From patchwork Mon Aug 24 17:01:19 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fu Wei Fu X-Patchwork-Id: 52640 Return-Path: X-Original-To: linaro@patches.linaro.org Delivered-To: linaro@patches.linaro.org Received: from mail-la0-f72.google.com (mail-la0-f72.google.com [209.85.215.72]) by patches.linaro.org (Postfix) with ESMTPS id C04C022DD4 for ; Mon, 24 Aug 2015 17:03:10 +0000 (UTC) Received: by labia3 with SMTP id ia3sf18073534lab.3 for ; Mon, 24 Aug 2015 10:03:09 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:delivered-to:from:to:cc:subject :date:message-id:in-reply-to:references:sender:precedence:list-id :x-original-sender:x-original-authentication-results:mailing-list :list-post:list-help:list-archive:list-unsubscribe; bh=tEtvOcuuhz5JalywTPGOIENvh6VmNycNVxCMq7g7CsU=; b=VS1F1++jsguhMvNGYPBwJN5nMAhbEenp8QGRMXUDD4Mx779Sq1zPwNVFKC22Fj6eBY JXhLdcOrMkrAAJeUB850Qkhgbe36T3UMGUn1YKQ3uT7H/AvxG+gRfRXyEZ0OoinRsGpe 2anHsOjW6cCna/441dyeSZbqfnqg/LW+2nh87SOwAwH3l3XG4ohesSqp6DlSdARjDDOG cbyMAQdI+2cJFyN8uDCMowAyNMrSaV2DoX36nWBYJl8r5+SgKmlJpZ6xT+lOZXqI/diV RwVd55yXYURd/eV7GfrLPBcZgw5JUjJ3w/OxbC1E8rZu4t8BD3eLyzV7V5npNScSrS/N fNXg== X-Gm-Message-State: ALoCoQkm26C8KoiRK5sMIPpl6Zgz5DpXpoKqUvP9DRClfW0B+B64frJAzRmmOdwlhSd3+UDfsexG X-Received: by 10.194.184.6 with SMTP id eq6mr7078698wjc.4.1440435789746; Mon, 24 Aug 2015 10:03:09 -0700 (PDT) MIME-Version: 1.0 X-BeenThere: patchwork-forward@linaro.org Received: by 10.152.6.101 with SMTP id z5ls553101laz.65.gmail; Mon, 24 Aug 2015 10:03:09 -0700 (PDT) X-Received: by 10.152.27.38 with SMTP id q6mr18900355lag.24.1440435789546; Mon, 24 Aug 2015 10:03:09 -0700 (PDT) Received: from mail-la0-f50.google.com (mail-la0-f50.google.com. [209.85.215.50]) by mx.google.com with ESMTPS id py9si13646696lbb.165.2015.08.24.10.03.09 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 24 Aug 2015 10:03:09 -0700 (PDT) Received-SPF: pass (google.com: domain of patch+caf_=patchwork-forward=linaro.org@linaro.org designates 209.85.215.50 as permitted sender) client-ip=209.85.215.50; Received: by lalv9 with SMTP id v9so81650148lal.0 for ; Mon, 24 Aug 2015 10:03:09 -0700 (PDT) X-Received: by 10.152.22.133 with SMTP id d5mr21012031laf.112.1440435789425; Mon, 24 Aug 2015 10:03:09 -0700 (PDT) X-Forwarded-To: patchwork-forward@linaro.org X-Forwarded-For: patch@linaro.org patchwork-forward@linaro.org Delivered-To: patch@linaro.org Received: by 10.112.162.200 with SMTP id yc8csp2609400lbb; Mon, 24 Aug 2015 10:03:07 -0700 (PDT) X-Received: by 10.70.11.101 with SMTP id p5mr47325649pdb.103.1440435787017; Mon, 24 Aug 2015 10:03:07 -0700 (PDT) Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id p10si28368065pds.132.2015.08.24.10.03.06; Mon, 24 Aug 2015 10:03:07 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754891AbbHXRDA (ORCPT + 28 others); Mon, 24 Aug 2015 13:03:00 -0400 Received: from mail-pd0-f170.google.com ([209.85.192.170]:33086 "EHLO mail-pd0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932658AbbHXRC4 (ORCPT ); Mon, 24 Aug 2015 13:02:56 -0400 Received: by pdrh1 with SMTP id h1so56534973pdr.0 for ; Mon, 24 Aug 2015 10:02:56 -0700 (PDT) X-Received: by 10.70.36.138 with SMTP id q10mr47123706pdj.32.1440435776040; Mon, 24 Aug 2015 10:02:56 -0700 (PDT) Received: from localhost.localdomain (li400-65.members.linode.com. [106.187.50.65]) by smtp.googlemail.com with ESMTPSA id fu4sm17997515pbb.59.2015.08.24.10.02.47 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 24 Aug 2015 10:02:55 -0700 (PDT) From: fu.wei@linaro.org To: Suravee.Suthikulpanit@amd.com, hanjun.guo@linaro.org, linaro-acpi@lists.linaro.org, linux-watchdog@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org Cc: tekkamanninja@gmail.com, graeme.gregory@linaro.org, al.stone@linaro.org, arnd@arndb.de, linux@roeck-us.net, vgandhi@codeaurora.org, wim@iguana.be, jcm@redhat.com, leo.duran@amd.com, corbet@lwn.net, mark.rutland@arm.com, catalin.marinas@arm.com, will.deacon@arm.com, rjw@rjwysocki.net, dyoung@redhat.com, panand@redhat.com, Fu Wei Subject: [PATCH v7 4/8] Watchdog: introdouce "pretimeout" into framework Date: Tue, 25 Aug 2015 01:01:19 +0800 Message-Id: <1440435683-7343-5-git-send-email-fu.wei@linaro.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1440435683-7343-1-git-send-email-fu.wei@linaro.org> References: <=fu.wei@linaro.org> <1440435683-7343-1-git-send-email-fu.wei@linaro.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: list List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Removed-Original-Auth: Dkim didn't pass. X-Original-Sender: fu.wei@linaro.org X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of patch+caf_=patchwork-forward=linaro.org@linaro.org designates 209.85.215.50 as permitted sender) smtp.mailfrom=patch+caf_=patchwork-forward=linaro.org@linaro.org Mailing-list: list patchwork-forward@linaro.org; contact patchwork-forward+owners@linaro.org X-Google-Group-Id: 836684582541 List-Post: , List-Help: , List-Archive: List-Unsubscribe: , From: Fu Wei Also update Documentation/watchdog/watchdog-kernel-api.txt to introduce: (1)the new elements in the watchdog_device and watchdog_ops struct; (2)the new API "watchdog_init_timeouts" Reasons: (1)kernel already has two watchdog drivers are using "pretimeout": drivers/char/ipmi/ipmi_watchdog.c drivers/watchdog/kempld_wdt.c(but the definition is different) (2)some other drivers are going to use this: ARM SBSA Generic Watchdog Signed-off-by: Fu Wei --- Documentation/watchdog/watchdog-kernel-api.txt | 47 ++++++++++-- drivers/watchdog/watchdog_core.c | 98 ++++++++++++++++++-------- drivers/watchdog/watchdog_dev.c | 53 ++++++++++++++ include/linux/watchdog.h | 39 ++++++++-- 4 files changed, 200 insertions(+), 37 deletions(-) diff --git a/Documentation/watchdog/watchdog-kernel-api.txt b/Documentation/watchdog/watchdog-kernel-api.txt index d8b0d33..1fadeb9 100644 --- a/Documentation/watchdog/watchdog-kernel-api.txt +++ b/Documentation/watchdog/watchdog-kernel-api.txt @@ -53,6 +53,9 @@ struct watchdog_device { unsigned int timeout; unsigned int min_timeout; unsigned int max_timeout; + unsigned int pretimeout; + unsigned int min_pretimeout; + unsigned int max_pretimeout; void *driver_data; struct mutex lock; unsigned long status; @@ -75,6 +78,9 @@ It contains following fields: * timeout: the watchdog timer's timeout value (in seconds). * min_timeout: the watchdog timer's minimum timeout value (in seconds). * max_timeout: the watchdog timer's maximum timeout value (in seconds). +* pretimeout: the watchdog timer's pretimeout value (in seconds). +* min_pretimeout: the watchdog timer's minimum pretimeout value (in seconds). +* max_pretimeout: the watchdog timer's maximum pretimeout value (in seconds). * bootstatus: status of the device after booting (reported with watchdog WDIOF_* status bits). * driver_data: a pointer to the drivers private data of a watchdog device. @@ -99,6 +105,7 @@ struct watchdog_ops { int (*ping)(struct watchdog_device *); unsigned int (*status)(struct watchdog_device *); int (*set_timeout)(struct watchdog_device *, unsigned int); + int (*set_pretimeout)(struct watchdog_device *, unsigned int); unsigned int (*get_timeleft)(struct watchdog_device *); void (*ref)(struct watchdog_device *); void (*unref)(struct watchdog_device *); @@ -160,9 +167,19 @@ they are supported. These optional routines/operations are: and -EIO for "could not write value to the watchdog". On success this routine should set the timeout value of the watchdog_device to the achieved timeout value (which may be different from the requested one - because the watchdog does not necessarily has a 1 second resolution). + because the watchdog does not necessarily has a 1 second resolution; + If the driver supports pretimeout, then the timeout value must be greater + than that). (Note: the WDIOF_SETTIMEOUT needs to be set in the options field of the watchdog's info structure). +* set_pretimeout: this routine checks and changes the pretimeout of the + watchdog timer device. It returns 0 on success, -EINVAL for "parameter out of + range" and -EIO for "could not write value to the watchdog". On success this + routine should set the pretimeout value of the watchdog_device to the + achieved pretimeout value (which may be different from the requested one + because the watchdog does not necessarily has a 1 second resolution). + (Note: the WDIOF_PRETIMEOUT needs to be set in the options field of the + watchdog's info structure). * get_timeleft: this routines returns the time that's left before a reset. * ref: the operation that calls kref_get on the kref of a dynamically allocated watchdog_device struct. @@ -226,8 +243,28 @@ extern int watchdog_init_timeout(struct watchdog_device *wdd, unsigned int timeout_parm, struct device *dev); The watchdog_init_timeout function allows you to initialize the timeout field -using the module timeout parameter or by retrieving the timeout-sec property from -the device tree (if the module timeout parameter is invalid). Best practice is -to set the default timeout value as timeout value in the watchdog_device and -then use this function to set the user "preferred" timeout value. +using the module timeout parameter or by retrieving the first element of +the timeout-sec property from the device tree (if the module timeout parameter +is invalid). Best practice is to set the default timeout value as timeout value +in the watchdog_device and then use this function to set the user "preferred" +timeout value. +This routine returns zero on success and a negative errno code for failure. + +Some watchdog timers have two stage of timeouts (timeout and pretimeout), +to initialize the timeout and pretimeout fields at the same time, the following +function can be used: + +int watchdog_init_timeouts(struct watchdog_device *wdd, + unsigned int pretimeout_parm, + unsigned int timeout_parm, + struct device *dev); + +The watchdog_init_timeouts function allows you to initialize the pretimeout and +timeout fields using the module pretimeout and timeout parameter or by +retrieving the elements in the timeout-sec property (the first element is for +timeout, the second one is for pretimeout) from the device tree (if the module +pretimeout and timeout parameter are invalid). +Best practice is to set the default pretimeout and timeout value as pretimeout +and timeout value in the watchdog_device and then use this function to set the +user "preferred" pretimeout value. This routine returns zero on success and a negative errno code for failure. diff --git a/drivers/watchdog/watchdog_core.c b/drivers/watchdog/watchdog_core.c index 1a80594..280c399 100644 --- a/drivers/watchdog/watchdog_core.c +++ b/drivers/watchdog/watchdog_core.c @@ -85,57 +85,99 @@ static void watchdog_deferred_registration_del(struct watchdog_device *wdd) static void watchdog_check_min_max_timeout(struct watchdog_device *wdd) { /* - * Check that we have valid min and max timeout values, if - * not reset them both to 0 (=not used or unknown) + * Check that we have valid min and max pretimeout and timeout values, + * if not, reset them all to 0 (=not used or unknown) */ - if (wdd->min_timeout > wdd->max_timeout) { - pr_info("Invalid min and max timeout values, resetting to 0!\n"); + if (wdd->min_pretimeout > wdd->max_pretimeout || + wdd->min_timeout > wdd->max_timeout || + wdd->min_timeout < wdd->min_pretimeout || + wdd->max_timeout < wdd->max_pretimeout) { + pr_info("Invalid min or max timeouts, resetting to 0\n"); + wdd->min_pretimeout = 0; + wdd->max_pretimeout = 0; wdd->min_timeout = 0; wdd->max_timeout = 0; } } /** - * watchdog_init_timeout() - initialize the timeout field + * watchdog_init_timeouts() - initialize the pretimeout and timeout field + * @pretimeout_parm: pretimeout module parameter * @timeout_parm: timeout module parameter * @dev: Device that stores the timeout-sec property * - * Initialize the timeout field of the watchdog_device struct with either the - * timeout module parameter (if it is valid value) or the timeout-sec property - * (only if it is a valid value and the timeout_parm is out of bounds). - * If none of them are valid then we keep the old value (which should normally - * be the default timeout value. + * Initialize the pretimeout and timeout field of the watchdog_device struct + * with both the pretimeout and timeout module parameters (if they are valid) or + * the timeout-sec property (only if they are valid and the pretimeout_parm or + * timeout_parm is out of bounds). If one of them is invalid, then we keep + * the old value (which should normally be the default timeout value). * * A zero is returned on success and -EINVAL for failure. */ -int watchdog_init_timeout(struct watchdog_device *wdd, - unsigned int timeout_parm, struct device *dev) +int watchdog_init_timeouts(struct watchdog_device *wdd, + unsigned int pretimeout_parm, + unsigned int timeout_parm, + struct device *dev) { - unsigned int t = 0; - int ret = 0; + int ret = 0, length = 0; + u32 timeouts[2] = {0}; + struct property *prop; watchdog_check_min_max_timeout(wdd); - /* try to get the timeout module parameter first */ - if (!watchdog_timeout_invalid(wdd, timeout_parm) && timeout_parm) { - wdd->timeout = timeout_parm; - return ret; - } - if (timeout_parm) + /* + * Try to get the pretimeout module parameter first. + * Note: zero is a valid value for pretimeout. + */ + if (watchdog_pretimeout_invalid(wdd, pretimeout_parm)) + ret = -EINVAL; + + /* + * Try to get the timeout module parameter, + * if it's valid and pretimeout is valid(ret == 0), + * assignment and return zero. Otherwise, try dtb. + */ + if (timeout_parm && !ret) { + if (!watchdog_timeout_invalid(wdd, timeout_parm)) { + wdd->timeout = timeout_parm; + wdd->pretimeout = pretimeout_parm; + return 0; + } ret = -EINVAL; + } - /* try to get the timeout_sec property */ + /* + * Either at least one of the module parameters is invalid, + * or timeout_parm is 0. Try to get the timeout_sec property. + */ if (dev == NULL || dev->of_node == NULL) return ret; - of_property_read_u32(dev->of_node, "timeout-sec", &t); - if (!watchdog_timeout_invalid(wdd, t) && t) - wdd->timeout = t; - else - ret = -EINVAL; - return ret; + prop = of_find_property(dev->of_node, "timeout-sec", &length); + if (prop && length > 0 && length <= sizeof(u32) * 2) { + of_property_read_u32_array(dev->of_node, + "timeout-sec", timeouts, + length / sizeof(u32)); + if (length == sizeof(u32) * 2) { + if (watchdog_pretimeout_invalid(wdd, timeouts[1])) + return -EINVAL; + ret = 0; + } else { + ret = -EINVAL; + } + + if (!watchdog_timeout_invalid(wdd, timeouts[0]) && + timeouts[0]) { + wdd->timeout = timeouts[0]; + if (!ret) + wdd->pretimeout = timeouts[1]; + return 0; + } + } + + return -EINVAL; } -EXPORT_SYMBOL_GPL(watchdog_init_timeout); +EXPORT_SYMBOL_GPL(watchdog_init_timeouts); static int __watchdog_register_device(struct watchdog_device *wdd) { diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c index 6aaefba..af0777e 100644 --- a/drivers/watchdog/watchdog_dev.c +++ b/drivers/watchdog/watchdog_dev.c @@ -218,6 +218,38 @@ out_timeout: } /* + * watchdog_set_pretimeout: set the watchdog timer pretimeout + * @wddev: the watchdog device to set the timeout for + * @pretimeout: pretimeout to set in seconds + */ + +static int watchdog_set_pretimeout(struct watchdog_device *wddev, + unsigned int pretimeout) +{ + int err; + + if (!wddev->ops->set_pretimeout || + !(wddev->info->options & WDIOF_PRETIMEOUT)) + return -EOPNOTSUPP; + + if (watchdog_pretimeout_invalid(wddev, pretimeout)) + return -EINVAL; + + mutex_lock(&wddev->lock); + + if (test_bit(WDOG_UNREGISTERED, &wddev->status)) { + err = -ENODEV; + goto out_pretimeout; + } + + err = wddev->ops->set_pretimeout(wddev, pretimeout); + +out_pretimeout: + mutex_unlock(&wddev->lock); + return err; +} + +/* * watchdog_get_timeleft: wrapper to get the time left before a reboot * @wddev: the watchdog device to get the remaining time from * @timeleft: the time that's left @@ -388,6 +420,27 @@ static long watchdog_ioctl(struct file *file, unsigned int cmd, if (wdd->timeout == 0) return -EOPNOTSUPP; return put_user(wdd->timeout, p); + case WDIOC_SETPRETIMEOUT: + /* check if we support the pretimeout */ + if (!(wdd->info->options & WDIOF_PRETIMEOUT)) + return -EOPNOTSUPP; + if (get_user(val, p)) + return -EFAULT; + err = watchdog_set_pretimeout(wdd, val); + if (err < 0) + return err; + /* + * If the watchdog is active then we send a keepalive ping + * to make sure that the watchdog keeps running (and if + * possible that it takes the new pretimeout) + */ + watchdog_ping(wdd); + /* Fall */ + case WDIOC_GETPRETIMEOUT: + /* check if we support the pretimeout */ + if (wdd->info->options & WDIOF_PRETIMEOUT) + return put_user(wdd->pretimeout, p); + return -EOPNOTSUPP; case WDIOC_GETTIMELEFT: err = watchdog_get_timeleft(wdd, &val); if (err) diff --git a/include/linux/watchdog.h b/include/linux/watchdog.h index f47fead..bf2d9e9 100644 --- a/include/linux/watchdog.h +++ b/include/linux/watchdog.h @@ -25,6 +25,7 @@ struct watchdog_device; * @ping: The routine that sends a keepalive ping to the watchdog device. * @status: The routine that shows the status of the watchdog device. * @set_timeout:The routine for setting the watchdog devices timeout value. + * @set_pretimeout:The routine for setting the watchdog devices pretimeout value * @get_timeleft:The routine that get's the time that's left before a reset. * @ref: The ref operation for dyn. allocated watchdog_device structs * @unref: The unref operation for dyn. allocated watchdog_device structs @@ -44,6 +45,7 @@ struct watchdog_ops { int (*ping)(struct watchdog_device *); unsigned int (*status)(struct watchdog_device *); int (*set_timeout)(struct watchdog_device *, unsigned int); + int (*set_pretimeout)(struct watchdog_device *, unsigned int); unsigned int (*get_timeleft)(struct watchdog_device *); void (*ref)(struct watchdog_device *); void (*unref)(struct watchdog_device *); @@ -62,6 +64,9 @@ struct watchdog_ops { * @timeout: The watchdog devices timeout value. * @min_timeout:The watchdog devices minimum timeout value. * @max_timeout:The watchdog devices maximum timeout value. + * @pretimeout: The watchdog devices pretimeout value. + * @min_pretimeout:The watchdog devices minimum pretimeout value. + * @max_pretimeout:The watchdog devices maximum pretimeout value. * @driver-data:Pointer to the drivers private data. * @lock: Lock for watchdog core internal use only. * @status: Field that contains the devices internal status bits. @@ -88,6 +93,9 @@ struct watchdog_device { unsigned int timeout; unsigned int min_timeout; unsigned int max_timeout; + unsigned int pretimeout; + unsigned int min_pretimeout; + unsigned int max_pretimeout; void *driver_data; struct mutex lock; unsigned long status; @@ -119,8 +127,22 @@ static inline void watchdog_set_nowayout(struct watchdog_device *wdd, bool noway /* Use the following function to check if a timeout value is invalid */ static inline bool watchdog_timeout_invalid(struct watchdog_device *wdd, unsigned int t) { - return ((wdd->max_timeout != 0) && - (t < wdd->min_timeout || t > wdd->max_timeout)); + return (wdd->max_timeout && + (t < wdd->min_timeout || t > wdd->max_timeout)) || + (wdd->pretimeout && t <= wdd->pretimeout); +} + +/* + * Use the following function to check if a pretimeout value is invalid. + * It can be "0", that means we don't use pretimeout. + * This function returns false, when pretimeout is 0. + */ +static inline bool watchdog_pretimeout_invalid(struct watchdog_device *wdd, + unsigned int t) +{ + return t && ((wdd->max_pretimeout && + (t < wdd->min_pretimeout || t > wdd->max_pretimeout)) || + (wdd->timeout && t >= wdd->timeout)); } /* Use the following functions to manipulate watchdog driver specific data */ @@ -135,8 +157,17 @@ static inline void *watchdog_get_drvdata(struct watchdog_device *wdd) } /* drivers/watchdog/watchdog_core.c */ -extern int watchdog_init_timeout(struct watchdog_device *wdd, - unsigned int timeout_parm, struct device *dev); +int watchdog_init_timeouts(struct watchdog_device *wdd, + unsigned int pretimeout_parm, + unsigned int timeout_parm, + struct device *dev); +static inline int watchdog_init_timeout(struct watchdog_device *wdd, + unsigned int timeout_parm, + struct device *dev) +{ + return watchdog_init_timeouts(wdd, 0, timeout_parm, dev); +} + extern int watchdog_register_device(struct watchdog_device *); extern void watchdog_unregister_device(struct watchdog_device *);