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-rw-r--r--drivers/thermal/mediatek/Kconfig16
-rw-r--r--drivers/thermal/mediatek/Makefile1
-rw-r--r--drivers/thermal/mediatek/lvts_thermal.c1224
3 files changed, 1241 insertions, 0 deletions
diff --git a/drivers/thermal/mediatek/Kconfig b/drivers/thermal/mediatek/Kconfig
index 7558a847d4e9..d82c86d9be56 100644
--- a/drivers/thermal/mediatek/Kconfig
+++ b/drivers/thermal/mediatek/Kconfig
@@ -18,4 +18,20 @@ config MTK_SOC_THERMAL
This driver configures thermal controllers to collect
temperature via AUXADC interface.
+config MTK_LVTS_THERMAL
+ tristate "LVTS Thermal Driver for MediaTek SoCs"
+ depends on HAS_IOMEM
+ help
+ Enable this option if you want to get SoC temperature
+ information for supported MediaTek platforms.
+ This driver configures LVTS (Low Voltage Thermal Sensor)
+ thermal controllers to collect temperatures via ASIF
+ (Analog Serial Interface).
+
+config MTK_LVTS_THERMAL_DEBUGFS
+ bool "LVTS thermal debugfs"
+ depends on MTK_LVTS_THERMAL && DEBUG_FS
+ help
+ Enable this option to debug the internals of the device driver.
+
endif
diff --git a/drivers/thermal/mediatek/Makefile b/drivers/thermal/mediatek/Makefile
index 53e86e30b26f..1c6daa1e644b 100644
--- a/drivers/thermal/mediatek/Makefile
+++ b/drivers/thermal/mediatek/Makefile
@@ -1 +1,2 @@
obj-$(CONFIG_MTK_SOC_THERMAL) += auxadc_thermal.o
+obj-$(CONFIG_MTK_LVTS_THERMAL) += lvts_thermal.o
diff --git a/drivers/thermal/mediatek/lvts_thermal.c b/drivers/thermal/mediatek/lvts_thermal.c
new file mode 100644
index 000000000000..84ba65a27acf
--- /dev/null
+++ b/drivers/thermal/mediatek/lvts_thermal.c
@@ -0,0 +1,1224 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2023 MediaTek Inc.
+ * Author: Balsam CHIHI <bchihi@baylibre.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/debugfs.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/thermal.h>
+#include <dt-bindings/thermal/mediatek,lvts-thermal.h>
+
+#define LVTS_MONCTL0(__base) (__base + 0x0000)
+#define LVTS_MONCTL1(__base) (__base + 0x0004)
+#define LVTS_MONCTL2(__base) (__base + 0x0008)
+#define LVTS_MONINT(__base) (__base + 0x000C)
+#define LVTS_MONINTSTS(__base) (__base + 0x0010)
+#define LVTS_MONIDET0(__base) (__base + 0x0014)
+#define LVTS_MONIDET1(__base) (__base + 0x0018)
+#define LVTS_MONIDET2(__base) (__base + 0x001C)
+#define LVTS_MONIDET3(__base) (__base + 0x0020)
+#define LVTS_H2NTHRE(__base) (__base + 0x0024)
+#define LVTS_HTHRE(__base) (__base + 0x0028)
+#define LVTS_OFFSETH(__base) (__base + 0x0030)
+#define LVTS_OFFSETL(__base) (__base + 0x0034)
+#define LVTS_MSRCTL0(__base) (__base + 0x0038)
+#define LVTS_MSRCTL1(__base) (__base + 0x003C)
+#define LVTS_TSSEL(__base) (__base + 0x0040)
+#define LVTS_CALSCALE(__base) (__base + 0x0048)
+#define LVTS_ID(__base) (__base + 0x004C)
+#define LVTS_CONFIG(__base) (__base + 0x0050)
+#define LVTS_EDATA00(__base) (__base + 0x0054)
+#define LVTS_EDATA01(__base) (__base + 0x0058)
+#define LVTS_EDATA02(__base) (__base + 0x005C)
+#define LVTS_EDATA03(__base) (__base + 0x0060)
+#define LVTS_MSR0(__base) (__base + 0x0090)
+#define LVTS_MSR1(__base) (__base + 0x0094)
+#define LVTS_MSR2(__base) (__base + 0x0098)
+#define LVTS_MSR3(__base) (__base + 0x009C)
+#define LVTS_IMMD0(__base) (__base + 0x00A0)
+#define LVTS_IMMD1(__base) (__base + 0x00A4)
+#define LVTS_IMMD2(__base) (__base + 0x00A8)
+#define LVTS_IMMD3(__base) (__base + 0x00AC)
+#define LVTS_PROTCTL(__base) (__base + 0x00C0)
+#define LVTS_PROTTA(__base) (__base + 0x00C4)
+#define LVTS_PROTTB(__base) (__base + 0x00C8)
+#define LVTS_PROTTC(__base) (__base + 0x00CC)
+#define LVTS_CLKEN(__base) (__base + 0x00E4)
+
+#define LVTS_PERIOD_UNIT ((118 * 1000) / (256 * 38))
+#define LVTS_GROUP_INTERVAL 1
+#define LVTS_FILTER_INTERVAL 1
+#define LVTS_SENSOR_INTERVAL 1
+#define LVTS_HW_FILTER 0x2
+#define LVTS_TSSEL_CONF 0x13121110
+#define LVTS_CALSCALE_CONF 0x300
+#define LVTS_MONINT_CONF 0x9FBF7BDE
+
+#define LVTS_INT_SENSOR0 0x0009001F
+#define LVTS_INT_SENSOR1 0X000881F0
+#define LVTS_INT_SENSOR2 0x00247C00
+#define LVTS_INT_SENSOR3 0x1FC00000
+
+#define LVTS_SENSOR_MAX 4
+#define LVTS_GOLDEN_TEMP_MAX 62
+#define LVTS_GOLDEN_TEMP_DEFAULT 50
+#define LVTS_COEFF_A -250460
+#define LVTS_COEFF_B 250460
+
+#define LVTS_MSR_IMMEDIATE_MODE 0
+#define LVTS_MSR_FILTERED_MODE 1
+
+#define LVTS_HW_SHUTDOWN_MT8195 105000
+
+static int golden_temp = LVTS_GOLDEN_TEMP_DEFAULT;
+static int coeff_b = LVTS_COEFF_B;
+
+struct lvts_sensor_data {
+ int dt_id;
+};
+
+struct lvts_ctrl_data {
+ struct lvts_sensor_data lvts_sensor[LVTS_SENSOR_MAX];
+ int cal_offset[LVTS_SENSOR_MAX];
+ int hw_tshut_temp;
+ int num_lvts_sensor;
+ int offset;
+ int mode;
+};
+
+struct lvts_data {
+ const struct lvts_ctrl_data *lvts_ctrl;
+ int num_lvts_ctrl;
+};
+
+struct lvts_sensor {
+ struct thermal_zone_device *tz;
+ void __iomem *msr;
+ void __iomem *base;
+ int id;
+ int dt_id;
+};
+
+struct lvts_ctrl {
+ struct lvts_sensor sensors[LVTS_SENSOR_MAX];
+ u32 calibration[LVTS_SENSOR_MAX];
+ u32 hw_tshut_raw_temp;
+ int num_lvts_sensor;
+ int mode;
+ void __iomem *base;
+};
+
+struct lvts_domain {
+ struct lvts_ctrl *lvts_ctrl;
+ struct reset_control *reset;
+ struct clk *clk;
+ int num_lvts_ctrl;
+ void __iomem *base;
+ size_t calib_len;
+ u8 *calib;
+#ifdef CONFIG_DEBUG_FS
+ struct dentry *dom_dentry;
+#endif
+};
+
+#ifdef CONFIG_MTK_LVTS_THERMAL_DEBUGFS
+
+#define LVTS_DEBUG_FS_REGS(__reg) \
+{ \
+ .name = __stringify(__reg), \
+ .offset = __reg(0), \
+}
+
+static const struct debugfs_reg32 lvts_regs[] = {
+ LVTS_DEBUG_FS_REGS(LVTS_MONCTL0),
+ LVTS_DEBUG_FS_REGS(LVTS_MONCTL1),
+ LVTS_DEBUG_FS_REGS(LVTS_MONCTL2),
+ LVTS_DEBUG_FS_REGS(LVTS_MONINT),
+ LVTS_DEBUG_FS_REGS(LVTS_MONINTSTS),
+ LVTS_DEBUG_FS_REGS(LVTS_MONIDET0),
+ LVTS_DEBUG_FS_REGS(LVTS_MONIDET1),
+ LVTS_DEBUG_FS_REGS(LVTS_MONIDET2),
+ LVTS_DEBUG_FS_REGS(LVTS_MONIDET3),
+ LVTS_DEBUG_FS_REGS(LVTS_H2NTHRE),
+ LVTS_DEBUG_FS_REGS(LVTS_HTHRE),
+ LVTS_DEBUG_FS_REGS(LVTS_OFFSETH),
+ LVTS_DEBUG_FS_REGS(LVTS_OFFSETL),
+ LVTS_DEBUG_FS_REGS(LVTS_MSRCTL0),
+ LVTS_DEBUG_FS_REGS(LVTS_MSRCTL1),
+ LVTS_DEBUG_FS_REGS(LVTS_TSSEL),
+ LVTS_DEBUG_FS_REGS(LVTS_CALSCALE),
+ LVTS_DEBUG_FS_REGS(LVTS_ID),
+ LVTS_DEBUG_FS_REGS(LVTS_CONFIG),
+ LVTS_DEBUG_FS_REGS(LVTS_EDATA00),
+ LVTS_DEBUG_FS_REGS(LVTS_EDATA01),
+ LVTS_DEBUG_FS_REGS(LVTS_EDATA02),
+ LVTS_DEBUG_FS_REGS(LVTS_EDATA03),
+ LVTS_DEBUG_FS_REGS(LVTS_MSR0),
+ LVTS_DEBUG_FS_REGS(LVTS_MSR1),
+ LVTS_DEBUG_FS_REGS(LVTS_MSR2),
+ LVTS_DEBUG_FS_REGS(LVTS_MSR3),
+ LVTS_DEBUG_FS_REGS(LVTS_IMMD0),
+ LVTS_DEBUG_FS_REGS(LVTS_IMMD1),
+ LVTS_DEBUG_FS_REGS(LVTS_IMMD2),
+ LVTS_DEBUG_FS_REGS(LVTS_IMMD3),
+ LVTS_DEBUG_FS_REGS(LVTS_PROTCTL),
+ LVTS_DEBUG_FS_REGS(LVTS_PROTTA),
+ LVTS_DEBUG_FS_REGS(LVTS_PROTTB),
+ LVTS_DEBUG_FS_REGS(LVTS_PROTTC),
+ LVTS_DEBUG_FS_REGS(LVTS_CLKEN),
+};
+
+static int lvts_debugfs_init(struct device *dev, struct lvts_domain *lvts_td)
+{
+ struct debugfs_regset32 *regset;
+ struct lvts_ctrl *lvts_ctrl;
+ struct dentry *dentry;
+ char name[64];
+ int i;
+
+ lvts_td->dom_dentry = debugfs_create_dir(dev_name(dev), NULL);
+ if (!lvts_td->dom_dentry)
+ return 0;
+
+ for (i = 0; i < lvts_td->num_lvts_ctrl; i++) {
+
+ lvts_ctrl = &lvts_td->lvts_ctrl[i];
+
+ sprintf(name, "controller%d", i);
+ dentry = debugfs_create_dir(name, lvts_td->dom_dentry);
+ if (!dentry)
+ continue;
+
+ regset = devm_kzalloc(dev, sizeof(*regset), GFP_KERNEL);
+ if (!regset)
+ continue;
+
+ regset->base = lvts_ctrl->base;
+ regset->regs = lvts_regs;
+ regset->nregs = ARRAY_SIZE(lvts_regs);
+
+ debugfs_create_regset32("registers", 0400, dentry, regset);
+ }
+
+ return 0;
+}
+
+static void lvts_debugfs_exit(struct lvts_domain *lvts_td)
+{
+ debugfs_remove_recursive(lvts_td->dom_dentry);
+}
+
+#else
+
+static inline int lvts_debugfs_init(struct device *dev,
+ struct lvts_domain *lvts_td)
+{
+ return 0;
+}
+
+static void lvts_debugfs_exit(struct lvts_domain *lvts_td) { }
+
+#endif
+
+static int lvts_raw_to_temp(u32 raw_temp)
+{
+ int temperature;
+
+ temperature = ((s64)(raw_temp & 0xFFFF) * LVTS_COEFF_A) >> 14;
+ temperature += coeff_b;
+
+ return temperature;
+}
+
+static u32 lvts_temp_to_raw(int temperature)
+{
+ u32 raw_temp = ((s64)(coeff_b - temperature)) << 14;
+
+ raw_temp = div_s64(raw_temp, -LVTS_COEFF_A);
+
+ return raw_temp;
+}
+
+static int lvts_get_temp(struct thermal_zone_device *tz, int *temp)
+{
+ struct lvts_sensor *lvts_sensor = tz->devdata;
+ void __iomem *msr = lvts_sensor->msr;
+ u32 value;
+
+ /*
+ * Measurement registers:
+ *
+ * LVTS_MSR[0-3] / LVTS_IMMD[0-3]
+ *
+ * Bits:
+ *
+ * 32-17: Unused
+ * 16 : Valid temperature
+ * 15-0 : Raw temperature
+ */
+ value = readl(msr);
+
+ /*
+ * As the thermal zone temperature will read before the
+ * hardware sensor is fully initialized, we have to check the
+ * validity of the temperature returned when reading the
+ * measurement register. The thermal controller will set the
+ * valid bit temperature only when it is totally initialized.
+ *
+ * Otherwise, we may end up with garbage values out of the
+ * functionning temperature and directly jump to a system
+ * shutdown.
+ */
+ if (!(value & BIT(16)))
+ return -EAGAIN;
+
+ *temp = lvts_raw_to_temp(value & 0xFFFF);
+
+ return 0;
+}
+
+static int lvts_set_trips(struct thermal_zone_device *tz, int low, int high)
+{
+ struct lvts_sensor *lvts_sensor = tz->devdata;
+ void __iomem *base = lvts_sensor->base;
+ u32 raw_low = lvts_temp_to_raw(low);
+ u32 raw_high = lvts_temp_to_raw(high);
+
+ /*
+ * Hot to normal temperature threshold
+ *
+ * LVTS_H2NTHRE
+ *
+ * Bits:
+ *
+ * 14-0 : Raw temperature for threshold
+ */
+ if (low != -INT_MAX) {
+ dev_dbg(&tz->device, "Setting low limit temperature interrupt: %d\n", low);
+ writel(raw_low, LVTS_H2NTHRE(base));
+ }
+
+ /*
+ * Hot temperature threshold
+ *
+ * LVTS_HTHRE
+ *
+ * Bits:
+ *
+ * 14-0 : Raw temperature for threshold
+ */
+ dev_dbg(&tz->device, "Setting high limit temperature interrupt: %d\n", high);
+ writel(raw_high, LVTS_HTHRE(base));
+
+ return 0;
+}
+
+static irqreturn_t lvts_ctrl_irq_handler(struct lvts_ctrl *lvts_ctrl)
+{
+ irqreturn_t iret = IRQ_NONE;
+ u32 value;
+ u32 masks[] = {
+ LVTS_INT_SENSOR0,
+ LVTS_INT_SENSOR1,
+ LVTS_INT_SENSOR2,
+ LVTS_INT_SENSOR3
+ };
+ int i;
+
+ /*
+ * Interrupt monitoring status
+ *
+ * LVTS_MONINTST
+ *
+ * Bits:
+ *
+ * 31 : Interrupt for stage 3
+ * 30 : Interrupt for stage 2
+ * 29 : Interrupt for state 1
+ * 28 : Interrupt using filter on sensor 3
+ *
+ * 27 : Interrupt using immediate on sensor 3
+ * 26 : Interrupt normal to hot on sensor 3
+ * 25 : Interrupt high offset on sensor 3
+ * 24 : Interrupt low offset on sensor 3
+ *
+ * 23 : Interrupt hot threshold on sensor 3
+ * 22 : Interrupt cold threshold on sensor 3
+ * 21 : Interrupt using filter on sensor 2
+ * 20 : Interrupt using filter on sensor 1
+ *
+ * 19 : Interrupt using filter on sensor 0
+ * 18 : Interrupt using immediate on sensor 2
+ * 17 : Interrupt using immediate on sensor 1
+ * 16 : Interrupt using immediate on sensor 0
+ *
+ * 15 : Interrupt device access timeout interrupt
+ * 14 : Interrupt normal to hot on sensor 2
+ * 13 : Interrupt high offset interrupt on sensor 2
+ * 12 : Interrupt low offset interrupt on sensor 2
+ *
+ * 11 : Interrupt hot threshold on sensor 2
+ * 10 : Interrupt cold threshold on sensor 2
+ * 9 : Interrupt normal to hot on sensor 1
+ * 8 : Interrupt high offset interrupt on sensor 1
+ *
+ * 7 : Interrupt low offset interrupt on sensor 1
+ * 6 : Interrupt hot threshold on sensor 1
+ * 5 : Interrupt cold threshold on sensor 1
+ * 4 : Interrupt normal to hot on sensor 0
+ *
+ * 3 : Interrupt high offset interrupt on sensor 0
+ * 2 : Interrupt low offset interrupt on sensor 0
+ * 1 : Interrupt hot threshold on sensor 0
+ * 0 : Interrupt cold threshold on sensor 0
+ *
+ * We are interested in the sensor(s) responsible of the
+ * interrupt event. We update the thermal framework with the
+ * thermal zone associated with the sensor. The framework will
+ * take care of the rest whatever the kind of interrupt, we
+ * are only interested in which sensor raised the interrupt.
+ *
+ * sensor 3 interrupt: 0001 1111 1100 0000 0000 0000 0000 0000
+ * => 0x1FC00000
+ * sensor 2 interrupt: 0000 0000 0010 0100 0111 1100 0000 0000
+ * => 0x00247C00
+ * sensor 1 interrupt: 0000 0000 0001 0001 0000 0011 1110 0000
+ * => 0X000881F0
+ * sensor 0 interrupt: 0000 0000 0000 1001 0000 0000 0001 1111
+ * => 0x0009001F
+ */
+ value = readl(LVTS_MONINTSTS(lvts_ctrl->base));
+
+ /*
+ * Let's figure out which sensors raised the interrupt
+ *
+ * NOTE: the masks array must be ordered with the index
+ * corresponding to the sensor id eg. index=0, mask for
+ * sensor0.
+ */
+ for (i = 0; i < ARRAY_SIZE(masks); i++) {
+
+ if (!(value & masks[i]))
+ continue;
+
+ thermal_zone_device_update(lvts_ctrl->sensors[i].tz,
+ THERMAL_TRIP_VIOLATED);
+ iret = IRQ_HANDLED;
+ }
+
+ /*
+ * Write back to clear the interrupt status (W1C)
+ */
+ writel(value, LVTS_MONINTSTS(lvts_ctrl->base));
+
+ return iret;
+}
+
+/*
+ * Temperature interrupt handler. Even if the driver supports more
+ * interrupt modes, we use the interrupt when the temperature crosses
+ * the hot threshold the way up and the way down (modulo the
+ * hysteresis).
+ *
+ * Each thermal domain has a couple of interrupts, one for hardware
+ * reset and another one for all the thermal events happening on the
+ * different sensors.
+ *
+ * The interrupt is configured for thermal events when crossing the
+ * hot temperature limit. At each interrupt, we check in every
+ * controller if there is an interrupt pending.
+ */
+static irqreturn_t lvts_irq_handler(int irq, void *data)
+{
+ struct lvts_domain *lvts_td = data;
+ irqreturn_t aux, iret = IRQ_NONE;
+ int i;
+
+ for (i = 0; i < lvts_td->num_lvts_ctrl; i++) {
+
+ aux = lvts_ctrl_irq_handler(lvts_td->lvts_ctrl);
+ if (aux != IRQ_HANDLED)
+ continue;
+
+ iret = IRQ_HANDLED;
+ }
+
+ return iret;
+}
+
+static struct thermal_zone_device_ops lvts_ops = {
+ .get_temp = lvts_get_temp,
+ .set_trips = lvts_set_trips,
+};
+
+static int lvts_sensor_init(struct device *dev, struct lvts_ctrl *lvts_ctrl,
+ const struct lvts_ctrl_data *lvts_ctrl_data)
+{
+ struct lvts_sensor *lvts_sensor = lvts_ctrl->sensors;
+ void __iomem *msr_regs[] = {
+ LVTS_MSR0(lvts_ctrl->base),
+ LVTS_MSR1(lvts_ctrl->base),
+ LVTS_MSR2(lvts_ctrl->base),
+ LVTS_MSR3(lvts_ctrl->base)
+ };
+
+ void __iomem *imm_regs[] = {
+ LVTS_IMMD0(lvts_ctrl->base),
+ LVTS_IMMD1(lvts_ctrl->base),
+ LVTS_IMMD2(lvts_ctrl->base),
+ LVTS_IMMD3(lvts_ctrl->base)
+ };
+
+ int i;
+
+ for (i = 0; i < lvts_ctrl_data->num_lvts_sensor; i++) {
+
+ int dt_id = lvts_ctrl_data->lvts_sensor[i].dt_id;
+
+ /*
+ * At this point, we don't know which id matches which
+ * sensor. Let's set arbitrally the id from the index.
+ */
+ lvts_sensor[i].id = i;
+
+ /*
+ * The thermal zone registration will set the trip
+ * point interrupt in the thermal controller
+ * register. But this one will be reset in the
+ * initialization after. So we need to post pone the
+ * thermal zone creation after the controller is
+ * setup. For this reason, we store the device tree
+ * node id from the data in the sensor structure
+ */
+ lvts_sensor[i].dt_id = dt_id;
+
+ /*
+ * We assign the base address of the thermal
+ * controller as a back pointer. So it will be
+ * accessible from the different thermal framework ops
+ * as we pass the lvts_sensor pointer as thermal zone
+ * private data.
+ */
+ lvts_sensor[i].base = lvts_ctrl->base;
+
+ /*
+ * Each sensor has its own register address to read from.
+ */
+ lvts_sensor[i].msr = lvts_ctrl_data->mode == LVTS_MSR_IMMEDIATE_MODE ?
+ imm_regs[i] : msr_regs[i];
+ };
+
+ lvts_ctrl->num_lvts_sensor = lvts_ctrl_data->num_lvts_sensor;
+
+ return 0;
+}
+
+/*
+ * The efuse blob values follows the sensor enumeration per thermal
+ * controller. The decoding of the stream is as follow:
+ *
+ * <--?-> <----big0 ???---> <-sensor0-> <-0->
+ * ------------------------------------------
+ * index in the stream: : | 0x0 | 0x1 | 0x2 | 0x3 | 0x4 | 0x5 | 0x6 |
+ * ------------------------------------------
+ *
+ * <--sensor1--><-0-> <----big1 ???---> <-sen
+ * ------------------------------------------
+ * | 0x7 | 0x8 | 0x9 | 0xA | 0xB | OxC | OxD |
+ * ------------------------------------------
+ *
+ * sor0-> <-0-> <-sensor1-> <-0-> ..........
+ * ------------------------------------------
+ * | 0x7 | 0x8 | 0x9 | 0xA | 0xB | OxC | OxD |
+ * ------------------------------------------
+ *
+ * And so on ...
+ *
+ * The data description gives the offset of the calibration data in
+ * this bytes stream for each sensor.
+ *
+ * Each thermal controller can handle up to 4 sensors max, we don't
+ * care if there are less as the array of calibration is sized to 4
+ * anyway. The unused sensor slot will be zeroed.
+ */
+static int lvts_calibration_init(struct device *dev, struct lvts_ctrl *lvts_ctrl,
+ const struct lvts_ctrl_data *lvts_ctrl_data,
+ u8 *efuse_calibration)
+{
+ int i;
+
+ for (i = 0; i < lvts_ctrl_data->num_lvts_sensor; i++)
+ memcpy(&lvts_ctrl->calibration[i],
+ efuse_calibration + lvts_ctrl_data->cal_offset[i], 2);
+
+ return 0;
+}
+
+/*
+ * The efuse bytes stream can be split into different chunk of
+ * nvmems. This function reads and concatenate those into a single
+ * buffer so it can be read sequentially when initializing the
+ * calibration data.
+ */
+static int lvts_calibration_read(struct device *dev, struct lvts_domain *lvts_td,
+ const struct lvts_data *lvts_data)
+{
+ struct device_node *np = dev_of_node(dev);
+ struct nvmem_cell *cell;
+ struct property *prop;
+ const char *cell_name;
+
+ of_property_for_each_string(np, "nvmem-cell-names", prop, cell_name) {
+ size_t len;
+ u8 *efuse;
+
+ cell = of_nvmem_cell_get(np, cell_name);
+ if (IS_ERR(cell)) {
+ dev_err(dev, "Failed to get cell '%s'\n", cell_name);
+ return PTR_ERR(cell);
+ }
+
+ efuse = nvmem_cell_read(cell, &len);
+
+ nvmem_cell_put(cell);
+
+ if (IS_ERR(efuse)) {
+ dev_err(dev, "Failed to read cell '%s'\n", cell_name);
+ return PTR_ERR(efuse);
+ }
+
+ lvts_td->calib = devm_krealloc(dev, lvts_td->calib,
+ lvts_td->calib_len + len, GFP_KERNEL);
+ if (!lvts_td->calib)
+ return -ENOMEM;
+
+ memcpy(lvts_td->calib + lvts_td->calib_len, efuse, len);
+
+ lvts_td->calib_len += len;
+
+ kfree(efuse);
+ }
+
+ return 0;
+}
+
+static int lvts_golden_temp_init(struct device *dev, u32 *value)
+{
+ u32 gt;
+
+ gt = (*value) >> 24;
+
+ if (gt && gt < LVTS_GOLDEN_TEMP_MAX)
+ golden_temp = gt;
+
+ coeff_b = golden_temp * 500 + LVTS_COEFF_B;
+
+ return 0;
+}
+
+static int lvts_ctrl_init(struct device *dev, struct lvts_domain *lvts_td,
+ const struct lvts_data *lvts_data)
+{
+ size_t size = sizeof(*lvts_td->lvts_ctrl) * lvts_data->num_lvts_ctrl;
+ struct lvts_ctrl *lvts_ctrl;
+ int i, ret;
+
+ /*
+ * Create the calibration bytes stream from efuse data
+ */
+ ret = lvts_calibration_read(dev, lvts_td, lvts_data);
+ if (ret)
+ return ret;
+
+ /*
+ * The golden temp information is contained in the first chunk
+ * of efuse data.
+ */
+ ret = lvts_golden_temp_init(dev, (u32 *)lvts_td->calib);
+ if (ret)
+ return ret;
+
+ lvts_ctrl = devm_kzalloc(dev, size, GFP_KERNEL);
+ if (!lvts_ctrl)
+ return -ENOMEM;
+
+ for (i = 0; i < lvts_data->num_lvts_ctrl; i++) {
+
+ lvts_ctrl[i].base = lvts_td->base + lvts_data->lvts_ctrl[i].offset;
+
+ ret = lvts_sensor_init(dev, &lvts_ctrl[i],
+ &lvts_data->lvts_ctrl[i]);
+ if (ret)
+ return ret;
+
+ ret = lvts_calibration_init(dev, &lvts_ctrl[i],
+ &lvts_data->lvts_ctrl[i],
+ lvts_td->calib);
+ if (ret)
+ return ret;
+
+ /*
+ * The mode the ctrl will use to read the temperature
+ * (filtered or immediate)
+ */
+ lvts_ctrl[i].mode = lvts_data->lvts_ctrl[i].mode;
+
+ /*
+ * The temperature to raw temperature must be done
+ * after initializing the calibration.
+ */
+ lvts_ctrl[i].hw_tshut_raw_temp =
+ lvts_temp_to_raw(lvts_data->lvts_ctrl[i].hw_tshut_temp);
+ }
+
+ /*
+ * We no longer need the efuse bytes stream, let's free it
+ */
+ devm_kfree(dev, lvts_td->calib);
+
+ lvts_td->lvts_ctrl = lvts_ctrl;
+ lvts_td->num_lvts_ctrl = lvts_data->num_lvts_ctrl;
+
+ return 0;
+}
+
+/*
+ * At this point the configuration register is the only place in the
+ * driver where we write multiple values. Per hardware constraint,
+ * each write in the configuration register must be separated by a
+ * delay of 2 us.
+ */
+static void lvts_write_config(struct lvts_ctrl *lvts_ctrl, u32 *cmds, int nr_cmds)
+{
+ int i;
+
+ /*
+ * Configuration register
+ */
+ for (i = 0; i < nr_cmds; i++) {
+ writel(cmds[i], LVTS_CONFIG(lvts_ctrl->base));
+ usleep_range(2, 4);
+ }
+}
+
+static int lvts_irq_init(struct lvts_ctrl *lvts_ctrl)
+{
+ /*
+ * LVTS_PROTCTL : Thermal Protection Sensor Selection
+ *
+ * Bits:
+ *
+ * 19-18 : Sensor to base the protection on
+ * 17-16 : Strategy:
+ * 00 : Average of 4 sensors
+ * 01 : Max of 4 sensors
+ * 10 : Selected sensor with bits 19-18
+ * 11 : Reserved
+ */
+ writel(BIT(16), LVTS_PROTCTL(lvts_ctrl->base));
+
+ /*
+ * LVTS_PROTTA : Stage 1 temperature threshold
+ * LVTS_PROTTB : Stage 2 temperature threshold
+ * LVTS_PROTTC : Stage 3 temperature threshold
+ *
+ * Bits:
+ *
+ * 14-0: Raw temperature threshold
+ *
+ * writel(0x0, LVTS_PROTTA(lvts_ctrl->base));
+ * writel(0x0, LVTS_PROTTB(lvts_ctrl->base));
+ */
+ writel(lvts_ctrl->hw_tshut_raw_temp, LVTS_PROTTC(lvts_ctrl->base));
+
+ /*
+ * LVTS_MONINT : Interrupt configuration register
+ *
+ * The LVTS_MONINT register layout is the same as the LVTS_MONINTSTS
+ * register, except we set the bits to enable the interrupt.
+ */
+ writel(LVTS_MONINT_CONF, LVTS_MONINT(lvts_ctrl->base));
+
+ return 0;
+}
+
+static int lvts_domain_reset(struct device *dev, struct reset_control *reset)
+{
+ int ret;
+
+ ret = reset_control_assert(reset);
+ if (ret)
+ return ret;
+
+ return reset_control_deassert(reset);
+}
+
+/*
+ * Enable or disable the clocks of a specified thermal controller
+ */
+static int lvts_ctrl_set_enable(struct lvts_ctrl *lvts_ctrl, int enable)
+{
+ /*
+ * LVTS_CLKEN : Internal LVTS clock
+ *
+ * Bits:
+ *
+ * 0 : enable / disable clock
+ */
+ writel(enable, LVTS_CLKEN(lvts_ctrl->base));
+
+ return 0;
+}
+
+static int lvts_ctrl_connect(struct device *dev, struct lvts_ctrl *lvts_ctrl)
+{
+ u32 id, cmds[] = { 0xC103FFFF, 0xC502FF55 };
+
+ lvts_write_config(lvts_ctrl, cmds, ARRAY_SIZE(cmds));
+
+ /*
+ * LVTS_ID : Get ID and status of the thermal controller
+ *
+ * Bits:
+ *
+ * 0-5 : thermal controller id
+ * 7 : thermal controller connection is valid
+ */
+ id = readl(LVTS_ID(lvts_ctrl->base));
+ if (!(id & BIT(7)))
+ return -EIO;
+
+ return 0;
+}
+
+static int lvts_ctrl_initialize(struct device *dev, struct lvts_ctrl *lvts_ctrl)
+{
+ /*
+ * Write device mask: 0xC1030000
+ */
+ u32 cmds[] = {
+ 0xC1030E01, 0xC1030CFC, 0xC1030A8C, 0xC103098D, 0xC10308F1,
+ 0xC10307A6, 0xC10306B8, 0xC1030500, 0xC1030420, 0xC1030300,
+ 0xC1030030, 0xC10300F6, 0xC1030050, 0xC1030060, 0xC10300AC,
+ 0xC10300FC, 0xC103009D, 0xC10300F1, 0xC10300E1
+ };
+
+ lvts_write_config(lvts_ctrl, cmds, ARRAY_SIZE(cmds));
+
+ return 0;
+}
+
+static int lvts_ctrl_calibrate(struct device *dev, struct lvts_ctrl *lvts_ctrl)
+{
+ int i;
+ void __iomem *lvts_edata[] = {
+ LVTS_EDATA00(lvts_ctrl->base),
+ LVTS_EDATA01(lvts_ctrl->base),
+ LVTS_EDATA02(lvts_ctrl->base),
+ LVTS_EDATA03(lvts_ctrl->base)
+ };
+
+ /*
+ * LVTS_EDATA0X : Efuse calibration reference value for sensor X
+ *
+ * Bits:
+ *
+ * 20-0 : Efuse value for normalization data
+ */
+ for (i = 0; i < LVTS_SENSOR_MAX; i++)
+ writel(lvts_ctrl->calibration[i], lvts_edata[i]);
+
+ return 0;
+}
+
+static int lvts_ctrl_configure(struct device *dev, struct lvts_ctrl *lvts_ctrl)
+{
+ u32 value;
+
+ /*
+ * LVTS_TSSEL : Sensing point index numbering
+ *
+ * Bits:
+ *
+ * 31-24: ADC Sense 3
+ * 23-16: ADC Sense 2
+ * 15-8 : ADC Sense 1
+ * 7-0 : ADC Sense 0
+ */
+ value = LVTS_TSSEL_CONF;
+ writel(value, LVTS_TSSEL(lvts_ctrl->base));
+
+ /*
+ * LVTS_CALSCALE : ADC voltage round
+ */
+ value = 0x300;
+ value = LVTS_CALSCALE_CONF;
+
+ /*
+ * LVTS_MSRCTL0 : Sensor filtering strategy
+ *
+ * Filters:
+ *
+ * 000 : One sample
+ * 001 : Avg 2 samples
+ * 010 : 4 samples, drop min and max, avg 2 samples
+ * 011 : 6 samples, drop min and max, avg 4 samples
+ * 100 : 10 samples, drop min and max, avg 8 samples
+ * 101 : 18 samples, drop min and max, avg 16 samples
+ *
+ * Bits:
+ *
+ * 0-2 : Sensor0 filter
+ * 3-5 : Sensor1 filter
+ * 6-8 : Sensor2 filter
+ * 9-11 : Sensor3 filter
+ */
+ value = LVTS_HW_FILTER << 9 | LVTS_HW_FILTER << 6 |
+ LVTS_HW_FILTER << 3 | LVTS_HW_FILTER;
+ writel(value, LVTS_MSRCTL0(lvts_ctrl->base));
+
+ /*
+ * LVTS_MSRCTL1 : Measurement control
+ *
+ * Bits:
+ *
+ * 9: Ignore MSRCTL0 config and do immediate measurement on sensor3
+ * 6: Ignore MSRCTL0 config and do immediate measurement on sensor2
+ * 5: Ignore MSRCTL0 config and do immediate measurement on sensor1
+ * 4: Ignore MSRCTL0 config and do immediate measurement on sensor0
+ *
+ * That configuration will ignore the filtering and the delays
+ * introduced below in MONCTL1 and MONCTL2
+ */
+ if (lvts_ctrl->mode == LVTS_MSR_IMMEDIATE_MODE) {
+ value = BIT(9) | BIT(6) | BIT(5) | BIT(4);
+ writel(value, LVTS_MSRCTL1(lvts_ctrl->base));
+ }
+
+ /*
+ * LVTS_MONCTL1 : Period unit and group interval configuration
+ *
+ * The clock source of LVTS thermal controller is 26MHz.
+ *
+ * The period unit is a time base for all the interval delays
+ * specified in the registers. By default we use 12. The time
+ * conversion is done by multiplying by 256 and 1/26.10^6
+ *
+ * An interval delay multiplied by the period unit gives the
+ * duration in seconds.
+ *
+ * - Filter interval delay is a delay between two samples of
+ * the same sensor.
+ *
+ * - Sensor interval delay is a delay between two samples of
+ * different sensors.
+ *
+ * - Group interval delay is a delay between different rounds.
+ *
+ * For example:
+ * If Period unit = C, filter delay = 1, sensor delay = 2, group delay = 1,
+ * and two sensors, TS1 and TS2, are in a LVTS thermal controller
+ * and then
+ * Period unit time = C * 1/26M * 256 = 12 * 38.46ns * 256 = 118.149us
+ * Filter interval delay = 1 * Period unit = 118.149us
+ * Sensor interval delay = 2 * Period unit = 236.298us
+ * Group interval delay = 1 * Period unit = 118.149us
+ *
+ * TS1 TS1 ... TS1 TS2 TS2 ... TS2 TS1...
+ * <--> Filter interval delay
+ * <--> Sensor interval delay
+ * <--> Group interval delay
+ * Bits:
+ * 29 - 20 : Group interval
+ * 16 - 13 : Send a single interrupt when crossing the hot threshold (1)
+ * or an interrupt everytime the hot threshold is crossed (0)
+ * 9 - 0 : Period unit
+ *
+ */
+ value = LVTS_GROUP_INTERVAL << 20 | LVTS_PERIOD_UNIT;
+ writel(value, LVTS_MONCTL1(lvts_ctrl->base));
+
+ /*
+ * LVTS_MONCTL2 : Filtering and sensor interval
+ *
+ * Bits:
+ *
+ * 25-16 : Interval unit in PERIOD_UNIT between sample on
+ * the same sensor, filter interval
+ * 9-0 : Interval unit in PERIOD_UNIT between each sensor
+ *
+ */
+ value = LVTS_FILTER_INTERVAL << 16 | LVTS_SENSOR_INTERVAL;
+ writel(value, LVTS_MONCTL2(lvts_ctrl->base));
+
+ return lvts_irq_init(lvts_ctrl);
+}
+
+static int lvts_ctrl_start(struct device *dev, struct lvts_ctrl *lvts_ctrl)
+{
+ struct lvts_sensor *lvts_sensors = lvts_ctrl->sensors;
+ struct thermal_zone_device *tz;
+ u32 sensor_map = 0;
+ int i;
+
+ for (i = 0; i < lvts_ctrl->num_lvts_sensor; i++) {
+
+ int dt_id = lvts_sensors[i].dt_id;
+
+ tz = devm_thermal_of_zone_register(dev, dt_id, &lvts_sensors[i],
+ &lvts_ops);
+ if (IS_ERR(tz)) {
+ /*
+ * This thermal zone is not described in the
+ * device tree. It is not an error from the
+ * thermal OF code POV, we just continue.
+ */
+ if (PTR_ERR(tz) == -ENODEV)
+ continue;
+
+ return PTR_ERR(tz);
+ }
+
+ /*
+ * The thermal zone pointer will be needed in the
+ * interrupt handler, we store it in the sensor
+ * structure. The thermal domain structure will be
+ * passed to the interrupt handler private data as the
+ * interrupt is shared for all the controller
+ * belonging to the thermal domain.
+ */
+ lvts_sensors[i].tz = tz;
+
+ /*
+ * This sensor was correctly associated with a thermal
+ * zone, let's set the corresponding bit in the sensor
+ * map, so we can enable the temperature monitoring in
+ * the hardware thermal controller.
+ */
+ sensor_map |= BIT(i);
+ }
+
+ /*
+ * Bits:
+ * 9: Single point access flow
+ * 0-3: Enable sensing point 0-3
+ *
+ * The initialization of the thermal zones give us
+ * which sensor point to enable. If any thermal zone
+ * was not described in the device tree, it won't be
+ * enabled here in the sensor map.
+ */
+ writel(sensor_map | BIT(9), LVTS_MONCTL0(lvts_ctrl->base));
+
+ return 0;
+}
+
+static int lvts_domain_init(struct device *dev, struct lvts_domain *lvts_td,
+ const struct lvts_data *lvts_data)
+{
+ struct lvts_ctrl *lvts_ctrl;
+ int i, ret;
+
+ ret = lvts_ctrl_init(dev, lvts_td, lvts_data);
+ if (ret)
+ return ret;
+
+ ret = lvts_domain_reset(dev, lvts_td->reset);
+ if (ret) {
+ dev_dbg(dev, "Failed to reset domain");
+ return ret;
+ }
+
+ for (i = 0; i < lvts_td->num_lvts_ctrl; i++) {
+
+ lvts_ctrl = &lvts_td->lvts_ctrl[i];
+
+ /*
+ * Initialization steps:
+ *
+ * - Enable the clock
+ * - Connect to the LVTS
+ * - Initialize the LVTS
+ * - Prepare the calibration data
+ * - Select monitored sensors
+ * [ Configure sampling ]
+ * [ Configure the interrupt ]
+ * - Start measurement
+ */
+ ret = lvts_ctrl_set_enable(lvts_ctrl, true);
+ if (ret) {
+ dev_dbg(dev, "Failed to enable LVTS clock");
+ return ret;
+ }
+
+ ret = lvts_ctrl_connect(dev, lvts_ctrl);
+ if (ret) {
+ dev_dbg(dev, "Failed to connect to LVTS controller");
+ return ret;
+ }
+
+ ret = lvts_ctrl_initialize(dev, lvts_ctrl);
+ if (ret) {
+ dev_dbg(dev, "Failed to initialize controller");
+ return ret;
+ }
+
+ ret = lvts_ctrl_calibrate(dev, lvts_ctrl);
+ if (ret) {
+ dev_dbg(dev, "Failed to calibrate controller");
+ return ret;
+ }
+
+ ret = lvts_ctrl_configure(dev, lvts_ctrl);
+ if (ret) {
+ dev_dbg(dev, "Failed to configure controller");
+ return ret;
+ }
+
+ ret = lvts_ctrl_start(dev, lvts_ctrl);
+ if (ret) {
+ dev_dbg(dev, "Failed to start controller");
+ return ret;
+ }
+ }
+
+ return lvts_debugfs_init(dev, lvts_td);
+}
+
+static int lvts_probe(struct platform_device *pdev)
+{
+ const struct lvts_data *lvts_data;
+ struct lvts_domain *lvts_td;
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ int irq, ret;
+
+ lvts_td = devm_kzalloc(dev, sizeof(*lvts_td), GFP_KERNEL);
+ if (!lvts_td)
+ return -ENOMEM;
+
+ lvts_data = of_device_get_match_data(dev);
+
+ lvts_td->clk = devm_clk_get_enabled(dev, NULL);
+ if (IS_ERR(lvts_td->clk))
+ return dev_err_probe(dev, PTR_ERR(lvts_td->clk), "Failed to retrieve clock\n");
+
+ res = platform_get_mem_or_io(pdev, 0);
+ if (!res)
+ return dev_err_probe(dev, (-ENXIO), "No IO resource\n");
+
+ lvts_td->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
+ if (IS_ERR(lvts_td->base))
+ return dev_err_probe(dev, PTR_ERR(lvts_td->base), "Failed to map io resource\n");
+
+ lvts_td->reset = devm_reset_control_get_by_index(dev, 0);
+ if (IS_ERR(lvts_td->reset))
+ return dev_err_probe(dev, PTR_ERR(lvts_td->reset), "Failed to get reset control\n");
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return dev_err_probe(dev, irq, "No irq resource\n");
+
+ ret = lvts_domain_init(dev, lvts_td, lvts_data);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to initialize the lvts domain\n");
+
+ /*
+ * At this point the LVTS is initialized and enabled. We can
+ * safely enable the interrupt.
+ */
+ ret = devm_request_threaded_irq(dev, irq, NULL, lvts_irq_handler,
+ IRQF_ONESHOT, dev_name(dev), lvts_td);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to request interrupt\n");
+
+ platform_set_drvdata(pdev, lvts_td);
+
+ return 0;
+}
+
+static int lvts_remove(struct platform_device *pdev)
+{
+ struct lvts_domain *lvts_td;
+ int i;
+
+ lvts_td = platform_get_drvdata(pdev);
+
+ for (i = 0; i < lvts_td->num_lvts_ctrl; i++)
+ lvts_ctrl_set_enable(&lvts_td->lvts_ctrl[i], false);
+
+ lvts_debugfs_exit(lvts_td);
+
+ return 0;
+}
+
+static const struct lvts_ctrl_data mt8195_lvts_data_ctrl[] = {
+ {
+ .cal_offset = { 0x04, 0x07 },
+ .lvts_sensor = {
+ { .dt_id = MT8195_MCU_BIG_CPU0 },
+ { .dt_id = MT8195_MCU_BIG_CPU1 }
+ },
+ .num_lvts_sensor = 2,
+ .offset = 0x0,
+ .hw_tshut_temp = LVTS_HW_SHUTDOWN_MT8195,
+ },
+ {
+ .cal_offset = { 0x0d, 0x10 },
+ .lvts_sensor = {
+ { .dt_id = MT8195_MCU_BIG_CPU2 },
+ { .dt_id = MT8195_MCU_BIG_CPU3 }
+ },
+ .num_lvts_sensor = 2,
+ .offset = 0x100,
+ .hw_tshut_temp = LVTS_HW_SHUTDOWN_MT8195,
+ },
+ {
+ .cal_offset = { 0x16, 0x19, 0x1c, 0x1f },
+ .lvts_sensor = {
+ { .dt_id = MT8195_MCU_LITTLE_CPU0 },
+ { .dt_id = MT8195_MCU_LITTLE_CPU1 },
+ { .dt_id = MT8195_MCU_LITTLE_CPU2 },
+ { .dt_id = MT8195_MCU_LITTLE_CPU3 }
+ },
+ .num_lvts_sensor = 4,
+ .offset = 0x200,
+ .hw_tshut_temp = LVTS_HW_SHUTDOWN_MT8195,
+ }
+};
+
+static const struct lvts_data mt8195_lvts_mcu_data = {
+ .lvts_ctrl = mt8195_lvts_data_ctrl,
+ .num_lvts_ctrl = ARRAY_SIZE(mt8195_lvts_data_ctrl),
+};
+
+static const struct of_device_id lvts_of_match[] = {
+ { .compatible = "mediatek,mt8195-lvts-mcu", .data = &mt8195_lvts_mcu_data },
+ {},
+};
+MODULE_DEVICE_TABLE(of, lvts_of_match);
+
+static struct platform_driver lvts_driver = {
+ .probe = lvts_probe,
+ .remove = lvts_remove,
+ .driver = {
+ .name = "mtk-lvts-thermal",
+ .of_match_table = lvts_of_match,
+ },
+};
+module_platform_driver(lvts_driver);
+
+MODULE_AUTHOR("Balsam CHIHI <bchihi@baylibre.com>");
+MODULE_DESCRIPTION("MediaTek LVTS Thermal Driver");
+MODULE_LICENSE("GPL");