Skip net_poll and timers unless their interrupt has fired

firmware/include/timer_queue.h

@@ -15,6 +15,7 @@ inline bool operator<(const timer_entry& a, const timer_entry& b) {
 struct timer_queue {
     sorted_list<timer_entry, 16> queue;
     alarm_id_t alarm = -1;
+    volatile bool irq_pending = false;
 
     void schedule(absolute_time_t when, std::function<void()> fn) {
         queue.insert({when, std::move(fn)});
@@ -26,6 +27,8 @@ struct timer_queue {
     }
 
     void run() {
+        if (!irq_pending) return;
+        irq_pending = false;
         while (!queue.empty()) {
             auto& front = queue.front();
             if (absolute_time_diff_us(get_absolute_time(), front.when) > 0) break;
@@ -39,12 +42,15 @@ struct timer_queue {
     bool empty() const { return queue.empty(); }
 
 private:
-    static int64_t alarm_cb(alarm_id_t, void*) { return 0; }
+    static int64_t alarm_cb(alarm_id_t, void* user_data) {
+        static_cast<timer_queue*>(user_data)->irq_pending = true;
+        return 0;
+    }
 
     void arm() {
         if (alarm >= 0) cancel_alarm(alarm);
         alarm = -1;
         if (!queue.empty())
-            alarm = add_alarm_at(queue.front().when, alarm_cb, nullptr, false);
+            alarm = add_alarm_at(queue.front().when, alarm_cb, this, false);
     }
 };

firmware/lib/net.cpp

@@ -293,6 +293,8 @@ void net_set_handler(net_handler handler) {
 }
 
 void net_poll() {
+    if (!w6300::irq_pending) return;
+    w6300::irq_pending = false;
     w6300::clear_interrupt(w6300::ik_int_all);
     if (w6300::get_socket_recv_buf(raw_socket) == 0) return;
     static uint8_t rx_buf[1518];

firmware/w6300/w6300.cpp

@@ -78,7 +78,7 @@ void pio_init() {
     gpio_set_dir(PIN_INT, GPIO_IN);
     gpio_pull_up(PIN_INT);
     gpio_set_irq_enabled_with_callback(PIN_INT, GPIO_IRQ_EDGE_FALL, true,
-        [](uint, uint32_t){});
+        [](uint, uint32_t){ irq_pending = true; });
 
     pio_hw_t *pios[2] = {pio0, pio1};
     uint pio_index = 1;
@@ -490,6 +490,8 @@ std::expected<void, sock_error> close(socket_id sid) {
 
 } // namespace
 
+volatile bool irq_pending = false;
+
 void clear_interrupt(intr_kind intr) {
     set_irclr((uint8_t)intr);
     uint8_t sir = (uint8_t)((uint16_t)intr >> 8);

firmware/w6300/w6300.h

@@ -37,6 +37,8 @@ void reset();
 void init();
 bool check();
 
+extern volatile bool irq_pending;
+
 void clear_interrupt(intr_kind intr);
 void set_interrupt_mask(intr_kind intr);