projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 12bb3440 SG |
1 | /* |
| 2 | * Copyright (C) 2012 Freescale Semiconductor, Inc. | |
| 3 | * | |
| 4 | * This program is free software; you can redistribute it and/or modify | |
| 5 | * it under the terms of the GNU General Public License version 2 as | |
| 6 | * published by the Free Software Foundation. | |
| 7 | */ | |
| 8 | ||
| 9 | #include <linux/cpuidle.h> | |
| 10 | #include <linux/module.h> | |
| 11 | #include <asm/cpuidle.h> | |
| e5f9dec8 | 12 | #include <asm/proc-fns.h> |
| 12bb3440 | 13 | |
| e5f9dec8 | 14 | #include "common.h" |
| 12bb3440 | 15 | #include "cpuidle.h" |
| a25d67a4 | 16 | #include "hardware.h" |
| 12bb3440 | 17 | |
| e5f9dec8 SG |
18 | static atomic_t master = ATOMIC_INIT(0); |
| 19 | static DEFINE_SPINLOCK(master_lock); | |
| 20 | ||
| 21 | static int imx6q_enter_wait(struct cpuidle_device *dev, | |
| 22 | struct cpuidle_driver *drv, int index) | |
| 23 | { | |
| e5f9dec8 SG |
24 | if (atomic_inc_return(&master) == num_online_cpus()) { |
| 25 | /* | |
| 26 | * With this lock, we prevent other cpu to exit and enter | |
| 27 | * this function again and become the master. | |
| 28 | */ | |
| 29 | if (!spin_trylock(&master_lock)) | |
| 30 | goto idle; | |
| 31 | imx6q_set_lpm(WAIT_UNCLOCKED); | |
| 32 | cpu_do_idle(); | |
| 33 | imx6q_set_lpm(WAIT_CLOCKED); | |
| 34 | spin_unlock(&master_lock); | |
| 35 | goto done; | |
| 36 | } | |
| 37 | ||
| 38 | idle: | |
| 39 | cpu_do_idle(); | |
| 40 | done: | |
| 41 | atomic_dec(&master); | |
| e5f9dec8 SG |
42 | |
| 43 | return index; | |
| 44 | } | |
| 45 | ||
| 12bb3440 SG |
46 | static struct cpuidle_driver imx6q_cpuidle_driver = { |
| 47 | .name = "imx6q_cpuidle", | |
| 48 | .owner = THIS_MODULE, | |
| e5f9dec8 SG |
49 | .states = { |
| 50 | /* WFI */ | |
| 51 | ARM_CPUIDLE_WFI_STATE, | |
| 52 | /* WAIT */ | |
| 53 | { | |
| 54 | .exit_latency = 50, | |
| 55 | .target_residency = 75, | |
| b82b6cca | 56 | .flags = CPUIDLE_FLAG_TIMER_STOP, |
| e5f9dec8 SG |
57 | .enter = imx6q_enter_wait, |
| 58 | .name = "WAIT", | |
| 59 | .desc = "Clock off", | |
| 60 | }, | |
| 61 | }, | |
| 62 | .state_count = 2, | |
| 63 | .safe_state_index = 0, | |
| 12bb3440 SG |
64 | }; |
| 65 | ||
| 66 | int __init imx6q_cpuidle_init(void) | |
| 67 | { | |
| fa6be65e | 68 | /* Set INT_MEM_CLK_LPM bit to get a reliable WAIT mode support */ |
| dfea953a | 69 | imx6q_set_int_mem_clk_lpm(true); |
| e5f9dec8 | 70 | |
| 54a4644b | 71 | return cpuidle_register(&imx6q_cpuidle_driver, NULL); |
| 12bb3440 | 72 | } |