MIMXRT1050: Add Watchdog support

Signed-off-by: Mahesh Mahadevan <mahesh.mahadevan@nxp.com>

targets/TARGET_NXP/TARGET_MCUXpresso_MCUS/TARGET_IMX/watchdog_api.c

@@ -0,0 +1,90 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2020 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include "watchdog_api.h"
+
+#if DEVICE_WATCHDOG
+
+#include "reset_reason_api.h"
+#include "fsl_rtwdog.h"
+#include "fsl_clock.h"
+#include "platform/mbed_wait_api.h"
+
+// Platform specific watchdog definitions
+#define LPO_CLOCK_FREQUENCY 32768
+#define MAX_TIMEOUT         0xFFFFUL
+#define DELAY_TIME          100000U
+
+// Number of decrements in the timeout register per millisecond
+#define TICKS_PER_MS ((LPO_CLOCK_FREQUENCY) / 1000)
+
+// Maximum timeout that can be specified in milliseconds
+#define MAX_TIMEOUT_MS ((MAX_TIMEOUT) / (TICKS_PER_MS))
+
+watchdog_status_t hal_watchdog_init(const watchdog_config_t *config)
+{
+    uint32_t temp;
+    rtwdog_config_t cfg;
+
+    /* When system is boot up, WDOG32 is disabled. We must wait for at least 2.5
+     * periods of wdog32 clock to reconfigure wodg32. So Delay a while to wait for
+     * the previous configuration taking effect. */
+    for (temp = 0; temp < DELAY_TIME; temp++) {
+        __NOP();
+    }
+
+    RTWDOG_GetDefaultConfig(&cfg);
+
+    cfg.workMode.enableStop = true;
+    cfg.workMode.enableDebug = true;
+    cfg.timeoutValue = (TICKS_PER_MS * config->timeout_ms);
+
+    RTWDOG_Init(RTWDOG, &cfg);
+
+    return WATCHDOG_STATUS_OK;
+}
+
+void hal_watchdog_kick(void)
+{
+    RTWDOG_Refresh(RTWDOG);
+}
+
+watchdog_status_t hal_watchdog_stop(void)
+{
+    RTWDOG_Deinit(RTWDOG);
+
+    return WATCHDOG_STATUS_OK;
+}
+
+uint32_t hal_watchdog_get_reload_value(void)
+{
+    const uint32_t timeout = RTWDOG->TOVAL;
+
+    return (timeout / TICKS_PER_MS);
+}
+
+watchdog_features_t hal_watchdog_get_platform_features(void)
+{
+    watchdog_features_t features;
+    features.max_timeout = MAX_TIMEOUT_MS;
+    features.update_config = true;
+    features.disable_watchdog = true;
+    features.clock_typical_frequency = 32000;
+    features.clock_max_frequency = 32768;
+
+    return features;
+}
+
+#endif // DEVICE_WATCHDOG

targets/targets.json

@@ -1943,7 +1943,8 @@
             "SPI",
             "SPISLAVE",
             "STDIO_MESSAGES",
-            "TRNG"
+            "TRNG",
+            "WATCHDOG"
         ],
         "release_versions": ["2", "5"],
         "features": ["LWIP"],