esp_eth: Improve GPIO interrupt processing in w5500 driver

Increase the interrupt reassert level timing so the chances of missing
two consecutive events are minimal.
Enable only SIR_RECV interrupt event, so the SEND events are not used
for GPIO signal.

components/esp_eth/src/esp_eth_mac_w5500.c

@@ -259,9 +259,12 @@ static esp_err_t w5500_setup_default(emac_w5500_t *emac)
     /* Enable MAC RAW mode for SOCK0, enable MAC filter, no blocking broadcast and multicast */
     reg_value = W5500_SMR_MAC_RAW | W5500_SMR_MAC_FILTER;
     ESP_GOTO_ON_ERROR(w5500_write(emac, W5500_REG_SOCK_MR(0), &reg_value, sizeof(reg_value)), err, TAG, "write SMR failed");
-    /* Enable receive and send event for SOCK0 */
-    reg_value = W5500_SIR_RECV | W5500_SIR_SEND;
+    /* Enable receive event for SOCK0 */
+    reg_value = W5500_SIR_RECV;
     ESP_GOTO_ON_ERROR(w5500_write(emac, W5500_REG_SOCK_IMR(0), &reg_value, sizeof(reg_value)), err, TAG, "write SOCK0 IMR failed");
+    /* Set the interrupt re-assert level to maximum (~1.5ms) to lower the chances of missing it */
+    uint16_t int_level = __builtin_bswap16(0xFFFF);
+    ESP_GOTO_ON_ERROR(w5500_write(emac, W5500_REG_INTLEVEL, &int_level, sizeof(int_level)), err, TAG, "write INTLEVEL failed");
 
 err:
     return ret;

components/esp_eth/src/w5500.h

@@ -33,6 +33,7 @@
 
 #define W5500_REG_MR        W5500_MAKE_MAP(0x0000, W5500_BSB_COM_REG) // Mode
 #define W5500_REG_MAC       W5500_MAKE_MAP(0x0009, W5500_BSB_COM_REG) // MAC Address
+#define W5500_REG_INTLEVEL  W5500_MAKE_MAP(0x0013, W5500_BSB_COM_REG) // Interrupt Level Timeout
 #define W5500_REG_IR        W5500_MAKE_MAP(0x0015, W5500_BSB_COM_REG) // Interrupt
 #define W5500_REG_IMR       W5500_MAKE_MAP(0x0016, W5500_BSB_COM_REG) // Interrupt Mask
 #define W5500_REG_SIR       W5500_MAKE_MAP(0x0017, W5500_BSB_COM_REG) // Socket Interrupt