From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2D8AB18C332; Wed, 30 Sep 2026 15:45:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790783140; cv=none; b=cvMrerXzMNof/ETHrdysgMtaLJMduY+vUEAPUFWVVIGrNbOtFvai3ieduUesw2Vc+GeOC1PFNQPcvQUYrIn8OjWeegvBUF2xvqYwnzDrO0qlrTO5/bII5ye/XgGYrkgvV0a0SlqE+GWSvNQwwxUnceN9apwBi24iTnyh+CzzTrk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790783140; c=relaxed/simple; bh=G5fxVJBThI/CtXrzLFLEtaI+XAIe/F9hlhlhUmIm5xY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DiZYx7Fq6dZffDW7GNwi1gv5rxIzhjAJvOm2mBJjEA0rxtxTKdd/GQrNweKcvlm1Ty4/XOiwuyJ/YMR2O3SIxg9xNIs94P/sozqNIH0FtTWakeqwwpGeGFVnlBEVBNcSQUtKLgCj29f2Sm18inA8H8+JltpTbicznnIURMNzh5A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jTQ6e7Xs; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="jTQ6e7Xs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 076781F0089B; Wed, 30 Sep 2026 15:45:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790783134; bh=V56KL13vwebt9P207CeHZOUSD0yLZGSspBL+tKx8CDY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=jTQ6e7XsimJhsiya+zO6BkfhKhe3AXGPTBWRdaWSMXskqgJbNpKNZ28js6E5skOKL bXIhcE5uAK7x+IUuJApj/CU/Pg6VHX/0i0kNyzGuf4tgiIybbVz/LreTmmf22NY6Cr bfWFbMe8HKwUACJc78B38HE6hHdEZLLpcdEBlyu4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, James Hilliard , Guenter Roeck Subject: [PATCH 5.10 291/595] watchdog: sunxi_wdt: preserve boot-enabled watchdog Date: Wed, 30 Sep 2026 17:23:04 +0200 Message-ID: <20260930152353.955146806@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152347.700140858@linuxfoundation.org> References: <20260930152347.700140858@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: James Hilliard commit aab55360fa11a2c054798a484ac67ad606f563e4 upstream. sunxi_wdt_probe() unconditionally stops the watchdog even when firmware left it running. This opens an unprotected interval during boot and prevents CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED from taking over the active watchdog. Detect an enabled watchdog and decode its programmed interval. Preserve representable timeouts, and round the 0.5-second interval up to the minimum representable one-second timeout. Use the configured timeout for reserved interval encodings. Set the Linux reset mode and ping the watchdog without clearing its enable bit, then mark it hardware-running before registration so the watchdog core services it until userspace takes control. Leave disabled watchdogs untouched. Fixes: d00680ed0026 ("watchdog: sunxi: New watchdog driver for Allwinner A10/A13") Cc: stable@vger.kernel.org Signed-off-by: James Hilliard Link: https://patch.msgid.link/20260827-submit-sunxi-wdt-boot-enabled-v1-v2-1-610d37dccc97@gmail.com Signed-off-by: Guenter Roeck Signed-off-by: Greg Kroah-Hartman --- drivers/watchdog/sunxi_wdt.c | 45 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 44 insertions(+), 1 deletion(-) --- a/drivers/watchdog/sunxi_wdt.c +++ b/drivers/watchdog/sunxi_wdt.c @@ -125,6 +125,38 @@ static int sunxi_wdt_ping(struct watchdo return 0; } +static bool sunxi_wdt_is_running(struct watchdog_device *wdt_dev) +{ + struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev); + const struct sunxi_wdt_reg *regs = sunxi_wdt->wdt_regs; + + return readl(sunxi_wdt->wdt_base + regs->wdt_mode) & WDT_MODE_EN; +} + +static unsigned int sunxi_wdt_get_timeout(struct watchdog_device *wdt_dev) +{ + struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev); + const struct sunxi_wdt_reg *regs = sunxi_wdt->wdt_regs; + unsigned int timeout; + u32 interval; + + interval = readl(sunxi_wdt->wdt_base + regs->wdt_mode); + interval >>= regs->wdt_timeout_shift; + interval &= WDT_TIMEOUT_MASK; + /* Round the 0.5-second interval up to the minimum representable timeout. */ + if (!interval) + return WDT_MIN_TIMEOUT; + + for (timeout = WDT_MIN_TIMEOUT; + timeout < ARRAY_SIZE(wdt_timeout_map); timeout++) { + if (wdt_timeout_map[timeout] == interval) + return timeout; + } + + /* Reserved interval encoding. */ + return 0; +} + static int sunxi_wdt_set_timeout(struct watchdog_device *wdt_dev, unsigned int timeout) { @@ -231,6 +263,7 @@ static int sunxi_wdt_probe(struct platfo { struct device *dev = &pdev->dev; struct sunxi_wdt_dev *sunxi_wdt; + unsigned int running_timeout; int err; sunxi_wdt = devm_kzalloc(dev, sizeof(*sunxi_wdt), GFP_KERNEL); @@ -258,7 +291,17 @@ static int sunxi_wdt_probe(struct platfo watchdog_set_drvdata(&sunxi_wdt->wdt_dev, sunxi_wdt); - sunxi_wdt_stop(&sunxi_wdt->wdt_dev); + if (sunxi_wdt_is_running(&sunxi_wdt->wdt_dev)) { + running_timeout = sunxi_wdt_get_timeout(&sunxi_wdt->wdt_dev); + if (running_timeout) + sunxi_wdt->wdt_dev.timeout = running_timeout; + + err = sunxi_wdt_start(&sunxi_wdt->wdt_dev); + if (err) + return err; + + set_bit(WDOG_HW_RUNNING, &sunxi_wdt->wdt_dev.status); + } watchdog_stop_on_reboot(&sunxi_wdt->wdt_dev); err = devm_watchdog_register_device(dev, &sunxi_wdt->wdt_dev);