From patchwork Sun Mar 12 22:11:05 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Wahren X-Patchwork-Id: 9619579 X-Patchwork-Delegate: eduardo.valentin@ti.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 63AF460414 for ; Sun, 12 Mar 2017 22:11:47 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 55D8528343 for ; Sun, 12 Mar 2017 22:11:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4C0D128346; Sun, 12 Mar 2017 22:11:47 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.4 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RCVD_IN_SORBS_SPAM autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 608CF2840B for ; Sun, 12 Mar 2017 22:11:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935414AbdCLWLq (ORCPT ); Sun, 12 Mar 2017 18:11:46 -0400 Received: from mout.kundenserver.de ([212.227.126.133]:62950 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935371AbdCLWLi (ORCPT ); Sun, 12 Mar 2017 18:11:38 -0400 Received: from localhost.localdomain ([95.91.4.8]) by mrelayeu.kundenserver.de (mreue004 [212.227.15.167]) with ESMTPSA (Nemesis) id 0LeQ93-1cRvnD0pnJ-00qBWj; Sun, 12 Mar 2017 23:11:22 +0100 From: Stefan Wahren To: Eduardo Valentin , Zhang Rui , kernel@martin.sperl.org Cc: Eric Anholt , Rob Herring , Frank Rowand , Florian Fainelli , linux-rpi-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-pm@vger.kernel.org, Stefan Wahren Subject: [PATCH V11 6/6] thermal: bcm2835: add thermal driver for bcm2835 SoC Date: Sun, 12 Mar 2017 22:11:05 +0000 Message-Id: <1489356665-3175-7-git-send-email-stefan.wahren@i2se.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1489356665-3175-1-git-send-email-stefan.wahren@i2se.com> References: <1489356665-3175-1-git-send-email-stefan.wahren@i2se.com> X-Provags-ID: V03:K0:9EuoKSM1Tfy1yGcxnqC4DuKt/dkqQA+6PPTKMCVUnSMpu18jgtO 7yHrng4xHviB2Y7wMxZ/nnAlss+q8ltwXrCVLi9/p/x8NCdCDhnhq7gigN2ZrOEcnjjFvBG Kp9fnJWmHYZDIOn2mBxuRLzRDXRirSlU0a7v6YlMWnphd+2vKInHjYFOHx78fliVbG92vcQ AKtCfvqZikSDuGKRDyxEw== X-UI-Out-Filterresults: notjunk:1; V01:K0:fp0UOh6kZig=:FYRmegXQ31yHME8M/Zlz5V xM0Bf41H/X2HZp3JEJK0vwdvOIfnipE1h0LXoLB9Ru8c2sabbOIJ9sF+OjMyDrnTsMo8QEUf5 ygV0zRxDOv7x2VLwpe5bBc6TPDIH6nVBqnDDL9wIi4J8LIdVKMl8WaFsES6bOilbW+b1AScJL oR0tIl8tpwc/9/H1bUUUpJK3JVanDe0e44bFWEy94M0y5NCIlT06iV7EzyzB5GCWivT0MliEm e7Is0dRhJvHXt6HVLjYNXDAe1o8z0W9hfq5ct6kyTugpEn1ncGQeBuAxJn4Pa6B1yyhxJD7LD EhPxwBSHuJGBSmuBzEJzoNJbcLtc/nyF3qSxWZPeav8tRgevYMtJa57tET/qUVO4iw5Prkkou okkwT4WDDBSelzT8InJbMgWqFsW1ZbZgbWWZvG1zgITUjmUinnWUW/JFKK44n3C1SlSzN2vsK RTRXLHmwgv1/uXD3K0seH+uloT2g/aLeniq1+j5LQiHTl+KuyWApwLR5pHBmXL0Ond+46bWZ+ klG4P7CO6NAwr/r8DCjBS2NQXBk2mzhaHJFo9kwdXVeYfbd2GKS9hro4+iuBJANt1Dv+rM07i vMhXthG6UnuGxAOhNa5piYfXob3Qe4M1hNZNmewlGRrihr48dvNEe4xZvm9WjP5dj7EKdUzkG OPxDf/kAutb/youohNiJ4iuCsr7FTi7xbKv6ob1dABqEbPm6TygAQDz/hIcdJ/X4aihc= Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add basic thermal driver for bcm2835 SoC. This driver currently make sure that tsense HW block is set up correctly. Signed-off-by: Martin Sperl Signed-off-by: Stefan Wahren Acked-by: Eric Anholt Acked-by: Eduardo Valentin --- drivers/thermal/Kconfig | 8 + drivers/thermal/Makefile | 1 + drivers/thermal/bcm2835_thermal.c | 315 +++++++++++++++++++++++++++++++++++++ 3 files changed, 324 insertions(+) create mode 100644 drivers/thermal/bcm2835_thermal.c diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index 776b343..3bd2406 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -453,4 +453,12 @@ config ZX2967_THERMAL the primitive temperature sensor embedded in zx2967 SoCs. This sensor generates the real time die temperature. +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 diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index 7adae20..f23cde0 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -58,3 +58,4 @@ 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_ZX2967_THERMAL) += zx2967_thermal.o +obj-$(CONFIG_BCM2835_THERMAL) += bcm2835_thermal.o diff --git a/drivers/thermal/bcm2835_thermal.c b/drivers/thermal/bcm2835_thermal.c new file mode 100644 index 0000000..a9768f1 --- /dev/null +++ b/drivers/thermal/bcm2835_thermal.c @@ -0,0 +1,315 @@ +/* + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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, +}; + +static const struct of_device_id 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; +} + +/* + * 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 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");