[M2351] Add missing delay in lp_ticker

targets/TARGET_NUVOTON/TARGET_M2351/lp_ticker.c

@@ -72,6 +72,9 @@ static int ticker_inited = 0;
 #define TMR_CMP_MIN         2
 #define TMR_CMP_MAX         0xFFFFFFu
 
+/* NOTE: When system clock is higher than timer clock, we need to add 3 engine clock
+ *       (recommended by designer) delay to wait for above timer control to take effect. */
+
 void lp_ticker_init(void)
 {
     if (ticker_inited) {
@@ -109,7 +112,10 @@ void lp_ticker_init(void)
     // Continuous mode
     // NOTE: TIMER_CTL_CNTDATEN_Msk exists in NUC472, but not in M451/M480/M2351. In M451/M480/M2351, TIMER_CNT is updated continuously by default.
     timer_base->CTL = TIMER_CONTINUOUS_MODE | prescale_timer/* | TIMER_CTL_CNTDATEN_Msk*/;
+    wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
+
     timer_base->CMP = cmp_timer;
+    wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
 
     // Set vector
     NVIC_SetVector(TIMER_MODINIT.irq_n, (uint32_t) TIMER_MODINIT.var);
@@ -117,20 +123,15 @@ void lp_ticker_init(void)
     NVIC_EnableIRQ(TIMER_MODINIT.irq_n);
 
     TIMER_EnableInt(timer_base);
+    wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
+
     TIMER_EnableWakeup(timer_base);
-
-    /* NOTE: When system clock is higher than timer clock, we need to add 3 engine clock
-     *       (recommended by designer) delay to wait for above timer control to take effect. */
-
-    /* Add delay to wait for above timer control to take effect before enabling timer counting */
     wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
+
     TIMER_Start(timer_base);
-
-    /* Add delay to wait for timer to start counting and raise active flag
-     * 
-     * It is possible timer active bit cannot be set in time while we check it, and the while loop
-     * below would return immediately. */
     wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
+
+    /* Wait for timer to start counting and raise active flag */
     while(! (timer_base->CTL & TIMER_CTL_ACTSTS_Msk));
 }
 
@@ -161,17 +162,21 @@ void lp_ticker_set_interrupt(timestamp_t timestamp)
      *       (TMR_CMP_MIN - interval_clk) clocks when interval_clk is between [1, TMR_CMP_MIN). */
     uint32_t cmp_timer = timestamp * NU_TMRCLK_PER_TICK;
     cmp_timer = NU_CLAMP(cmp_timer, TMR_CMP_MIN, TMR_CMP_MAX);
+
     timer_base->CMP = cmp_timer;
+    wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
 }
 
 void lp_ticker_disable_interrupt(void)
 {
     TIMER_DisableInt((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
+    wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
 }
 
 void lp_ticker_clear_interrupt(void)
 {
     TIMER_ClearIntFlag((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
+    wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
 }
 
 void lp_ticker_fire_interrupt(void)
@@ -197,8 +202,11 @@ static void tmr3_vec(void)
 #endif
 {
     TIMER_ClearIntFlag((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
+    wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
+
     TIMER_ClearWakeupFlag((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
-    
+    wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
+
     // NOTE: lp_ticker_set_interrupt() may get called in lp_ticker_irq_handler();
     lp_ticker_irq_handler();
 }

targets/TARGET_NUVOTON/TARGET_M2351/us_ticker.c

@@ -111,6 +111,7 @@ void us_ticker_init(void)
     TIMER_EnableInt(timer_base);
 
     TIMER_Start(timer_base);
+    /* Wait for timer to start counting and raise active flag */
     while(! (timer_base->CTL & TIMER_CTL_ACTSTS_Msk));
 }