From patchwork Fri Apr 23 02:53:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qing Wang X-Patchwork-Id: 426620 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 96598C43461 for ; Fri, 23 Apr 2021 03:00:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6CC186145D for ; Fri, 23 Apr 2021 03:00:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240166AbhDWDBO (ORCPT ); Thu, 22 Apr 2021 23:01:14 -0400 Received: from mail-m17640.qiye.163.com ([59.111.176.40]:34836 "EHLO mail-m17640.qiye.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238001AbhDWDBN (ORCPT ); Thu, 22 Apr 2021 23:01:13 -0400 Received: from vivo-HP-ProDesk-680-G4-PCI-MT.vivo.xyz (unknown [58.250.176.229]) by mail-m17640.qiye.163.com (Hmail) with ESMTPA id 3ABE2540162; Fri, 23 Apr 2021 10:53:41 +0800 (CST) From: Wang Qing To: Wim Van Sebroeck , Guenter Roeck , Rob Herring , Matthias Brugger , linux-watchdog@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Wang Qing Subject: [PATCH V7 1/2] watchdog: mtk: support pre-timeout when the bark irq is available Date: Fri, 23 Apr 2021 10:53:22 +0800 Message-Id: <1619146403-12769-2-git-send-email-wangqing@vivo.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1619146403-12769-1-git-send-email-wangqing@vivo.com> References: <1619146403-12769-1-git-send-email-wangqing@vivo.com> X-HM-Spam-Status: e1kfGhgUHx5ZQUtXWQgYFAkeWUFZS1VLWVdZKFlBSE83V1ktWUFJV1kPCR oVCBIfWUFZGR8dTFZKH0JPH0hMTxpDTB9VEwETFhoSFyQUDg9ZV1kWGg8SFR0UWUFZT0tIVUpKS0 hKTFVLWQY+ X-HM-Sender-Digest: e1kMHhlZQR0aFwgeV1kSHx4VD1lBWUc6NRA6Aww*SD8KHg03FjcxEC5W UU0KCRlVSlVKTUpCSk9NT0lJTkJNVTMWGhIXVQwaFRwKEhUcOw0SDRRVGBQWRVlXWRILWUFZTkNV SU5LVUpMTVVJSUJZV1kIAVlBTU5KTTcG X-HM-Tid: 0a78fca5b60fd995kuws3abe2540162 Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org Use the bark interrupt as the pretimeout notifier if available. When the watchdog timer expires in dual mode, an interrupt will be triggered first, then the timing restarts. The reset signal will be initiated when the timer expires again. The pretimeout notification shall occur at timeout-sec/2. V2: - panic() by default if WATCHDOG_PRETIMEOUT_GOV is not enabled. V3: - Modify the pretimeout behavior, manually reset after the pretimeout - is processed and wait until timeout. V4: - Remove pretimeout related processing. - Add dual mode control separately. V5: - Fix some formatting and printing problems. V6: - Realize pretimeout processing through dualmode. V7: - Add set_pretimeout(). Signed-off-by: Wang Qing --- drivers/watchdog/mtk_wdt.c | 76 +++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 71 insertions(+), 5 deletions(-) diff --git a/drivers/watchdog/mtk_wdt.c b/drivers/watchdog/mtk_wdt.c index 97ca993..ab3ac5d --- a/drivers/watchdog/mtk_wdt.c +++ b/drivers/watchdog/mtk_wdt.c @@ -25,6 +25,7 @@ #include #include #include +#include #define WDT_MAX_TIMEOUT 31 #define WDT_MIN_TIMEOUT 1 @@ -184,15 +185,23 @@ static int mtk_wdt_set_timeout(struct watchdog_device *wdt_dev, { struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdt_dev); void __iomem *wdt_base = mtk_wdt->wdt_base; + unsigned int timeout_interval = timeout; u32 reg; wdt_dev->timeout = timeout; - + /* + * In dual mode, irq will be triggered at timeout / 2 + * the real timeout occurs at timeout + */ + if (wdt_dev->pretimeout) { + wdt_dev->pretimeout = timeout / 2; + timeout_interval = wdt_dev->pretimeout; + } /* * One bit is the value of 512 ticks * The clock has 32 KHz */ - reg = WDT_LENGTH_TIMEOUT(timeout << 6) | WDT_LENGTH_KEY; + reg = WDT_LENGTH_TIMEOUT(timeout_interval << 6) | WDT_LENGTH_KEY; iowrite32(reg, wdt_base + WDT_LENGTH); mtk_wdt_ping(wdt_dev); @@ -239,13 +248,46 @@ static int mtk_wdt_start(struct watchdog_device *wdt_dev) return ret; reg = ioread32(wdt_base + WDT_MODE); - reg &= ~(WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN); + if (wdt_dev->pretimeout) + reg |= (WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN); + else + reg &= ~(WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN); reg |= (WDT_MODE_EN | WDT_MODE_KEY); iowrite32(reg, wdt_base + WDT_MODE); return 0; } +static int mtk_wdt_set_pretimeout(struct watchdog_device *wdd, + unsigned int timeout) +{ + struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdd); + void __iomem *wdt_base = mtk_wdt->wdt_base; + u32 reg = ioread32(wdt_base + WDT_MODE); + + if (timeout && !wdd->pretimeout) { + wdd->pretimeout = wdd->timeout / 2; + reg |= (WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN); + } else if (!timeout && wdd->pretimeout) { + wdd->pretimeout = 0; + reg &= ~(WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN); + } else + return 0; + + iowrite32(reg, wdt_base + WDT_MODE); + + return mtk_wdt_set_timeout(wdd, wdd->timeout); +} + +static irqreturn_t mtk_wdt_isr(int irq, void *arg) +{ + struct watchdog_device *wdd = arg; + + watchdog_notify_pretimeout(wdd); + + return IRQ_HANDLED; +} + static const struct watchdog_info mtk_wdt_info = { .identity = DRV_NAME, .options = WDIOF_SETTIMEOUT | @@ -253,12 +295,21 @@ static const struct watchdog_info mtk_wdt_info = { WDIOF_MAGICCLOSE, }; +static const struct watchdog_info mtk_wdt_pt_info = { + .identity = DRV_NAME, + .options = WDIOF_SETTIMEOUT | + WDIOF_PRETIMEOUT | + WDIOF_KEEPALIVEPING | + WDIOF_MAGICCLOSE, +}; + static const struct watchdog_ops mtk_wdt_ops = { .owner = THIS_MODULE, .start = mtk_wdt_start, .stop = mtk_wdt_stop, .ping = mtk_wdt_ping, .set_timeout = mtk_wdt_set_timeout, + .set_pretimeout = mtk_wdt_set_pretimeout, .restart = mtk_wdt_restart, }; @@ -267,7 +318,7 @@ static int mtk_wdt_probe(struct platform_device *pdev) struct device *dev = &pdev->dev; struct mtk_wdt_dev *mtk_wdt; const struct mtk_wdt_data *wdt_data; - int err; + int err, irq; mtk_wdt = devm_kzalloc(dev, sizeof(*mtk_wdt), GFP_KERNEL); if (!mtk_wdt) @@ -279,7 +330,22 @@ static int mtk_wdt_probe(struct platform_device *pdev) if (IS_ERR(mtk_wdt->wdt_base)) return PTR_ERR(mtk_wdt->wdt_base); - mtk_wdt->wdt_dev.info = &mtk_wdt_info; + irq = platform_get_irq(pdev, 0); + if (irq > 0) { + err = devm_request_irq(&pdev->dev, irq, mtk_wdt_isr, 0, "wdt_bark", + &mtk_wdt->wdt_dev); + if (err) + return err; + + mtk_wdt->wdt_dev.info = &mtk_wdt_pt_info; + mtk_wdt->wdt_dev.pretimeout = WDT_MAX_TIMEOUT / 2; + } else { + if (irq == -EPROBE_DEFER) + return -EPROBE_DEFER; + + mtk_wdt->wdt_dev.info = &mtk_wdt_info; + } + mtk_wdt->wdt_dev.ops = &mtk_wdt_ops; mtk_wdt->wdt_dev.timeout = WDT_MAX_TIMEOUT; mtk_wdt->wdt_dev.max_hw_heartbeat_ms = WDT_MAX_TIMEOUT * 1000;