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-rw-r--r--drivers/thermal/rcar_gen3_thermal.c525
1 files changed, 525 insertions, 0 deletions
diff --git a/drivers/thermal/rcar_gen3_thermal.c b/drivers/thermal/rcar_gen3_thermal.c
new file mode 100644
index 000000000..c4f28752d
--- /dev/null
+++ b/drivers/thermal/rcar_gen3_thermal.c
@@ -0,0 +1,525 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * R-Car Gen3 THS thermal sensor driver
+ * Based on rcar_thermal.c and work from Hien Dang and Khiem Nguyen.
+ *
+ * Copyright (C) 2016 Renesas Electronics Corporation.
+ * Copyright (C) 2016 Sang Engineering
+ */
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/sys_soc.h>
+#include <linux/thermal.h>
+
+#include "thermal_core.h"
+#include "thermal_hwmon.h"
+
+/* Register offsets */
+#define REG_GEN3_IRQSTR 0x04
+#define REG_GEN3_IRQMSK 0x08
+#define REG_GEN3_IRQCTL 0x0C
+#define REG_GEN3_IRQEN 0x10
+#define REG_GEN3_IRQTEMP1 0x14
+#define REG_GEN3_IRQTEMP2 0x18
+#define REG_GEN3_IRQTEMP3 0x1C
+#define REG_GEN3_CTSR 0x20
+#define REG_GEN3_THCTR 0x20
+#define REG_GEN3_TEMP 0x28
+#define REG_GEN3_THCODE1 0x50
+#define REG_GEN3_THCODE2 0x54
+#define REG_GEN3_THCODE3 0x58
+
+/* IRQ{STR,MSK,EN} bits */
+#define IRQ_TEMP1 BIT(0)
+#define IRQ_TEMP2 BIT(1)
+#define IRQ_TEMP3 BIT(2)
+#define IRQ_TEMPD1 BIT(3)
+#define IRQ_TEMPD2 BIT(4)
+#define IRQ_TEMPD3 BIT(5)
+
+/* CTSR bits */
+#define CTSR_PONM BIT(8)
+#define CTSR_AOUT BIT(7)
+#define CTSR_THBGR BIT(5)
+#define CTSR_VMEN BIT(4)
+#define CTSR_VMST BIT(1)
+#define CTSR_THSST BIT(0)
+
+/* THCTR bits */
+#define THCTR_PONM BIT(6)
+#define THCTR_THSST BIT(0)
+
+#define CTEMP_MASK 0xFFF
+
+#define MCELSIUS(temp) ((temp) * 1000)
+#define GEN3_FUSE_MASK 0xFFF
+
+#define TSC_MAX_NUM 3
+
+/* default THCODE values if FUSEs are missing */
+static const int thcodes[TSC_MAX_NUM][3] = {
+ { 3397, 2800, 2221 },
+ { 3393, 2795, 2216 },
+ { 3389, 2805, 2237 },
+};
+
+/* Structure for thermal temperature calculation */
+struct equation_coefs {
+ int a1;
+ int b1;
+ int a2;
+ int b2;
+};
+
+struct rcar_gen3_thermal_tsc {
+ void __iomem *base;
+ struct thermal_zone_device *zone;
+ struct equation_coefs coef;
+ int tj_t;
+ int id; /* thermal channel id */
+};
+
+struct rcar_gen3_thermal_priv {
+ struct rcar_gen3_thermal_tsc *tscs[TSC_MAX_NUM];
+ unsigned int num_tscs;
+ void (*thermal_init)(struct rcar_gen3_thermal_tsc *tsc);
+};
+
+static inline u32 rcar_gen3_thermal_read(struct rcar_gen3_thermal_tsc *tsc,
+ u32 reg)
+{
+ return ioread32(tsc->base + reg);
+}
+
+static inline void rcar_gen3_thermal_write(struct rcar_gen3_thermal_tsc *tsc,
+ u32 reg, u32 data)
+{
+ iowrite32(data, tsc->base + reg);
+}
+
+/*
+ * Linear approximation for temperature
+ *
+ * [reg] = [temp] * a + b => [temp] = ([reg] - b) / a
+ *
+ * The constants a and b are calculated using two triplets of int values PTAT
+ * and THCODE. PTAT and THCODE can either be read from hardware or use hard
+ * coded values from driver. The formula to calculate a and b are taken from
+ * BSP and sparsely documented and understood.
+ *
+ * Examining the linear formula and the formula used to calculate constants a
+ * and b while knowing that the span for PTAT and THCODE values are between
+ * 0x000 and 0xfff the largest integer possible is 0xfff * 0xfff == 0xffe001.
+ * Integer also needs to be signed so that leaves 7 bits for binary
+ * fixed point scaling.
+ */
+
+#define FIXPT_SHIFT 7
+#define FIXPT_INT(_x) ((_x) << FIXPT_SHIFT)
+#define INT_FIXPT(_x) ((_x) >> FIXPT_SHIFT)
+#define FIXPT_DIV(_a, _b) DIV_ROUND_CLOSEST(((_a) << FIXPT_SHIFT), (_b))
+#define FIXPT_TO_MCELSIUS(_x) ((_x) * 1000 >> FIXPT_SHIFT)
+
+#define RCAR3_THERMAL_GRAN 500 /* mili Celsius */
+
+/* no idea where these constants come from */
+#define TJ_3 -41
+
+static void rcar_gen3_thermal_calc_coefs(struct rcar_gen3_thermal_tsc *tsc,
+ int *ptat, const int *thcode,
+ int ths_tj_1)
+{
+ /* TODO: Find documentation and document constant calculation formula */
+
+ /*
+ * Division is not scaled in BSP and if scaled it might overflow
+ * the dividend (4095 * 4095 << 14 > INT_MAX) so keep it unscaled
+ */
+ tsc->tj_t = (FIXPT_INT((ptat[1] - ptat[2]) * (ths_tj_1 - TJ_3))
+ / (ptat[0] - ptat[2])) + FIXPT_INT(TJ_3);
+
+ tsc->coef.a1 = FIXPT_DIV(FIXPT_INT(thcode[1] - thcode[2]),
+ tsc->tj_t - FIXPT_INT(TJ_3));
+ tsc->coef.b1 = FIXPT_INT(thcode[2]) - tsc->coef.a1 * TJ_3;
+
+ tsc->coef.a2 = FIXPT_DIV(FIXPT_INT(thcode[1] - thcode[0]),
+ tsc->tj_t - FIXPT_INT(ths_tj_1));
+ tsc->coef.b2 = FIXPT_INT(thcode[0]) - tsc->coef.a2 * ths_tj_1;
+}
+
+static int rcar_gen3_thermal_round(int temp)
+{
+ int result, round_offs;
+
+ round_offs = temp >= 0 ? RCAR3_THERMAL_GRAN / 2 :
+ -RCAR3_THERMAL_GRAN / 2;
+ result = (temp + round_offs) / RCAR3_THERMAL_GRAN;
+ return result * RCAR3_THERMAL_GRAN;
+}
+
+static int rcar_gen3_thermal_get_temp(void *devdata, int *temp)
+{
+ struct rcar_gen3_thermal_tsc *tsc = devdata;
+ int mcelsius, val;
+ int reg;
+
+ /* Read register and convert to mili Celsius */
+ reg = rcar_gen3_thermal_read(tsc, REG_GEN3_TEMP) & CTEMP_MASK;
+
+ if (reg <= thcodes[tsc->id][1])
+ val = FIXPT_DIV(FIXPT_INT(reg) - tsc->coef.b1,
+ tsc->coef.a1);
+ else
+ val = FIXPT_DIV(FIXPT_INT(reg) - tsc->coef.b2,
+ tsc->coef.a2);
+ mcelsius = FIXPT_TO_MCELSIUS(val);
+
+ /* Guaranteed operating range is -40C to 125C. */
+
+ /* Round value to device granularity setting */
+ *temp = rcar_gen3_thermal_round(mcelsius);
+
+ return 0;
+}
+
+static int rcar_gen3_thermal_mcelsius_to_temp(struct rcar_gen3_thermal_tsc *tsc,
+ int mcelsius)
+{
+ int celsius, val;
+
+ celsius = DIV_ROUND_CLOSEST(mcelsius, 1000);
+ if (celsius <= INT_FIXPT(tsc->tj_t))
+ val = celsius * tsc->coef.a1 + tsc->coef.b1;
+ else
+ val = celsius * tsc->coef.a2 + tsc->coef.b2;
+
+ return INT_FIXPT(val);
+}
+
+static int rcar_gen3_thermal_update_range(struct rcar_gen3_thermal_tsc *tsc)
+{
+ int temperature, low, high;
+
+ rcar_gen3_thermal_get_temp(tsc, &temperature);
+
+ low = temperature - MCELSIUS(1);
+ high = temperature + MCELSIUS(1);
+
+ rcar_gen3_thermal_write(tsc, REG_GEN3_IRQTEMP1,
+ rcar_gen3_thermal_mcelsius_to_temp(tsc, low));
+
+ rcar_gen3_thermal_write(tsc, REG_GEN3_IRQTEMP2,
+ rcar_gen3_thermal_mcelsius_to_temp(tsc, high));
+
+ return 0;
+}
+
+static const struct thermal_zone_of_device_ops rcar_gen3_tz_of_ops = {
+ .get_temp = rcar_gen3_thermal_get_temp,
+};
+
+static void rcar_thermal_irq_set(struct rcar_gen3_thermal_priv *priv, bool on)
+{
+ unsigned int i;
+ u32 val = on ? IRQ_TEMPD1 | IRQ_TEMP2 : 0;
+
+ for (i = 0; i < priv->num_tscs; i++)
+ rcar_gen3_thermal_write(priv->tscs[i], REG_GEN3_IRQMSK, val);
+}
+
+static irqreturn_t rcar_gen3_thermal_irq(int irq, void *data)
+{
+ struct rcar_gen3_thermal_priv *priv = data;
+ u32 status;
+ int i;
+
+ for (i = 0; i < priv->num_tscs; i++) {
+ status = rcar_gen3_thermal_read(priv->tscs[i], REG_GEN3_IRQSTR);
+ rcar_gen3_thermal_write(priv->tscs[i], REG_GEN3_IRQSTR, 0);
+ if (status) {
+ rcar_gen3_thermal_update_range(priv->tscs[i]);
+ thermal_zone_device_update(priv->tscs[i]->zone,
+ THERMAL_EVENT_UNSPECIFIED);
+ }
+ }
+
+ return IRQ_HANDLED;
+}
+
+static const struct soc_device_attribute r8a7795es1[] = {
+ { .soc_id = "r8a7795", .revision = "ES1.*" },
+ { /* sentinel */ }
+};
+
+static void rcar_gen3_thermal_init_r8a7795es1(struct rcar_gen3_thermal_tsc *tsc)
+{
+ rcar_gen3_thermal_write(tsc, REG_GEN3_CTSR, CTSR_THBGR);
+ rcar_gen3_thermal_write(tsc, REG_GEN3_CTSR, 0x0);
+
+ usleep_range(1000, 2000);
+
+ rcar_gen3_thermal_write(tsc, REG_GEN3_CTSR, CTSR_PONM);
+
+ rcar_gen3_thermal_write(tsc, REG_GEN3_IRQCTL, 0x3F);
+ rcar_gen3_thermal_write(tsc, REG_GEN3_IRQMSK, 0);
+ rcar_gen3_thermal_write(tsc, REG_GEN3_IRQEN, IRQ_TEMPD1 | IRQ_TEMP2);
+
+ rcar_gen3_thermal_write(tsc, REG_GEN3_CTSR,
+ CTSR_PONM | CTSR_AOUT | CTSR_THBGR | CTSR_VMEN);
+
+ usleep_range(100, 200);
+
+ rcar_gen3_thermal_write(tsc, REG_GEN3_CTSR,
+ CTSR_PONM | CTSR_AOUT | CTSR_THBGR | CTSR_VMEN |
+ CTSR_VMST | CTSR_THSST);
+
+ usleep_range(1000, 2000);
+}
+
+static void rcar_gen3_thermal_init(struct rcar_gen3_thermal_tsc *tsc)
+{
+ u32 reg_val;
+
+ reg_val = rcar_gen3_thermal_read(tsc, REG_GEN3_THCTR);
+ reg_val &= ~THCTR_PONM;
+ rcar_gen3_thermal_write(tsc, REG_GEN3_THCTR, reg_val);
+
+ usleep_range(1000, 2000);
+
+ rcar_gen3_thermal_write(tsc, REG_GEN3_IRQCTL, 0);
+ rcar_gen3_thermal_write(tsc, REG_GEN3_IRQMSK, 0);
+ rcar_gen3_thermal_write(tsc, REG_GEN3_IRQEN, IRQ_TEMPD1 | IRQ_TEMP2);
+
+ reg_val = rcar_gen3_thermal_read(tsc, REG_GEN3_THCTR);
+ reg_val |= THCTR_THSST;
+ rcar_gen3_thermal_write(tsc, REG_GEN3_THCTR, reg_val);
+
+ usleep_range(1000, 2000);
+}
+
+static const int rcar_gen3_ths_tj_1 = 126;
+static const int rcar_gen3_ths_tj_1_m3_w = 116;
+static const struct of_device_id rcar_gen3_thermal_dt_ids[] = {
+ {
+ .compatible = "renesas,r8a774a1-thermal",
+ .data = &rcar_gen3_ths_tj_1_m3_w,
+ },
+ {
+ .compatible = "renesas,r8a774b1-thermal",
+ .data = &rcar_gen3_ths_tj_1,
+ },
+ {
+ .compatible = "renesas,r8a774e1-thermal",
+ .data = &rcar_gen3_ths_tj_1,
+ },
+ {
+ .compatible = "renesas,r8a7795-thermal",
+ .data = &rcar_gen3_ths_tj_1,
+ },
+ {
+ .compatible = "renesas,r8a7796-thermal",
+ .data = &rcar_gen3_ths_tj_1_m3_w,
+ },
+ {
+ .compatible = "renesas,r8a77961-thermal",
+ .data = &rcar_gen3_ths_tj_1_m3_w,
+ },
+ {
+ .compatible = "renesas,r8a77965-thermal",
+ .data = &rcar_gen3_ths_tj_1,
+ },
+ {
+ .compatible = "renesas,r8a77980-thermal",
+ .data = &rcar_gen3_ths_tj_1,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, rcar_gen3_thermal_dt_ids);
+
+static int rcar_gen3_thermal_remove(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct rcar_gen3_thermal_priv *priv = dev_get_drvdata(dev);
+
+ rcar_thermal_irq_set(priv, false);
+
+ pm_runtime_put(dev);
+ pm_runtime_disable(dev);
+
+ return 0;
+}
+
+static void rcar_gen3_hwmon_action(void *data)
+{
+ struct thermal_zone_device *zone = data;
+
+ thermal_remove_hwmon_sysfs(zone);
+}
+
+static int rcar_gen3_thermal_probe(struct platform_device *pdev)
+{
+ struct rcar_gen3_thermal_priv *priv;
+ struct device *dev = &pdev->dev;
+ const int *ths_tj_1 = of_device_get_match_data(dev);
+ struct resource *res;
+ struct thermal_zone_device *zone;
+ int ret, irq, i;
+ char *irqname;
+
+ /* default values if FUSEs are missing */
+ /* TODO: Read values from hardware on supported platforms */
+ int ptat[3] = { 2631, 1509, 435 };
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->thermal_init = rcar_gen3_thermal_init;
+ if (soc_device_match(r8a7795es1))
+ priv->thermal_init = rcar_gen3_thermal_init_r8a7795es1;
+
+ platform_set_drvdata(pdev, priv);
+
+ /*
+ * Request 2 (of the 3 possible) IRQs, the driver only needs to
+ * to trigger on the low and high trip points of the current
+ * temp window at this point.
+ */
+ for (i = 0; i < 2; i++) {
+ irq = platform_get_irq(pdev, i);
+ if (irq < 0)
+ return irq;
+
+ irqname = devm_kasprintf(dev, GFP_KERNEL, "%s:ch%d",
+ dev_name(dev), i);
+ if (!irqname)
+ return -ENOMEM;
+
+ ret = devm_request_threaded_irq(dev, irq, NULL,
+ rcar_gen3_thermal_irq,
+ IRQF_ONESHOT, irqname, priv);
+ if (ret)
+ return ret;
+ }
+
+ pm_runtime_enable(dev);
+ pm_runtime_get_sync(dev);
+
+ for (i = 0; i < TSC_MAX_NUM; i++) {
+ struct rcar_gen3_thermal_tsc *tsc;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, i);
+ if (!res)
+ break;
+
+ tsc = devm_kzalloc(dev, sizeof(*tsc), GFP_KERNEL);
+ if (!tsc) {
+ ret = -ENOMEM;
+ goto error_unregister;
+ }
+
+ tsc->base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(tsc->base)) {
+ ret = PTR_ERR(tsc->base);
+ goto error_unregister;
+ }
+ tsc->id = i;
+
+ priv->tscs[i] = tsc;
+
+ priv->thermal_init(tsc);
+ rcar_gen3_thermal_calc_coefs(tsc, ptat, thcodes[i], *ths_tj_1);
+
+ zone = devm_thermal_zone_of_sensor_register(dev, i, tsc,
+ &rcar_gen3_tz_of_ops);
+ if (IS_ERR(zone)) {
+ dev_err(dev, "Can't register thermal zone\n");
+ ret = PTR_ERR(zone);
+ goto error_unregister;
+ }
+ tsc->zone = zone;
+
+ tsc->zone->tzp->no_hwmon = false;
+ ret = thermal_add_hwmon_sysfs(tsc->zone);
+ if (ret)
+ goto error_unregister;
+
+ ret = devm_add_action_or_reset(dev, rcar_gen3_hwmon_action, zone);
+ if (ret)
+ goto error_unregister;
+
+ ret = of_thermal_get_ntrips(tsc->zone);
+ if (ret < 0)
+ goto error_unregister;
+
+ rcar_gen3_thermal_update_range(tsc);
+
+ dev_info(dev, "TSC%d: Loaded %d trip points\n", i, ret);
+ }
+
+ priv->num_tscs = i;
+
+ if (!priv->num_tscs) {
+ ret = -ENODEV;
+ goto error_unregister;
+ }
+
+ rcar_thermal_irq_set(priv, true);
+
+ return 0;
+
+error_unregister:
+ rcar_gen3_thermal_remove(pdev);
+
+ return ret;
+}
+
+static int __maybe_unused rcar_gen3_thermal_suspend(struct device *dev)
+{
+ struct rcar_gen3_thermal_priv *priv = dev_get_drvdata(dev);
+
+ rcar_thermal_irq_set(priv, false);
+
+ return 0;
+}
+
+static int __maybe_unused rcar_gen3_thermal_resume(struct device *dev)
+{
+ struct rcar_gen3_thermal_priv *priv = dev_get_drvdata(dev);
+ unsigned int i;
+
+ for (i = 0; i < priv->num_tscs; i++) {
+ struct rcar_gen3_thermal_tsc *tsc = priv->tscs[i];
+
+ priv->thermal_init(tsc);
+ rcar_gen3_thermal_update_range(tsc);
+ }
+
+ rcar_thermal_irq_set(priv, true);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(rcar_gen3_thermal_pm_ops, rcar_gen3_thermal_suspend,
+ rcar_gen3_thermal_resume);
+
+static struct platform_driver rcar_gen3_thermal_driver = {
+ .driver = {
+ .name = "rcar_gen3_thermal",
+ .pm = &rcar_gen3_thermal_pm_ops,
+ .of_match_table = rcar_gen3_thermal_dt_ids,
+ },
+ .probe = rcar_gen3_thermal_probe,
+ .remove = rcar_gen3_thermal_remove,
+};
+module_platform_driver(rcar_gen3_thermal_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("R-Car Gen3 THS thermal sensor driver");
+MODULE_AUTHOR("Wolfram Sang <wsa+renesas@sang-engineering.com>");