1 files changed, 243 insertions, 0 deletions
diff --git a/drivers/thermal/intel/int340x_thermal/platform_temperature_control.c b/drivers/thermal/intel/int340x_thermal/platform_temperature_control.c
new file mode 100644
index 000000000000..2d6504514893
--- /dev/null
+++ b/drivers/thermal/intel/int340x_thermal/platform_temperature_control.c
@@ -0,0 +1,243 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * processor thermal device platform temperature controls
+ * Copyright (c) 2025, Intel Corporation.
+ */
+
+/*
+ * Platform temperature controls hardware interface
+ *
+ * The hardware control interface is via MMIO offsets in the processor
+ * thermal device MMIO space. There are three instances of MMIO registers.
+ * All registers are 64 bit wide with RW access.
+ *
+ * Name: PLATFORM_TEMPERATURE_CONTROL
+ * Offsets: 0x5B20, 0x5B28, 0x5B30
+ *
+ *   Bits    Description
+ *   7:0     TARGET_TEMP : Target temperature limit to which the control
+ *           mechanism is regulating. Units: 0.5C.
+ *   8:8     ENABLE: Read current enable status of the feature or enable
+ *           feature.
+ *   11:9    GAIN: Sets the aggressiveness of control loop from 0 to 7
+ *           7 graceful, favors performance at the expense of temperature
+ *           overshoots
+ *           0 aggressive, favors tight regulation over performance
+ *   12:12   TEMPERATURE_OVERRIDE_EN
+ *           When set, hardware will use TEMPERATURE_OVERRIDE values instead
+ *           of reading from corresponding sensor.
+ *   15:13   RESERVED
+ *   23:16   MIN_PERFORMANCE_LEVEL: Minimum Performance level below which the
+ *           there will be no throttling. 0 - all levels of throttling allowed
+ *           including survivability actions. 255 - no throttling allowed.
+ *   31:24   TEMPERATURE_OVERRIDE: Allows SW to override the input temperature.
+ *           hardware will use this value instead of the sensor temperature.
+ *           Units: 0.5C.
+ *   63:32   RESERVED
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include "processor_thermal_device.h"
+
+struct mmio_reg {
+	int bits;
+	u16 mask;
+	u16 shift;
+	u16 units;
+};
+
+#define MAX_ATTR_GROUP_NAME_LEN	32
+#define PTC_MAX_ATTRS		3
+
+struct ptc_data {
+	u32 offset;
+	struct attribute_group ptc_attr_group;
+	struct attribute *ptc_attrs[PTC_MAX_ATTRS];
+	struct device_attribute temperature_target_attr;
+	struct device_attribute enable_attr;
+	char group_name[MAX_ATTR_GROUP_NAME_LEN];
+};
+
+static const struct mmio_reg ptc_mmio_regs[] = {
+	{ 8, 0xFF, 0, 500}, /* temperature_target, units 0.5C*/
+	{ 1, 0x01, 8, 0}, /* enable */
+	{ 3, 0x7, 9, 0}, /* gain */
+	{ 8, 0xFF, 16, 0}, /* min_performance_level */
+	{ 1, 0x1, 12, 0}, /* temperature_override_enable */
+	{ 8, 0xFF, 24, 500}, /* temperature_override, units 0.5C */
+};
+
+#define PTC_MAX_INSTANCES	3
+
+/* Unique offset for each PTC instance */
+static u32 ptc_offsets[PTC_MAX_INSTANCES] = {0x5B20, 0x5B28, 0x5B30};
+
+/* These will represent sysfs attribute names */
+static const char * const ptc_strings[] = {
+	"temperature_target",
+	"enable",
+	NULL
+};
+
+/* Lock to protect concurrent read/write and read-modify-write */
+static DEFINE_MUTEX(ptc_lock);
+
+static ssize_t ptc_mmio_show(struct ptc_data *data, struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct proc_thermal_device *proc_priv;
+	const struct mmio_reg *mmio_regs;
+	int ret, units;
+	u64 reg_val;
+
+	proc_priv = pci_get_drvdata(pdev);
+	mmio_regs = ptc_mmio_regs;
+	ret = match_string(ptc_strings, -1, attr->attr.name);
+	if (ret < 0)
+		return ret;
+
+	units = mmio_regs[ret].units;
+
+	guard(mutex)(&ptc_lock);
+
+	reg_val = readq((void __iomem *) (proc_priv->mmio_base + data->offset));
+	ret = (reg_val >> mmio_regs[ret].shift) & mmio_regs[ret].mask;
+	if (units)
+		ret *= units;
+
+	return sysfs_emit(buf, "%d\n", ret);
+}
+
+#define PTC_SHOW(suffix)\
+static ssize_t suffix##_show(struct device *dev,\
+			     struct device_attribute *attr,\
+			     char *buf)\
+{\
+	struct ptc_data *data = container_of(attr, struct ptc_data, suffix##_attr);\
+	return ptc_mmio_show(data, dev, attr, buf);\
+}
+
+static void ptc_mmio_write(struct pci_dev *pdev, u32 offset, int index, u32 value)
+{
+	struct proc_thermal_device *proc_priv;
+	u64 mask, reg_val;
+
+	proc_priv = pci_get_drvdata(pdev);
+
+	mask = GENMASK_ULL(ptc_mmio_regs[index].shift + ptc_mmio_regs[index].bits - 1,
+			   ptc_mmio_regs[index].shift);
+
+	guard(mutex)(&ptc_lock);
+
+	reg_val = readq((void __iomem *) (proc_priv->mmio_base + offset));
+	reg_val &= ~mask;
+	reg_val |= (value << ptc_mmio_regs[index].shift);
+	writeq(reg_val, (void __iomem *) (proc_priv->mmio_base + offset));
+}
+
+static int ptc_store(struct ptc_data *data, struct device *dev, struct device_attribute *attr,
+		     const char *buf,  size_t count)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	unsigned int input;
+	int ret;
+
+	ret = kstrtouint(buf, 10, &input);
+	if (ret)
+		return ret;
+
+	ret = match_string(ptc_strings, -1, attr->attr.name);
+	if (ret < 0)
+		return ret;
+
+	if (ptc_mmio_regs[ret].units)
+		input /= ptc_mmio_regs[ret].units;
+
+	if (input > ptc_mmio_regs[ret].mask)
+		return -EINVAL;
+
+	ptc_mmio_write(pdev, data->offset, ret, input);
+
+	return count;
+}
+
+#define PTC_STORE(suffix)\
+static ssize_t suffix##_store(struct device *dev,\
+			      struct device_attribute *attr,\
+			      const char *buf, size_t count)\
+{\
+	struct ptc_data *data = container_of(attr, struct ptc_data, suffix##_attr);\
+	return ptc_store(data, dev, attr, buf, count);\
+}
+
+PTC_SHOW(temperature_target);
+PTC_STORE(temperature_target);
+PTC_SHOW(enable);
+PTC_STORE(enable);
+
+#define ptc_init_attribute(_name)\
+	do {\
+		sysfs_attr_init(&data->_name##_attr.attr);\
+		data->_name##_attr.show = _name##_show;\
+		data->_name##_attr.store = _name##_store;\
+		data->_name##_attr.attr.name = #_name;\
+		data->_name##_attr.attr.mode = 0644;\
+	} while (0)
+
+static int ptc_create_groups(struct pci_dev *pdev, int instance, struct ptc_data *data)
+{
+	int ret, index = 0;
+
+	ptc_init_attribute(temperature_target);
+	ptc_init_attribute(enable);
+
+	data->ptc_attrs[index++] = &data->temperature_target_attr.attr;
+	data->ptc_attrs[index++] = &data->enable_attr.attr;
+	data->ptc_attrs[index] = NULL;
+
+	snprintf(data->group_name, MAX_ATTR_GROUP_NAME_LEN,
+		"ptc_%d_control", instance);
+	data->ptc_attr_group.name = data->group_name;
+	data->ptc_attr_group.attrs = data->ptc_attrs;
+
+	ret = sysfs_create_group(&pdev->dev.kobj, &data->ptc_attr_group);
+
+	return ret;
+}
+
+static struct ptc_data ptc_instance[PTC_MAX_INSTANCES];
+
+int proc_thermal_ptc_add(struct pci_dev *pdev, struct proc_thermal_device *proc_priv)
+{
+	if (proc_priv->mmio_feature_mask & PROC_THERMAL_FEATURE_PTC) {
+		int i;
+
+		for (i = 0; i < PTC_MAX_INSTANCES; i++) {
+			ptc_instance[i].offset = ptc_offsets[i];
+			ptc_create_groups(pdev, i, &ptc_instance[i]);
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(proc_thermal_ptc_add);
+
+void proc_thermal_ptc_remove(struct pci_dev *pdev)
+{
+	struct proc_thermal_device *proc_priv = pci_get_drvdata(pdev);
+
+	if (proc_priv->mmio_feature_mask & PROC_THERMAL_FEATURE_PTC) {
+		int i;
+
+		for (i = 0; i < PTC_MAX_INSTANCES; i++)
+			sysfs_remove_group(&pdev->dev.kobj, &ptc_instance[i].ptc_attr_group);
+	}
+}
+EXPORT_SYMBOL_GPL(proc_thermal_ptc_remove);
+
+MODULE_IMPORT_NS("INT340X_THERMAL");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Processor Thermal PTC Interface");