/* * Hisilicon thermal sensor driver * * Copyright (c) 2014-2015 Hisilicon Limited. * Copyright (c) 2014-2015 Linaro Limited. * * Xinwei Kong * Leo Yan * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed "as is" WITHOUT ANY WARRANTY of any * kind, whether express or implied; without even the implied warranty * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include #include #include #include #include #include #include "thermal_core.h" #define TEMP0_LAG (0x0) #define TEMP0_TH (0x4) #define TEMP0_RST_TH (0x8) #define TEMP0_CFG (0xC) #define TEMP0_CFG_SS_MSK (0xF000) #define TEMP0_CFG_HDAK_MSK (0x30) #define TEMP0_EN (0x10) #define TEMP0_INT_EN (0x14) #define TEMP0_INT_CLR (0x18) #define TEMP0_RST_MSK (0x1C) #define TEMP0_VALUE (0x28) #define HISI_TEMP_BASE (-60000) #define HISI_TEMP_RESET (100000) #define HISI_TEMP_STEP (785) #define HISI_TEMP_LAG (3500) #define HISI_MAX_SENSORS 4 #define HISI_DEFAULT_SENSOR 2 struct hisi_thermal_sensor { struct thermal_zone_device *tzd; uint32_t id; uint32_t thres_temp; }; struct hisi_thermal_data { struct platform_device *pdev; struct clk *clk; struct hisi_thermal_sensor sensor; void __iomem *regs; int irq; }; /* * The temperature computation on the tsensor is as follow: * Unit: millidegree Celsius * Step: 200/255 (0.7843) * Temperature base: -60°C * * The register is programmed in temperature steps, every step is 785 * millidegree and begins at -60 000 m°C * * The temperature from the steps: * * Temp = TempBase + (steps x 785) * * and the steps from the temperature: * * steps = (Temp - TempBase) / 785 * */ static inline int hisi_thermal_step_to_temp(int step) { return HISI_TEMP_BASE + (step * HISI_TEMP_STEP); } static inline int hisi_thermal_temp_to_step(int temp) { return DIV_ROUND_UP(temp - HISI_TEMP_BASE, HISI_TEMP_STEP); } /* * The lag register contains 5 bits encoding the temperature in steps. * * Each time the temperature crosses the threshold boundary, an * interrupt is raised. It could be when the temperature is going * above the threshold or below. However, if the temperature is * fluctuating around this value due to the load, we can receive * several interrupts which may not desired. * * We can setup a temperature representing the delta between the * threshold and the current temperature when the temperature is * decreasing. * * For instance: the lag register is 5°C, the threshold is 65°C, when * the temperature reaches 65°C an interrupt is raised and when the * temperature decrease to 65°C - 5°C another interrupt is raised. * * A very short lag can lead to an interrupt storm, a long lag * increase the latency to react to the temperature changes. In our * case, that is not really a problem as we are polling the * temperature. * * [0:4] : lag register * * The temperature is coded in steps, cf. HISI_TEMP_STEP. * * Min : 0x00 : 0.0 °C * Max : 0x1F : 24.3 °C * * The 'value' parameter is in milliCelsius. */ static inline void hisi_thermal_set_lag(void __iomem *addr, int value) { writel(DIV_ROUND_UP(value, HISI_TEMP_STEP) & 0x1F, addr + TEMP0_LAG); } static inline void hisi_thermal_alarm_clear(void __iomem *addr, int value) { writel(value, addr + TEMP0_INT_CLR); } static inline void hisi_thermal_alarm_enable(void __iomem *addr, int value) { writel(value, addr + TEMP0_INT_EN); } static inline void hisi_thermal_alarm_set(void __iomem *addr, int temp) { writel(hisi_thermal_temp_to_step(temp) | 0x0FFFFFF00, addr + TEMP0_TH); } static inline void hisi_thermal_reset_set(void __iomem *addr, int temp) { writel(hisi_thermal_temp_to_step(temp), addr + TEMP0_RST_TH); } static inline void hisi_thermal_reset_enable(void __iomem *addr, int value) { writel(value, addr + TEMP0_RST_MSK); } static inline void hisi_thermal_enable(void __iomem *addr, int value) { writel(value, addr + TEMP0_EN); } static inline int hisi_thermal_get_temperature(void __iomem *addr) { return hisi_thermal_step_to_temp(readl(addr + TEMP0_VALUE)); } /* * Temperature configuration register - Sensor selection * * Bits [19:12] * * 0x0: local sensor (default) * 0x1: remote sensor 1 (ACPU cluster 1) * 0x2: remote sensor 2 (ACPU cluster 0) * 0x3: remote sensor 3 (G3D) */ static inline void hisi_thermal_sensor_select(void __iomem *addr, int sensor) { writel((readl(addr + TEMP0_CFG) & ~TEMP0_CFG_SS_MSK) | (sensor << 12), addr + TEMP0_CFG); } /* * Temperature configuration register - Hdak conversion polling interval * * Bits [5:4] * * 0x0 : 0.768 ms * 0x1 : 6.144 ms * 0x2 : 49.152 ms * 0x3 : 393.216 ms */ static inline void hisi_thermal_hdak_set(void __iomem *addr, int value) { writel((readl(addr + TEMP0_CFG) & ~TEMP0_CFG_HDAK_MSK) | (value << 4), addr + TEMP0_CFG); } static void hisi_thermal_disable_sensor(struct hisi_thermal_data *data) { /* disable sensor module */ hisi_thermal_enable(data->regs, 0); hisi_thermal_alarm_enable(data->regs, 0); hisi_thermal_reset_enable(data->regs, 0); clk_disable_unprepare(data->clk); } static int hisi_thermal_get_temp(void *__data, int *temp) { struct hisi_thermal_data *data = __data; struct hisi_thermal_sensor *sensor = &data->sensor; *temp = hisi_thermal_get_temperature(data->regs); dev_dbg(&data->pdev->dev, "id=%d, temp=%d, thres=%d\n", sensor->id, *temp, sensor->thres_temp); return 0; } static const struct thermal_zone_of_device_ops hisi_of_thermal_ops = { .get_temp = hisi_thermal_get_temp, }; static irqreturn_t hisi_thermal_alarm_irq_thread(int irq, void *dev) { struct hisi_thermal_data *data = dev; struct hisi_thermal_sensor *sensor = &data->sensor; int temp; hisi_thermal_alarm_clear(data->regs, 1); temp = hisi_thermal_get_temperature(data->regs); if (temp >= sensor->thres_temp) { dev_crit(&data->pdev->dev, "THERMAL ALARM: %d > %d\n", temp, sensor->thres_temp); thermal_zone_device_update(data->sensor.tzd, THERMAL_EVENT_UNSPECIFIED); } else if (temp < sensor->thres_temp) { dev_crit(&data->pdev->dev, "THERMAL ALARM stopped: %d < %d\n", temp, sensor->thres_temp); } return IRQ_HANDLED; } static int hisi_thermal_register_sensor(struct platform_device *pdev, struct hisi_thermal_data *data, struct hisi_thermal_sensor *sensor, int index) { int ret, i; const struct thermal_trip *trip; sensor->id = index; sensor->tzd = devm_thermal_zone_of_sensor_register(&pdev->dev, sensor->id, data, &hisi_of_thermal_ops); if (IS_ERR(sensor->tzd)) { ret = PTR_ERR(sensor->tzd); sensor->tzd = NULL; dev_err(&pdev->dev, "failed to register sensor id %d: %d\n", sensor->id, ret); return ret; } trip = of_thermal_get_trip_points(sensor->tzd); for (i = 0; i < of_thermal_get_ntrips(sensor->tzd); i++) { if (trip[i].type == THERMAL_TRIP_PASSIVE) { sensor->thres_temp = trip[i].temperature; break; } } return 0; } static const struct of_device_id of_hisi_thermal_match[] = { { .compatible = "hisilicon,tsensor" }, { /* end */ } }; MODULE_DEVICE_TABLE(of, of_hisi_thermal_match); static void hisi_thermal_toggle_sensor(struct hisi_thermal_sensor *sensor, bool on) { struct thermal_zone_device *tzd = sensor->tzd; tzd->ops->set_mode(tzd, on ? THERMAL_DEVICE_ENABLED : THERMAL_DEVICE_DISABLED); } static int hisi_thermal_setup(struct hisi_thermal_data *data) { struct hisi_thermal_sensor *sensor = &data->sensor; int ret; /* enable clock for tsensor */ ret = clk_prepare_enable(data->clk); if (ret) return ret; /* disable module firstly */ hisi_thermal_reset_enable(data->regs, 0); hisi_thermal_enable(data->regs, 0); /* select sensor id */ hisi_thermal_sensor_select(data->regs, sensor->id); /* setting the hdak time */ hisi_thermal_hdak_set(data->regs, 0); /* setting lag value between current temp and the threshold */ hisi_thermal_set_lag(data->regs, HISI_TEMP_LAG); /* enable for interrupt */ hisi_thermal_alarm_set(data->regs, sensor->thres_temp); hisi_thermal_reset_set(data->regs, HISI_TEMP_RESET); /* enable module */ hisi_thermal_reset_enable(data->regs, 1); hisi_thermal_enable(data->regs, 1); hisi_thermal_alarm_clear(data->regs, 0); hisi_thermal_alarm_enable(data->regs, 1); return 0; } static int hisi_thermal_probe(struct platform_device *pdev) { struct hisi_thermal_data *data; struct resource *res; int ret; data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); if (!data) return -ENOMEM; data->pdev = pdev; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); data->regs = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(data->regs)) { dev_err(&pdev->dev, "failed to get io address\n"); return PTR_ERR(data->regs); } data->irq = platform_get_irq(pdev, 0); if (data->irq < 0) return data->irq; platform_set_drvdata(pdev, data); data->clk = devm_clk_get(&pdev->dev, "thermal_clk"); if (IS_ERR(data->clk)) { ret = PTR_ERR(data->clk); if (ret != -EPROBE_DEFER) dev_err(&pdev->dev, "failed to get thermal clk: %d\n", ret); return ret; } ret = hisi_thermal_register_sensor(pdev, data, &data->sensor, HISI_DEFAULT_SENSOR); if (ret) { dev_err(&pdev->dev, "failed to register thermal sensor: %d\n", ret); return ret; } ret = hisi_thermal_setup(data); if (ret) { dev_err(&pdev->dev, "Failed to setup the sensor: %d\n", ret); return ret; } ret = devm_request_threaded_irq(&pdev->dev, data->irq, NULL, hisi_thermal_alarm_irq_thread, IRQF_ONESHOT, "hisi_thermal", data); if (ret < 0) { dev_err(&pdev->dev, "failed to request alarm irq: %d\n", ret); return ret; } hisi_thermal_toggle_sensor(&data->sensor, true); return 0; } static int hisi_thermal_remove(struct platform_device *pdev) { struct hisi_thermal_data *data = platform_get_drvdata(pdev); struct hisi_thermal_sensor *sensor = &data->sensor; hisi_thermal_toggle_sensor(sensor, false); hisi_thermal_disable_sensor(data); return 0; } #ifdef CONFIG_PM_SLEEP static int hisi_thermal_suspend(struct device *dev) { struct hisi_thermal_data *data = dev_get_drvdata(dev); hisi_thermal_disable_sensor(data); return 0; } static int hisi_thermal_resume(struct device *dev) { struct hisi_thermal_data *data = dev_get_drvdata(dev); return hisi_thermal_setup(data); } #endif static SIMPLE_DEV_PM_OPS(hisi_thermal_pm_ops, hisi_thermal_suspend, hisi_thermal_resume); static struct platform_driver hisi_thermal_driver = { .driver = { .name = "hisi_thermal", .pm = &hisi_thermal_pm_ops, .of_match_table = of_hisi_thermal_match, }, .probe = hisi_thermal_probe, .remove = hisi_thermal_remove, }; module_platform_driver(hisi_thermal_driver); MODULE_AUTHOR("Xinwei Kong "); MODULE_AUTHOR("Leo Yan "); MODULE_DESCRIPTION("Hisilicon thermal driver"); MODULE_LICENSE("GPL v2");