^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) * Cpufreq driver for the loongson-2 processors
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * The 2E revision of loongson processor not support this feature.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * Copyright (C) 2006 - 2008 Lemote Inc. & Institute of Computing Technology
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Author: Yanhua, yanh@lemote.com
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) * This file is subject to the terms and conditions of the GNU General Public
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) * License. See the file "COPYING" in the main directory of this archive
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) * for more details.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/cpufreq.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <linux/err.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include <linux/sched.h> /* set_cpus_allowed() */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <linux/delay.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #include <asm/idle.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) #include <asm/mach-loongson2ef/loongson.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) static uint nowait;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) static void (*saved_cpu_wait) (void);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) static int loongson2_cpu_freq_notifier(struct notifier_block *nb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) unsigned long val, void *data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) static struct notifier_block loongson2_cpufreq_notifier_block = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) .notifier_call = loongson2_cpu_freq_notifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) static int loongson2_cpu_freq_notifier(struct notifier_block *nb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) unsigned long val, void *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) if (val == CPUFREQ_POSTCHANGE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) current_cpu_data.udelay_val = loops_per_jiffy;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) * Here we notify other drivers of the proposed change and the final change.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) static int loongson2_cpufreq_target(struct cpufreq_policy *policy,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) unsigned int index)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) unsigned int freq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) freq =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) ((cpu_clock_freq / 1000) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) loongson2_clockmod_table[index].driver_data) / 8;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) /* setting the cpu frequency */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) loongson2_cpu_set_rate(freq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) static int loongson2_cpufreq_cpu_init(struct cpufreq_policy *policy)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) unsigned long rate;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) rate = cpu_clock_freq / 1000;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) if (!rate)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) /* clock table init */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) for (i = 2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) (loongson2_clockmod_table[i].frequency != CPUFREQ_TABLE_END);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) loongson2_clockmod_table[i].frequency = (rate * i) / 8;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) ret = loongson2_cpu_set_rate(rate);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) cpufreq_generic_init(policy, &loongson2_clockmod_table[0], 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) static int loongson2_cpufreq_exit(struct cpufreq_policy *policy)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) static struct cpufreq_driver loongson2_cpufreq_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) .name = "loongson2",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) .init = loongson2_cpufreq_cpu_init,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) .verify = cpufreq_generic_frequency_table_verify,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) .target_index = loongson2_cpufreq_target,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) .get = cpufreq_generic_get,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) .exit = loongson2_cpufreq_exit,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) .attr = cpufreq_generic_attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) static const struct platform_device_id platform_device_ids[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) .name = "loongson2_cpufreq",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) {}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) MODULE_DEVICE_TABLE(platform, platform_device_ids);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) static struct platform_driver platform_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) .driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) .name = "loongson2_cpufreq",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) .id_table = platform_device_ids,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) * This is the simple version of Loongson-2 wait, Maybe we need do this in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) * interrupt disabled context.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) static DEFINE_SPINLOCK(loongson2_wait_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) static void loongson2_cpu_wait(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) unsigned long flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) u32 cpu_freq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) spin_lock_irqsave(&loongson2_wait_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) cpu_freq = readl(LOONGSON_CHIPCFG);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) /* Put CPU into wait mode */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) writel(readl(LOONGSON_CHIPCFG) & ~0x7, LOONGSON_CHIPCFG);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) /* Restore CPU state */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) writel(cpu_freq, LOONGSON_CHIPCFG);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) spin_unlock_irqrestore(&loongson2_wait_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) local_irq_enable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) static int __init cpufreq_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) /* Register platform stuff */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) ret = platform_driver_register(&platform_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) pr_info("Loongson-2F CPU frequency driver\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) cpufreq_register_notifier(&loongson2_cpufreq_notifier_block,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) CPUFREQ_TRANSITION_NOTIFIER);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) ret = cpufreq_register_driver(&loongson2_cpufreq_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) if (!ret && !nowait) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) saved_cpu_wait = cpu_wait;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) cpu_wait = loongson2_cpu_wait;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) static void __exit cpufreq_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) if (!nowait && saved_cpu_wait)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) cpu_wait = saved_cpu_wait;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) cpufreq_unregister_driver(&loongson2_cpufreq_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) cpufreq_unregister_notifier(&loongson2_cpufreq_notifier_block,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) CPUFREQ_TRANSITION_NOTIFIER);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) platform_driver_unregister(&platform_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) module_init(cpufreq_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) module_exit(cpufreq_exit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) module_param(nowait, uint, 0644);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) MODULE_PARM_DESC(nowait, "Disable Loongson-2F specific wait");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) MODULE_AUTHOR("Yanhua <yanh@lemote.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) MODULE_DESCRIPTION("cpufreq driver for Loongson2F");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) MODULE_LICENSE("GPL");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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