diff options
Diffstat (limited to 'drivers/thermal/intel/int340x_thermal/processor_thermal_mbox.c')
| -rw-r--r-- | drivers/thermal/intel/int340x_thermal/processor_thermal_mbox.c | 212 |
1 files changed, 212 insertions, 0 deletions
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"); |