| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Copyright (C) 2012 Freescale Semiconductor, Inc. |
| */ |
| |
| #include <linux/context_tracking.h> |
| #include <linux/cpuidle.h> |
| #include <linux/module.h> |
| #include <asm/cpuidle.h> |
| |
| #include <soc/imx/cpuidle.h> |
| |
| #include "common.h" |
| #include "cpuidle.h" |
| #include "hardware.h" |
| |
| static int num_idle_cpus = 0; |
| static DEFINE_RAW_SPINLOCK(cpuidle_lock); |
| |
| static __cpuidle int imx6q_enter_wait(struct cpuidle_device *dev, |
| struct cpuidle_driver *drv, int index) |
| { |
| raw_spin_lock(&cpuidle_lock); |
| if (++num_idle_cpus == num_online_cpus()) |
| imx6_set_lpm(WAIT_UNCLOCKED); |
| raw_spin_unlock(&cpuidle_lock); |
| |
| ct_cpuidle_enter(); |
| cpu_do_idle(); |
| ct_cpuidle_exit(); |
| |
| raw_spin_lock(&cpuidle_lock); |
| if (num_idle_cpus-- == num_online_cpus()) |
| imx6_set_lpm(WAIT_CLOCKED); |
| raw_spin_unlock(&cpuidle_lock); |
| |
| return index; |
| } |
| |
| static struct cpuidle_driver imx6q_cpuidle_driver = { |
| .name = "imx6q_cpuidle", |
| .owner = THIS_MODULE, |
| .states = { |
| /* WFI */ |
| ARM_CPUIDLE_WFI_STATE, |
| /* WAIT */ |
| { |
| .exit_latency = 50, |
| .target_residency = 75, |
| .flags = CPUIDLE_FLAG_TIMER_STOP | CPUIDLE_FLAG_RCU_IDLE, |
| .enter = imx6q_enter_wait, |
| .name = "WAIT", |
| .desc = "Clock off", |
| }, |
| }, |
| .state_count = 2, |
| .safe_state_index = 0, |
| }; |
| |
| /* |
| * i.MX6 Q/DL has an erratum (ERR006687) that prevents the FEC from waking the |
| * CPUs when they are in wait(unclocked) state. As the hardware workaround isn't |
| * applicable to all boards, disable the deeper idle state when the workaround |
| * isn't present and the FEC is in use. |
| */ |
| void imx6q_cpuidle_fec_irqs_used(void) |
| { |
| cpuidle_driver_state_disabled(&imx6q_cpuidle_driver, 1, true); |
| } |
| EXPORT_SYMBOL_GPL(imx6q_cpuidle_fec_irqs_used); |
| |
| void imx6q_cpuidle_fec_irqs_unused(void) |
| { |
| cpuidle_driver_state_disabled(&imx6q_cpuidle_driver, 1, false); |
| } |
| EXPORT_SYMBOL_GPL(imx6q_cpuidle_fec_irqs_unused); |
| |
| int __init imx6q_cpuidle_init(void) |
| { |
| /* Set INT_MEM_CLK_LPM bit to get a reliable WAIT mode support */ |
| imx6_set_int_mem_clk_lpm(true); |
| |
| return cpuidle_register(&imx6q_cpuidle_driver, NULL); |
| } |