From patchwork Sun Apr 25 01:52:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qing Wang X-Patchwork-Id: 427430 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 48104C433B4 for ; Sun, 25 Apr 2021 01:52:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 26A1761494 for ; Sun, 25 Apr 2021 01:52:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230488AbhDYBw7 (ORCPT ); Sat, 24 Apr 2021 21:52:59 -0400 Received: from mail-m17640.qiye.163.com ([59.111.176.40]:9622 "EHLO mail-m17640.qiye.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229770AbhDYBw4 (ORCPT ); Sat, 24 Apr 2021 21:52:56 -0400 Received: from vivo-HP-ProDesk-680-G4-PCI-MT.vivo.xyz (unknown [58.251.74.232]) by mail-m17640.qiye.163.com (Hmail) with ESMTPA id 54C32540207; Sun, 25 Apr 2021 09:52:14 +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 V9 1/2] watchdog: mtk: support pre-timeout when the bark irq is available Date: Sun, 25 Apr 2021 09:52:06 +0800 Message-Id: <1619315527-8171-2-git-send-email-wangqing@vivo.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1619315527-8171-1-git-send-email-wangqing@vivo.com> References: <1619315527-8171-1-git-send-email-wangqing@vivo.com> X-HM-Spam-Status: e1kfGhgUHx5ZQUtXWQgYFAkeWUFZS1VLWVdZKFlBSE83V1ktWUFJV1kPCR oVCBIfWUFZGklNTFYeTU4YTUJDS0lOQx1VEwETFhoSFyQUDg9ZV1kWGg8SFR0UWUFZT0tIVUpKS0 hKTFVLWQY+ X-HM-Sender-Digest: e1kMHhlZQR0aFwgeV1kSHx4VD1lBWUc6MBA6TCo6IT8cFgMXFBgrVggp PjMwFBRVSlVKTUpCSEpOTkhOS0JIVTMWGhIXVQwaFRwKEhUcOw0SDRRVGBQWRVlXWRILWUFZTkNV SU5KVUxPVUlISVlXWQgBWUFNTktPNwY+ X-HM-Tid: 0a7906ba2b99d995kuws54c32540207 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(). V8/V9: - Fix some formatting problems. Signed-off-by: Wang Qing Reviewed-by: Guenter Roeck --- drivers/watchdog/mtk_wdt.c | 77 +++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 72 insertions(+), 5 deletions(-) diff --git a/drivers/watchdog/mtk_wdt.c b/drivers/watchdog/mtk_wdt.c index 97ca993..7bb0774 --- a/drivers/watchdog/mtk_wdt.c +++ b/drivers/watchdog/mtk_wdt.c @@ -25,9 +25,10 @@ #include #include #include +#include #define WDT_MAX_TIMEOUT 31 -#define WDT_MIN_TIMEOUT 1 +#define WDT_MIN_TIMEOUT 2 #define WDT_LENGTH_TIMEOUT(n) ((n) << 5) #define WDT_LENGTH 0x04 @@ -187,12 +188,19 @@ static int mtk_wdt_set_timeout(struct watchdog_device *wdt_dev, 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; /* * 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 - wdt_dev->pretimeout) << 6) + | WDT_LENGTH_KEY; iowrite32(reg, wdt_base + WDT_LENGTH); mtk_wdt_ping(wdt_dev); @@ -239,13 +247,48 @@ 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; + } + + reg |= WDT_MODE_KEY; + 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 +296,21 @@ 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 +319,7 @@ 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 +331,22 @@ 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;