Use the bark interrupt as the pretimeout notifier if available.
By default, the pretimeout notification shall occur one second earlier
than the timeout.
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.
Signed-off-by: Wang Qing <[email protected]>
---
drivers/watchdog/mtk_wdt.c | 62 ++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 57 insertions(+), 5 deletions(-)
diff --git a/drivers/watchdog/mtk_wdt.c b/drivers/watchdog/mtk_wdt.c
index 97ca993..7bef1e3
--- a/drivers/watchdog/mtk_wdt.c
+++ b/drivers/watchdog/mtk_wdt.c
@@ -25,6 +25,7 @@
#include <linux/reset-controller.h>
#include <linux/types.h>
#include <linux/watchdog.h>
+#include <linux/interrupt.h>
#define WDT_MAX_TIMEOUT 31
#define WDT_MIN_TIMEOUT 1
@@ -234,18 +235,46 @@ static int mtk_wdt_start(struct watchdog_device *wdt_dev)
void __iomem *wdt_base = mtk_wdt->wdt_base;
int ret;
- ret = mtk_wdt_set_timeout(wdt_dev, wdt_dev->timeout);
+ ret = mtk_wdt_set_timeout(wdt_dev, wdt_dev->timeout - wdt_dev->pretimeout);
if (ret < 0)
return ret;
reg = ioread32(wdt_base + WDT_MODE);
- reg &= ~(WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN);
+ reg &= ~WDT_MODE_IRQ_EN;
+ if (wdt_dev->pretimeout)
+ reg |= WDT_MODE_IRQ_EN;
+ else
+ reg &= ~WDT_MODE_IRQ_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)
+{
+ wdd->pretimeout = timeout;
+ return mtk_wdt_start(wdd);
+}
+
+static irqreturn_t mtk_wdt_isr(int irq, void *arg)
+{
+ struct watchdog_device *wdd = arg;
+ struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdd);
+ void __iomem *wdt_base = mtk_wdt->wdt_base;
+
+ watchdog_notify_pretimeout(wdd);
+ /*
+ * Guaranteed to be reset when the timeout
+ * expires under any situations
+ */
+ mdelay(1000*wdd->pretimeout);
+ writel(WDT_SWRST_KEY, wdt_base + WDT_SWRST);
+
+ return IRQ_HANDLED;
+}
+
static const struct watchdog_info mtk_wdt_info = {
.identity = DRV_NAME,
.options = WDIOF_SETTIMEOUT |
@@ -253,12 +282,21 @@ 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 +305,7 @@ 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 +317,22 @@ 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 = 1;
+ } 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;
@@ -360,7 +413,6 @@ static struct platform_driver mtk_wdt_driver = {
};
module_platform_driver(mtk_wdt_driver);
-
module_param(timeout, uint, 0);
MODULE_PARM_DESC(timeout, "Watchdog heartbeat in seconds");
--
2.7.4