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* [PATCH V7,RESEND 0/2] watchdog: mtk: support pre-timeout when the bark irq is available
@ 2021-04-23  3:20 Wang Qing
  2021-04-23  3:20 ` [PATCH V7,RESEND 1/2] " Wang Qing
  2021-04-23  3:20 ` [PATCH V7,RESEND 2/2] doc: mtk-wdt: " Wang Qing
  0 siblings, 2 replies; 4+ messages in thread
From: Wang Qing @ 2021-04-23  3:20 UTC (permalink / raw)
  To: Wim Van Sebroeck, Guenter Roeck, Rob Herring, Matthias Brugger,
	linux-watchdog, devicetree, linux-arm-kernel, linux-mediatek,
	linux-kernel
  Cc: Wang Qing

Use the bark interrupt as the pretimeout notifier if available.
The pretimeout notification shall occur at timeout-sec/2.

Wang Qing (2):
  watchdog: mtk: support pre-timeout when the bark irq is available
  doc: mtk-wdt: support pre-timeout when the bark irq is available

 .../devicetree/bindings/watchdog/mtk-wdt.txt       |  5 ++
 drivers/watchdog/mtk_wdt.c                         | 76 ++++++++++++++++++++--
 2 files changed, 76 insertions(+), 5 deletions(-)

-- 
2.7.4


^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH V7,RESEND 1/2] watchdog: mtk: support pre-timeout when the bark irq is available
  2021-04-23  3:20 [PATCH V7,RESEND 0/2] watchdog: mtk: support pre-timeout when the bark irq is available Wang Qing
@ 2021-04-23  3:20 ` Wang Qing
  2021-04-23  3:20 ` [PATCH V7,RESEND 2/2] doc: mtk-wdt: " Wang Qing
  1 sibling, 0 replies; 4+ messages in thread
From: Wang Qing @ 2021-04-23  3:20 UTC (permalink / raw)
  To: Wim Van Sebroeck, Guenter Roeck, Rob Herring, Matthias Brugger,
	linux-watchdog, devicetree, linux-arm-kernel, linux-mediatek,
	linux-kernel
  Cc: Wang Qing

Use the bark interrupt as the pretimeout notifier if available.

When the watchdog timer expires in dual mode, an interrupt will be
triggered first, then the timing restarts. The reset signal will be
initiated when the timer expires again.

The pretimeout notification shall occur at timeout-sec/2.

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.

V4:
- Remove pretimeout related processing. 
- Add dual mode control separately.

V5:
- Fix some formatting and printing problems.

V6:
- Realize pretimeout processing through dualmode.

V7:
- Add set_pretimeout().

Signed-off-by: Wang Qing <wangqing@vivo.com>
---
 drivers/watchdog/mtk_wdt.c | 76 +++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 71 insertions(+), 5 deletions(-)

diff --git a/drivers/watchdog/mtk_wdt.c b/drivers/watchdog/mtk_wdt.c
index 97ca993..ab3ac5d
--- 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
@@ -184,15 +185,23 @@ static int mtk_wdt_set_timeout(struct watchdog_device *wdt_dev,
 {
 	struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdt_dev);
 	void __iomem *wdt_base = mtk_wdt->wdt_base;
+	unsigned int timeout_interval = timeout;
 	u32 reg;
 
 	wdt_dev->timeout = timeout;
-
+	/*
+	 * In dual mode, irq will be triggered at timeout / 2
+	 * the real timeout occurs at timeout
+	 */
+	if (wdt_dev->pretimeout) {
+		wdt_dev->pretimeout = timeout / 2;
+		timeout_interval = wdt_dev->pretimeout;
+	}
 	/*
 	 * One bit is the value of 512 ticks
 	 * The clock has 32 KHz
 	 */
-	reg = WDT_LENGTH_TIMEOUT(timeout << 6) | WDT_LENGTH_KEY;
+	reg = WDT_LENGTH_TIMEOUT(timeout_interval << 6) | WDT_LENGTH_KEY;
 	iowrite32(reg, wdt_base + WDT_LENGTH);
 
 	mtk_wdt_ping(wdt_dev);
@@ -239,13 +248,46 @@ static int mtk_wdt_start(struct watchdog_device *wdt_dev)
 		return ret;
 
 	reg = ioread32(wdt_base + WDT_MODE);
-	reg &= ~(WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN);
+	if (wdt_dev->pretimeout)
+		reg |= (WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN);
+	else
+		reg &= ~(WDT_MODE_IRQ_EN | WDT_MODE_DUAL_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)
+{
+	struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdd);
+	void __iomem *wdt_base = mtk_wdt->wdt_base;
+	u32 reg = ioread32(wdt_base + WDT_MODE);
+
+	if (timeout && !wdd->pretimeout) {
+		wdd->pretimeout = wdd->timeout / 2;
+		reg |= (WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN | WDT_MODE_KEY);
+	} else if (!timeout && wdd->pretimeout) {
+		wdd->pretimeout = 0;
+		reg &= ~(WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN | WDT_MODE_KEY);
+	} else
+		return 0;
+
+	iowrite32(reg, wdt_base + WDT_MODE);
+
+	return mtk_wdt_set_timeout(wdd, wdd->timeout);
+}
+
+static irqreturn_t mtk_wdt_isr(int irq, void *arg)
+{
+	struct watchdog_device *wdd = arg;
+
+	watchdog_notify_pretimeout(wdd);
+
+	return IRQ_HANDLED;
+}
+
 static const struct watchdog_info mtk_wdt_info = {
 	.identity	= DRV_NAME,
 	.options	= WDIOF_SETTIMEOUT |
@@ -253,12 +295,21 @@ 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 +318,7 @@ 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 +330,22 @@ 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 = WDT_MAX_TIMEOUT / 2;
+	} 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;
-- 
2.7.4


^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH V7,RESEND 2/2] doc: mtk-wdt: support pre-timeout when the bark irq is available
  2021-04-23  3:20 [PATCH V7,RESEND 0/2] watchdog: mtk: support pre-timeout when the bark irq is available Wang Qing
  2021-04-23  3:20 ` [PATCH V7,RESEND 1/2] " Wang Qing
@ 2021-04-23  3:20 ` Wang Qing
  2021-04-23 17:39   ` [PATCH V7, RESEND " Rob Herring
  1 sibling, 1 reply; 4+ messages in thread
From: Wang Qing @ 2021-04-23  3:20 UTC (permalink / raw)
  To: Wim Van Sebroeck, Guenter Roeck, Rob Herring, Matthias Brugger,
	linux-watchdog, devicetree, linux-arm-kernel, linux-mediatek,
	linux-kernel
  Cc: Wang Qing

Add description of pre-timeout in mtk-wdt.

Signed-off-by: Wang Qing <wangqing@vivo.com>
---
 Documentation/devicetree/bindings/watchdog/mtk-wdt.txt | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Documentation/devicetree/bindings/watchdog/mtk-wdt.txt b/Documentation/devicetree/bindings/watchdog/mtk-wdt.txt
index e36ba60..8e27777
--- a/Documentation/devicetree/bindings/watchdog/mtk-wdt.txt
+++ b/Documentation/devicetree/bindings/watchdog/mtk-wdt.txt
@@ -1,5 +1,8 @@
 Mediatek SoCs Watchdog timer
 
+The watchdog supports a pre-timeout interrupt that fires timeout-sec/2
+before the expiry.
+
 Required properties:
 
 - compatible should contain:
@@ -17,6 +20,7 @@ Required properties:
 - reg : Specifies base physical address and size of the registers.
 
 Optional properties:
+- interrupts: Watchdog pre-timeout (bark) interrupt.
 - timeout-sec: contains the watchdog timeout in seconds.
 - #reset-cells: Should be 1.
 
@@ -26,6 +30,7 @@ watchdog: watchdog@10007000 {
 	compatible = "mediatek,mt8183-wdt",
 		     "mediatek,mt6589-wdt";
 	reg = <0 0x10007000 0 0x100>;
+	interrupts = <GIC_SPI 139 IRQ_TYPE_NONE>;
 	timeout-sec = <10>;
 	#reset-cells = <1>;
 };
-- 
2.7.4


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH V7, RESEND 2/2] doc: mtk-wdt: support pre-timeout when the bark irq is available
  2021-04-23  3:20 ` [PATCH V7,RESEND 2/2] doc: mtk-wdt: " Wang Qing
@ 2021-04-23 17:39   ` Rob Herring
  0 siblings, 0 replies; 4+ messages in thread
From: Rob Herring @ 2021-04-23 17:39 UTC (permalink / raw)
  To: Wang Qing
  Cc: Rob Herring, linux-arm-kernel, Guenter Roeck, linux-watchdog,
	Matthias Brugger, linux-mediatek, Wim Van Sebroeck, linux-kernel,
	devicetree

On Fri, 23 Apr 2021 11:20:20 +0800, Wang Qing wrote:
> Add description of pre-timeout in mtk-wdt.
> 
> Signed-off-by: Wang Qing <wangqing@vivo.com>
> ---
>  Documentation/devicetree/bindings/watchdog/mtk-wdt.txt | 5 +++++
>  1 file changed, 5 insertions(+)
> 

Acked-by: Rob Herring <robh@kernel.org>

^ permalink raw reply	[flat|nested] 4+ messages in thread

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Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2021-04-23  3:20 [PATCH V7,RESEND 0/2] watchdog: mtk: support pre-timeout when the bark irq is available Wang Qing
2021-04-23  3:20 ` [PATCH V7,RESEND 1/2] " Wang Qing
2021-04-23  3:20 ` [PATCH V7,RESEND 2/2] doc: mtk-wdt: " Wang Qing
2021-04-23 17:39   ` [PATCH V7, RESEND " Rob Herring

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