From patchwork Fri Feb 21 05:38:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Evan Benn X-Patchwork-Id: 11395577 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 955821395 for ; Fri, 21 Feb 2020 05:38:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7487E24653 for ; Fri, 21 Feb 2020 05:38:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="NHBlsLvE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727145AbgBUFic (ORCPT ); Fri, 21 Feb 2020 00:38:32 -0500 Received: from mail-pj1-f66.google.com ([209.85.216.66]:39127 "EHLO mail-pj1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726994AbgBUFib (ORCPT ); Fri, 21 Feb 2020 00:38:31 -0500 Received: by mail-pj1-f66.google.com with SMTP id e9so235800pjr.4 for ; Thu, 20 Feb 2020 21:38:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=CapMNX7pjr8MkESV5PbFvA3nh0aG4lhz0SRP146DeOk=; b=NHBlsLvEzhPsV9lVrqrxLfj46dzf+dfvYfal/9H20MGjw4nLWWSVa8v81TGtfCiHGG UNImlkJ6xyOWAA6l1H1xA2JqGLXbVDYYjArPqkFMKmwUZffHJaGPMeXaVTJX8lG24W7Z 1BH97JwtFsJ//+S0hygIEpEECdThBP537UmUQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=CapMNX7pjr8MkESV5PbFvA3nh0aG4lhz0SRP146DeOk=; b=k/ANmarl3Ui3zLOaeZiWeesSpYzYafdbxse696oylijWQHx63YOIiG7wPb+80qEJ2b 1jwb6xVpjhEc0Ui3RS3Abhiqe/tpDmCGLbCfh5SJeHugNmhlTX5/i0Re+SSbGoA70uEX C5WxMD4tR5Yzwh2DIeFbWAzSDal+44B1KHXldiyhEN1WEX02g8jbXv9VgowoqUhsuHLh nxc+3a1ANX2EdttpO2zyE4EFPfe+lYC6TGB9ncr7fWbXJ+cyR3H5y6QDceMCe33ruZmS i6Z0KKKC+dlrAYqVq+x3f8WmrWW4u634qx0dnRN4LRm+yY+yvj3cWCMJLpqX0EpKQ26T AqSg== X-Gm-Message-State: APjAAAU95SfWBzXR/YgmBMP/yXQgxnGLiA84XDWZZHbIydUfkOAGbuaE dHtC4IqhKaKRS+m2g723EuXfLA== X-Google-Smtp-Source: APXvYqz+fNCi7RyQICRTNgU9IYDRlA2CBQL0xzTHdNzESzxk/Lp56MofgOU6MTmKnMrgVqSEjK8ojg== X-Received: by 2002:a17:90a:804a:: with SMTP id e10mr1046782pjw.41.1582263510005; Thu, 20 Feb 2020 21:38:30 -0800 (PST) Received: from localhost ([2401:fa00:9:14:1105:3e8a:838d:e326]) by smtp.gmail.com with ESMTPSA id m12sm1324157pfh.37.2020.02.20.21.38.25 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 20 Feb 2020 21:38:29 -0800 (PST) From: Evan Benn To: LKML Cc: jwerner@chromium.org, Evan Benn , "David S. Miller" , Greg Kroah-Hartman , Guenter Roeck , Jonathan Cameron , Mark Rutland , Matthias Brugger , Mauro Carvalho Chehab , Rob Herring , Wim Van Sebroeck , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-watchdog@vger.kernel.org Subject: [PATCH v2 1/2] dt-bindings: watchdog: Add mt8173,smc-wdt watchdog Date: Fri, 21 Feb 2020 16:38:01 +1100 Message-Id: <20200221163717.v2.1.I02ebc5b8743b1a71e0e15f68ea77e506d4e6f840@changeid> X-Mailer: git-send-email 2.25.0.265.gbab2e86ba0-goog In-Reply-To: <20200221053802.70716-1-evanbenn@chromium.org> References: <20200221053802.70716-1-evanbenn@chromium.org> MIME-Version: 1.0 Sender: linux-watchdog-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org This watchdog can be used on ARM systems with a Secure Monitor firmware to forward watchdog operations to firmware via a Secure Monitor Call. Signed-off-by: Evan Benn --- Changes in v2: - Change name arm > mt8173 .../bindings/watchdog/mt8173,smc-wdt.yaml | 30 +++++++++++++++++++ MAINTAINERS | 6 ++++ 2 files changed, 36 insertions(+) create mode 100644 Documentation/devicetree/bindings/watchdog/mt8173,smc-wdt.yaml diff --git a/Documentation/devicetree/bindings/watchdog/mt8173,smc-wdt.yaml b/Documentation/devicetree/bindings/watchdog/mt8173,smc-wdt.yaml new file mode 100644 index 0000000000000..ff45e13bc548b --- /dev/null +++ b/Documentation/devicetree/bindings/watchdog/mt8173,smc-wdt.yaml @@ -0,0 +1,30 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/watchdog/mt8173,smc-wdt.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: ARM Secure Monitor Call based watchdog + +allOf: + - $ref: "watchdog.yaml#" + +maintainers: + - Julius Werner + +properties: + compatible: + enum: + - mt8173,smc-wdt + +required: + - compatible + +examples: + - | + watchdog { + compatible = "mt8173,smc-wdt"; + timeout-sec = <15>; + }; + +... diff --git a/MAINTAINERS b/MAINTAINERS index e48ab79879ace..59e8779363c12 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1421,6 +1421,12 @@ S: Maintained F: Documentation/devicetree/bindings/interrupt-controller/amazon,al-fic.txt F: drivers/irqchip/irq-al-fic.c +ARM SMC WATCHDOG DRIVER +M: Julius Werner +R: Evan Benn +S: Maintained +F: devicetree/bindings/watchdog/mt8173,smc-wdt.yaml + ARM SMMU DRIVERS M: Will Deacon R: Robin Murphy From patchwork Fri Feb 21 05:38:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Evan Benn X-Patchwork-Id: 11395579 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8C19992A for ; Fri, 21 Feb 2020 05:38:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6179D222C4 for ; Fri, 21 Feb 2020 05:38:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="YW8gO+co" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727239AbgBUFim (ORCPT ); Fri, 21 Feb 2020 00:38:42 -0500 Received: from mail-pj1-f68.google.com ([209.85.216.68]:39136 "EHLO mail-pj1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726088AbgBUFil (ORCPT ); Fri, 21 Feb 2020 00:38:41 -0500 Received: by mail-pj1-f68.google.com with SMTP id e9so235979pjr.4 for ; Thu, 20 Feb 2020 21:38:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=Ihebwe3wpv8TVI2Q+rKN93pQGL38v53adMqGT/gjBKI=; b=YW8gO+coOvx+JcdbsuG4ZcZbjmeoHxzIhZjg0NFDBPa0xyzI7n60/g46BdJPdqNeq+ lEAdpfrthUVphl8fO/+pgXgelLyg3lIQVgwFrzruzjYJ5w5+jQYKSGLoneqo7GA8PgRf JDaxKJ5DI5xUMB64saHppf7Q1Q51iMc0AkRkQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=Ihebwe3wpv8TVI2Q+rKN93pQGL38v53adMqGT/gjBKI=; b=FjeEs6iDmLqQ2Wz65pgQF0qERuCoRANRMwEHpBGIEm/lIPaEYJ3jfjGPqS0IgbYpla 12xlF9pUInZisf6JUvb/jdasQ+jmal1Sy4sDPWABr0VHsyp0GNFXmpLeHcBMZD8D40EY /TsNkzqN54ekcOfDSrA9GcXuXEzhR42fDxEA38wgo6CQP3Y+tRoMNkroQtLvCt2RY+Df UdBV9FMeXYw+PuecgHRmlgF0o55khH211LtICJGgnFrtnrC2A77d7OGMFDp1eH8RGxZP Wb0ghceIXA9kBNf6UAIoGe3Q50uh+JVfWcjW/36dG17JXP0dL8F93Wiy8jvxY0RId3n5 L32g== X-Gm-Message-State: APjAAAUPZf5IH6JEKuyKiqyHT/6YAHp3SUyZZ56uCbyRmPfsmsokfc5K 5826sIhQynGJUFEK5CpdXmSfrQ== X-Google-Smtp-Source: APXvYqx/6KGlYHS4T9Zfe8IxLNfGJ8OG+MYBFpk7RP/CnmSAeGWAOxlIc75L68Uthhnb4jRkuJNbng== X-Received: by 2002:a17:90a:26ab:: with SMTP id m40mr1097883pje.42.1582263520883; Thu, 20 Feb 2020 21:38:40 -0800 (PST) Received: from localhost ([2401:fa00:9:14:1105:3e8a:838d:e326]) by smtp.gmail.com with ESMTPSA id y197sm1373877pfc.79.2020.02.20.21.38.34 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 20 Feb 2020 21:38:40 -0800 (PST) From: Evan Benn To: LKML Cc: jwerner@chromium.org, Evan Benn , Anson Huang , Catalin Marinas , =?utf-8?b?Q2zDqW1lbnQgUMOpcm9u?= , "David S. Miller" , Dinh Nguyen , Greg Kroah-Hartman , Guenter Roeck , Jonathan Cameron , Leonard Crestez , Marcin Juszkiewicz , Matthias Brugger , Mauro Carvalho Chehab , Olof Johansson , Rob Herring , Shawn Guo , Will Deacon , Wim Van Sebroeck , linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-watchdog@vger.kernel.org Subject: [PATCH v2 2/2] watchdog: Add new mt8173_smc_wdt watchdog driver Date: Fri, 21 Feb 2020 16:38:02 +1100 Message-Id: <20200221163717.v2.2.I7c8247c29891a538f258cb47828d58acf22c95a2@changeid> X-Mailer: git-send-email 2.25.0.265.gbab2e86ba0-goog In-Reply-To: <20200221053802.70716-1-evanbenn@chromium.org> References: <20200221053802.70716-1-evanbenn@chromium.org> MIME-Version: 1.0 Sender: linux-watchdog-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org From: Julius Werner This patch adds a watchdog driver that can be used on ARM systems with the appropriate watchdog implemented in Secure Monitor firmware. The driver communicates with firmware via a Secure Monitor Call. This may be useful for platforms using TrustZone that want the Secure Monitor firmware to have the final control over the watchdog. This is implemented on mt8173 chromebook devices oak, elm and hana in arm trusted firmware file plat/mediatek/mt8173/drivers/wdt/wdt.c. Signed-off-by: Julius Werner Signed-off-by: Evan Benn --- Changes in v2: - use watchdog_stop_on_reboot - use watchdog_stop_on_unregister - use devm_watchdog_register_device - remove smcwd_shutdown, smcwd_remove - change error codes MAINTAINERS | 1 + arch/arm64/configs/defconfig | 1 + drivers/watchdog/Kconfig | 13 +++ drivers/watchdog/Makefile | 1 + drivers/watchdog/mt8173_smc_wdt.c | 160 ++++++++++++++++++++++++++++++ 5 files changed, 176 insertions(+) create mode 100644 drivers/watchdog/mt8173_smc_wdt.c diff --git a/MAINTAINERS b/MAINTAINERS index 59e8779363c12..94e295e16e128 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1426,6 +1426,7 @@ M: Julius Werner R: Evan Benn S: Maintained F: devicetree/bindings/watchdog/mt8173,smc-wdt.yaml +F: drivers/watchdog/mt8173_smc_wdt.c ARM SMMU DRIVERS M: Will Deacon diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig index b2f667307f829..11d94c9258b79 100644 --- a/arch/arm64/configs/defconfig +++ b/arch/arm64/configs/defconfig @@ -451,6 +451,7 @@ CONFIG_QCOM_TSENS=y CONFIG_UNIPHIER_THERMAL=y CONFIG_WATCHDOG=y CONFIG_ARM_SP805_WATCHDOG=y +CONFIG_MT8173_SMC_WATCHDOG=y CONFIG_S3C2410_WATCHDOG=y CONFIG_DW_WATCHDOG=y CONFIG_SUNXI_WATCHDOG=m diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index cec868f8db3f9..b4e55db7a4dcf 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -857,6 +857,19 @@ config DIGICOLOR_WATCHDOG To compile this driver as a module, choose M here: the module will be called digicolor_wdt. +config MT8173_SMC_WATCHDOG + tristate "ARM Secure Monitor Call based watchdog support" + depends on ARM || ARM64 + depends on OF + depends on HAVE_ARM_SMCCC + select WATCHDOG_CORE + help + Say Y here to include support for a watchdog timer + implemented by the EL3 Secure Monitor on ARM platforms. + Requires firmware support. + To compile this driver as a module, choose M here: the + module will be called arm_smc_wdt. + config LPC18XX_WATCHDOG tristate "LPC18xx/43xx Watchdog" depends on ARCH_LPC18XX || COMPILE_TEST diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 2ee352bf3372d..d1381234892ef 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -92,6 +92,7 @@ obj-$(CONFIG_STM32_WATCHDOG) += stm32_iwdg.o obj-$(CONFIG_UNIPHIER_WATCHDOG) += uniphier_wdt.o obj-$(CONFIG_RTD119X_WATCHDOG) += rtd119x_wdt.o obj-$(CONFIG_SPRD_WATCHDOG) += sprd_wdt.o +obj-$(CONFIG_MT8173_SMC_WATCHDOG) += mt8173_smc_wdt.o obj-$(CONFIG_PM8916_WATCHDOG) += pm8916_wdt.o # X86 (i386 + ia64 + x86_64) Architecture diff --git a/drivers/watchdog/mt8173_smc_wdt.c b/drivers/watchdog/mt8173_smc_wdt.c new file mode 100644 index 0000000000000..681aa42c7d277 --- /dev/null +++ b/drivers/watchdog/mt8173_smc_wdt.c @@ -0,0 +1,160 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ARM Secure Monitor Call watchdog driver + * + * Copyright 2020 Google LLC. + * Julius Werner + * Based on mtk_wdt.c + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define DRV_NAME "mt8173_smc_wdt" +#define DRV_VERSION "1.0" + +#define SMCWD_FUNC_ID 0x82003d06 + +enum smcwd_call { + SMCWD_INFO = 0, + SMCWD_SET_TIMEOUT = 1, + SMCWD_ENABLE = 2, + SMCWD_PET = 3, +}; + +static bool nowayout = WATCHDOG_NOWAYOUT; +static unsigned int timeout; + +static int smcwd_call(enum smcwd_call call, unsigned long arg, + struct arm_smccc_res *res) +{ + struct arm_smccc_res local_res; + + if (!res) + res = &local_res; + + arm_smccc_smc(SMCWD_FUNC_ID, call, arg, 0, 0, 0, 0, 0, res); + + if (res->a0 == PSCI_RET_NOT_SUPPORTED) + return -ENODEV; + if (res->a0 == PSCI_RET_INVALID_PARAMS) + return -EINVAL; + if (res->a0 != PSCI_RET_SUCCESS) + return -EIO; + return 0; +} + +static int smcwd_ping(struct watchdog_device *wdd) +{ + return smcwd_call(SMCWD_PET, 0, NULL); +} + +static int smcwd_set_timeout(struct watchdog_device *wdd, unsigned int timeout) +{ + int res; + + res = smcwd_call(SMCWD_SET_TIMEOUT, timeout, NULL); + if (!res) + wdd->timeout = timeout; + return res; +} + +static int smcwd_stop(struct watchdog_device *wdd) +{ + return smcwd_call(SMCWD_ENABLE, 0, NULL); +} + +static int smcwd_start(struct watchdog_device *wdd) +{ + return smcwd_call(SMCWD_ENABLE, 1, NULL); +} + +static const struct watchdog_info smcwd_info = { + .identity = DRV_NAME, + .options = WDIOF_SETTIMEOUT | + WDIOF_KEEPALIVEPING | + WDIOF_MAGICCLOSE, +}; + +static const struct watchdog_ops smcwd_ops = { + .start = smcwd_start, + .stop = smcwd_stop, + .ping = smcwd_ping, + .set_timeout = smcwd_set_timeout, +}; + +static int smcwd_probe(struct platform_device *pdev) +{ + struct watchdog_device *wdd; + int err; + struct arm_smccc_res res; + + err = smcwd_call(SMCWD_INFO, 0, &res); + if (err < 0) + return err; + + wdd = devm_kzalloc(&pdev->dev, sizeof(*wdd), GFP_KERNEL); + if (!wdd) + return -ENOMEM; + + platform_set_drvdata(pdev, wdd); + + wdd->info = &smcwd_info; + wdd->ops = &smcwd_ops; + wdd->timeout = res.a2; + wdd->max_timeout = res.a2; + wdd->min_timeout = res.a1; + wdd->parent = &pdev->dev; + + watchdog_stop_on_reboot(wdd); + watchdog_stop_on_unregister(wdd); + watchdog_set_nowayout(wdd, nowayout); + watchdog_init_timeout(wdd, timeout, &pdev->dev); + err = smcwd_set_timeout(wdd, wdd->timeout); + if (err) + return err; + + err = devm_watchdog_register_device(&pdev->dev, wdd); + if (err) + return err; + + dev_info(&pdev->dev, "Watchdog registered (timeout=%d sec, nowayout=%d)\n", + wdd->timeout, nowayout); + + return 0; +} + +static const struct of_device_id smcwd_dt_ids[] = { + { .compatible = "mt8173,smc-wdt" }, + {} +}; +MODULE_DEVICE_TABLE(of, smcwd_dt_ids); + +static struct platform_driver smcwd_driver = { + .probe = smcwd_probe, + .driver = { + .name = DRV_NAME, + .of_match_table = smcwd_dt_ids, + }, +}; + +module_platform_driver(smcwd_driver); + +module_param(timeout, uint, 0); +MODULE_PARM_DESC(timeout, "Watchdog heartbeat in seconds"); + +module_param(nowayout, bool, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Julius Werner "); +MODULE_DESCRIPTION("ARM Secure Monitor Call Watchdog Driver"); +MODULE_VERSION(DRV_VERSION);