1 // SPDX-License-Identifier: GPL-2.0-only
3  * intel_tcc.c - Library for Intel TCC (thermal control circuitry) MSR access
12  * intel_tcc_get_tjmax() - returns the default TCC activation Temperature
22 	u32 low, high;  in intel_tcc_get_tjmax()  local
26 		err = rdmsr_safe(MSR_IA32_TEMPERATURE_TARGET, &low, &high);  in intel_tcc_get_tjmax()
28 		err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET, &low, &high);  in intel_tcc_get_tjmax()
32 	val = (low >> 16) & 0xff;  in intel_tcc_get_tjmax()
34 	return val ? val : -ENODATA;  in intel_tcc_get_tjmax()
39  * intel_tcc_get_offset() - returns the TCC Offset value to Tjmax
42  * Get the TCC offset value to Tjmax. The effective thermal throttling or TCC
43  * activation temperature equals "Tjmax" - "TCC Offset", in degrees C.
49 	u32 low, high;  in intel_tcc_get_offset()  local
53 		err = rdmsr_safe(MSR_IA32_TEMPERATURE_TARGET, &low, &high);  in intel_tcc_get_offset()
55 		err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET, &low, &high);  in intel_tcc_get_offset()
59 	return (low >> 24) & 0x3f;  in intel_tcc_get_offset()
64  * intel_tcc_set_offset() - set the TCC offset value to Tjmax
68  * Set the TCC Offset value to Tjmax. The effective thermal throttling or TCC
69  * activation temperature equals "Tjmax" - "TCC Offset", in degree C.
76 	u32 low, high;  in intel_tcc_set_offset()  local
80 		return -EINVAL;  in intel_tcc_set_offset()
83 		err = rdmsr_safe(MSR_IA32_TEMPERATURE_TARGET, &low, &high);  in intel_tcc_set_offset()
85 		err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET, &low, &high);  in intel_tcc_set_offset()
90 	if (low & BIT(31))  in intel_tcc_set_offset()
91 		return -EPERM;  in intel_tcc_set_offset()
93 	low &= ~(0x3f << 24);  in intel_tcc_set_offset()
94 	low |= offset << 24;  in intel_tcc_set_offset()
97 		return wrmsr_safe(MSR_IA32_TEMPERATURE_TARGET, low, high);  in intel_tcc_set_offset()
99 		return wrmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET, low, high);  in intel_tcc_set_offset()
104  * intel_tcc_get_temp() - returns the current temperature
106  * @temp: pointer to the memory for saving cpu temperature.
116 	u32 low, high;  in intel_tcc_get_temp()  local
125 		err = rdmsr_safe(msr, &low, &high);  in intel_tcc_get_temp()
127 		err = rdmsr_safe_on_cpu(cpu, msr, &low, &high);  in intel_tcc_get_temp()
132 	if (!(low & BIT(31)))  in intel_tcc_get_temp()
133 		return -ENODATA;  in intel_tcc_get_temp()
135 	*temp = tjmax - ((low >> 16) & 0x7f);  in intel_tcc_get_temp()