diff options
Diffstat (limited to 'target/linux/generic/patches-4.4/086-0003-thermal-bcm2835-add-thermal-driver-for-bcm2835-SoC.patch')
-rw-r--r-- | target/linux/generic/patches-4.4/086-0003-thermal-bcm2835-add-thermal-driver-for-bcm2835-SoC.patch | 365 |
1 files changed, 365 insertions, 0 deletions
diff --git a/target/linux/generic/patches-4.4/086-0003-thermal-bcm2835-add-thermal-driver-for-bcm2835-SoC.patch b/target/linux/generic/patches-4.4/086-0003-thermal-bcm2835-add-thermal-driver-for-bcm2835-SoC.patch new file mode 100644 index 0000000..d606804 --- /dev/null +++ b/target/linux/generic/patches-4.4/086-0003-thermal-bcm2835-add-thermal-driver-for-bcm2835-SoC.patch @@ -0,0 +1,365 @@ +From bcb7dd9ef206f7d646ed8dac6fe7772083714253 Mon Sep 17 00:00:00 2001 +From: Stefan Wahren <stefan.wahren@i2se.com> +Date: Fri, 31 Mar 2017 20:03:06 +0000 +Subject: [PATCH] thermal: bcm2835: add thermal driver for bcm2835 SoC +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +Add basic thermal driver for bcm2835 SoC. + +This driver currently make sure that tsense HW block is set up +correctly. + +Tested-by: Rafał Miłecki <rafal@milecki.pl> +Signed-off-by: Martin Sperl <kernel@martin.sperl.org> +Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> +Acked-by: Eric Anholt <eric@anholt.net> +Acked-by: Eduardo Valentin <edubezval@gmail.com> +Signed-off-by: Eduardo Valentin <edubezval@gmail.com> +--- + drivers/thermal/Kconfig | 8 + + drivers/thermal/Makefile | 1 + + drivers/thermal/bcm2835_thermal.c | 314 ++++++++++++++++++++++++++++++++++++++ + 3 files changed, 323 insertions(+) + create mode 100644 drivers/thermal/bcm2835_thermal.c + +--- a/drivers/thermal/Kconfig ++++ b/drivers/thermal/Kconfig +@@ -391,4 +391,12 @@ config QCOM_SPMI_TEMP_ALARM + real time die temperature if an ADC is present or an estimate of the + temperature based upon the over temperature stage value. + ++config BCM2835_THERMAL ++ tristate "Thermal sensors on bcm2835 SoC" ++ depends on ARCH_BCM2835 || COMPILE_TEST ++ depends on HAS_IOMEM ++ depends on THERMAL_OF ++ help ++ Support for thermal sensors on Broadcom bcm2835 SoCs. ++ + endif +--- a/drivers/thermal/Makefile ++++ b/drivers/thermal/Makefile +@@ -48,3 +48,4 @@ obj-$(CONFIG_INTEL_PCH_THERMAL) += intel + obj-$(CONFIG_ST_THERMAL) += st/ + obj-$(CONFIG_TEGRA_SOCTHERM) += tegra_soctherm.o + obj-$(CONFIG_HISI_THERMAL) += hisi_thermal.o ++obj-$(CONFIG_BCM2835_THERMAL) += bcm2835_thermal.o +--- /dev/null ++++ b/drivers/thermal/bcm2835_thermal.c +@@ -0,0 +1,314 @@ ++/* ++ * Driver for Broadcom BCM2835 SoC temperature sensor ++ * ++ * Copyright (C) 2016 Martin Sperl ++ * ++ * This program is free software; you can redistribute it and/or modify ++ * it under the terms of the GNU General Public License as published by ++ * the Free Software Foundation; either version 2 of the License, or ++ * (at your option) any later version. ++ * ++ * This program is distributed in the hope that it will be useful, ++ * but WITHOUT ANY WARRANTY; without even the implied warranty of ++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ++ * GNU General Public License for more details. ++ */ ++ ++#include <linux/clk.h> ++#include <linux/debugfs.h> ++#include <linux/device.h> ++#include <linux/err.h> ++#include <linux/io.h> ++#include <linux/kernel.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/thermal.h> ++ ++#define BCM2835_TS_TSENSCTL 0x00 ++#define BCM2835_TS_TSENSSTAT 0x04 ++ ++#define BCM2835_TS_TSENSCTL_PRWDW BIT(0) ++#define BCM2835_TS_TSENSCTL_RSTB BIT(1) ++ ++/* ++ * bandgap reference voltage in 6 mV increments ++ * 000b = 1178 mV, 001b = 1184 mV, ... 111b = 1220 mV ++ */ ++#define BCM2835_TS_TSENSCTL_CTRL_BITS 3 ++#define BCM2835_TS_TSENSCTL_CTRL_SHIFT 2 ++#define BCM2835_TS_TSENSCTL_CTRL_MASK \ ++ GENMASK(BCM2835_TS_TSENSCTL_CTRL_BITS + \ ++ BCM2835_TS_TSENSCTL_CTRL_SHIFT - 1, \ ++ BCM2835_TS_TSENSCTL_CTRL_SHIFT) ++#define BCM2835_TS_TSENSCTL_CTRL_DEFAULT 1 ++#define BCM2835_TS_TSENSCTL_EN_INT BIT(5) ++#define BCM2835_TS_TSENSCTL_DIRECT BIT(6) ++#define BCM2835_TS_TSENSCTL_CLR_INT BIT(7) ++#define BCM2835_TS_TSENSCTL_THOLD_SHIFT 8 ++#define BCM2835_TS_TSENSCTL_THOLD_BITS 10 ++#define BCM2835_TS_TSENSCTL_THOLD_MASK \ ++ GENMASK(BCM2835_TS_TSENSCTL_THOLD_BITS + \ ++ BCM2835_TS_TSENSCTL_THOLD_SHIFT - 1, \ ++ BCM2835_TS_TSENSCTL_THOLD_SHIFT) ++/* ++ * time how long the block to be asserted in reset ++ * which based on a clock counter (TSENS clock assumed) ++ */ ++#define BCM2835_TS_TSENSCTL_RSTDELAY_SHIFT 18 ++#define BCM2835_TS_TSENSCTL_RSTDELAY_BITS 8 ++#define BCM2835_TS_TSENSCTL_REGULEN BIT(26) ++ ++#define BCM2835_TS_TSENSSTAT_DATA_BITS 10 ++#define BCM2835_TS_TSENSSTAT_DATA_SHIFT 0 ++#define BCM2835_TS_TSENSSTAT_DATA_MASK \ ++ GENMASK(BCM2835_TS_TSENSSTAT_DATA_BITS + \ ++ BCM2835_TS_TSENSSTAT_DATA_SHIFT - 1, \ ++ BCM2835_TS_TSENSSTAT_DATA_SHIFT) ++#define BCM2835_TS_TSENSSTAT_VALID BIT(10) ++#define BCM2835_TS_TSENSSTAT_INTERRUPT BIT(11) ++ ++struct bcm2835_thermal_data { ++ struct thermal_zone_device *tz; ++ void __iomem *regs; ++ struct clk *clk; ++ struct dentry *debugfsdir; ++}; ++ ++static int bcm2835_thermal_adc2temp(u32 adc, int offset, int slope) ++{ ++ return offset + slope * adc; ++} ++ ++static int bcm2835_thermal_temp2adc(int temp, int offset, int slope) ++{ ++ temp -= offset; ++ temp /= slope; ++ ++ if (temp < 0) ++ temp = 0; ++ if (temp >= BIT(BCM2835_TS_TSENSSTAT_DATA_BITS)) ++ temp = BIT(BCM2835_TS_TSENSSTAT_DATA_BITS) - 1; ++ ++ return temp; ++} ++ ++static int bcm2835_thermal_get_temp(void *d, int *temp) ++{ ++ struct bcm2835_thermal_data *data = d; ++ u32 val = readl(data->regs + BCM2835_TS_TSENSSTAT); ++ ++ if (!(val & BCM2835_TS_TSENSSTAT_VALID)) ++ return -EIO; ++ ++ val &= BCM2835_TS_TSENSSTAT_DATA_MASK; ++ ++ *temp = bcm2835_thermal_adc2temp( ++ val, ++ thermal_zone_get_offset(data->tz), ++ thermal_zone_get_slope(data->tz)); ++ ++ return 0; ++} ++ ++static const struct debugfs_reg32 bcm2835_thermal_regs[] = { ++ { ++ .name = "ctl", ++ .offset = 0 ++ }, ++ { ++ .name = "stat", ++ .offset = 4 ++ } ++}; ++ ++static void bcm2835_thermal_debugfs(struct platform_device *pdev) ++{ ++ struct thermal_zone_device *tz = platform_get_drvdata(pdev); ++ struct bcm2835_thermal_data *data = tz->devdata; ++ struct debugfs_regset32 *regset; ++ ++ data->debugfsdir = debugfs_create_dir("bcm2835_thermal", NULL); ++ if (!data->debugfsdir) ++ return; ++ ++ regset = devm_kzalloc(&pdev->dev, sizeof(*regset), GFP_KERNEL); ++ if (!regset) ++ return; ++ ++ regset->regs = bcm2835_thermal_regs; ++ regset->nregs = ARRAY_SIZE(bcm2835_thermal_regs); ++ regset->base = data->regs; ++ ++ debugfs_create_regset32("regset", 0444, data->debugfsdir, regset); ++} ++ ++static struct thermal_zone_of_device_ops bcm2835_thermal_ops = { ++ .get_temp = bcm2835_thermal_get_temp, ++}; ++ ++/* ++ * Note: as per Raspberry Foundation FAQ ++ * (https://www.raspberrypi.org/help/faqs/#performanceOperatingTemperature) ++ * the recommended temperature range for the SoC -40C to +85C ++ * so the trip limit is set to 80C. ++ * this applies to all the BCM283X SoC ++ */ ++ ++static const struct of_device_id bcm2835_thermal_of_match_table[] = { ++ { ++ .compatible = "brcm,bcm2835-thermal", ++ }, ++ { ++ .compatible = "brcm,bcm2836-thermal", ++ }, ++ { ++ .compatible = "brcm,bcm2837-thermal", ++ }, ++ {}, ++}; ++MODULE_DEVICE_TABLE(of, bcm2835_thermal_of_match_table); ++ ++static int bcm2835_thermal_probe(struct platform_device *pdev) ++{ ++ const struct of_device_id *match; ++ struct thermal_zone_device *tz; ++ struct bcm2835_thermal_data *data; ++ struct resource *res; ++ int err = 0; ++ u32 val; ++ unsigned long rate; ++ ++ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); ++ if (!data) ++ return -ENOMEM; ++ ++ match = of_match_device(bcm2835_thermal_of_match_table, ++ &pdev->dev); ++ if (!match) ++ return -EINVAL; ++ ++ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); ++ data->regs = devm_ioremap_resource(&pdev->dev, res); ++ if (IS_ERR(data->regs)) { ++ err = PTR_ERR(data->regs); ++ dev_err(&pdev->dev, "Could not get registers: %d\n", err); ++ return err; ++ } ++ ++ data->clk = devm_clk_get(&pdev->dev, NULL); ++ if (IS_ERR(data->clk)) { ++ err = PTR_ERR(data->clk); ++ if (err != -EPROBE_DEFER) ++ dev_err(&pdev->dev, "Could not get clk: %d\n", err); ++ return err; ++ } ++ ++ err = clk_prepare_enable(data->clk); ++ if (err) ++ return err; ++ ++ rate = clk_get_rate(data->clk); ++ if ((rate < 1920000) || (rate > 5000000)) ++ dev_warn(&pdev->dev, ++ "Clock %pCn running at %pCr Hz is outside of the recommended range: 1.92 to 5MHz\n", ++ data->clk, data->clk); ++ ++ /* register of thermal sensor and get info from DT */ ++ tz = thermal_zone_of_sensor_register(&pdev->dev, 0, data, ++ &bcm2835_thermal_ops); ++ if (IS_ERR(tz)) { ++ err = PTR_ERR(tz); ++ dev_err(&pdev->dev, ++ "Failed to register the thermal device: %d\n", ++ err); ++ goto err_clk; ++ } ++ ++ /* ++ * right now the FW does set up the HW-block, so we are not ++ * touching the configuration registers. ++ * But if the HW is not enabled, then set it up ++ * using "sane" values used by the firmware right now. ++ */ ++ val = readl(data->regs + BCM2835_TS_TSENSCTL); ++ if (!(val & BCM2835_TS_TSENSCTL_RSTB)) { ++ int trip_temp, offset, slope; ++ ++ slope = thermal_zone_get_slope(tz); ++ offset = thermal_zone_get_offset(tz); ++ /* ++ * For now we deal only with critical, otherwise ++ * would need to iterate ++ */ ++ err = tz->ops->get_trip_temp(tz, 0, &trip_temp); ++ if (err < 0) { ++ err = PTR_ERR(tz); ++ dev_err(&pdev->dev, ++ "Not able to read trip_temp: %d\n", ++ err); ++ goto err_tz; ++ } ++ ++ /* set bandgap reference voltage and enable voltage regulator */ ++ val = (BCM2835_TS_TSENSCTL_CTRL_DEFAULT << ++ BCM2835_TS_TSENSCTL_CTRL_SHIFT) | ++ BCM2835_TS_TSENSCTL_REGULEN; ++ ++ /* use the recommended reset duration */ ++ val |= (0xFE << BCM2835_TS_TSENSCTL_RSTDELAY_SHIFT); ++ ++ /* trip_adc value from info */ ++ val |= bcm2835_thermal_temp2adc(trip_temp, ++ offset, ++ slope) ++ << BCM2835_TS_TSENSCTL_THOLD_SHIFT; ++ ++ /* write the value back to the register as 2 steps */ ++ writel(val, data->regs + BCM2835_TS_TSENSCTL); ++ val |= BCM2835_TS_TSENSCTL_RSTB; ++ writel(val, data->regs + BCM2835_TS_TSENSCTL); ++ } ++ ++ data->tz = tz; ++ ++ platform_set_drvdata(pdev, tz); ++ ++ bcm2835_thermal_debugfs(pdev); ++ ++ return 0; ++err_tz: ++ thermal_zone_of_sensor_unregister(&pdev->dev, tz); ++err_clk: ++ clk_disable_unprepare(data->clk); ++ ++ return err; ++} ++ ++static int bcm2835_thermal_remove(struct platform_device *pdev) ++{ ++ struct thermal_zone_device *tz = platform_get_drvdata(pdev); ++ struct bcm2835_thermal_data *data = tz->devdata; ++ ++ debugfs_remove_recursive(data->debugfsdir); ++ thermal_zone_of_sensor_unregister(&pdev->dev, tz); ++ clk_disable_unprepare(data->clk); ++ ++ return 0; ++} ++ ++static struct platform_driver bcm2835_thermal_driver = { ++ .probe = bcm2835_thermal_probe, ++ .remove = bcm2835_thermal_remove, ++ .driver = { ++ .name = "bcm2835_thermal", ++ .of_match_table = bcm2835_thermal_of_match_table, ++ }, ++}; ++module_platform_driver(bcm2835_thermal_driver); ++ ++MODULE_AUTHOR("Martin Sperl"); ++MODULE_DESCRIPTION("Thermal driver for bcm2835 chip"); ++MODULE_LICENSE("GPL"); |