[PATCH 2/2] watchdog: rti_wdt: Add reaction control to rti

Judith Mendez posted 2 patches 6 days, 9 hours ago
[PATCH 2/2] watchdog: rti_wdt: Add reaction control to rti
Posted by Judith Mendez 6 days, 9 hours ago
This allows to configure reaction between NMI and reset for WWD.

On K3 SoC's other than AM62l, watchdog reset output is routed to
the ESM module which can subsequently route the signal to safety
master or SoC reset. On AM62l [0], the watchdog reset output is routed
to the SoC HW reset block. So, add a new compatible for AM62l to
add SoC data and configure reaction to reset instead of NMI.

[0] https://www.ti.com/lit/pdf/sprujb4
Signed-off-by: Judith Mendez <jm@ti.com>
---
 drivers/watchdog/rti_wdt.c | 31 +++++++++++++++++++++++++++----
 1 file changed, 27 insertions(+), 4 deletions(-)

diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
index be7d7db475911..9b8d2ea2606c3 100644
--- a/drivers/watchdog/rti_wdt.c
+++ b/drivers/watchdog/rti_wdt.c
@@ -35,7 +35,8 @@
 #define RTIWWDRXCTRL	0xa4
 #define RTIWWDSIZECTRL	0xa8
 
-#define RTIWWDRX_NMI	0xa
+#define RTIWWDRXN_RST	0x5
+#define RTIWWDRXN_NMI	0xa
 
 #define RTIWWDSIZE_50P		0x50
 #define RTIWWDSIZE_25P		0x500
@@ -63,22 +64,29 @@
 
 static int heartbeat;
 
+struct rti_wdt_data {
+	bool reset;
+};
+
 /*
  * struct to hold data for each WDT device
  * @base - base io address of WD device
  * @freq - source clock frequency of WDT
  * @wdd  - hold watchdog device as is in WDT core
+ * @data - hold configuration data
  */
 struct rti_wdt_device {
 	void __iomem		*base;
 	unsigned long		freq;
 	struct watchdog_device	wdd;
+	const struct rti_wdt_data *data;
 };
 
 static int rti_wdt_start(struct watchdog_device *wdd)
 {
 	u32 timer_margin;
 	struct rti_wdt_device *wdt = watchdog_get_drvdata(wdd);
+	u8 reaction;
 	int ret;
 
 	ret = pm_runtime_resume_and_get(wdd->parent);
@@ -101,8 +109,12 @@ static int rti_wdt_start(struct watchdog_device *wdd)
 	 */
 	wdd->min_hw_heartbeat_ms = 520 * wdd->timeout + MAX_HW_ERROR;
 
-	/* Generate NMI when wdt expires */
-	writel_relaxed(RTIWWDRX_NMI, wdt->base + RTIWWDRXCTRL);
+	/* Generate reset or NMI when timer expires/serviced outside of window */
+	reaction = RTIWWDRXN_NMI;
+	if (wdt->data->reset)
+		reaction = RTIWWDRXN_RST;
+
+	writel_relaxed(reaction, wdt->base + RTIWWDRXCTRL);
 
 	/* Open window size 50%; this is the largest window size available */
 	writel_relaxed(RTIWWDSIZE_50P, wdt->base + RTIWWDSIZECTRL);
@@ -254,6 +266,8 @@ static int rti_wdt_probe(struct platform_device *pdev)
 	wdd->timeout = DEFAULT_HEARTBEAT;
 	wdd->parent = dev;
 
+	wdt->data = of_device_get_match_data(dev);
+
 	watchdog_set_drvdata(wdd, wdt);
 	watchdog_set_nowayout(wdd, 1);
 	watchdog_set_restart_priority(wdd, 128);
@@ -361,8 +375,17 @@ static void rti_wdt_remove(struct platform_device *pdev)
 	pm_runtime_disable(&pdev->dev);
 }
 
+static struct rti_wdt_data j7_wdt = {
+	.reset = false,
+};
+
+static struct rti_wdt_data am62l_wdt = {
+	.reset = true,
+};
+
 static const struct of_device_id rti_wdt_of_match[] = {
-	{ .compatible = "ti,j7-rti-wdt", },
+	{ .compatible = "ti,j7-rti-wdt", .data = &j7_wdt },
+	{ .compatible = "ti,am62l-rti-wdt", .data = &am62l_wdt },
 	{},
 };
 MODULE_DEVICE_TABLE(of, rti_wdt_of_match);
-- 
2.52.0