Fixed issue related to Zephyr. QEMU issue #66.

This patches makes counter only appear to reset after the timer
interrupt gets to be served.
Also removed the condition that would make timers less reactive.

target/arc/timer.c

@@ -67,17 +67,6 @@ static void cpu_arc_timer_update(CPUARCState *env, uint32_t timer)
 
     delta = env->timer[timer].T_Limit - t_count;
 
-    /*
-     * Artificially limit timeout rate to something achievable under
-     * QEMU. Otherwise, QEMU spends all its time generating timer
-     * interrupts, and there is no forward progress. About ten
-     * microseconds is the fastest that really works on the current
-     * generation of host machines.
-     */
-    if (delta < TIMEOUT_LIMIT) {
-        delta = TIMEOUT_LIMIT;
-    }
-
 #ifndef CONFIG_USER_ONLY
     timer_mod_ns(env->cpu_timer[timer], now + CYCLES_TO_NS((uint64_t)delta));
 #endif
@@ -235,6 +224,9 @@ static void cpu_arc_count_reset(CPUARCState *env, uint32_t timer)
 static uint32_t cpu_arc_count_get(CPUARCState *env, uint32_t timer)
 {
     uint32_t count = T_COUNT(timer);
+    if((env->timer[timer].T_Cntrl & TMR_IP) != 0) {
+      count = env->timer[timer].T_Limit;
+    }
     qemu_log_mask(LOG_UNIMP, "[TMR%d] Timer count %d.\n", timer, count);
     return count;
 }
@@ -273,6 +265,7 @@ static void cpu_arc_store_limit(CPUARCState *env,
         break;
     }
     env->timer[timer].T_Limit = value;
+    qemu_log_mask(LOG_UNIMP, "[TMR%d] Set Timer limit "TARGET_FMT_ld".\n", timer, env->timer[timer].T_Limit);
     cpu_arc_timer_update(env, timer);
 }