[PATCH 2/6] thermal: amlogic: Add thermal driver to support G12 SoCs

[Guillaume La Roque <glaroque@baylibre.com>]

Signed-off-by: Guillaume La Roque <glaroque@baylibre.com>
---
 drivers/thermal/Kconfig           |  12 +-
 drivers/thermal/Makefile          |   1 +
 drivers/thermal/amlogic_thermal.c | 335 ++++++++++++++++++++++++++++++
 3 files changed, 347 insertions(+), 1 deletion(-)
 create mode 100644 drivers/thermal/amlogic_thermal.c

diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index 9966364a6deb..2332ef1bfafc 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -1,4 +1,3 @@
-# SPDX-License-Identifier: GPL-2.0-only
 #
 # Generic thermal sysfs drivers configuration
 #
@@ -348,6 +347,17 @@ config MTK_THERMAL
 	  Enable this option if you want to have support for thermal management
 	  controller present in Mediatek SoCs
 
+config AMLOGIC_THERMAL
+	tristate "Amlogic Thermal Support"
+	default ARCH_MESON
+	depends on OF && ARCH_MESON
+	help
+	  If you say yes here you get support for Amlogic Thermal
+	  for G12 SoC Family.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called amlogic_thermal.
+
 menu "Intel thermal drivers"
 depends on X86 || X86_INTEL_QUARK || COMPILE_TEST
 source "drivers/thermal/intel/Kconfig"
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 74a37c7f847a..baeb70bf0568 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -54,3 +54,4 @@ obj-$(CONFIG_MTK_THERMAL)	+= mtk_thermal.o
 obj-$(CONFIG_GENERIC_ADC_THERMAL)	+= thermal-generic-adc.o
 obj-$(CONFIG_ZX2967_THERMAL)	+= zx2967_thermal.o
 obj-$(CONFIG_UNIPHIER_THERMAL)	+= uniphier_thermal.o
+obj-$(CONFIG_AMLOGIC_THERMAL)     += amlogic_thermal.o
diff --git a/drivers/thermal/amlogic_thermal.c b/drivers/thermal/amlogic_thermal.c
new file mode 100644
index 000000000000..6b6d62326725
--- /dev/null
+++ b/drivers/thermal/amlogic_thermal.c
@@ -0,0 +1,335 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Amlogic Meson Thermal Sensor Driver
+ *
+ * Copyright (C) 2017 Huan Biao <huan.biao@amlogic.com>
+ * Copyright (C) 2019 Guillaume La Roque <glaroque@baylibre.com>
+ *
+ * Register value to celsius temperature formulas:
+ *	Read_Val	    m * U
+ * U = ---------, Uptat = ---------
+ *	2^16		  1 + n * U
+ *
+ * Temperature = A * ( Uptat + u_efuse / 2^16 )- B
+ *
+ *  A B m n : calibration parameters
+ *  u_efuse : fused calibration value, it's a signed 16 bits value
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/thermal.h>
+
+#include "thermal_core.h"
+
+#define TSENSOR_CFG_REG1			0x4
+	#define TSENSOR_CFG_REG1_RSET_VBG	BIT(12)
+	#define TSENSOR_CFG_REG1_RSET_ADC	BIT(11)
+	#define TSENSOR_CFG_REG1_VCM_EN		BIT(10)
+	#define TSENSOR_CFG_REG1_VBG_EN		BIT(9)
+	#define TSENSOR_CFG_REG1_OUT_CTL	BIT(6)
+	#define TSENSOR_CFG_REG1_FILTER_EN	BIT(5)
+	#define TSENSOR_CFG_REG1_DEM_EN		BIT(3)
+	#define TSENSOR_CFG_REG1_CH_SEL		GENMASK(1, 0)
+	#define TSENSOR_CFG_REG1_ENABLE		\
+		(TSENSOR_CFG_REG1_FILTER_EN |	\
+		 TSENSOR_CFG_REG1_VCM_EN |	\
+		 TSENSOR_CFG_REG1_VBG_EN |	\
+		 TSENSOR_CFG_REG1_DEM_EN |	\
+		 TSENSOR_CFG_REG1_CH_SEL)
+
+#define TSENSOR_STAT0			0x40
+
+#define TSENSOR_STAT9			0x64
+
+#define TSENSOR_READ_TEMP_MASK		GENMASK(15, 0)
+#define TSENSOR_TEMP_MASK		GENMASK(11, 0)
+
+#define TSENSOR_TRIM_SIGN_MASK		BIT(15)
+#define TSENSOR_TRIM_TEMP_MASK		GENMASK(14, 0)
+#define TSENSOR_TRIM_VERSION_MASK	GENMASK(31, 24)
+
+#define TSENSOR_TRIM_VERSION(_version)	\
+	FIELD_GET(TSENSOR_TRIM_VERSION_MASK, _version)
+
+#define TSENSOR_TRIM_CALIB_VALID_MASK	(GENMASK(3, 2) | BIT(7))
+
+#define TSENSOR_CALIB_OFFSET	1
+#define TSENSOR_CALIB_SHIFT	4
+
+/**
+ * struct amlogic_thermal_soc_data
+ * @A, B, m, n: calibration parameters
+ * This structure is required for configuration of amlogic thermal driver.
+ */
+struct amlogic_thermal_soc_data {
+	int A;
+	int B;
+	int m;
+	int n;
+};
+
+/**
+ * struct amlogic_thermal_data
+ * @u_efuse_off: register offset to read fused calibration value
+ * @soc: calibration parameters structure pointer
+ * @regmap_config: regmap config for the device
+ * This structure is required for configuration of amlogic thermal driver.
+ */
+struct amlogic_thermal_data {
+	int id;
+	int u_efuse_off;
+	const struct amlogic_thermal_soc_data *soc;
+	const struct regmap_config *regmap_config;
+};
+
+struct amlogic_thermal {
+	struct platform_device *pdev;
+	const struct amlogic_thermal_data *data;
+	struct regmap *regmap;
+	struct regmap *sec_ao_map;
+	struct clk *clk;
+	struct thermal_zone_device *tzd;
+	u32 trim_info;
+	void __iomem *base;
+};
+
+/*
+ * Calculate a temperature value from a temperature code.
+ * The unit of the temperature is degree Celsius.
+ */
+static int code_to_temp(struct amlogic_thermal *pdata, int temp_code)
+{
+	const struct amlogic_thermal_soc_data *param = pdata->data->soc;
+	int temp;
+	s64 factor, Uptat, uefuse;
+
+	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->n * temp_code;
+	factor = div_s64(factor, 100);
+
+	Uptat = temp_code * param->m;
+	Uptat = div_s64(Uptat, 100);
+	Uptat = Uptat * BIT(16);
+	Uptat = div_s64(Uptat, BIT(16) + factor);
+
+	temp = (Uptat + uefuse) * param->A;
+	temp = div_s64(temp, BIT(16));
+	temp = (temp - param->B) * 100;
+
+	return temp;
+}
+
+static int amlogic_thermal_initialize(struct amlogic_thermal *pdata)
+{
+	int ret = 0;
+	int ver;
+
+	regmap_read(pdata->sec_ao_map, pdata->data->u_efuse_off,
+		    &pdata->trim_info);
+
+	ver = TSENSOR_TRIM_VERSION(pdata->trim_info);
+
+	if ((ver & TSENSOR_TRIM_CALIB_VALID_MASK) == 0) {
+		ret = -EINVAL;
+		dev_err(&pdata->pdev->dev,
+			"tsensor thermal calibration not supported: 0x%x!\n",
+			ver);
+	}
+
+	return ret;
+}
+
+static int amlogic_thermal_enable(struct amlogic_thermal *data)
+{
+	clk_prepare_enable(data->clk);
+	regmap_update_bits(data->regmap, TSENSOR_CFG_REG1,
+			   TSENSOR_CFG_REG1_ENABLE, TSENSOR_CFG_REG1_ENABLE);
+
+	return 0;
+}
+
+static int amlogic_thermal_disable(struct amlogic_thermal *data)
+{
+	regmap_update_bits(data->regmap, TSENSOR_CFG_REG1,
+			   TSENSOR_CFG_REG1_ENABLE, 0);
+	clk_disable(data->clk);
+
+	return 0;
+}
+
+static int amlogic_thermal_get_temp(void *data, int *temp)
+{
+	unsigned int tvalue;
+	struct amlogic_thermal *pdata = data;
+
+	if (!data)
+		return -EINVAL;
+
+	regmap_read(pdata->regmap, TSENSOR_STAT0, &tvalue);
+	*temp = code_to_temp(pdata,
+			     tvalue & TSENSOR_READ_TEMP_MASK);
+
+	return 0;
+}
+
+static const struct thermal_zone_of_device_ops amlogic_thermal_ops = {
+	.get_temp	= amlogic_thermal_get_temp,
+};
+
+static const struct regmap_config amlogic_thermal_regmap_config_g12 = {
+	.reg_bits = 8,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = TSENSOR_STAT9,
+};
+
+static const struct amlogic_thermal_soc_data amlogic_thermal_g12 = {
+	.A = 9411,
+	.B = 3159,
+	.m = 424,
+	.n = 324,
+};
+
+static const struct amlogic_thermal_data amlogic_thermal_g12_cpu_param = {
+	.id = 0,
+	.u_efuse_off = 0x128,
+	.soc = &amlogic_thermal_g12,
+	.regmap_config = &amlogic_thermal_regmap_config_g12,
+};
+
+static const struct amlogic_thermal_data amlogic_thermal_g12_ddr_param = {
+	.id = 1,
+	.u_efuse_off = 0xF0,
+	.soc = &amlogic_thermal_g12,
+	.regmap_config = &amlogic_thermal_regmap_config_g12,
+};
+
+static const struct of_device_id of_amlogic_thermal_match[] = {
+	{
+		.compatible = "amlogic,g12-ddr-thermal",
+		.data = &amlogic_thermal_g12_ddr_param,
+	},
+	{
+		.compatible = "amlogic,g12-cpu-thermal",
+		.data = &amlogic_thermal_g12_cpu_param,
+	},
+	{ /* end */ }
+};
+MODULE_DEVICE_TABLE(of, of_amlogic_thermal_match);
+
+static int amlogic_thermal_probe(struct platform_device *pdev)
+{
+	struct amlogic_thermal *pdata;
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+	int ret;
+
+	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata)
+		return -ENOMEM;
+
+	pdata->data = of_device_get_match_data(dev);
+	pdata->pdev = pdev;
+	platform_set_drvdata(pdev, pdata);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	pdata->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(pdata->base)) {
+		dev_err(dev, "failed to get io address\n");
+		return PTR_ERR(pdata->base);
+	}
+
+	pdata->regmap = devm_regmap_init_mmio(dev, pdata->base,
+					      pdata->data->regmap_config);
+	if (IS_ERR(pdata->regmap))
+		return PTR_ERR(pdata->regmap);
+
+	pdata->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(pdata->clk)) {
+		if (PTR_ERR(pdata->clk) != -EPROBE_DEFER)
+			dev_err(dev, "failed to get clock\n");
+		return PTR_ERR(pdata->clk);
+	}
+
+	pdata->sec_ao_map = syscon_regmap_lookup_by_phandle
+		(pdev->dev.of_node, "amlogic,ao-secure");
+	if (IS_ERR(pdata->sec_ao_map)) {
+		dev_err(dev, "syscon regmap lookup failed.\n");
+		return PTR_ERR(pdata->sec_ao_map);
+	}
+
+	pdata->tzd = devm_thermal_zone_of_sensor_register
+				(&pdev->dev,
+				 pdata->data->id,
+				 pdata,
+				 &amlogic_thermal_ops);
+	if (IS_ERR(pdata->tzd)) {
+		ret = PTR_ERR(pdata->tzd);
+		dev_err(dev, "Failed to register tsensor: %d\n", ret);
+		return PTR_ERR(pdata->tzd);
+	}
+
+	ret = amlogic_thermal_initialize(pdata);
+	if (ret)
+		return ret;
+
+	ret = amlogic_thermal_enable(pdata);
+	if (ret)
+		clk_unprepare(pdata->clk);
+
+	return ret;
+}
+
+static int amlogic_thermal_remove(struct platform_device *pdev)
+{
+	struct amlogic_thermal *data = platform_get_drvdata(pdev);
+
+	return amlogic_thermal_disable(data);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int amlogic_thermal_suspend(struct device *dev)
+{
+	struct amlogic_thermal *data = dev_get_drvdata(dev);
+
+	return amlogic_thermal_disable(data);
+}
+
+static int amlogic_thermal_resume(struct device *dev)
+{
+	struct amlogic_thermal *data = dev_get_drvdata(dev);
+
+	return amlogic_thermal_enable(data);
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(amlogic_thermal_pm_ops,
+			 amlogic_thermal_suspend, amlogic_thermal_resume);
+
+static struct platform_driver amlogic_thermal_driver = {
+	.driver = {
+		.name		= "amlogic_thermal",
+		.pm		= &amlogic_thermal_pm_ops,
+		.of_match_table = of_amlogic_thermal_match,
+	},
+	.probe	= amlogic_thermal_probe,
+	.remove	= amlogic_thermal_remove,
+};
+
+module_platform_driver(amlogic_thermal_driver);
+
+MODULE_AUTHOR("Guillaume La Roque <glaroque@baylibre.com>");
+MODULE_DESCRIPTION("Amlogic thermal driver");
+MODULE_LICENSE("GPL v2");
-- 
2.17.1