1 files changed, 129 insertions, 0 deletions
diff --git a/drivers/thermal/intel/intel_tcc_cooling.c b/drivers/thermal/intel/intel_tcc_cooling.c
new file mode 100644
index 000000000000..8ec10d55d421
--- /dev/null
+++ b/drivers/thermal/intel/intel_tcc_cooling.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * cooling device driver that activates the processor throttling by
+ * programming the TCC Offset register.
+ * Copyright (c) 2021, Intel Corporation.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/thermal.h>
+#include <asm/cpu_device_id.h>
+
+#define TCC_SHIFT 24
+#define TCC_MASK	(0x3fULL<<24)
+#define TCC_PROGRAMMABLE	BIT(30)
+
+static struct thermal_cooling_device *tcc_cdev;
+
+static int tcc_get_max_state(struct thermal_cooling_device *cdev, unsigned long
+			     *state)
+{
+	*state = TCC_MASK >> TCC_SHIFT;
+	return 0;
+}
+
+static int tcc_offset_update(int tcc)
+{
+	u64 val;
+	int err;
+
+	err = rdmsrl_safe(MSR_IA32_TEMPERATURE_TARGET, &val);
+	if (err)
+		return err;
+
+	val &= ~TCC_MASK;
+	val |= tcc << TCC_SHIFT;
+
+	err = wrmsrl_safe(MSR_IA32_TEMPERATURE_TARGET, val);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static int tcc_get_cur_state(struct thermal_cooling_device *cdev, unsigned long
+			     *state)
+{
+	u64 val;
+	int err;
+
+	err = rdmsrl_safe(MSR_IA32_TEMPERATURE_TARGET, &val);
+	if (err)
+		return err;
+
+	*state = (val & TCC_MASK) >> TCC_SHIFT;
+	return 0;
+}
+
+static int tcc_set_cur_state(struct thermal_cooling_device *cdev, unsigned long
+			     state)
+{
+	return tcc_offset_update(state);
+}
+
+static const struct thermal_cooling_device_ops tcc_cooling_ops = {
+	.get_max_state = tcc_get_max_state,
+	.get_cur_state = tcc_get_cur_state,
+	.set_cur_state = tcc_set_cur_state,
+};
+
+static const struct x86_cpu_id tcc_ids[] __initconst = {
+	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE, NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_L, NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE, NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE_L, NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE, NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_L, NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(TIGERLAKE, NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(TIGERLAKE_L, NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(COMETLAKE, NULL),
+	{}
+};
+
+MODULE_DEVICE_TABLE(x86cpu, tcc_ids);
+
+static int __init tcc_cooling_init(void)
+{
+	int ret;
+	u64 val;
+	const struct x86_cpu_id *id;
+
+	int err;
+
+	id = x86_match_cpu(tcc_ids);
+	if (!id)
+		return -ENODEV;
+
+	err = rdmsrl_safe(MSR_PLATFORM_INFO, &val);
+	if (err)
+		return err;
+
+	if (!(val & TCC_PROGRAMMABLE))
+		return -ENODEV;
+
+	pr_info("Programmable TCC Offset detected\n");
+
+	tcc_cdev =
+	    thermal_cooling_device_register("TCC Offset", NULL,
+					    &tcc_cooling_ops);
+	if (IS_ERR(tcc_cdev)) {
+		ret = PTR_ERR(tcc_cdev);
+		return ret;
+	}
+	return 0;
+}
+
+module_init(tcc_cooling_init)
+
+static void __exit tcc_cooling_exit(void)
+{
+	thermal_cooling_device_unregister(tcc_cdev);
+}
+
+module_exit(tcc_cooling_exit)
+
+MODULE_DESCRIPTION("TCC offset cooling device Driver");
+MODULE_AUTHOR("Zhang Rui <rui.zhang@intel.com>");
+MODULE_LICENSE("GPL v2");