Padding more bytes than necessary one broke another variants of

PCIe RealTek chips. Only pad IP packets if the payload is less than
28 bytes.

Obtained from:	NetBSD
PR:		kern/122221

1 files changed, 6 insertions, 0 deletions

diff --git a/sys/pci/if_rlreg.h b/sys/pci/if_rlreg.h
index 7e86689..5038666 100644
--- a/sys/pci/if_rlreg.h
+++ b/sys/pci/if_rlreg.h
@@ -497,6 +497,12 @@
 
 #define RL_ETHER_ALIGN	2
 
+/*
+ * re(4) hardware ip4csum-tx could be mangled with 28 bytes or less IP packets.
+ */
+#define	RL_IP4CSUMTX_MINLEN	28
+#define	RL_IP4CSUMTX_PADLEN	(ETHER_HDR_LEN + RL_IP4CSUMTX_MINLEN)
+
 struct rl_chain_data {
 	uint16_t		cur_rx;
 	uint8_t			*rl_rx_buf;