mirror of https://github.com/hak5/openwrt-owl.git
366 lines
10 KiB
Diff
366 lines
10 KiB
Diff
|
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
|
||
|
@@ -434,4 +434,12 @@ depends on (ARCH_QCOM && OF) || COMPILE_
|
||
|
source "drivers/thermal/qcom/Kconfig"
|
||
|
endmenu
|
||
|
|
||
|
+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
|
||
|
@@ -55,3 +55,4 @@ obj-$(CONFIG_TEGRA_SOCTHERM) += tegra/
|
||
|
obj-$(CONFIG_HISI_THERMAL) += hisi_thermal.o
|
||
|
obj-$(CONFIG_MTK_THERMAL) += mtk_thermal.o
|
||
|
obj-$(CONFIG_GENERIC_ADC_THERMAL) += thermal-generic-adc.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");
|