Add support for Airoha EN7581 thermal sensor. This provide support for
reading the CPU or SoC Package sensor and to setup trip points for hot
and critical condition. An interrupt is fired to react on this and
doesn't require passive poll to read the temperature.
The thermal regs provide a way to read the ADC value from an external
register placed in the Chip SCU regs. Monitor will read this value and
fire an interrupt if the trip condition configured is reached.
Signed-off-by: Christian Marangi <ansuelsmth@xxxxxxxxx>
---
drivers/thermal/airoha_thermal.c | 492 +++++++++++++++++++++++++++++++
1 file changed, 492 insertions(+)
create mode 100644 drivers/thermal/airoha_thermal.c
diff --git a/drivers/thermal/airoha_thermal.c b/drivers/thermal/airoha_thermal.c
new file mode 100644
index 000000000000..7fe2982c6a3b
--- /dev/null
+++ b/drivers/thermal/airoha_thermal.c
@@ -0,0 +1,492 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/delay.h>
+#include <linux/mfd/syscon.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/thermal.h>
+
+/* SCU regs */
+#define EN7581_PLLRG_PROTECT 0x268
+#define EN7581_PWD_TADC 0x2ec
+#define EN7581_MUX_TADC GENMASK(3, 1)
+#define EN7581_DOUT_TADC 0x2f8
+#define EN7581_DOUT_TADC_MASK GENMASK(15, 0)
+
+/* PTP_THERMAL regs */
+#define EN7581_TEMPMONCTL0 0x800
+#define EN7581_SENSE3_EN BIT(3)
+#define EN7581_SENSE2_EN BIT(2)
+#define EN7581_SENSE1_EN BIT(1)
+#define EN7581_SENSE0_EN BIT(0)
+#define EN7581_TEMPMONCTL1 0x804
+/* period unit calculated in BUS clock * 256 scaling-up */
+#define EN7581_PERIOD_UNIT GENMASK(9, 0)
+#define EN7581_TEMPMONCTL2 0x808
+#define EN7581_FILT_INTERVAL GENMASK(25, 16)
+#define EN7581_SEN_INTERVAL GENMASK(9, 0)
+#define EN7581_TEMPMONINT 0x80C
+#define EN7581_STAGE3_INT_EN BIT(31)
+#define EN7581_STAGE2_INT_EN BIT(30)
+#define EN7581_STAGE1_INT_EN BIT(29)
+#define EN7581_FILTER_INT_EN_3 BIT(28)
+#define EN7581_IMMD_INT_EN3 BIT(27)
+#define EN7581_NOHOTINTEN3 BIT(26)
+#define EN7581_HOFSINTEN3 BIT(25)
+#define EN7581_LOFSINTEN3 BIT(24)
+#define EN7581_HINTEN3 BIT(23)
+#define EN7581_CINTEN3 BIT(22)
+#define EN7581_FILTER_INT_EN_2 BIT(21)
+#define EN7581_FILTER_INT_EN_1 BIT(20)
+#define EN7581_FILTER_INT_EN_0 BIT(19)
+#define EN7581_IMMD_INT_EN2 BIT(18)
+#define EN7581_IMMD_INT_EN1 BIT(17)
+#define EN7581_IMMD_INT_EN0 BIT(16)
+#define EN7581_TIME_OUT_INT_EN BIT(15)
+#define EN7581_NOHOTINTEN2 BIT(14)
+#define EN7581_HOFSINTEN2 BIT(13)
+#define EN7581_LOFSINTEN2 BIT(12)
+#define EN7581_HINTEN2 BIT(11)
+#define EN7581_CINTEN2 BIT(10)
+#define EN7581_NOHOTINTEN1 BIT(9)
+#define EN7581_HOFSINTEN1 BIT(8)
+#define EN7581_LOFSINTEN1 BIT(7)
+#define EN7581_HINTEN1 BIT(6)
+#define EN7581_CINTEN1 BIT(5)
+#define EN7581_NOHOTINTEN0 BIT(4)
+/* Similar to COLD and HOT also these seems to be swapped in documentation */
+#define EN7581_LOFSINTEN0 BIT(3) /* In documentation: BIT(2) */
+#define EN7581_HOFSINTEN0 BIT(2) /* In documentation: BIT(3) */
+/* It seems documentation have these swapped as the HW
+ * - Fire BIT(1) when lower than EN7581_COLD_THRE
+ * - Fire BIT(0) and BIT(5) when higher than EN7581_HOT2NORMAL_THRE or
+ * EN7581_HOT_THRE
+ */
+#define EN7581_CINTEN0 BIT(1) /* In documentation: BIT(0) */
+#define EN7581_HINTEN0 BIT(0) /* In documentation: BIT(1) */
+#define EN7581_TEMPMONINTSTS 0x810
+#define EN7581_STAGE3_INT_STAT BIT(31)
+#define EN7581_STAGE2_INT_STAT BIT(30)
+#define EN7581_STAGE1_INT_STAT BIT(29)
+#define EN7581_FILTER_INT_STAT_3 BIT(28)
+#define EN7581_IMMD_INT_STS3 BIT(27)
+#define EN7581_NOHOTINTSTS3 BIT(26)
+#define EN7581_HOFSINTSTS3 BIT(25)
+#define EN7581_LOFSINTSTS3 BIT(24)
+#define EN7581_HINTSTS3 BIT(23)
+#define EN7581_CINTSTS3 BIT(22)
+#define EN7581_FILTER_INT_STAT_2 BIT(21)
+#define EN7581_FILTER_INT_STAT_1 BIT(20)
+#define EN7581_FILTER_INT_STAT_0 BIT(19)
+#define EN7581_IMMD_INT_STS2 BIT(18)
+#define EN7581_IMMD_INT_STS1 BIT(17)
+#define EN7581_IMMD_INT_STS0 BIT(16)
+#define EN7581_TIME_OUT_INT_STAT BIT(15)
+#define EN7581_NOHOTINTSTS2 BIT(14)
+#define EN7581_HOFSINTSTS2 BIT(13)
+#define EN7581_LOFSINTSTS2 BIT(12)
+#define EN7581_HINTSTS2 BIT(11)
+#define EN7581_CINTSTS2 BIT(10)
+#define EN7581_NOHOTINTSTS1 BIT(9)
+#define EN7581_HOFSINTSTS1 BIT(8)
+#define EN7581_LOFSINTSTS1 BIT(7)
+#define EN7581_HINTSTS1 BIT(6)
+#define EN7581_CINTSTS1 BIT(5)
+#define EN7581_NOHOTINTSTS0 BIT(4)
+/* Similar to COLD and HOT also these seems to be swapped in documentation */
+#define EN7581_LOFSINTSTS0 BIT(3) /* In documentation: BIT(2) */
+#define EN7581_HOFSINTSTS0 BIT(2) /* In documentation: BIT(3) */
+/* It seems documentation have these swapped as the HW
+ * - Fire BIT(1) when lower than EN7581_COLD_THRE
+ * - Fire BIT(0) and BIT(5) when higher than EN7581_HOT2NORMAL_THRE or
+ * EN7581_HOT_THRE
+ *
+ * To clear things, we swap the define but we keep them documented here.
+ */
+#define EN7581_CINTSTS0 BIT(1) /* In documentation: BIT(0) */
+#define EN7581_HINTSTS0 BIT(0) /* In documentation: BIT(1)*/
+/* Monitor will take the bigger threshold between HOT2NORMAL and HOT
+ * and will fire both HOT2NORMAL and HOT interrupt when higher than the 2
+ *
+ * It has also been observed that not setting HOT2NORMAL makes the monitor
+ * treat COLD threshold as HOT2NORMAL.
+ */
+#define EN7581_TEMPH2NTHRE 0x824
+/* It seems HOT2NORMAL is actually NORMAL2HOT */
+#define EN7581_HOT2NORMAL_THRE GENMASK(11, 0)
+#define EN7581_TEMPHTHRE 0x828
+#define EN7581_HOT_THRE GENMASK(11, 0)
+/* Monitor will use this as HOT2NORMAL (fire interrupt when lower than...)*/
+#define EN7581_TEMPCTHRE 0x82c
+#define EN7581_COLD_THRE GENMASK(11, 0)
+/* Also LOW and HIGH offset register are swapped */
+#define EN7581_TEMPOFFSETL 0x830 /* In documentation: 0x834 */
+#define EN7581_LOW_OFFSET GENMASK(11, 0)
+#define EN7581_TEMPOFFSETH 0x834 /* In documentation: 0x830 */
+#define EN7581_HIGH_OFFSET GENMASK(11, 0)
+#define EN7581_TEMPMSRCTL0 0x838
+#define EN7581_MSRCTL3 GENMASK(11, 9)
+#define EN7581_MSRCTL2 GENMASK(8, 6)
+#define EN7581_MSRCTL1 GENMASK(5, 3)
+#define EN7581_MSRCTL0 GENMASK(2, 0)
+#define EN7581_TEMPADCVALIDADDR 0x878
+#define EN7581_ADC_VALID_ADDR GENMASK(31, 0)
+#define EN7581_TEMPADCVOLTADDR 0x87c
+#define EN7581_ADC_VOLT_ADDR GENMASK(31, 0)
+#define EN7581_TEMPRDCTRL 0x880
+/*
+ * NOTICE: AHB have this set to 0 by default. Means that
+ * the same addr is used for ADC volt and valid reading.
+ * In such case, VALID ADDR is used and volt addr is ignored.
+ */
+#define EN7581_RD_CTRL_DIFF BIT(0)
+#define EN7581_TEMPADCVALIDMASK 0x884
+#define EN7581_ADV_RD_VALID_POLARITY BIT(5)
+#define EN7581_ADV_RD_VALID_POS GENMASK(4, 0)
+#define EN7581_TEMPADCVOLTAGESHIFT 0x888
+#define EN7581_ADC_VOLTAGE_SHIFT GENMASK(4, 0)
+/*
+ * Same values for each CTL.
+ * Can operate in:
+ * - 1 sample
+ * - 2 sample and make average of them
+ * - 4,6,10,16 sample, drop max and min and make avgerage of them
+ */
+#define EN7581_MSRCTL_1SAMPLE 0x0
+#define EN7581_MSRCTL_AVG2SAMPLE 0x1
+#define EN7581_MSRCTL_4SAMPLE_MAX_MIX_AVG2 0x2
+#define EN7581_MSRCTL_6SAMPLE_MAX_MIX_AVG4 0x3
+#define EN7581_MSRCTL_10SAMPLE_MAX_MIX_AVG8 0x4
+#define EN7581_MSRCTL_18SAMPLE_MAX_MIX_AVG16 0x5
+#define EN7581_TEMPAHBPOLL 0x840
+#define EN7581_ADC_POLL_INTVL GENMASK(31, 0)
+/* PTPSPARE0,2 reg are used to store efuse info for calibrated temp offset */
+#define EN7581_EFUSE_TEMP_OFFSET_REG 0xf20 /* PTPSPARE0 */
+#define EN7581_EFUSE_TEMP_OFFSET GENMASK(31, 16)
+#define EN7581_PTPSPARE1 0xf24 /* PTPSPARE1 */
+#define EN7581_EFUSE_TEMP_CPU_SENSOR_REG 0xf28 /* PTPSPARE2 */
+
+#define EN7581_SLOPE_X100_DIO_DEFAULT 5645
+#define EN7581_SLOPE_X100_DIO_AVS 5645
+
+#define EN7581_INIT_TEMP_CPK_X10 300
+#define EN7581_INIT_TEMP_FTK_X10 620
+#define EN7581_INIT_TEMP_NONK_X10 550
+
+#define EN7581_SCU_THERMAL_PROTECT_KEY 0x12
+#define EN7581_SCU_THERMAL_MUX_DIODE1 0x7
+
+/* Start using thermal helper only after tz are init */
+#define AIROHA_GET_SLOPE(priv) ((priv)->init_done ? \
+ thermal_zone_get_slope((priv)->tz) : \
+ (priv)->default_slope)
+#define AIROHA_GET_OFFSET(priv) ((priv)->init_done ? \
+ thermal_zone_get_offset((priv)->tz) : \
+ (priv)->default_offset)
+
+/* Convert temp to raw value as read from ADC ((((temp / 100) - init) * slope) / 1000) + offset */
+#define TEMP_TO_RAW(priv, temp) ((((((temp) / 100) - (priv)->init_temp) * \
+ AIROHA_GET_SLOPE(priv)) / 1000) + AIROHA_GET_OFFSET(priv))
+
+/* Convert raw to temp ((((temp - offset) * 1000) / slope + init) * 100) */
+#define RAW_TO_TEMP(priv, raw) (((((raw) - AIROHA_GET_OFFSET(priv)) * 1000) / \
+ AIROHA_GET_SLOPE(priv) + (priv)->init_temp) * 100)
+
+struct airoha_thermal_priv {
+ struct thermal_zone_device *tz;
+ void __iomem *base;
+
+ struct regmap *chip_scu;
+ struct resource scu_adc_res;
+ int init_temp;
+ int default_slope;
+ int default_offset;
+
+ bool init_done;
+};
+
+static int airoha_get_thermal_ADC(struct airoha_thermal_priv *priv)
+{
+ u32 val;
+
+ regmap_read(priv->chip_scu, EN7581_DOUT_TADC, &val);
+ return FIELD_GET(EN7581_DOUT_TADC_MASK, val);
+}
+
+static void airoha_init_thermal_ADC_mode(struct airoha_thermal_priv *priv)
+{
+ u32 adc_mux, pllrg;
+
+ /* Save PLLRG current value */
+ regmap_read(priv->chip_scu, EN7581_PLLRG_PROTECT, &pllrg);
+
+ /* Give access to thermal regs */
+ regmap_write(priv->chip_scu, EN7581_PLLRG_PROTECT, EN7581_SCU_THERMAL_PROTECT_KEY);
+ adc_mux = FIELD_PREP(EN7581_MUX_TADC, EN7581_SCU_THERMAL_MUX_DIODE1);
+ regmap_write(priv->chip_scu, EN7581_PWD_TADC, adc_mux);
+
+ /* Restore PLLRG value on exit */
+ regmap_write(priv->chip_scu, EN7581_PLLRG_PROTECT, pllrg);
+}
+
+static int airoha_thermal_get_temp(struct thermal_zone_device *tz, int *temp)
+{
+ struct airoha_thermal_priv *priv = tz->devdata;
+ int min, max, avg_temp, temp_adc;
+ int i;
+
+ /* Get the starting temp */
+ temp_adc = airoha_get_thermal_ADC(priv);
+ min = temp_adc;
+ max = temp_adc;
+ avg_temp = temp_adc;
+
+ /* Make 5 more measurement and average the temp ADC difference */
+ for (i = 0; i < 5; i++) {
+ temp_adc = airoha_get_thermal_ADC(priv);
+ avg_temp += temp_adc;
+ if (temp_adc > max)
+ max = temp_adc;
+ if (temp_adc < min)
+ min = temp_adc;
+ }
+ avg_temp = avg_temp - max - min;
+ avg_temp /= 4;
+
+ *temp = RAW_TO_TEMP(priv, avg_temp);
+ return 0;
+}
+
+static int airoha_thermal_set_trips(struct thermal_zone_device *tz, int low,
+ int high)
+{
+ struct airoha_thermal_priv *priv = tz->devdata;
+
+ if (high != INT_MAX) {
+ /* Validate high and clamp them a sane value */
+ if (high > RAW_TO_TEMP(priv, FIELD_MAX(EN7581_DOUT_TADC_MASK)))
+ high = 110000;
+
+ /* We offset the high temp of 1°C to trigger correct event */
+ writel(TEMP_TO_RAW(priv, high) >> 4,
+ priv->base + EN7581_TEMPOFFSETH);
+ }
+
+ if (low != -INT_MAX) {
+ /* Validate low and clamp them to a sane value */
+ if (low < RAW_TO_TEMP(priv, 0))
+ low = -33000;
+
+ /* We offset the low temp of 1°C to trigger correct event */
+ writel(TEMP_TO_RAW(priv, low) >> 4,
+ priv->base + EN7581_TEMPOFFSETL);
+ }
+
+ /* Enable sensor 0 monitor */
+ writel(EN7581_SENSE0_EN, priv->base + EN7581_TEMPMONCTL0);
+
+ return 0;
+}
+
+static const struct thermal_zone_device_ops thdev_ops = {
+ .get_temp = airoha_thermal_get_temp,
+ .set_trips = airoha_thermal_set_trips,
+};
+
+static irqreturn_t airoha_thermal_irq(int irq, void *data)
+{
+ struct airoha_thermal_priv *priv = data;
+ enum thermal_notify_event event;
+ u32 status;
+
+ status = readl(priv->base + EN7581_TEMPMONINTSTS);
+ switch (status & (EN7581_HOFSINTSTS0 | EN7581_LOFSINTSTS0)) {
+ case EN7581_HOFSINTSTS0:
+ event = THERMAL_TRIP_VIOLATED;
+ break;
+ case EN7581_LOFSINTSTS0:
+ event = THERMAL_EVENT_UNSPECIFIED;
+ break;
+ default:
+ goto exit;
+ }
+
+ thermal_zone_device_update(priv->tz, event);
+
+exit:
+ /* reset interrupt */
+ writel(status, priv->base + EN7581_TEMPMONINTSTS);
+
+ return IRQ_HANDLED;
+}
+
+static void airoha_thermal_setup_adc_val(struct device *dev,
+ struct airoha_thermal_priv *priv)
+{
+ u32 efuse_calib_info, cpu_sensor;
+
+ /* Setup thermal sensor to ADC mode and setup the mux to DIODE1 */
+ airoha_init_thermal_ADC_mode(priv);
+ /* sleep 10 ms for ADC to enable */
+ usleep_range(10 * USEC_PER_MSEC, 11 * USEC_PER_MSEC);
+
+ efuse_calib_info = readl(priv->base + EN7581_EFUSE_TEMP_OFFSET_REG);
+ if (efuse_calib_info) {
+ priv->default_offset = FIELD_GET(EN7581_EFUSE_TEMP_OFFSET, efuse_calib_info);
+ /* Different slope are applied if the sensor is used for CPU or for package */
+ cpu_sensor = readl(priv->base + EN7581_EFUSE_TEMP_CPU_SENSOR_REG);
+ if (cpu_sensor) {
+ priv->default_slope = EN7581_SLOPE_X100_DIO_DEFAULT;
+ priv->init_temp = EN7581_INIT_TEMP_FTK_X10;
+ } else {
+ priv->default_slope = EN7581_SLOPE_X100_DIO_AVS;
+ priv->init_temp = EN7581_INIT_TEMP_CPK_X10;
+ }
+ } else {
+ priv->default_offset = airoha_get_thermal_ADC(priv);
+ priv->default_slope = EN7581_SLOPE_X100_DIO_DEFAULT;
+ priv->init_temp = EN7581_INIT_TEMP_NONK_X10;
+ dev_info(dev, "missing thermal calibrarion EFUSE, using non calibrated value\n");
+ }
+}
+
+static void airoha_thermal_setup_monitor(struct airoha_thermal_priv *priv)
+{
+ /* Set measure mode */
+ writel(FIELD_PREP(EN7581_MSRCTL0, EN7581_MSRCTL_6SAMPLE_MAX_MIX_AVG4),
+ priv->base + EN7581_TEMPMSRCTL0);
+
+ /*
+ * Configure ADC valid reading addr
+ * The AHB temp monitor system doesn't have direct access to the
+ * thermal sensor. It does instead work by providing all kind of
+ * address to configure how to access and setup an ADC for the
+ * sensor. EN7581 supports only one sensor hence the
+ * implementation is greatly simplified but the AHB supports
+ * up to 4 different sensor from the same ADC that can be
+ * switched by tuning the ADC mux or wiriting address.
+ *
+ * We set valid instead of volt as we don't enable valid/volt
+ * split reading and AHB read valid addr in such case.
+ */
+ writel(priv->scu_adc_res.start + EN7581_DOUT_TADC,
+ priv->base + EN7581_TEMPADCVALIDADDR);
+
+ /*
+ * Configure valid bit on a fake value of bit 16. The ADC outputs
+ * max of 2 bytes for voltage.
+ */
+ writel(FIELD_PREP(EN7581_ADV_RD_VALID_POS, 16),
+ priv->base + EN7581_TEMPADCVALIDMASK);
+
+ /*
+ * AHB supports max 12 bytes for ADC voltage. Shift the read
+ * value 4 bit to the right. Precision lost by this is minimal
+ * in the order of half a °C and is acceptable in the context
+ * of triggering interrupt in critical condition.
+ */
+ writel(FIELD_PREP(EN7581_ADC_VOLTAGE_SHIFT, 4),
+ priv->base + EN7581_TEMPADCVOLTAGESHIFT);
+
+ /* Enable LOW and HIGH interrupt */
+ writel(EN7581_HOFSINTEN0 | EN7581_LOFSINTEN0,
+ priv->base + EN7581_TEMPMONINT);
+
+ /* BUS clock is 300MHz counting unit is 3 * 68.64 * 256 = 52.715us */
+ writel(FIELD_PREP(EN7581_PERIOD_UNIT, 3),
+ priv->base + EN7581_TEMPMONCTL1);
+
+ /*
+ * filt interval is 1 * 52.715us = 52.715us,
+ * sen interval is 379 * 52.715us = 19.97ms
+ */
+ writel(FIELD_PREP(EN7581_FILT_INTERVAL, 1) |
+ FIELD_PREP(EN7581_FILT_INTERVAL, 379),
+ priv->base + EN7581_TEMPMONCTL2);
+
+ /* AHB poll is set to 146 * 68.64 = 10.02us */
+ writel(FIELD_PREP(EN7581_ADC_POLL_INTVL, 146),
+ priv->base + EN7581_TEMPAHBPOLL);
+}
+
+static int airoha_thermal_probe(struct platform_device *pdev)
+{
+ struct airoha_thermal_priv *priv;
+ struct device_node *chip_scu_np;
+ struct device *dev = &pdev->dev;
+ int irq, ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+
+ chip_scu_np = of_parse_phandle(dev->of_node, "airoha,chip-scu", 0);
+ if (!chip_scu_np)
+ return -EINVAL;
+
+ priv->chip_scu = syscon_node_to_regmap(chip_scu_np);
+ if (IS_ERR(priv->chip_scu))
+ return PTR_ERR(priv->chip_scu);
+
+ of_address_to_resource(chip_scu_np, 0, &priv->scu_adc_res);
+ of_node_put(chip_scu_np);
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
+ airoha_thermal_irq, IRQF_ONESHOT,
+ pdev->name, (void *)priv);
+ if (ret) {
+ dev_err(dev, "Can't get interrupt working.\n");
+ return ret;
+ }
+
+ airoha_thermal_setup_monitor(priv);
+ airoha_thermal_setup_adc_val(dev, priv);
+
+ /* register of thermal sensor and get info from DT */
+ priv->tz = devm_thermal_of_zone_register(dev, 0, priv, &thdev_ops);
+ if (IS_ERR(priv->tz)) {
+ dev_err(dev, "register thermal zone sensor failed\n");
+ return PTR_ERR(priv->tz);
+ }
+
+ /* Fill tz slope and offset with parsed values */
+ priv->tz->tzp->offset = priv->default_offset;
+ priv->tz->tzp->slope = priv->default_slope;
+ priv->init_done = true;
+
+ platform_set_drvdata(pdev, priv);
+
+ return 0;
+}
+
+static const struct of_device_id airoha_thermal_match[] = {
+ { .compatible = "airoha,en7581-thermal" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, airoha_thermal_match);
+
+static struct platform_driver airoha_thermal_driver = {
+ .driver = {
+ .name = "airoha-thermal",
+ .of_match_table = airoha_thermal_match,
+ },
+ .probe = airoha_thermal_probe,
+};
+
+module_platform_driver(airoha_thermal_driver);
+
+MODULE_AUTHOR("Christian Marangi <ansuelsmth@xxxxxxxxx>");
+MODULE_DESCRIPTION("Airoha thermal driver");
+MODULE_LICENSE("GPL");
--
2.45.2
