projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| e50b6bef | 1 | /* |
| e50b6bef RK |
2 | * CPU idle Marvell Kirkwood SoCs |
| 3 | * | |
| 4 | * This file is licensed under the terms of the GNU General Public | |
| 5 | * License version 2. This program is licensed "as is" without any | |
| 6 | * warranty of any kind, whether express or implied. | |
| 7 | * | |
| 8 | * The cpu idle uses wait-for-interrupt and DDR self refresh in order | |
| 9 | * to implement two idle states - | |
| 10 | * #1 wait-for-interrupt | |
| 11 | * #2 wait-for-interrupt and DDR self refresh | |
| a8e39c35 DL |
12 | * |
| 13 | * Maintainer: Jason Cooper <jason@lakedaemon.net> | |
| 14 | * Maintainer: Andrew Lunn <andrew@lunn.ch> | |
| e50b6bef RK |
15 | */ |
| 16 | ||
| 17 | #include <linux/kernel.h> | |
| 9cfc94eb | 18 | #include <linux/module.h> |
| e50b6bef RK |
19 | #include <linux/init.h> |
| 20 | #include <linux/platform_device.h> | |
| 21 | #include <linux/cpuidle.h> | |
| 22 | #include <linux/io.h> | |
| dc28094b | 23 | #include <linux/export.h> |
| b334648d | 24 | #include <asm/cpuidle.h> |
| e50b6bef RK |
25 | |
| 26 | #define KIRKWOOD_MAX_STATES 2 | |
| 27 | ||
| 9cfc94eb AL |
28 | static void __iomem *ddr_operation_base; |
| 29 | ||
| e50b6bef RK |
30 | /* Actual code that puts the SoC in different idle states */ |
| 31 | static int kirkwood_enter_idle(struct cpuidle_device *dev, | |
| 9cfc94eb | 32 | struct cpuidle_driver *drv, |
| e978aa7d | 33 | int index) |
| e50b6bef | 34 | { |
| 9cfc94eb | 35 | writel(0x7, ddr_operation_base); |
| b334648d | 36 | cpu_do_idle(); |
| e978aa7d DD |
37 | |
| 38 | return index; | |
| e50b6bef RK |
39 | } |
| 40 | ||
| b334648d RL |
41 | static struct cpuidle_driver kirkwood_idle_driver = { |
| 42 | .name = "kirkwood_idle", | |
| 43 | .owner = THIS_MODULE, | |
| b334648d RL |
44 | .states[0] = ARM_CPUIDLE_WFI_STATE, |
| 45 | .states[1] = { | |
| 46 | .enter = kirkwood_enter_idle, | |
| 47 | .exit_latency = 10, | |
| 48 | .target_residency = 100000, | |
| b334648d RL |
49 | .name = "DDR SR", |
| 50 | .desc = "WFI and DDR Self Refresh", | |
| 51 | }, | |
| 52 | .state_count = KIRKWOOD_MAX_STATES, | |
| 53 | }; | |
| b334648d | 54 | |
| e50b6bef | 55 | /* Initialize CPU idle by registering the idle states */ |
| 9cfc94eb | 56 | static int kirkwood_cpuidle_probe(struct platform_device *pdev) |
| e50b6bef | 57 | { |
| 85c3ebd4 | 58 | ddr_operation_base = devm_platform_ioremap_resource(pdev, 0); |
| 488540bf SMP |
59 | if (IS_ERR(ddr_operation_base)) |
| 60 | return PTR_ERR(ddr_operation_base); | |
| e50b6bef | 61 | |
| 30dc72c6 | 62 | return cpuidle_register(&kirkwood_idle_driver, NULL); |
| e50b6bef RK |
63 | } |
| 64 | ||
| 75d6137d | 65 | static int kirkwood_cpuidle_remove(struct platform_device *pdev) |
| 9cfc94eb | 66 | { |
| 30dc72c6 | 67 | cpuidle_unregister(&kirkwood_idle_driver); |
| 9cfc94eb AL |
68 | return 0; |
| 69 | } | |
| 70 | ||
| 71 | static struct platform_driver kirkwood_cpuidle_driver = { | |
| 72 | .probe = kirkwood_cpuidle_probe, | |
| 73 | .remove = kirkwood_cpuidle_remove, | |
| 74 | .driver = { | |
| 75 | .name = "kirkwood_cpuidle", | |
| 9cfc94eb AL |
76 | }, |
| 77 | }; | |
| 78 | ||
| 79 | module_platform_driver(kirkwood_cpuidle_driver); | |
| 80 | ||
| 81 | MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>"); | |
| 82 | MODULE_DESCRIPTION("Kirkwood cpu idle driver"); | |
| 83 | MODULE_LICENSE("GPL v2"); | |
| 84 | MODULE_ALIAS("platform:kirkwood-cpuidle"); |