watchdog: aspeed: Enable pre-timeout interrupt

Enable the core pre-timeout interrupt on AST2500 and AST2600.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20221101205338.577427-2-eajames@linux.ibm.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c
index 0cff2ad..86b5331 100644 (file)
--- a/drivers/watchdog/aspeed_wdt.c
+++ b/drivers/watchdog/aspeed_wdt.c
@@ -5,11 +5,14 @@
  * Joel Stanley <joel@jms.id.au>
  */
 
+#include <linux/bits.h>
 #include <linux/delay.h>
+#include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_irq.h>
 #include <linux/platform_device.h>
 #include <linux/watchdog.h>
 
@@ -18,28 +21,41 @@ module_param(nowayout, bool, 0);
 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
                                __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 
+struct aspeed_wdt_config {
+       u32 ext_pulse_width_mask;
+       u32 irq_shift;
+       u32 irq_mask;
+};
+
 struct aspeed_wdt {
        struct watchdog_device  wdd;
        void __iomem            *base;
        u32                     ctrl;
-};
-
-struct aspeed_wdt_config {
-       u32 ext_pulse_width_mask;
+       const struct aspeed_wdt_config *cfg;
 };
 
 static const struct aspeed_wdt_config ast2400_config = {
        .ext_pulse_width_mask = 0xff,
+       .irq_shift = 0,
+       .irq_mask = 0,
 };
 
 static const struct aspeed_wdt_config ast2500_config = {
        .ext_pulse_width_mask = 0xfffff,
+       .irq_shift = 12,
+       .irq_mask = GENMASK(31, 12),
+};
+
+static const struct aspeed_wdt_config ast2600_config = {
+       .ext_pulse_width_mask = 0xfffff,
+       .irq_shift = 0,
+       .irq_mask = GENMASK(31, 10),
 };
 
 static const struct of_device_id aspeed_wdt_of_table[] = {
        { .compatible = "aspeed,ast2400-wdt", .data = &ast2400_config },
        { .compatible = "aspeed,ast2500-wdt", .data = &ast2500_config },
-       { .compatible = "aspeed,ast2600-wdt", .data = &ast2500_config },
+       { .compatible = "aspeed,ast2600-wdt", .data = &ast2600_config },
        { },
 };
 MODULE_DEVICE_TABLE(of, aspeed_wdt_of_table);
@@ -58,6 +74,7 @@ MODULE_DEVICE_TABLE(of, aspeed_wdt_of_table);
 #define   WDT_CTRL_RESET_SYSTEM                BIT(1)
 #define   WDT_CTRL_ENABLE              BIT(0)
 #define WDT_TIMEOUT_STATUS     0x10
+#define   WDT_TIMEOUT_STATUS_IRQ               BIT(2)
 #define   WDT_TIMEOUT_STATUS_BOOT_SECONDARY    BIT(1)
 #define WDT_CLEAR_TIMEOUT_STATUS       0x14
 #define   WDT_CLEAR_TIMEOUT_AND_BOOT_CODE_SELECTION    BIT(0)
@@ -160,6 +177,26 @@ static int aspeed_wdt_set_timeout(struct watchdog_device *wdd,
        return 0;
 }
 
+static int aspeed_wdt_set_pretimeout(struct watchdog_device *wdd,
+                                    unsigned int pretimeout)
+{
+       struct aspeed_wdt *wdt = to_aspeed_wdt(wdd);
+       u32 actual = pretimeout * WDT_RATE_1MHZ;
+       u32 s = wdt->cfg->irq_shift;
+       u32 m = wdt->cfg->irq_mask;
+
+       wdd->pretimeout = pretimeout;
+       wdt->ctrl &= ~m;
+       if (pretimeout)
+               wdt->ctrl |= ((actual << s) & m) | WDT_CTRL_WDT_INTR;
+       else
+               wdt->ctrl &= ~WDT_CTRL_WDT_INTR;
+
+       writel(wdt->ctrl, wdt->base + WDT_CTRL);
+
+       return 0;
+}
+
 static int aspeed_wdt_restart(struct watchdog_device *wdd,
                              unsigned long action, void *data)
 {
@@ -232,6 +269,7 @@ static const struct watchdog_ops aspeed_wdt_ops = {
        .stop           = aspeed_wdt_stop,
        .ping           = aspeed_wdt_ping,
        .set_timeout    = aspeed_wdt_set_timeout,
+       .set_pretimeout = aspeed_wdt_set_pretimeout,
        .restart        = aspeed_wdt_restart,
        .owner          = THIS_MODULE,
 };
@@ -243,10 +281,29 @@ static const struct watchdog_info aspeed_wdt_info = {
        .identity       = KBUILD_MODNAME,
 };
 
+static const struct watchdog_info aspeed_wdt_pretimeout_info = {
+       .options        = WDIOF_KEEPALIVEPING
+                       | WDIOF_PRETIMEOUT
+                       | WDIOF_MAGICCLOSE
+                       | WDIOF_SETTIMEOUT,
+       .identity       = KBUILD_MODNAME,
+};
+
+static irqreturn_t aspeed_wdt_irq(int irq, void *arg)
+{
+       struct watchdog_device *wdd = arg;
+       struct aspeed_wdt *wdt = to_aspeed_wdt(wdd);
+       u32 status = readl(wdt->base + WDT_TIMEOUT_STATUS);
+
+       if (status & WDT_TIMEOUT_STATUS_IRQ)
+               watchdog_notify_pretimeout(wdd);
+
+       return IRQ_HANDLED;
+}
+
 static int aspeed_wdt_probe(struct platform_device *pdev)
 {
        struct device *dev = &pdev->dev;
-       const struct aspeed_wdt_config *config;
        const struct of_device_id *ofdid;
        struct aspeed_wdt *wdt;
        struct device_node *np;
@@ -259,11 +316,33 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
        if (!wdt)
                return -ENOMEM;
 
+       np = dev->of_node;
+
+       ofdid = of_match_node(aspeed_wdt_of_table, np);
+       if (!ofdid)
+               return -EINVAL;
+       wdt->cfg = ofdid->data;
+
        wdt->base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(wdt->base))
                return PTR_ERR(wdt->base);
 
        wdt->wdd.info = &aspeed_wdt_info;
+
+       if (wdt->cfg->irq_mask) {
+               int irq = platform_get_irq_optional(pdev, 0);
+
+               if (irq > 0) {
+                       ret = devm_request_irq(dev, irq, aspeed_wdt_irq,
+                                              IRQF_SHARED, dev_name(dev),
+                                              wdt);
+                       if (ret)
+                               return ret;
+
+                       wdt->wdd.info = &aspeed_wdt_pretimeout_info;
+               }
+       }
+
        wdt->wdd.ops = &aspeed_wdt_ops;
        wdt->wdd.max_hw_heartbeat_ms = WDT_MAX_TIMEOUT_MS;
        wdt->wdd.parent = dev;
@@ -273,13 +352,6 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
 
        watchdog_set_nowayout(&wdt->wdd, nowayout);
 
-       np = dev->of_node;
-
-       ofdid = of_match_node(aspeed_wdt_of_table, np);
-       if (!ofdid)
-               return -EINVAL;
-       config = ofdid->data;
-
        /*
         * On clock rates:
         *  - ast2400 wdt can run at PCLK, or 1MHz
@@ -331,7 +403,7 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
                (of_device_is_compatible(np, "aspeed,ast2600-wdt"))) {
                u32 reg = readl(wdt->base + WDT_RESET_WIDTH);
 
-               reg &= config->ext_pulse_width_mask;
+               reg &= wdt->cfg->ext_pulse_width_mask;
                if (of_property_read_bool(np, "aspeed,ext-active-high"))
                        reg |= WDT_ACTIVE_HIGH_MAGIC;
                else
@@ -339,7 +411,7 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
 
                writel(reg, wdt->base + WDT_RESET_WIDTH);
 
-               reg &= config->ext_pulse_width_mask;
+               reg &= wdt->cfg->ext_pulse_width_mask;
                if (of_property_read_bool(np, "aspeed,ext-push-pull"))
                        reg |= WDT_PUSH_PULL_MAGIC;
                else
@@ -349,7 +421,7 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
        }
 
        if (!of_property_read_u32(np, "aspeed,ext-pulse-duration", &duration)) {
-               u32 max_duration = config->ext_pulse_width_mask + 1;
+               u32 max_duration = wdt->cfg->ext_pulse_width_mask + 1;
 
                if (duration == 0 || duration > max_duration) {
                        dev_err(dev, "Invalid pulse duration: %uus\n",