1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright (C) 2012 Freescale Semiconductor, Inc. |
4 | */ |
5 | |
6 | #include <linux/context_tracking.h> |
7 | #include <linux/cpuidle.h> |
8 | #include <linux/module.h> |
9 | #include <asm/cpuidle.h> |
10 | |
11 | #include <soc/imx/cpuidle.h> |
12 | |
13 | #include "common.h" |
14 | #include "cpuidle.h" |
15 | #include "hardware.h" |
16 | |
17 | static int num_idle_cpus = 0; |
18 | static DEFINE_RAW_SPINLOCK(cpuidle_lock); |
19 | |
20 | static __cpuidle int imx6q_enter_wait(struct cpuidle_device *dev, |
21 | struct cpuidle_driver *drv, int index) |
22 | { |
23 | raw_spin_lock(&cpuidle_lock); |
24 | if (++num_idle_cpus == num_online_cpus()) |
25 | imx6_set_lpm(mode: WAIT_UNCLOCKED); |
26 | raw_spin_unlock(&cpuidle_lock); |
27 | |
28 | ct_cpuidle_enter(); |
29 | cpu_do_idle(); |
30 | ct_cpuidle_exit(); |
31 | |
32 | raw_spin_lock(&cpuidle_lock); |
33 | if (num_idle_cpus-- == num_online_cpus()) |
34 | imx6_set_lpm(mode: WAIT_CLOCKED); |
35 | raw_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 | CPUIDLE_FLAG_RCU_IDLE, |
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 | cpuidle_driver_state_disabled(drv: &imx6q_cpuidle_driver, idx: 1, disable: true); |
69 | } |
70 | EXPORT_SYMBOL_GPL(imx6q_cpuidle_fec_irqs_used); |
71 | |
72 | void imx6q_cpuidle_fec_irqs_unused(void) |
73 | { |
74 | cpuidle_driver_state_disabled(drv: &imx6q_cpuidle_driver, idx: 1, disable: 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(enable: true); |
82 | |
83 | return cpuidle_register(drv: &imx6q_cpuidle_driver, NULL); |
84 | } |
85 | |