From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752764AbeEVUzF (ORCPT ); Tue, 22 May 2018 16:55:05 -0400 Received: from bh-25.webhostbox.net ([208.91.199.152]:52103 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752986AbeEVUzA (ORCPT ); Tue, 22 May 2018 16:55:00 -0400 Date: Tue, 22 May 2018 13:54:57 -0700 From: Guenter Roeck To: Ray Jui Cc: Wim Van Sebroeck , Rob Herring , Mark Rutland , Frank Rowand , Catalin Marinas , Will Deacon , linux-watchdog@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, bcm-kernel-feedback-list@broadcom.com Subject: Re: [PATCH 3/5] watchdog: sp805: set WDOG_HW_RUNNING when appropriate Message-ID: <20180522205457.GA16363@roeck-us.net> References: <1527014840-21236-1-git-send-email-ray.jui@broadcom.com> <1527014840-21236-4-git-send-email-ray.jui@broadcom.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1527014840-21236-4-git-send-email-ray.jui@broadcom.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Authenticated_sender: guenter@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: guenter@roeck-us.net X-Authenticated-Sender: bh-25.webhostbox.net: guenter@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 22, 2018 at 11:47:18AM -0700, Ray Jui wrote: > If the watchdog hardware is already enabled during the boot process, > when the Linux watchdog driver loads, it should reset the watchdog and > tell the watchdog framework. As a result, ping can be generated from > the watchdog framework, until the userspace watchdog daemon takes over > control > > Signed-off-by: Ray Jui > Reviewed-by: Vladimir Olovyannikov > Reviewed-by: Scott Branden > --- > drivers/watchdog/sp805_wdt.c | 22 ++++++++++++++++++++++ > 1 file changed, 22 insertions(+) > > diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c > index 1484609..408ffbe 100644 > --- a/drivers/watchdog/sp805_wdt.c > +++ b/drivers/watchdog/sp805_wdt.c > @@ -42,6 +42,7 @@ > /* control register masks */ > #define INT_ENABLE (1 << 0) > #define RESET_ENABLE (1 << 1) > + #define ENABLE_MASK (INT_ENABLE | RESET_ENABLE) > #define WDTINTCLR 0x00C > #define WDTRIS 0x010 > #define WDTMIS 0x014 > @@ -74,6 +75,18 @@ module_param(nowayout, bool, 0); > MODULE_PARM_DESC(nowayout, > "Set to 1 to keep watchdog running after device release"); > > +/* returns true if wdt is running; otherwise returns false */ > +static bool wdt_is_running(struct watchdog_device *wdd) > +{ > + struct sp805_wdt *wdt = watchdog_get_drvdata(wdd); > + > + if ((readl_relaxed(wdt->base + WDTCONTROL) & ENABLE_MASK) == > + ENABLE_MASK) > + return true; > + else > + return false; return !!(readl_relaxed(wdt->base + WDTCONTROL) & ENABLE_MASK)); > +} > + > /* This routine finds load value that will reset system in required timout */ > static int wdt_setload(struct watchdog_device *wdd, unsigned int timeout) > { > @@ -239,6 +252,15 @@ sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id) > watchdog_init_timeout(&wdt->wdd, 0, &adev->dev); > wdt_setload(&wdt->wdd, wdt->wdd.timeout); > > + /* > + * If HW is already running, enable/reset the wdt and set the running > + * bit to tell the wdt subsystem > + */ > + if (wdt_is_running(&wdt->wdd)) { > + wdt_enable(&wdt->wdd); > + set_bit(WDOG_HW_RUNNING, &wdt->wdd.status); > + } > + > ret = watchdog_register_device(&wdt->wdd); > if (ret) { > dev_err(&adev->dev, "watchdog_register_device() failed: %d\n", > -- > 2.1.4 > From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@roeck-us.net (Guenter Roeck) Date: Tue, 22 May 2018 13:54:57 -0700 Subject: [PATCH 3/5] watchdog: sp805: set WDOG_HW_RUNNING when appropriate In-Reply-To: <1527014840-21236-4-git-send-email-ray.jui@broadcom.com> References: <1527014840-21236-1-git-send-email-ray.jui@broadcom.com> <1527014840-21236-4-git-send-email-ray.jui@broadcom.com> Message-ID: <20180522205457.GA16363@roeck-us.net> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, May 22, 2018 at 11:47:18AM -0700, Ray Jui wrote: > If the watchdog hardware is already enabled during the boot process, > when the Linux watchdog driver loads, it should reset the watchdog and > tell the watchdog framework. As a result, ping can be generated from > the watchdog framework, until the userspace watchdog daemon takes over > control > > Signed-off-by: Ray Jui > Reviewed-by: Vladimir Olovyannikov > Reviewed-by: Scott Branden > --- > drivers/watchdog/sp805_wdt.c | 22 ++++++++++++++++++++++ > 1 file changed, 22 insertions(+) > > diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c > index 1484609..408ffbe 100644 > --- a/drivers/watchdog/sp805_wdt.c > +++ b/drivers/watchdog/sp805_wdt.c > @@ -42,6 +42,7 @@ > /* control register masks */ > #define INT_ENABLE (1 << 0) > #define RESET_ENABLE (1 << 1) > + #define ENABLE_MASK (INT_ENABLE | RESET_ENABLE) > #define WDTINTCLR 0x00C > #define WDTRIS 0x010 > #define WDTMIS 0x014 > @@ -74,6 +75,18 @@ module_param(nowayout, bool, 0); > MODULE_PARM_DESC(nowayout, > "Set to 1 to keep watchdog running after device release"); > > +/* returns true if wdt is running; otherwise returns false */ > +static bool wdt_is_running(struct watchdog_device *wdd) > +{ > + struct sp805_wdt *wdt = watchdog_get_drvdata(wdd); > + > + if ((readl_relaxed(wdt->base + WDTCONTROL) & ENABLE_MASK) == > + ENABLE_MASK) > + return true; > + else > + return false; return !!(readl_relaxed(wdt->base + WDTCONTROL) & ENABLE_MASK)); > +} > + > /* This routine finds load value that will reset system in required timout */ > static int wdt_setload(struct watchdog_device *wdd, unsigned int timeout) > { > @@ -239,6 +252,15 @@ sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id) > watchdog_init_timeout(&wdt->wdd, 0, &adev->dev); > wdt_setload(&wdt->wdd, wdt->wdd.timeout); > > + /* > + * If HW is already running, enable/reset the wdt and set the running > + * bit to tell the wdt subsystem > + */ > + if (wdt_is_running(&wdt->wdd)) { > + wdt_enable(&wdt->wdd); > + set_bit(WDOG_HW_RUNNING, &wdt->wdd.status); > + } > + > ret = watchdog_register_device(&wdt->wdd); > if (ret) { > dev_err(&adev->dev, "watchdog_register_device() failed: %d\n", > -- > 2.1.4 >