From d9af44ecef79aadd04070e76e19ca56f3e4673e2 Mon Sep 17 00:00:00 2001
From: sthen <sthen@openbsd.org>
Date: Mon, 13 Apr 2015 20:45:49 +0000
Subject: [PATCH] Initialize RX/TX on re(4) slightly later; it appears that
 newer chips don't setup DMA correctly until more configuration has been done
 - enabling RX too soon causes DMA to bad places. KVM corruption problems
 reported by Adam Wolk on Lenovo G50-70 (RTL8111GU).

Diff derived by Brad from FreeBSD commit; see bz# 197535 and 193743, inspired by
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=d6e572911a4cb2b9fcd1c26a38d5317a3971f2fd

Tested on the following by Brad, Adam Wolk, box963 at gmail, Jim Smith

re0 at pci4 dev 0 function 0 "Realtek 8168" rev 0x03: RTL8168D/8111D (0x2800), apic 2 int 16, address 00:0a:cd:1a:86:04
re0 at pci2 dev 0 function 0 "Realtek 8168" rev 0x0c: RTL8168G/8111G (0x4c00), msi, address 80:ee:73:76:8e:8a
re0 at pci0 dev 3 function 0 "Realtek 8169" rev 0x10: RTL8110S (0x0400), ivec 0x78c, address 00:22:3f:ee:fa:25
re0 at pci1 dev 0 function 0 "Realtek 8168" rev 0x06: RTL8168E/8111E (0x2c00), msi, address 00:0d:b9:31:2e:88
re0 at pci1 dev 0 function 0 "Realtek 8168" rev 0x10: RTL8168GU/8111GU (0x5080), msi, address 68:f7:28:18:35:8e

ok mpi@ dlg@
---
 sys/dev/ic/re.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/sys/dev/ic/re.c b/sys/dev/ic/re.c
index a23e61502fc..c7099caa114 100644
--- a/sys/dev/ic/re.c
+++ b/sys/dev/ic/re.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: re.c,v 1.177 2015/03/20 12:04:09 dlg Exp $	*/
+/*	$OpenBSD: re.c,v 1.178 2015/04/13 20:45:49 sthen Exp $	*/
 /*	$FreeBSD: if_re.c,v 1.31 2004/09/04 07:54:05 ru Exp $	*/
 /*
  * Copyright (c) 1997, 1998-2003
@@ -1980,11 +1980,6 @@ re_init(struct ifnet *ifp)
 		CSR_WRITE_4(sc, RL_MISC, CSR_READ_4(sc, RL_MISC) &
 		    ~0x00080000);
 
-	/*
-	 * Enable transmit and receive.
-	 */
-	CSR_WRITE_1(sc, RL_COMMAND, RL_CMD_TX_ENB|RL_CMD_RX_ENB);
-
 	/*
 	 * Set the initial TX and RX configuration.
 	 */
@@ -1999,6 +1994,11 @@ re_init(struct ifnet *ifp)
 		rxcfg |= RL_RXCFG_EARLYOFFV2;
 	CSR_WRITE_4(sc, RL_RXCFG, rxcfg);
 
+	/*
+	 * Enable transmit and receive.
+	 */
+	CSR_WRITE_1(sc, RL_COMMAND, RL_CMD_TX_ENB | RL_CMD_RX_ENB);
+
 	/* Program promiscuous mode and multicast filters. */
 	re_iff(sc);
 
@@ -2010,10 +2010,6 @@ re_init(struct ifnet *ifp)
 
 	/* Start RX/TX process. */
 	CSR_WRITE_4(sc, RL_MISSEDPKT, 0);
-#ifdef notdef
-	/* Enable receiver and transmitter. */
-	CSR_WRITE_1(sc, RL_COMMAND, RL_CMD_TX_ENB|RL_CMD_RX_ENB);
-#endif
 
 	/*
 	 * For 8169 gigE NICs, set the max allowed RX packet
-- 
2.20.1