From c5768c019e7201393aefd67777f10ea0131d18a6 Mon Sep 17 00:00:00 2001
From: yuanjm <yuanjianmin@espressif.com>
Date: Mon, 8 Jun 2020 14:26:46 +0800
Subject: [PATCH] feat(lwip): make LWIP TCP rto time configurable

---
 components/lwip/Kconfig                       | 7 +++++++
 components/lwip/lwip                          | 2 +-
 components/lwip/port/esp32/include/lwipopts.h | 6 ++++++
 3 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/components/lwip/Kconfig b/components/lwip/Kconfig
index dfc2b714d..6e3e75399 100644
--- a/components/lwip/Kconfig
+++ b/components/lwip/Kconfig
@@ -497,6 +497,13 @@ menu "LWIP"
             help
                 Enable this feature to support TCP window scaling.
 
+        config LWIP_TCP_RTO_TIME
+            int "Default TCP rto time"
+            default 3000
+            help
+                Set default TCP rto time for a reasonable initial rto.
+                In bad network environment, recommend set value of rto time to 1500.
+
     endmenu # TCP
 
     menu "UDP"
diff --git a/components/lwip/lwip b/components/lwip/lwip
index 50e4e0d18..64b640eca 160000
--- a/components/lwip/lwip
+++ b/components/lwip/lwip
@@ -1 +1 @@
-Subproject commit 50e4e0d1821a6e5deab0ead9f35ffb4e60625ea6
+Subproject commit 64b640ecae5a6ce510814944d75e9ff408d3fc8d
diff --git a/components/lwip/port/esp32/include/lwipopts.h b/components/lwip/port/esp32/include/lwipopts.h
index 978857d6a..b41346d9a 100644
--- a/components/lwip/port/esp32/include/lwipopts.h
+++ b/components/lwip/port/esp32/include/lwipopts.h
@@ -400,6 +400,12 @@
 #define TCP_RCV_SCALE                   CONFIG_LWIP_TCP_RCV_SCALE
 #endif
 
+/**
+ * LWIP_TCP_RTO_TIME: TCP rto time.
+ * Default is 3 second.
+ */
+#define LWIP_TCP_RTO_TIME             CONFIG_LWIP_TCP_RTO_TIME
+
 /*
    ----------------------------------
    ---------- Pbuf options ----------