| rjw | 1f88458 | 2022-01-06 17:20:42 +0800 | [diff] [blame^] | 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> |
| 12 | |
| 13 | #include <soc/imx/cpuidle.h> |
| 14 | |
| 15 | #include "common.h" |
| 16 | #include "cpuidle.h" |
| 17 | #include "hardware.h" |
| 18 | |
| 19 | static int num_idle_cpus = 0; |
| 20 | static DEFINE_SPINLOCK(cpuidle_lock); |
| 21 | |
| 22 | static int imx6q_enter_wait(struct cpuidle_device *dev, |
| 23 | struct cpuidle_driver *drv, int index) |
| 24 | { |
| 25 | spin_lock(&cpuidle_lock); |
| 26 | if (++num_idle_cpus == num_online_cpus()) |
| 27 | imx6_set_lpm(WAIT_UNCLOCKED); |
| 28 | spin_unlock(&cpuidle_lock); |
| 29 | |
| 30 | cpu_do_idle(); |
| 31 | |
| 32 | spin_lock(&cpuidle_lock); |
| 33 | if (num_idle_cpus-- == num_online_cpus()) |
| 34 | imx6_set_lpm(WAIT_CLOCKED); |
| 35 | spin_unlock(&cpuidle_lock); |
| 36 | |
| 37 | return index; |
| 38 | } |
| 39 | |
| 40 | static struct cpuidle_driver imx6q_cpuidle_driver = { |
| 41 | .name = "imx6q_cpuidle", |
| 42 | .owner = THIS_MODULE, |
| 43 | .states = { |
| 44 | /* WFI */ |
| 45 | ARM_CPUIDLE_WFI_STATE, |
| 46 | /* WAIT */ |
| 47 | { |
| 48 | .exit_latency = 50, |
| 49 | .target_residency = 75, |
| 50 | .flags = CPUIDLE_FLAG_TIMER_STOP, |
| 51 | .enter = imx6q_enter_wait, |
| 52 | .name = "WAIT", |
| 53 | .desc = "Clock off", |
| 54 | }, |
| 55 | }, |
| 56 | .state_count = 2, |
| 57 | .safe_state_index = 0, |
| 58 | }; |
| 59 | |
| 60 | /* |
| 61 | * i.MX6 Q/DL has an erratum (ERR006687) that prevents the FEC from waking the |
| 62 | * CPUs when they are in wait(unclocked) state. As the hardware workaround isn't |
| 63 | * applicable to all boards, disable the deeper idle state when the workaround |
| 64 | * isn't present and the FEC is in use. |
| 65 | */ |
| 66 | void imx6q_cpuidle_fec_irqs_used(void) |
| 67 | { |
| 68 | imx6q_cpuidle_driver.states[1].disabled = true; |
| 69 | } |
| 70 | EXPORT_SYMBOL_GPL(imx6q_cpuidle_fec_irqs_used); |
| 71 | |
| 72 | void imx6q_cpuidle_fec_irqs_unused(void) |
| 73 | { |
| 74 | imx6q_cpuidle_driver.states[1].disabled = false; |
| 75 | } |
| 76 | EXPORT_SYMBOL_GPL(imx6q_cpuidle_fec_irqs_unused); |
| 77 | |
| 78 | int __init imx6q_cpuidle_init(void) |
| 79 | { |
| 80 | /* Set INT_MEM_CLK_LPM bit to get a reliable WAIT mode support */ |
| 81 | imx6_set_int_mem_clk_lpm(true); |
| 82 | |
| 83 | return cpuidle_register(&imx6q_cpuidle_driver, NULL); |
| 84 | } |