Commit | Line | Data |
---|---|---|
9952f691 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
bd2a337a MS |
2 | /* |
3 | * Copyright (C) 2012-2013 Xilinx | |
4 | * | |
5 | * CPU idle support for Xilinx Zynq | |
6 | * | |
7 | * based on arch/arm/mach-at91/cpuidle.c | |
8 | * | |
bd2a337a MS |
9 | * The cpu idle uses wait-for-interrupt and RAM self refresh in order |
10 | * to implement two idle states - | |
11 | * #1 wait-for-interrupt | |
12 | * #2 wait-for-interrupt and RAM self refresh | |
13 | * | |
14 | * Maintainer: Michal Simek <michal.simek@xilinx.com> | |
15 | */ | |
16 | ||
17 | #include <linux/init.h> | |
bd2a337a | 18 | #include <linux/cpuidle.h> |
3e8ceca6 | 19 | #include <linux/platform_device.h> |
bd2a337a MS |
20 | #include <asm/cpuidle.h> |
21 | ||
22 | #define ZYNQ_MAX_STATES 2 | |
23 | ||
24 | /* Actual code that puts the SoC in different idle states */ | |
25 | static int zynq_enter_idle(struct cpuidle_device *dev, | |
26 | struct cpuidle_driver *drv, int index) | |
27 | { | |
bd2a337a MS |
28 | /* Add code for DDR self refresh start */ |
29 | cpu_do_idle(); | |
30 | ||
bd2a337a MS |
31 | return index; |
32 | } | |
33 | ||
34 | static struct cpuidle_driver zynq_idle_driver = { | |
35 | .name = "zynq_idle", | |
36 | .owner = THIS_MODULE, | |
37 | .states = { | |
38 | ARM_CPUIDLE_WFI_STATE, | |
39 | { | |
40 | .enter = zynq_enter_idle, | |
41 | .exit_latency = 10, | |
42 | .target_residency = 10000, | |
bd2a337a MS |
43 | .name = "RAM_SR", |
44 | .desc = "WFI and RAM Self Refresh", | |
45 | }, | |
46 | }, | |
47 | .safe_state_index = 0, | |
48 | .state_count = ZYNQ_MAX_STATES, | |
49 | }; | |
50 | ||
51 | /* Initialize CPU idle by registering the idle states */ | |
3e8ceca6 | 52 | static int zynq_cpuidle_probe(struct platform_device *pdev) |
bd2a337a | 53 | { |
bd2a337a MS |
54 | pr_info("Xilinx Zynq CpuIdle Driver started\n"); |
55 | ||
56 | return cpuidle_register(&zynq_idle_driver, NULL); | |
57 | } | |
58 | ||
3e8ceca6 DL |
59 | static struct platform_driver zynq_cpuidle_driver = { |
60 | .driver = { | |
61 | .name = "cpuidle-zynq", | |
3e8ceca6 DL |
62 | }, |
63 | .probe = zynq_cpuidle_probe, | |
64 | }; | |
090d1cf1 | 65 | builtin_platform_driver(zynq_cpuidle_driver); |