From 36375491a439565402d1cb2cf12955c11f2ed5a6 Mon Sep 17 00:00:00 2001 From: Jorge Ramirez-Ortiz Date: Fri, 6 Sep 2019 22:54:10 +0200 Subject: [PATCH] watchdog: qcom: support pre-timeout when the bark irq is available Use the bark interrupt as the pre-timeout notifier whenever this interrupt is available. By default, the pretimeout notification shall occur one second earlier than the timeout. Signed-off-by: Jorge Ramirez-Ortiz Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20190906205411.31666-2-jorge.ramirez-ortiz@linaro.org Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/qcom-wdt.c | 69 ++++++++++++++++++++++++++++++++++--- 1 file changed, 64 insertions(+), 5 deletions(-) diff --git a/drivers/watchdog/qcom-wdt.c b/drivers/watchdog/qcom-wdt.c index 7be7f87be28f..aa22e625144a 100644 --- a/drivers/watchdog/qcom-wdt.c +++ b/drivers/watchdog/qcom-wdt.c @@ -1,8 +1,10 @@ // SPDX-License-Identifier: GPL-2.0-only /* Copyright (c) 2014, The Linux Foundation. All rights reserved. */ +#include #include #include +#include #include #include #include @@ -19,6 +21,9 @@ enum wdt_reg { WDT_BITE_TIME, }; +#define QCOM_WDT_ENABLE BIT(0) +#define QCOM_WDT_ENABLE_IRQ BIT(1) + static const u32 reg_offset_data_apcs_tmr[] = { [WDT_RST] = 0x38, [WDT_EN] = 0x40, @@ -54,15 +59,35 @@ struct qcom_wdt *to_qcom_wdt(struct watchdog_device *wdd) return container_of(wdd, struct qcom_wdt, wdd); } +static inline int qcom_get_enable(struct watchdog_device *wdd) +{ + int enable = QCOM_WDT_ENABLE; + + if (wdd->pretimeout) + enable |= QCOM_WDT_ENABLE_IRQ; + + return enable; +} + +static irqreturn_t qcom_wdt_isr(int irq, void *arg) +{ + struct watchdog_device *wdd = arg; + + watchdog_notify_pretimeout(wdd); + + return IRQ_HANDLED; +} + static int qcom_wdt_start(struct watchdog_device *wdd) { struct qcom_wdt *wdt = to_qcom_wdt(wdd); + unsigned int bark = wdd->timeout - wdd->pretimeout; writel(0, wdt_addr(wdt, WDT_EN)); writel(1, wdt_addr(wdt, WDT_RST)); - writel(wdd->timeout * wdt->rate, wdt_addr(wdt, WDT_BARK_TIME)); + writel(bark * wdt->rate, wdt_addr(wdt, WDT_BARK_TIME)); writel(wdd->timeout * wdt->rate, wdt_addr(wdt, WDT_BITE_TIME)); - writel(1, wdt_addr(wdt, WDT_EN)); + writel(qcom_get_enable(wdd), wdt_addr(wdt, WDT_EN)); return 0; } @@ -89,6 +114,13 @@ static int qcom_wdt_set_timeout(struct watchdog_device *wdd, return qcom_wdt_start(wdd); } +static int qcom_wdt_set_pretimeout(struct watchdog_device *wdd, + unsigned int timeout) +{ + wdd->pretimeout = timeout; + return qcom_wdt_start(wdd); +} + static int qcom_wdt_restart(struct watchdog_device *wdd, unsigned long action, void *data) { @@ -105,7 +137,7 @@ static int qcom_wdt_restart(struct watchdog_device *wdd, unsigned long action, writel(1, wdt_addr(wdt, WDT_RST)); writel(timeout, wdt_addr(wdt, WDT_BARK_TIME)); writel(timeout, wdt_addr(wdt, WDT_BITE_TIME)); - writel(1, wdt_addr(wdt, WDT_EN)); + writel(QCOM_WDT_ENABLE, wdt_addr(wdt, WDT_EN)); /* * Actually make sure the above sequence hits hardware before sleeping. @@ -121,6 +153,7 @@ static const struct watchdog_ops qcom_wdt_ops = { .stop = qcom_wdt_stop, .ping = qcom_wdt_ping, .set_timeout = qcom_wdt_set_timeout, + .set_pretimeout = qcom_wdt_set_pretimeout, .restart = qcom_wdt_restart, .owner = THIS_MODULE, }; @@ -133,6 +166,15 @@ static const struct watchdog_info qcom_wdt_info = { .identity = KBUILD_MODNAME, }; +static const struct watchdog_info qcom_wdt_pt_info = { + .options = WDIOF_KEEPALIVEPING + | WDIOF_MAGICCLOSE + | WDIOF_SETTIMEOUT + | WDIOF_PRETIMEOUT + | WDIOF_CARDRESET, + .identity = KBUILD_MODNAME, +}; + static void qcom_clk_disable_unprepare(void *data) { clk_disable_unprepare(data); @@ -146,7 +188,7 @@ static int qcom_wdt_probe(struct platform_device *pdev) struct device_node *np = dev->of_node; const u32 *regs; u32 percpu_offset; - int ret; + int irq, ret; regs = of_device_get_match_data(dev); if (!regs) { @@ -204,7 +246,24 @@ static int qcom_wdt_probe(struct platform_device *pdev) return -EINVAL; } - wdt->wdd.info = &qcom_wdt_info; + /* check if there is pretimeout support */ + irq = platform_get_irq(pdev, 0); + if (irq > 0) { + ret = devm_request_irq(dev, irq, qcom_wdt_isr, + IRQF_TRIGGER_RISING, + "wdt_bark", &wdt->wdd); + if (ret) + return ret; + + wdt->wdd.info = &qcom_wdt_pt_info; + wdt->wdd.pretimeout = 1; + } else { + if (irq == -EPROBE_DEFER) + return -EPROBE_DEFER; + + wdt->wdd.info = &qcom_wdt_info; + } + wdt->wdd.ops = &qcom_wdt_ops; wdt->wdd.min_timeout = 1; wdt->wdd.max_timeout = 0x10000000U / wdt->rate;