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 983F7531B18; Thu, 17 Sep 2026 15:48:53 +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=1789660140; cv=none; b=Rg5CZX9tvv3WR//LmoABlILClDHpflt9lJfzixiUVTebZ98RCfLYiWZwN/coFuVDPDocB3DgG+/dKi0dBk0Hps1ByOxj2lVU2UDtPnOWxFv2qaXtwxqcu5Cg8dUHW1++dsiWxP2j1ZVH9dvn5Pp884p6RojsLXUnCshE8kCZOzc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789660140; c=relaxed/simple; bh=J14SDSePWRvVqw7au8fnOlqvHnhyk3WgV0UJuorh0yo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bYfJtwuH6DwROLHyw4d8QyENg2glFslop174G3vKCjkCanAM3zjxgoPYJbgnrHQpVEKRcF5ZWzUPl49CZM6DhzZ6pqIAjHBa0ZfNxMFNk9XlnG5ALlEPoKQmz+lE2KusFE2HKrrCM6I7Cw8ieLySTa24h6MqEiK3Y7m74At2Pe8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zH+YKmj2; 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="zH+YKmj2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B88571F00893; Thu, 17 Sep 2026 15:48:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789660133; bh=wlU3MMYV+eTsNhbijOtVHbw8vK+LrnIdaxNN6u+EvcM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=zH+YKmj26CFVngH6x+RNkYLXphDemH6QK3dDWwHc1QYklcyu+KoqeV+cRqztKj+V5 Ek+9Dw/uhM6WVKMsD2fFVC69EHfzlLnJiHetKupDFxX66VDbfHTj+PR+ijytGaNVXQ a2VS9tyY/Oukv+aSLPxwdCZvazwoUSlakBy5pSbo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, James Hilliard , Guenter Roeck Subject: [PATCH 7.2 489/733] watchdog: sunxi_wdt: preserve boot-enabled watchdog Date: Thu, 17 Sep 2026 16:13:17 +0100 Message-ID: <20260917151404.235331467@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260917151350.597953846@linuxfoundation.org> References: <20260917151350.597953846@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 7.2-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 @@ -128,6 +128,38 @@ 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) { @@ -259,6 +291,7 @@ 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); @@ -286,7 +319,17 @@ 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);