drivers: watchdog: wdog32: add delay before init
WDOG32 requires at least 2.5 periods of wdog clock after start up or
before reconfig.
Signed-off-by: Yves Wang <zhengjia.wang@nxp.com>
diff --git a/drivers/watchdog/wdt_mcux_wdog32.c b/drivers/watchdog/wdt_mcux_wdog32.c
index 54bbe63..2f142a0 100644
--- a/drivers/watchdog/wdt_mcux_wdog32.c
+++ b/drivers/watchdog/wdt_mcux_wdog32.c
@@ -50,10 +50,25 @@
return (WDOG_Type *)DEVICE_MMIO_NAMED_GET(dev, reg);
}
+/* When system is boot up, WDOG32 is disabled. app 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.
+ */
+#define WDOG32_CONFIG_WAIT(clock_hz, divider) \
+ do { \
+ uint64_t _num = 5ULL * 1000ULL * (uint64_t)divider; \
+ uint64_t _den = 2UL * (uint64_t)clock_hz; \
+ uint32_t ms = (uint32_t)((_num + _den - 1ULL) / _den); \
+ k_msleep(ms ? ms : 1u); \
+ } while (0)
+
static int mcux_wdog32_setup(const struct device *dev, uint8_t options)
{
+ const struct mcux_wdog32_config *config = dev->config;
struct mcux_wdog32_data *data = dev->data;
WDOG_Type *base = get_base_address(dev);
+ uint32_t clock_freq;
+ int divider;
if (!data->timeout_valid) {
LOG_ERR("No valid timeouts installed");
@@ -64,6 +79,20 @@
data->wdog_config.workMode.enableDebug = (options & WDT_OPT_PAUSE_HALTED_BY_DBG) == 0U;
+#if DT_NODE_HAS_PROP(DT_INST_PHANDLE(0, clocks), clock_frequency)
+ clock_freq = config->clock_frequency;
+#else /* !DT_NODE_HAS_PROP(DT_INST_PHANDLE(0, clocks), clock_frequency) */
+ if (!device_is_ready(config->clock_dev)) {
+ LOG_ERR("clock control device not ready");
+ return -ENODEV;
+ }
+
+ if (clock_control_get_rate(config->clock_dev, config->clock_subsys, &clock_freq)) {
+ return -EINVAL;
+ }
+#endif /* !DT_NODE_HAS_PROP(DT_INST_PHANDLE(0, clocks), clock_frequency) */
+ divider = config->clk_divider == kWDOG32_ClockPrescalerDivide1 ? 1U : 256U;
+ WDOG32_CONFIG_WAIT(clock_freq, divider);
WDOG32_Init(base, &data->wdog_config);
LOG_DBG("Setup the watchdog");
