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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * cooling device driver that activates the processor throttling by4 * programming the TCC Offset register.5 * Copyright (c) 2021, Intel Corporation.6 */7#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt8 9#include <linux/device.h>10#include <linux/intel_tcc.h>11#include <linux/module.h>12#include <linux/thermal.h>13#include <asm/cpu_device_id.h>14 15#define TCC_PROGRAMMABLE BIT(30)16#define TCC_LOCKED BIT(31)17 18static struct thermal_cooling_device *tcc_cdev;19 20static int tcc_get_max_state(struct thermal_cooling_device *cdev, unsigned long21 *state)22{23 *state = intel_tcc_get_offset_mask();24 return 0;25}26 27static int tcc_get_cur_state(struct thermal_cooling_device *cdev, unsigned long28 *state)29{30 int offset = intel_tcc_get_offset(-1);31 32 if (offset < 0)33 return offset;34 35 *state = offset;36 return 0;37}38 39static int tcc_set_cur_state(struct thermal_cooling_device *cdev, unsigned long40 state)41{42 return intel_tcc_set_offset(-1, (int)state);43}44 45static const struct thermal_cooling_device_ops tcc_cooling_ops = {46 .get_max_state = tcc_get_max_state,47 .get_cur_state = tcc_get_cur_state,48 .set_cur_state = tcc_set_cur_state,49};50 51static const struct x86_cpu_id tcc_ids[] __initconst = {52 X86_MATCH_VFM(INTEL_SKYLAKE, NULL),53 X86_MATCH_VFM(INTEL_SKYLAKE_L, NULL),54 X86_MATCH_VFM(INTEL_KABYLAKE, NULL),55 X86_MATCH_VFM(INTEL_KABYLAKE_L, NULL),56 X86_MATCH_VFM(INTEL_ICELAKE, NULL),57 X86_MATCH_VFM(INTEL_ICELAKE_L, NULL),58 X86_MATCH_VFM(INTEL_TIGERLAKE, NULL),59 X86_MATCH_VFM(INTEL_TIGERLAKE_L, NULL),60 X86_MATCH_VFM(INTEL_COMETLAKE, NULL),61 X86_MATCH_VFM(INTEL_ALDERLAKE, NULL),62 X86_MATCH_VFM(INTEL_ALDERLAKE_L, NULL),63 X86_MATCH_VFM(INTEL_ATOM_GRACEMONT, NULL),64 X86_MATCH_VFM(INTEL_RAPTORLAKE, NULL),65 X86_MATCH_VFM(INTEL_RAPTORLAKE_P, NULL),66 X86_MATCH_VFM(INTEL_RAPTORLAKE_S, NULL),67 {}68};69 70MODULE_DEVICE_TABLE(x86cpu, tcc_ids);71 72static int __init tcc_cooling_init(void)73{74 int ret;75 u64 val;76 const struct x86_cpu_id *id;77 78 int err;79 80 id = x86_match_cpu(tcc_ids);81 if (!id)82 return -ENODEV;83 84 err = rdmsrl_safe(MSR_PLATFORM_INFO, &val);85 if (err)86 return err;87 88 if (!(val & TCC_PROGRAMMABLE))89 return -ENODEV;90 91 err = rdmsrl_safe(MSR_IA32_TEMPERATURE_TARGET, &val);92 if (err)93 return err;94 95 if (val & TCC_LOCKED) {96 pr_info("TCC Offset locked\n");97 return -ENODEV;98 }99 100 pr_info("Programmable TCC Offset detected\n");101 102 tcc_cdev =103 thermal_cooling_device_register("TCC Offset", NULL,104 &tcc_cooling_ops);105 if (IS_ERR(tcc_cdev)) {106 ret = PTR_ERR(tcc_cdev);107 return ret;108 }109 return 0;110}111 112module_init(tcc_cooling_init)113 114static void __exit tcc_cooling_exit(void)115{116 thermal_cooling_device_unregister(tcc_cdev);117}118 119module_exit(tcc_cooling_exit)120 121MODULE_IMPORT_NS(INTEL_TCC);122MODULE_DESCRIPTION("TCC offset cooling device Driver");123MODULE_AUTHOR("Zhang Rui <rui.zhang@intel.com>");124MODULE_LICENSE("GPL v2");125