[PATCH 2/2] thermal: amlogic: Add support for A9 thermal controller

[Xianwei Zhao via B4 Relay <devnull+xianwei.zhao.amlogic.com@kernel.org>]

From: Xianwei Zhao <xianwei.zhao@amlogic.com>

Add support for the Amlogic A9 thermal controller.

The A9 thermal controller uses different calibration parameters, requires
separate core and bus clocks, and supports a hardware over-temperature
reset mechanism.

Add the A9 calibration data, retrieve the clocks by name, and configure
the hardware reset temperature through the optional 'amlogic,hw-reset-temp'
DT property. When the property is absent, use the default reset temperature
of 110°C.

Also restore the hardware reset configuration after resume.

Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
---
 drivers/thermal/amlogic_thermal.c | 107 ++++++++++++++++++++++++++++++++++++--
 1 file changed, 104 insertions(+), 3 deletions(-)

diff --git a/drivers/thermal/amlogic_thermal.c b/drivers/thermal/amlogic_thermal.c
index a0b530624b60..c9c351496653 100644
--- a/drivers/thermal/amlogic_thermal.c
+++ b/drivers/thermal/amlogic_thermal.c
@@ -45,6 +45,18 @@
 		 TSENSOR_CFG_REG1_DEM_EN |	\
 		 TSENSOR_CFG_REG1_CH_SEL)
 
+#define TSENSOR_CFG_REG2			0x8
+	#define TSENSOR_CFG_REG2_HITEMP_EN	BIT(31)
+	#define TSENSOR_CFG_REG2_REBOOT_EN	BIT(30)
+	#define TSENSOR_CFG_REG2_REBOOT_CODE	GENMASK(15, 4)
+	#define TSENSOR_CFG_REG2_REBOOT_TIME	GENMASK(23, 16)
+	#define TSENSOR_CFG_REG2_ENABLE		\
+		(TSENSOR_CFG_REG2_HITEMP_EN |	\
+		 TSENSOR_CFG_REG2_REBOOT_EN |	\
+		 TSENSOR_CFG_REG2_REBOOT_TIME)
+
+#define TSENSOR_TEMP_CAL		1
+
 #define TSENSOR_STAT0			0x40
 
 #define TSENSOR_STAT9			0x64
@@ -63,6 +75,7 @@
 
 #define TSENSOR_CALIB_OFFSET	1
 #define TSENSOR_CALIB_SHIFT	4
+#define TSENSOR_HW_RESET_DEFAULT_TEMP	110000
 
 /**
  * struct amlogic_thermal_soc_calib_data
@@ -93,6 +106,7 @@ struct amlogic_thermal_data {
 	const struct amlogic_thermal_soc_calib_data *calibration_parameters;
 	const struct regmap_config *regmap_config;
 	bool use_sm;
+	bool has_sysclk;
 };
 
 struct amlogic_thermal {
@@ -101,8 +115,10 @@ struct amlogic_thermal {
 	struct regmap *regmap;
 	struct regmap *sec_ao_map;
 	struct clk *clk;
+	struct clk *sysclk;
 	struct thermal_zone_device *tzd;
 	u32 trim_info;
+	u32 temp_code;
 	struct meson_sm_firmware *sm_fw;
 	u32 tsensor_id;
 };
@@ -138,6 +154,46 @@ static int amlogic_thermal_code_to_millicelsius(struct amlogic_thermal *pdata,
 	return temp;
 }
 
+/*
+ * Calculate a temperature code from a temperature value .
+ * The unit of the temperature is degree milliCelsius.
+ */
+static u32 amlogic_thermal_millicelsius_to_code(struct amlogic_thermal *pdata, int millicelsius)
+{
+	const struct amlogic_thermal_soc_calib_data *param =
+					pdata->data->calibration_parameters;
+	s64 factor, uptat, uefuse;
+	u32 temp_code;
+
+	uefuse = pdata->trim_info & TSENSOR_TRIM_SIGN_MASK ?
+			     ~(pdata->trim_info & TSENSOR_TRIM_TEMP_MASK) + 1 :
+			     (pdata->trim_info & TSENSOR_TRIM_TEMP_MASK);
+
+	factor = param->B + div_s64(millicelsius, 100);
+	factor = BIT(16) * factor;
+	factor = div_s64(factor, param->A);
+	factor = factor - (uefuse & TSENSOR_TRIM_TEMP_MASK);
+
+	uptat = param->n * factor;
+	uptat = div_s64(uptat, BIT(16));
+	uptat = param->m - uptat;
+
+	factor = factor * 100;
+	factor = div_s64(factor, uptat);
+
+	temp_code = ((factor >> 0x4) & TSENSOR_TEMP_MASK) + TSENSOR_TEMP_CAL;
+
+	return temp_code;
+}
+
+static void amlogic_tsensor_setup_hw_reset(struct amlogic_thermal *data)
+{
+	regmap_update_bits(data->regmap, TSENSOR_CFG_REG2, TSENSOR_CFG_REG2_REBOOT_CODE,
+			   data->temp_code << 0x4);
+	regmap_update_bits(data->regmap, TSENSOR_CFG_REG2,
+			   TSENSOR_CFG_REG2_ENABLE, TSENSOR_CFG_REG2_ENABLE);
+}
+
 static int amlogic_thermal_enable(struct amlogic_thermal *data)
 {
 	int ret;
@@ -254,6 +310,13 @@ static const struct amlogic_thermal_soc_calib_data amlogic_thermal_g12a = {
 	.n = 324,
 };
 
+static const struct amlogic_thermal_soc_calib_data amlogic_thermal_a9 = {
+	.A = 9164,
+	.B = 2747,
+	.m = 370,
+	.n = 270,
+};
+
 static const struct amlogic_thermal_data amlogic_thermal_g12a_cpu_param = {
 	.u_efuse_off = 0x128,
 	.calibration_parameters = &amlogic_thermal_g12a,
@@ -272,6 +335,13 @@ static const struct amlogic_thermal_data amlogic_thermal_a1_cpu_param = {
 	.regmap_config = &amlogic_thermal_regmap_config_g12a,
 };
 
+static const struct amlogic_thermal_data amlogic_thermal_a9_param = {
+	.use_sm			= true,
+	.has_sysclk		= true,
+	.calibration_parameters	= &amlogic_thermal_a9,
+	.regmap_config		= &amlogic_thermal_regmap_config_g12a,
+};
+
 static const struct amlogic_thermal_data amlogic_thermal_t7_param = {
 	.use_sm			= true,
 	.calibration_parameters	= &amlogic_thermal_g12a,
@@ -291,6 +361,10 @@ static const struct of_device_id of_amlogic_thermal_match[] = {
 		.compatible = "amlogic,a1-cpu-thermal",
 		.data = &amlogic_thermal_a1_cpu_param,
 	},
+	{
+		.compatible = "amlogic,a9-thermal",
+		.data = &amlogic_thermal_a9_param,
+	},
 	{
 		.compatible = "amlogic,t7-thermal",
 		.data = &amlogic_thermal_t7_param,
@@ -305,6 +379,7 @@ static int amlogic_thermal_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	void __iomem *base;
 	int ret;
+	u32 reset_temp;
 
 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 	if (!pdata)
@@ -323,9 +398,24 @@ static int amlogic_thermal_probe(struct platform_device *pdev)
 	if (IS_ERR(pdata->regmap))
 		return PTR_ERR(pdata->regmap);
 
-	pdata->clk = devm_clk_get(dev, NULL);
-	if (IS_ERR(pdata->clk))
-		return dev_err_probe(dev, PTR_ERR(pdata->clk), "failed to get clock\n");
+	if (pdata->data->has_sysclk) {
+		pdata->clk = devm_clk_get(dev, "core");
+		if (IS_ERR(pdata->clk))
+			return dev_err_probe(dev, PTR_ERR(pdata->clk), "failed to get core clk\n");
+		pdata->sysclk = devm_clk_get_enabled(dev, "pclk");
+		if (IS_ERR(pdata->sysclk))
+			return dev_err_probe(dev, PTR_ERR(pdata->sysclk), "failed to get pclk\n");
+	} else {
+		pdata->clk = devm_clk_get(dev, NULL);
+		if (IS_ERR(pdata->clk))
+			return dev_err_probe(dev, PTR_ERR(pdata->clk), "failed to get clock\n");
+	}
+
+	if (of_property_read_u32(pdev->dev.of_node, "amlogic,hw-reset-temp", &reset_temp)) {
+		dev_dbg(dev, "using default hardware reset temperature\n");
+		reset_temp = TSENSOR_HW_RESET_DEFAULT_TEMP;
+	}
+
 
 	if (pdata->data->use_sm)
 		ret = amlogic_thermal_probe_sm(pdev, pdata);
@@ -346,6 +436,10 @@ static int amlogic_thermal_probe(struct platform_device *pdev)
 
 	devm_thermal_add_hwmon_sysfs(&pdev->dev, pdata->tzd);
 
+	pdata->temp_code = amlogic_thermal_millicelsius_to_code(pdata, reset_temp);
+
+	amlogic_tsensor_setup_hw_reset(pdata);
+
 	ret = amlogic_thermal_enable(pdata);
 
 	return ret;
@@ -355,6 +449,8 @@ static void amlogic_thermal_remove(struct platform_device *pdev)
 {
 	struct amlogic_thermal *data = platform_get_drvdata(pdev);
 
+	if (data->data->has_sysclk)
+		clk_disable_unprepare(data->sysclk);
 	amlogic_thermal_disable(data);
 }
 
@@ -363,6 +459,8 @@ static int amlogic_thermal_suspend(struct device *dev)
 	struct amlogic_thermal *data = dev_get_drvdata(dev);
 
 	amlogic_thermal_disable(data);
+	if (data->data->has_sysclk)
+		clk_disable_unprepare(data->sysclk);
 
 	return 0;
 }
@@ -371,6 +469,9 @@ static int amlogic_thermal_resume(struct device *dev)
 {
 	struct amlogic_thermal *data = dev_get_drvdata(dev);
 
+	amlogic_tsensor_setup_hw_reset(data);
+	if (data->data->has_sysclk)
+		clk_prepare_enable(data->sysclk);
 	return amlogic_thermal_enable(data);
 }
 

-- 
2.52.0