline int ux500_enter_idle(struct cpuidle_device *dev,
28 struct cpuidle_driver *drv, int index)
29{
30 int this_cpu = smp_processor_id();
31 bool recouple = false;
32
33 clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &this_cpu);
34
35 if (atomic_inc_return(&master) == num_online_cpus()) {
36
37 /* With this lock, we prevent the other cpu to exit and enter
38 * this function again and become the master */
39 if (!spin_trylock(&master_lock))
40 goto wfi;
41
42 /* decouple the gic from the A9 cores */
43 if (prcmu_gic_decouple())
44 goto out;
45
46 /* If an error occur, we will have to recouple the gic
47 * manually */
48 recouple = true;
49
50 /* At this state, as the gic is decoupled, if the other
51 * cpu is in WFI, we have the guarantee it won't be wake
52 * up, so we can safely go to retention */
53 if (!prcmu_is_cpu_in_wfi(this_cpu ? 0 : 1))
54 goto out;
55
56 /* The prcmu will be in charge of watching the interrupts
57 * and wake up the cpus */
58 if (prcmu_copy_gic_settings())
59 goto out;
60
61 /* Check in the meantime an interrupt did
62 * not occur on the gic ... */
63 if (prcmu_gic_pending_irq())
64 goto out;
65
66 /* ... and the prcmu */
67 if (prcmu_pending_irq())
68 goto out;
69
70 /* Go to the retention state, the prcmu will wait for the
71 * cpu to go WFI and this is what happens after exiting this
72 * 'master' critical section */
73 if (prcmu_set_power_state(PRCMU_AP_IDLE, true, true))
74 goto out;
75
76 /* When we switch to retention, the prcmu is in charge
77 * of recoupling the gic automatically */
78 recouple = false;
79
80 spin_unlock(&master_lock);
81 }
82wfi:
83 cpu_do_idle();
84out:
85 atomic_dec(&master);
86
87 if (recouple) {
88 prcmu_gic_recouple();
89 spin_unlock(&master_lock);
90 }
91
92 clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &this_cpu);
93
94 return index;
95}
96
97static struct cpuidle_driver ux500_idle_driver = {
98 .name = "ux500_idle",
99 .owner = THIS_MODULE,
100 .en_core_tk_irqen = 1,
101 .states = {
102 ARM_CPUIDLE_WFI_STATE,
103 {
104 .enter = ux500_enter_idle,
105 .exit_latency = 70,
106 .target_residency = 260,
107 .flags = CPUIDLE_FLAG_TIME_VALID,
108 .name = "ApIdle",
109 .desc = "ARM Retention",
110 },
111 },
112 .safe_state_index = 0,
113 .state_count = 2,
114};
115
116/*
117 * For each cpu, setup the broadcast timer because we will
118 * need to migrate the timers for the states >= ApIdle.
119 */
120static void ux500_setup_broadcast_timer(void *arg)
121{
122 int cpu = smp_processor_id();
123 clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ON, &cpu);
124}
125
126int __init ux500_idle_init(void)
127{
128 int ret, cpu;
129 struct cpuidle_device *device;
130
131 /* Configure wake up reasons */
132 prcmu_enable_wakeups(PRCMU_WAKEUP(ARM) | PRCMU_WAKEUP(RTC) |
133 PRCMU_WAKEUP(ABB));
134
135 /*
136 * Configure the timer broadcast for each cpu, that must
137 * be done from the cpu context, so we use a smp cross
138 * call with 'on_each_cpu'.
139 */
140 on_each_cpu(ux500_setup_broadcast_timer, NULL, 1);
141
142 ret = cpuidle_register_driver(&ux500_idle_driver);
143 if (ret) {
144 printk(KERN_ERR "failed to register ux500 idle driver\n");
145 return ret;
146 }
147
148 for_each_online_cpu(cpu) {
149 device = &per_cpu(ux500_cpuidle_device, cpu);
150 device->cpu = cpu;
151 ret = cpuidle_register_device(device);
152 if (ret) {
153 printk(KERN_ERR "Failed to register cpuidle "
154 "device for cpu%d\n", cpu);
155 goto out_unregister;
156 }
157 }
158out:
159 return ret;
160
161out_unregister:
162 for_each_online_cpu(cpu) {
163 device = &per_cpu(ux500_cpuidle_device, cpu);
164 cpuidle_unregister_device(device);
165 }
166
167 cpuidle_unregister_driver(&ux500_idle_driver);
168 goto out;
169}
170
171device_initcall(ux500_idle_init);