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 <jorge.ramirez-ortiz@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20190906205411.31666-2-jorge.ramirez-ortiz@linaro.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
This commit is contained in:
Jorge Ramirez-Ortiz 2019-09-06 22:54:10 +02:00 committed by Wim Van Sebroeck
parent 3b7c09fd64
commit 36375491a4

View File

@ -1,8 +1,10 @@
// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2014, The Linux Foundation. All rights reserved.
*/
#include <linux/bits.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
@ -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;