From c172cc8dbea177b90430f3e106d364a98356ca3b Mon Sep 17 00:00:00 2001
From: OBattler <oubattler@gmail.com>
Date: Sun, 29 Sep 2024 10:27:21 +0200
Subject: [PATCH] RTL8139C+: Fix duplex negotiation so it correctly negotiates
 full duples, fixes #4867.

---
 src/network/net_rtl8139.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/network/net_rtl8139.c b/src/network/net_rtl8139.c
index 0b00d589a..f04f9b7a3 100644
--- a/src/network/net_rtl8139.c
+++ b/src/network/net_rtl8139.c
@@ -1076,10 +1076,11 @@ rtl8139_reset(void *priv)
     s->cplus_enabled = 0;
 
 #if 0
-    s->BasicModeCtrl = 0x3100; // 100Mbps, full duplex, autonegotiation
     s->BasicModeCtrl = 0x2100; // 100Mbps, full duplex
-#endif
+    s->BasicModeCtrl = 0x3100; // 100Mbps, full duplex, autonegotiation
     s->BasicModeCtrl = 0x1000; // autonegotiation
+#endif
+    s->BasicModeCtrl = 0x1100; // full duplex, autonegotiation
 
     rtl8139_reset_phy(s);