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From:   dinh.nguyen@linux.intel.com
To:     linux-hwmon@vger.kernel.org
Cc:     dinguyen@kernel.org, devicetree@vger.kernel.org,
        robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org,
        linux-kernel@vger.kernel.org, jdelvare@suse.com,
        linux@roeck-us.net, Dinh Nguyen <dinh.nguyen@linux.intel.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Subject: [PATCH 3/5] hwmon: (socfpga) Add hardware monitoring support on SoCFPGA platforms
Date:   Mon, 10 Apr 2023 10:33:12 -0500
Message-Id: <20230410153314.27127-3-dinh.nguyen@linux.intel.com>
In-Reply-To: <20230410153314.27127-1-dinh.nguyen@linux.intel.com>
References: <20230410153314.27127-1-dinh.nguyen@linux.intel.com>
MIME-Version: 1.0
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From: Dinh Nguyen <dinh.nguyen@linux.intel.com>

The driver supports 64-bit SoCFPGA platforms for temperature and voltage
reading using the platform's SDM(Secure Device Manager). The driver
also uses the Stratix10 Service layer driver.

This driver only supports OF SoCFPGA 64-bit platforms.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dinh Nguyen <dinh.nguyen@linux.intel.com>
---
 Documentation/hwmon/index.rst                 |   1 +
 Documentation/hwmon/socfpga-hwmon.rst         |  30 ++
 drivers/firmware/stratix10-svc.c              |  18 +-
 drivers/hwmon/Kconfig                         |  11 +
 drivers/hwmon/Makefile                        |   1 +
 drivers/hwmon/socfpga-hwmon.c                 | 406 ++++++++++++++++++
 include/linux/firmware/intel/stratix10-smc.h  |  34 ++
 .../firmware/intel/stratix10-svc-client.h     |   6 +
 8 files changed, 506 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/hwmon/socfpga-hwmon.rst
 create mode 100644 drivers/hwmon/socfpga-hwmon.c

diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
index f1fe75f596a5..9db4e1537481 100644
--- a/Documentation/hwmon/index.rst
+++ b/Documentation/hwmon/index.rst
@@ -196,6 +196,7 @@ Hardware Monitoring Kernel Drivers
    smsc47b397
    smsc47m192
    smsc47m1
+   socfpga-hwmon
    sparx5-temp
    stpddc60
    sy7636a-hwmon
diff --git a/Documentation/hwmon/socfpga-hwmon.rst b/Documentation/hwmon/socfpga-hwmon.rst
new file mode 100644
index 000000000000..f6565c83cf40
--- /dev/null
+++ b/Documentation/hwmon/socfpga-hwmon.rst
@@ -0,0 +1,30 @@
+.. SPDX-License-Identifier: GPL-2.0-only
+
+Kernel driver socfpga-hwmon
+===========================
+
+Supported chips:
+
+ * Intel Stratix10
+ * Intel Agilex
+ * Intel N5X
+
+Author: Dinh Nguyen <dinh.nguyen@linux.intel.com>
+
+Description
+-----------
+
+This driver supports hardware monitoring for 64-Bit SoCFPGA and eASIC devices
+based around the Secure Device Manager and Stratix 10 Service layer.
+
+The following sensor types are supported:
+
+  * temperature
+  * voltage
+
+Usage Notes
+-----------
+
+The driver relies on a device tree node to enumerate support present on the
+specific device. See Documentation/devicetree/bindings/hwmon/intel,socfpga-hwmon.yaml
+for details of the device-tree node.
diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
index bde1f543f529..cc1b8b441c37 100644
--- a/drivers/firmware/stratix10-svc.c
+++ b/drivers/firmware/stratix10-svc.c
@@ -340,6 +340,8 @@ static void svc_thread_recv_status_ok(struct stratix10_svc_data *p_data,
 	case COMMAND_RSU_MAX_RETRY:
 	case COMMAND_RSU_DCMF_STATUS:
 	case COMMAND_FIRMWARE_VERSION:
+	case COMMAND_HWMON_READTEMP:
+	case COMMAND_HWMON_READVOLT:
 		cb_data->status = BIT(SVC_STATUS_OK);
 		cb_data->kaddr1 = &res.a1;
 		break;
@@ -517,7 +519,17 @@ static int svc_normal_to_secure_thread(void *data)
 			a1 = (unsigned long)pdata->paddr;
 			a2 = 0;
 			break;
-
+		/* for HWMON */
+		case COMMAND_HWMON_READTEMP:
+			a0 = INTEL_SIP_SMC_HWMON_READTEMP;
+			a1 = pdata->arg[0];
+			a2 = 0;
+			break;
+		case COMMAND_HWMON_READVOLT:
+			a0 = INTEL_SIP_SMC_HWMON_READVOLT;
+			a1 = pdata->arg[0];
+			a2 = 0;
+			break;
 		/* for polling */
 		case COMMAND_POLL_SERVICE_STATUS:
 			a0 = INTEL_SIP_SMC_SERVICE_COMPLETED;
@@ -1182,6 +1194,10 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
 	chans[2].name = SVC_CLIENT_FCS;
 	spin_lock_init(&chans[2].lock);
 
+	chans[3].ctrl = controller;
+	chans[3].name = SVC_CLIENT_HWMON;
+	spin_lock_init(&chans[3].lock);
+
 	list_add_tail(&controller->node, &svc_ctrl);
 	platform_set_drvdata(pdev, controller);
 
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 5b3b76477b0e..c7c978acfece 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1875,6 +1875,17 @@ config SENSORS_SMSC47M192
 	  This driver can also be built as a module. If so, the module
 	  will be called smsc47m192.
 
+config SENSORS_SOCFPGA
+	tristate "SoCFPGA Hardware monitoring features"
+	depends on INTEL_STRATIX10_SERVICE
+	depends on OF || COMPILE_TEST
+	help
+	  If you say yes here you get support for the temperature and
+	  voltage sensors of 64-bit SoCFPGA devices.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called socfpga-hwmon.
+
 config SENSORS_SMSC47B397
 	tristate "SMSC LPC47B397-NC"
 	depends on !PPC
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 88712b5031c8..c04c0b2578a4 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -193,6 +193,7 @@ obj-$(CONFIG_SENSORS_SMPRO)	+= smpro-hwmon.o
 obj-$(CONFIG_SENSORS_SMSC47B397)+= smsc47b397.o
 obj-$(CONFIG_SENSORS_SMSC47M1)	+= smsc47m1.o
 obj-$(CONFIG_SENSORS_SMSC47M192)+= smsc47m192.o
+obj-$(CONFIG_SENSORS_SOCFPGA)	+= socfpga-hwmon.o
 obj-$(CONFIG_SENSORS_SPARX5)	+= sparx5-temp.o
 obj-$(CONFIG_SENSORS_STTS751)	+= stts751.o
 obj-$(CONFIG_SENSORS_SY7636A)	+= sy7636a-hwmon.o
diff --git a/drivers/hwmon/socfpga-hwmon.c b/drivers/hwmon/socfpga-hwmon.c
new file mode 100644
index 000000000000..636e6e269578
--- /dev/null
+++ b/drivers/hwmon/socfpga-hwmon.c
@@ -0,0 +1,406 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * SoCFPGA hardware monitoring features
+ *
+ * Copyright (c) 2023 Intel Corporation. All rights reserved
+ */
+#include <linux/arm-smccc.h>
+#include <linux/hwmon.h>
+#include <linux/firmware/intel/stratix10-svc-client.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/units.h>
+
+#define HWMON_TIMEOUT	msecs_to_jiffies(SVC_HWMON_REQUEST_TIMEOUT_MS)
+
+/*
+ * When bit 31 is set, an error condition has been detected in the
+ * temperature sensor.
+ */
+#define ETEMP_ERROR			BIT(31)
+/*
+ * Selected temperature sensor channel is currently inactive.
+ * Ensure that the tile where the TSD is located is actively in use.
+ */
+#define ETEMP_INACTIVE			0x0
+/*
+ * Selected temperature sensor channel returned a value that is not the
+ * latest reading. Try retrieve the temperature reading again.
+ */
+#define ETEMP_TOO_OLD			0x1
+/*
+ * Selected temperature sensor channel is invalid for the device. Ignore
+ * the returned data because the temperature sensor channel location is
+ * invalid.
+ */
+#define ETEMP_NOT_PRESENT		0x2
+/*
+ * System is corrupted or failed to respond.
+ */
+#define ETEMP_TIMEOUT			0x3
+#define ETEMP_CORRUPT			0x4
+/*
+ * Communication mechanism is busy.
+ */
+#define ETEMP_BUSY			0x5
+/*
+ * System is corrupted or failed to respond.
+ */
+#define ETEMP_NOT_INITIALIZED		0xFF
+
+#define SOCFPGA_HWMON_MAXSENSORS	16
+
+/**
+ * struct socfpga_hwmon_chan - channel input parameters.
+ * @n : Number of channels.
+ * @value: value read from the chip.
+ * @names: names array from DTS labels.
+ * @chan: channel array.
+ *
+ * The structure represents either the voltage or temperature information
+ * for the hwmon channels.
+ */
+struct socfpga_hwmon_chan {
+	unsigned int n;
+	int value;
+	const char *names[SOCFPGA_HWMON_MAXSENSORS];
+	u32 chan[SOCFPGA_HWMON_MAXSENSORS];
+};
+
+struct socfpga_hwmon_priv {
+	struct stratix10_svc_client client;
+	struct stratix10_svc_client_msg msg;
+	struct stratix10_svc_chan *chan;
+	struct completion completion;
+	struct mutex lock;
+	struct socfpga_hwmon_chan temperature;
+	struct socfpga_hwmon_chan voltage;
+};
+
+enum hwmon_type_op {
+	SOCFPGA_HWMON_TYPE_TEMP,
+	SOCFPGA_HWMON_TYPE_VOLT,
+	SOCFPGA_HWMON_TYPE_MAX
+};
+
+static const char *const hwmon_types_str[] = { "temperature", "voltage" };
+
+static umode_t socfpga_is_visible(const void *dev,
+				  enum hwmon_sensor_types type,
+				  u32 attr, int chan)
+{
+	switch (type) {
+	case hwmon_temp:
+	case hwmon_in:
+		return 0444;
+	default:
+		return 0;
+	}
+}
+
+static void socfpga_smc_callback(struct stratix10_svc_client *client,
+					  struct stratix10_svc_cb_data *data)
+{
+	struct socfpga_hwmon_priv *priv = client->priv;
+	struct arm_smccc_res *res = data->kaddr1;
+
+	if (data->status == BIT(SVC_STATUS_OK))	{
+		if (priv->msg.command == COMMAND_HWMON_READTEMP)
+			priv->temperature.value = res->a0;
+		else
+			priv->voltage.value = res->a0;
+	} else
+		dev_err(client->dev, "%s returned 0x%lX\n", __func__, res->a0);
+
+	complete(&priv->completion);
+}
+
+static int socfpga_hwmon_send(struct socfpga_hwmon_priv *priv)
+{
+	int ret;
+
+	priv->client.receive_cb = socfpga_smc_callback;
+
+	ret = stratix10_svc_send(priv->chan, &priv->msg);
+	if (ret < 0)
+		return ret;
+
+	if (!wait_for_completion_timeout(&priv->completion, HWMON_TIMEOUT)) {
+		dev_err(priv->client.dev, "SMC call timeout!\n");
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static int socfpga_hwmon_err_to_errno(struct socfpga_hwmon_priv *priv)
+{
+	int value = priv->temperature.value;
+
+	if (!(value & ETEMP_ERROR))
+		return 0;
+
+	dev_err(priv->client.dev, "temperature sensor code 0x%08x\n", value);
+
+	value &= ~ETEMP_ERROR;
+	switch (value) {
+	case ETEMP_NOT_PRESENT:
+		return -ENOENT;
+	case ETEMP_CORRUPT:
+	case ETEMP_NOT_INITIALIZED:
+		return -ENODATA;
+	case ETEMP_BUSY:
+		return -EBUSY;
+	case ETEMP_INACTIVE:
+	case ETEMP_TIMEOUT:
+	case ETEMP_TOO_OLD:
+		return -EAGAIN;
+	default:
+		/* Unknown error */
+		return -EINVAL;
+	}
+}
+
+static int socfpga_read(struct device *dev, enum hwmon_sensor_types type,
+			u32 attr, int chan, long *val)
+{
+	struct socfpga_hwmon_priv *priv = dev_get_drvdata(dev);
+	int ret;
+
+	mutex_lock(&priv->lock);
+	reinit_completion(&priv->completion);
+
+	switch (type) {
+	case hwmon_temp:
+		priv->msg.arg[0] = BIT_ULL(priv->temperature.chan[chan]);
+		priv->msg.command = COMMAND_HWMON_READTEMP;
+		if (socfpga_hwmon_send(priv))
+			goto status_done;
+
+		ret = socfpga_hwmon_err_to_errno(priv);
+		if (ret)
+			break;
+		/*
+		 * The Temperature Sensor IP core returns the Celsius
+		 * temperature value in signed 32-bit fixed point binary
+		 * format, with eight bits below binary point.
+		 */
+		*val = (priv->temperature.value * MILLIDEGREE_PER_DEGREE) / 256;
+		break;
+	case hwmon_in: /* Read voltage */
+		priv->msg.arg[0] = BIT_ULL(priv->voltage.chan[chan]);
+		priv->msg.command = COMMAND_HWMON_READVOLT;
+		if (socfpga_hwmon_send(priv))
+			goto status_done;
+
+		/*
+		 * The Voltage Sensor IP core returns the sampled voltage
+		 * in unsigned 32-bit fixed point binary format, with 16 bits
+		 * below binary point.
+		 */
+		*val = (priv->voltage.value * MILLIVOLT_PER_VOLT) / 65536;
+		break;
+	default:
+		ret = -EOPNOTSUPP;
+		break;
+	}
+
+status_done:
+	stratix10_svc_done(priv->chan);
+	mutex_unlock(&priv->lock);
+	return ret;
+}
+
+static int socfpga_read_string(struct device *dev,
+			       enum hwmon_sensor_types type, u32 attr,
+			       int chan, const char **str)
+{
+	struct socfpga_hwmon_priv *priv = dev_get_drvdata(dev);
+
+	switch (type) {
+	case hwmon_in:
+		*str = priv->voltage.names[chan];
+		return 0;
+	case hwmon_temp:
+		*str = priv->temperature.names[chan];
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static const struct hwmon_ops socfpga_ops = {
+	.is_visible = socfpga_is_visible,
+	.read = socfpga_read,
+	.read_string = socfpga_read_string,
+};
+
+static const struct hwmon_channel_info *socfpga_info[] = {
+	HWMON_CHANNEL_INFO(temp,
+		HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL,
+		HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL,
+		HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL,
+		HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL,
+		HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL,
+		HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL,
+		HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL,
+		HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL),
+	HWMON_CHANNEL_INFO(in,
+		HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL,
+		HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL,
+		HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL,
+		HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL,
+		HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL,
+		HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL,
+		HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL,
+		HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL),
+	NULL
+};
+
+static const struct hwmon_chip_info socfpga_chip_info = {
+	.ops = &socfpga_ops,
+	.info = socfpga_info,
+};
+
+static int socfpga_add_channel(struct device *dev,  const char *type,
+				u32 val, const char *label,
+				struct socfpga_hwmon_priv *priv)
+{
+	int type_index;
+	struct socfpga_hwmon_chan *p;
+
+	type_index = match_string(hwmon_types_str, ARRAY_SIZE(hwmon_types_str), type);
+	switch (type_index) {
+	case SOCFPGA_HWMON_TYPE_TEMP:
+		p = &priv->temperature;
+		break;
+	case SOCFPGA_HWMON_TYPE_VOLT:
+		p = &priv->voltage;
+		break;
+	default:
+		return -ENODATA;
+	}
+	if (p->n >= SOCFPGA_HWMON_MAXSENSORS)
+		return -ENOSPC;
+
+	p->names[p->n] = label;
+	p->chan[p->n] = val;
+	p->n++;
+
+	return 0;
+}
+
+static int socfpga_probe_child_from_dt(struct device *dev,
+				       struct device_node *child,
+				       struct socfpga_hwmon_priv *priv)
+{
+	struct device_node *grandchild;
+	const char *label;
+	const char *type;
+	u32 val;
+	int ret;
+
+	if (of_property_read_string(child, "name", &type))
+		return dev_err_probe(dev, -EINVAL, "No type for %pOF\n", child);
+
+	for_each_child_of_node(child, grandchild) {
+		ret = of_property_read_u32(grandchild, "reg", &val);
+		if (ret)
+			return dev_err_probe(dev, ret, "missing reg property of %pOF\n",
+					     grandchild);
+
+		ret = of_property_read_string(grandchild, "label", &label);
+		if (ret)
+			return dev_err_probe(dev, ret, "missing label propoerty of %pOF\n",
+					     grandchild);
+		ret = socfpga_add_channel(dev, type, val, label, priv);
+		if (ret == -ENOSPC)
+			return dev_err_probe(dev, ret, "too many channels, only %d supported\n",
+					     SOCFPGA_HWMON_MAXSENSORS);
+	}
+	return 0;
+}
+
+static int socfpga_probe_from_dt(struct device *dev,
+				 struct socfpga_hwmon_priv *priv)
+{
+	const struct device_node *np = dev->of_node;
+	struct device_node *child;
+	int ret = 0;
+
+	for_each_child_of_node(np, child) {
+		ret = socfpga_probe_child_from_dt(dev, child, priv);
+		if (ret)
+			break;
+	}
+	of_node_put(child);
+
+	return ret;
+}
+
+static int socfpga_hwmon_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device *hwmon_dev;
+	struct socfpga_hwmon_priv *priv;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->client.dev = dev;
+	priv->client.priv = priv;
+
+	ret = socfpga_probe_from_dt(dev, priv);
+	if (ret)
+		return dev_err_probe(dev, ret, "Unable to probe from device tree\n");
+
+	mutex_init(&priv->lock);
+	init_completion(&priv->completion);
+	hwmon_dev = devm_hwmon_device_register_with_info(dev, "socfpgahwmon",
+							 priv,
+							 &socfpga_chip_info,
+							 NULL);
+	if (IS_ERR(hwmon_dev))
+		return PTR_ERR(hwmon_dev);
+
+	priv->chan = stratix10_svc_request_channel_byname(&priv->client,
+					SVC_CLIENT_HWMON);
+	if (IS_ERR(priv->chan))
+		return dev_err_probe(dev, PTR_ERR(priv->chan),
+				     "couldn't get service channel %s\n",
+				     SVC_CLIENT_RSU);
+
+	platform_set_drvdata(pdev, priv);
+
+	return 0;
+}
+
+static int socfpga_hwmon_remove(struct platform_device *pdev)
+{
+	struct socfpga_hwmon_priv *priv = platform_get_drvdata(pdev);
+
+	stratix10_svc_free_channel(priv->chan);
+	return 0;
+}
+
+static const struct of_device_id socfpga_of_match[] = {
+	{ .compatible = "intel,socfpga-hwmon" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, socfpga_of_match);
+
+static struct platform_driver socfpga_hwmon_driver = {
+	.driver = {
+		.name = "socfpga-hwmon",
+		.of_match_table = socfpga_of_match,
+	},
+	.probe = socfpga_hwmon_probe,
+	.remove = socfpga_hwmon_remove,
+};
+module_platform_driver(socfpga_hwmon_driver);
+
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION("SoCFPGA hardware monitoring features");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/firmware/intel/stratix10-smc.h b/include/linux/firmware/intel/stratix10-smc.h
index a718f853d457..b944ec4b2b2f 100644
--- a/include/linux/firmware/intel/stratix10-smc.h
+++ b/include/linux/firmware/intel/stratix10-smc.h
@@ -595,4 +595,38 @@ INTEL_SIP_SMC_FAST_CALL_VAL(INTEL_SIP_SMC_FUNCID_FPGA_CONFIG_COMPLETED_WRITE)
 #define INTEL_SIP_SMC_FCS_GET_PROVISION_DATA \
 	INTEL_SIP_SMC_FAST_CALL_VAL(INTEL_SIP_SMC_FUNCID_FCS_GET_PROVISION_DATA)
 
+/**
+ * Request INTEL_SIP_SMC_HWMON_READTEMP
+ * Sync call to request temperature
+ *
+ * Call register usage:
+ * a0 Temperature Channel
+ * a1-a7 not used
+ *
+ * Return status
+ * a0 INTEL_SIP_SMC_STATUS_OK
+ * a1 Temperature Value
+ * a2-a3 not used
+ */
+#define INTEL_SIP_SMC_FUNCID_HWMON_READTEMP 32
+#define INTEL_SIP_SMC_HWMON_READTEMP \
+	INTEL_SIP_SMC_FAST_CALL_VAL(INTEL_SIP_SMC_FUNCID_HWMON_READTEMP)
+
+/**
+ * Request INTEL_SIP_SMC_HWMON_READVOLT
+ * Sync call to request voltage
+ *
+ * Call register usage:
+ * a0 Voltage Channel
+ * a1-a7 not used
+ *
+ * Return status
+ * a0 INTEL_SIP_SMC_STATUS_OK
+ * a1 Voltage Value
+ * a2-a3 not used
+ */
+#define INTEL_SIP_SMC_FUNCID_HWMON_READVOLT 33
+#define INTEL_SIP_SMC_HWMON_READVOLT \
+	INTEL_SIP_SMC_FAST_CALL_VAL(INTEL_SIP_SMC_FUNCID_HWMON_READVOLT)
+
 #endif
diff --git a/include/linux/firmware/intel/stratix10-svc-client.h b/include/linux/firmware/intel/stratix10-svc-client.h
index 0c16037fd08d..343970dcc2d2 100644
--- a/include/linux/firmware/intel/stratix10-svc-client.h
+++ b/include/linux/firmware/intel/stratix10-svc-client.h
@@ -11,10 +11,12 @@
  *
  * fpga: for FPGA configuration
  * rsu: for remote status update
+ * hwmon: for hardware monitoring (voltage and temperature)
  */
 #define SVC_CLIENT_FPGA			"fpga"
 #define SVC_CLIENT_RSU			"rsu"
 #define SVC_CLIENT_FCS			"fcs"
+#define SVC_CLIENT_HWMON		"hwmon"
 
 /*
  * Status of the sent command, in bit number
@@ -70,6 +72,7 @@
 #define SVC_RSU_REQUEST_TIMEOUT_MS              300
 #define SVC_FCS_REQUEST_TIMEOUT_MS		2000
 #define SVC_COMPLETED_TIMEOUT_MS		30000
+#define SVC_HWMON_REQUEST_TIMEOUT_MS		300
 
 struct stratix10_svc_chan;
 
@@ -164,6 +167,9 @@ enum stratix10_svc_command_code {
 	COMMAND_FCS_RANDOM_NUMBER_GEN,
 	/* for general status poll */
 	COMMAND_POLL_SERVICE_STATUS = 40,
+	/* for HWMON */
+	COMMAND_HWMON_READTEMP,
+	COMMAND_HWMON_READVOLT,
 	/* Non-mailbox SMC Call */
 	COMMAND_SMC_SVC_VERSION = 200,
 };
-- 
2.40.0