[PATCH 4/4] thermal: int340x: processor_thermal: Add mailbox driver

From: Srinivas Pandruvada
Date: Thu Nov 26 2020 - 12:19:03 EST


Added processor thermal device mail box interface for workload hints
setting. These hints will give indication to hardware to better manage
power and thermals. The supported hints are:
idle
semi_active
burusty
sustained
battery_life

For example when the system is on battery, the hardware can be less
aggressive in power ramp up.

This will create an attribute group at
/sys/bus/pci/devices/0000:00:04.0/workload_request

This folder contains two attributes:
workload_available_types : (RO): This shows available workload types
workload_type: (RW) : Allows to set and get current workload type
setting

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
---
.../thermal/intel/int340x_thermal/Makefile | 1 +
.../processor_thermal_device.c | 17 +-
.../processor_thermal_device.h | 4 +
.../int340x_thermal/processor_thermal_mbox.c | 212 ++++++++++++++++++
4 files changed, 232 insertions(+), 2 deletions(-)
create mode 100644 drivers/thermal/intel/int340x_thermal/processor_thermal_mbox.c

diff --git a/drivers/thermal/intel/int340x_thermal/Makefile b/drivers/thermal/intel/int340x_thermal/Makefile
index f4e2eb7d9606..38a2731e503c 100644
--- a/drivers/thermal/intel/int340x_thermal/Makefile
+++ b/drivers/thermal/intel/int340x_thermal/Makefile
@@ -6,5 +6,6 @@ obj-$(CONFIG_INT340X_THERMAL) += int3403_thermal.o
obj-$(CONFIG_INT340X_THERMAL) += processor_thermal_device.o
obj-$(CONFIG_PROC_THERMAL_MMIO_RAPL) += processor_thermal_rapl.o
obj-$(CONFIG_INT340X_THERMAL) += processor_thermal_rfim.o
+obj-$(CONFIG_INT340X_THERMAL) += processor_thermal_mbox.o
obj-$(CONFIG_INT3406_THERMAL) += int3406_thermal.o
obj-$(CONFIG_ACPI_THERMAL_REL) += acpi_thermal_rel.o
diff --git a/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c b/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
index b6a7358b989d..9e6f2a895a23 100644
--- a/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
+++ b/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
@@ -454,8 +454,18 @@ static int proc_thermal_mmio_add(struct pci_dev *pdev,
}
}

+ if (feature_mask & PROC_THERMAL_FEATURE_MBOX) {
+ ret = proc_thermal_mbox_add(pdev, proc_priv);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to add MBOX interface\n");
+ goto err_rem_rfim;
+ }
+ }
+
return 0;

+err_rem_rfim:
+ proc_thermal_rfim_remove(pdev);
err_rem_rapl:
proc_thermal_rapl_remove();

@@ -472,6 +482,9 @@ static void proc_thermal_mmio_remove(struct pci_dev *pdev)
if (proc_priv->mmio_feature_mask & PROC_THERMAL_FEATURE_FIVR ||
proc_priv->mmio_feature_mask & PROC_THERMAL_FEATURE_DVFS)
proc_thermal_rfim_remove(pdev);
+
+ if (proc_priv->mmio_feature_mask & PROC_THERMAL_FEATURE_MBOX)
+ proc_thermal_mbox_remove(pdev);
}

static int proc_thermal_pci_probe(struct pci_dev *pdev,
@@ -583,7 +596,7 @@ static int proc_thermal_resume(struct device *dev)
static SIMPLE_DEV_PM_OPS(proc_thermal_pm, NULL, proc_thermal_resume);

static const struct pci_device_id proc_thermal_pci_ids[] = {
- { PCI_DEVICE_DATA(INTEL, ADL_THERMAL, PROC_THERMAL_FEATURE_RAPL | PROC_THERMAL_FEATURE_FIVR | PROC_THERMAL_FEATURE_DVFS) },
+ { PCI_DEVICE_DATA(INTEL, ADL_THERMAL, PROC_THERMAL_FEATURE_RAPL | PROC_THERMAL_FEATURE_FIVR | PROC_THERMAL_FEATURE_DVFS | PROC_THERMAL_FEATURE_MBOX) },
{ PCI_DEVICE_DATA(INTEL, BDW_THERMAL, 0) },
{ PCI_DEVICE_DATA(INTEL, BSW_THERMAL, 0) },
{ PCI_DEVICE_DATA(INTEL, BXT0_THERMAL, 0) },
@@ -597,7 +610,7 @@ static const struct pci_device_id proc_thermal_pci_ids[] = {
{ PCI_DEVICE_DATA(INTEL, ICL_THERMAL, PROC_THERMAL_FEATURE_RAPL) },
{ PCI_DEVICE_DATA(INTEL, JSL_THERMAL, 0) },
{ PCI_DEVICE_DATA(INTEL, SKL_THERMAL, PROC_THERMAL_FEATURE_RAPL) },
- { PCI_DEVICE_DATA(INTEL, TGL_THERMAL, PROC_THERMAL_FEATURE_RAPL | PROC_THERMAL_FEATURE_FIVR) },
+ { PCI_DEVICE_DATA(INTEL, TGL_THERMAL, PROC_THERMAL_FEATURE_RAPL | PROC_THERMAL_FEATURE_FIVR | PROC_THERMAL_FEATURE_MBOX) },
{ },
};

diff --git a/drivers/thermal/intel/int340x_thermal/processor_thermal_device.h b/drivers/thermal/intel/int340x_thermal/processor_thermal_device.h
index 4bbb88f6b4a7..b9ed64561aaf 100644
--- a/drivers/thermal/intel/int340x_thermal/processor_thermal_device.h
+++ b/drivers/thermal/intel/int340x_thermal/processor_thermal_device.h
@@ -56,6 +56,7 @@ struct rapl_mmio_regs {
#define PROC_THERMAL_FEATURE_RAPL 0x01
#define PROC_THERMAL_FEATURE_FIVR 0x02
#define PROC_THERMAL_FEATURE_DVFS 0x04
+#define PROC_THERMAL_FEATURE_MBOX 0x08

#if IS_ENABLED(CONFIG_PROC_THERMAL_MMIO_RAPL)
int proc_thermal_rapl_add(struct pci_dev *pdev, struct proc_thermal_device *proc_priv);
@@ -75,4 +76,7 @@ static void __maybe_unused proc_thermal_rapl_remove(void)
int proc_thermal_rfim_add(struct pci_dev *pdev, struct proc_thermal_device *proc_priv);
void proc_thermal_rfim_remove(struct pci_dev *pdev);

+int proc_thermal_mbox_add(struct pci_dev *pdev, struct proc_thermal_device *proc_priv);
+void proc_thermal_mbox_remove(struct pci_dev *pdev);
+
#endif
diff --git a/drivers/thermal/intel/int340x_thermal/processor_thermal_mbox.c b/drivers/thermal/intel/int340x_thermal/processor_thermal_mbox.c
new file mode 100644
index 000000000000..2c105fed2d7b
--- /dev/null
+++ b/drivers/thermal/intel/int340x_thermal/processor_thermal_mbox.c
@@ -0,0 +1,212 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * processor thermal device mailbox driver for Workload type hints
+ * Copyright (c) 2020, Intel Corporation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include "processor_thermal_device.h"
+
+#define MBOX_CMD_WORKLOAD_TYPE_READ 0x0E
+#define MBOX_CMD_WORKLOAD_TYPE_WRITE 0x0F
+
+#define MBOX_OFFSET_DATA 0x5810
+#define MBOX_OFFSET_INTERFACE 0x5818
+
+#define MBOX_BUSY_BIT 31
+#define MBOX_RETRY_COUNT 100
+
+#define MBOX_DATA_BIT_VALID 31
+#define MBOX_DATA_BIT_AC_DC 30
+
+static DEFINE_MUTEX(mbox_lock);
+
+static int send_mbox_cmd(struct pci_dev *pdev, u8 cmd_id, u32 cmd_data, u8 *cmd_resp)
+{
+ struct proc_thermal_device *proc_priv;
+ u32 retries, data;
+ int ret;
+
+ mutex_lock(&mbox_lock);
+ proc_priv = pci_get_drvdata(pdev);
+
+ /* Poll for rb bit == 0 */
+ retries = MBOX_RETRY_COUNT;
+ do {
+ data = readl((void __iomem *) (proc_priv->mmio_base + MBOX_OFFSET_INTERFACE));
+ if (data & BIT_ULL(MBOX_BUSY_BIT)) {
+ ret = -EBUSY;
+ continue;
+ }
+ ret = 0;
+ break;
+ } while (--retries);
+
+ if (ret)
+ goto unlock_mbox;
+
+ if (cmd_id == MBOX_CMD_WORKLOAD_TYPE_WRITE)
+ writel(cmd_data, (void __iomem *) ((proc_priv->mmio_base + MBOX_OFFSET_DATA)));
+
+ /* Write command register */
+ data = BIT_ULL(MBOX_BUSY_BIT) | cmd_id;
+ writel(data, (void __iomem *) ((proc_priv->mmio_base + MBOX_OFFSET_INTERFACE)));
+
+ /* Poll for rb bit == 0 */
+ retries = MBOX_RETRY_COUNT;
+ do {
+ data = readl((void __iomem *) (proc_priv->mmio_base + MBOX_OFFSET_INTERFACE));
+ if (data & BIT_ULL(MBOX_BUSY_BIT)) {
+ ret = -EBUSY;
+ continue;
+ }
+
+ if (data) {
+ ret = -ENXIO;
+ goto unlock_mbox;
+ }
+
+ if (cmd_id == MBOX_CMD_WORKLOAD_TYPE_READ) {
+ data = readl((void __iomem *) (proc_priv->mmio_base + MBOX_OFFSET_DATA));
+ *cmd_resp = data & 0xff;
+ }
+
+ ret = 0;
+ break;
+ } while (--retries);
+
+unlock_mbox:
+ mutex_unlock(&mbox_lock);
+ return ret;
+}
+
+/* List of workload types */
+static const char * const workload_types[] = {
+ "none",
+ "idle",
+ "semi_active",
+ "burusty",
+ "sustained",
+ "battery_life",
+ NULL
+};
+
+
+static ssize_t workload_available_types_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int i = 0;
+ int ret = 0;
+
+ while (workload_types[i] != NULL)
+ ret += sprintf(&buf[ret], "%s ", workload_types[i++]);
+
+ ret += sprintf(&buf[ret], "\n");
+
+ return ret;
+}
+
+static DEVICE_ATTR_RO(workload_available_types);
+
+static ssize_t workload_type_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ char str_preference[15];
+ u32 data = 0;
+ ssize_t ret;
+
+ ret = sscanf(buf, "%14s", str_preference);
+ if (ret != 1)
+ return -EINVAL;
+
+ ret = match_string(workload_types, -1, str_preference);
+ if (ret < 0)
+ return ret;
+
+ ret &= 0xff;
+
+ if (ret)
+ data = BIT(MBOX_DATA_BIT_VALID) | BIT(MBOX_DATA_BIT_AC_DC);
+
+ data |= ret;
+
+ ret = send_mbox_cmd(pdev, MBOX_CMD_WORKLOAD_TYPE_WRITE, data, NULL);
+ if (ret)
+ return false;
+
+ return count;
+}
+
+static ssize_t workload_type_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ u8 cmd_resp;
+ int ret;
+
+ ret = send_mbox_cmd(pdev, MBOX_CMD_WORKLOAD_TYPE_READ, 0, &cmd_resp);
+ if (ret)
+ return false;
+
+ cmd_resp &= 0xff;
+
+ if (cmd_resp > ARRAY_SIZE(workload_types) - 1)
+ return -EINVAL;
+
+ return sprintf(buf, "%s\n", workload_types[cmd_resp]);
+}
+
+static DEVICE_ATTR_RW(workload_type);
+
+static struct attribute *workload_req_attrs[] = {
+ &dev_attr_workload_available_types.attr,
+ &dev_attr_workload_type.attr,
+ NULL
+};
+
+static const struct attribute_group workload_req_attribute_group = {
+ .attrs = workload_req_attrs,
+ .name = "workload_request"
+};
+
+
+
+static bool workload_req_created;
+
+int proc_thermal_mbox_add(struct pci_dev *pdev, struct proc_thermal_device *proc_priv)
+{
+ u8 cmd_resp;
+ int ret;
+
+ /* Check if there is a mailbox support, if fails return success */
+ ret = send_mbox_cmd(pdev, MBOX_CMD_WORKLOAD_TYPE_READ, 0, &cmd_resp);
+ if (ret)
+ return 0;
+
+ ret = sysfs_create_group(&pdev->dev.kobj, &workload_req_attribute_group);
+ if (ret)
+ return ret;
+
+ workload_req_created = true;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(proc_thermal_mbox_add);
+
+void proc_thermal_mbox_remove(struct pci_dev *pdev)
+{
+ if (workload_req_created)
+ sysfs_remove_group(&pdev->dev.kobj, &workload_req_attribute_group);
+
+ workload_req_created = false;
+
+}
+EXPORT_SYMBOL_GPL(proc_thermal_mbox_remove);
+
+MODULE_LICENSE("GPL v2");
--
2.25.4