1 // SPDX-License-Identifier: GPL-2.0-only
3 * cooling device driver that activates the processor throttling by
4 * programming the TCC Offset register.
5 * Copyright (c) 2021, Intel Corporation.
7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9 #include <linux/device.h>
10 #include <linux/module.h>
11 #include <linux/thermal.h>
12 #include <asm/cpu_device_id.h>
15 #define TCC_MASK (0x3fULL<<24)
16 #define TCC_PROGRAMMABLE BIT(30)
18 static struct thermal_cooling_device *tcc_cdev;
20 static int tcc_get_max_state(struct thermal_cooling_device *cdev, unsigned long
23 *state = TCC_MASK >> TCC_SHIFT;
27 static int tcc_offset_update(int tcc)
32 err = rdmsrl_safe(MSR_IA32_TEMPERATURE_TARGET, &val);
37 val |= tcc << TCC_SHIFT;
39 err = wrmsrl_safe(MSR_IA32_TEMPERATURE_TARGET, val);
46 static int tcc_get_cur_state(struct thermal_cooling_device *cdev, unsigned long
52 err = rdmsrl_safe(MSR_IA32_TEMPERATURE_TARGET, &val);
56 *state = (val & TCC_MASK) >> TCC_SHIFT;
60 static int tcc_set_cur_state(struct thermal_cooling_device *cdev, unsigned long
63 return tcc_offset_update(state);
66 static const struct thermal_cooling_device_ops tcc_cooling_ops = {
67 .get_max_state = tcc_get_max_state,
68 .get_cur_state = tcc_get_cur_state,
69 .set_cur_state = tcc_set_cur_state,
72 static const struct x86_cpu_id tcc_ids[] __initconst = {
73 X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE, NULL),
74 X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_L, NULL),
75 X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE, NULL),
76 X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE_L, NULL),
77 X86_MATCH_INTEL_FAM6_MODEL(ICELAKE, NULL),
78 X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_L, NULL),
79 X86_MATCH_INTEL_FAM6_MODEL(TIGERLAKE, NULL),
80 X86_MATCH_INTEL_FAM6_MODEL(TIGERLAKE_L, NULL),
81 X86_MATCH_INTEL_FAM6_MODEL(COMETLAKE, NULL),
85 MODULE_DEVICE_TABLE(x86cpu, tcc_ids);
87 static int __init tcc_cooling_init(void)
91 const struct x86_cpu_id *id;
95 id = x86_match_cpu(tcc_ids);
99 err = rdmsrl_safe(MSR_PLATFORM_INFO, &val);
103 if (!(val & TCC_PROGRAMMABLE))
106 pr_info("Programmable TCC Offset detected\n");
109 thermal_cooling_device_register("TCC Offset", NULL,
111 if (IS_ERR(tcc_cdev)) {
112 ret = PTR_ERR(tcc_cdev);
118 module_init(tcc_cooling_init)
120 static void __exit tcc_cooling_exit(void)
122 thermal_cooling_device_unregister(tcc_cdev);
125 module_exit(tcc_cooling_exit)
127 MODULE_DESCRIPTION("TCC offset cooling device Driver");
128 MODULE_AUTHOR("Zhang Rui <rui.zhang@intel.com>");
129 MODULE_LICENSE("GPL v2");