Merge branch 'optimization/lwip_dhcp_coarse_timer_4.4' into 'release/…

…v4.4'

lwip:optimization dhcp coarse timer for 4.4

See merge request espressif/esp-idf!22425

components/lwip/Kconfig

@@ -283,6 +283,14 @@ menu "LWIP"
             options and values. If your code meets LWIP_ASSERT due to option value is too long.
             Please increase the LWIP_DHCP_OPTIONS_LEN value.
 
+    config LWIP_DHCP_COARSE_TIMER_SECS
+        int "DHCP coarse timer interval(s)"
+        default 1
+        range 1 10
+        help
+            Set DHCP coarse interval in seconds.
+            A higher value will be less precise but cost less power consumption.
+
     menu "DHCP server"
 
         config LWIP_DHCPS

components/lwip/port/esp32/include/lwipopts.h

@@ -21,6 +21,11 @@
 #include "netif/dhcp_state.h"
 #include "sntp/sntp_get_set_time.h"
 
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
 /* Enable all Espressif-only options */
 
 /*
@@ -231,6 +236,33 @@
  */
 #define ESP_DHCP_DISABLE_CLIENT_ID      CONFIG_LWIP_DHCP_DISABLE_CLIENT_ID
 
+#define DHCP_DEFINE_CUSTOM_TIMEOUTS     1
+/* Since for embedded devices it's not that hard to miss a discover packet, so lower
+ * the discover retry backoff time from (2,4,8,16,32,60,60)s to (500m,1,2,4,8,15,15)s.
+ */
+ #define DHCP_REQUEST_TIMEOUT_SEQUENCE(state, tries)   (state == DHCP_STATE_REQUESTING ? \
+                                                       (uint16_t)(1 * 1000) : \
+                                                       (uint16_t)(((tries) < 6 ? 1 << (tries) : 60) * 250))
+
+#define DHCP_COARSE_TIMER_SECS CONFIG_LWIP_DHCP_COARSE_TIMER_SECS
+
+static inline uint32_t timeout_from_offered(uint32_t lease, uint32_t min)
+{
+    uint32_t timeout = lease;
+    if (timeout == 0) {
+      timeout = min;
+    }
+    timeout = (timeout + DHCP_COARSE_TIMER_SECS - 1) / DHCP_COARSE_TIMER_SECS;
+    return timeout;
+}
+
+#define DHCP_CALC_TIMEOUT_FROM_OFFERED_T0_LEASE(dhcp) \
+   timeout_from_offered((dhcp)->offered_t0_lease, 120)
+#define DHCP_CALC_TIMEOUT_FROM_OFFERED_T1_RENEW(dhcp) \
+   timeout_from_offered((dhcp)->offered_t1_renew, (dhcp)->t0_timeout >> 1 /* 50% */)
+#define DHCP_CALC_TIMEOUT_FROM_OFFERED_T2_REBIND(dhcp) \
+   timeout_from_offered((dhcp)->offered_t2_rebind, ((dhcp)->t0_timeout / 8) * 7 /* 87.5% */)
+
 /**
  * CONFIG_LWIP_DHCP_RESTORE_LAST_IP==1: Last valid IP address obtained from DHCP server
  * is restored after reset/power-up.
@@ -1111,4 +1143,8 @@
 
 #define SOC_SEND_LOG //printf
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* __LWIPOPTS_H__ */