projects / mirror_ubuntu-zesty-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 64909882 | 1 | /* |
| 73cc9c8c | 2 | * clock scaling for the UniCore-II |
| 64909882 G |
3 | * |
| 4 | * Code specific to PKUnity SoC and UniCore ISA | |
| 5 | * | |
| 6 | * Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn> | |
| 7 | * Copyright (C) 2001-2010 Guan Xuetao | |
| 8 | * | |
| 9 | * This program is free software; you can redistribute it and/or modify | |
| 10 | * it under the terms of the GNU General Public License version 2 as | |
| 11 | * published by the Free Software Foundation. | |
| 12 | */ | |
| 13 | ||
| 652ed95d | 14 | #include <linux/err.h> |
| 64909882 G |
15 | #include <linux/kernel.h> |
| 16 | #include <linux/types.h> | |
| 17 | #include <linux/init.h> | |
| 18 | #include <linux/clk.h> | |
| 19 | #include <linux/cpufreq.h> | |
| 20 | ||
| 21 | #include <mach/hardware.h> | |
| 22 | ||
| 23 | static struct cpufreq_driver ucv2_driver; | |
| 24 | ||
| 25 | /* make sure that only the "userspace" governor is run | |
| 26 | * -- anything else wouldn't make sense on this platform, anyway. | |
| 27 | */ | |
| 0e25246f | 28 | static int ucv2_verify_speed(struct cpufreq_policy *policy) |
| 64909882 G |
29 | { |
| 30 | if (policy->cpu) | |
| 31 | return -EINVAL; | |
| 32 | ||
| be49e346 | 33 | cpufreq_verify_within_cpu_limits(policy); |
| 64909882 G |
34 | return 0; |
| 35 | } | |
| 36 | ||
| 64909882 G |
37 | static int ucv2_target(struct cpufreq_policy *policy, |
| 38 | unsigned int target_freq, | |
| 39 | unsigned int relation) | |
| 40 | { | |
| 64909882 | 41 | struct cpufreq_freqs freqs; |
| ab1b1c4e | 42 | int ret; |
| 64909882 | 43 | |
| ab1b1c4e VK |
44 | freqs.old = policy->cur; |
| 45 | freqs.new = target_freq; | |
| 64909882 | 46 | |
| 8fec051e | 47 | cpufreq_freq_transition_begin(policy, &freqs); |
| b4ddad95 | 48 | ret = clk_set_rate(policy->clk, target_freq * 1000); |
| 8fec051e | 49 | cpufreq_freq_transition_end(policy, &freqs, ret); |
| 64909882 | 50 | |
| ab1b1c4e | 51 | return ret; |
| 64909882 G |
52 | } |
| 53 | ||
| 54 | static int __init ucv2_cpu_init(struct cpufreq_policy *policy) | |
| 55 | { | |
| 56 | if (policy->cpu != 0) | |
| 57 | return -EINVAL; | |
| 652ed95d | 58 | |
| 64909882 G |
59 | policy->min = policy->cpuinfo.min_freq = 250000; |
| 60 | policy->max = policy->cpuinfo.max_freq = 1000000; | |
| 61 | policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL; | |
| 652ed95d | 62 | policy->clk = clk_get(NULL, "MAIN_CLK"); |
| 8ab4e2b3 | 63 | return PTR_ERR_OR_ZERO(policy->clk); |
| 64909882 G |
64 | } |
| 65 | ||
| 66 | static struct cpufreq_driver ucv2_driver = { | |
| 67 | .flags = CPUFREQ_STICKY, | |
| 68 | .verify = ucv2_verify_speed, | |
| 69 | .target = ucv2_target, | |
| 652ed95d | 70 | .get = cpufreq_generic_get, |
| 64909882 G |
71 | .init = ucv2_cpu_init, |
| 72 | .name = "UniCore-II", | |
| 73 | }; | |
| 74 | ||
| 75 | static int __init ucv2_cpufreq_init(void) | |
| 76 | { | |
| 77 | return cpufreq_register_driver(&ucv2_driver); | |
| 78 | } | |
| 79 | ||
| 80 | arch_initcall(ucv2_cpufreq_init); |