From: Lisa Hsu <hsul@eecs.umich.edu>
Date: Wed, 30 Jun 2004 04:50:56 +0000 (-0400)
Subject: fix transmit side checksum offloading to not generate a pseudo header.
X-Git-Tag: m5_1.0_tutorial~282^2
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=167c57f265592e8baa3fc4809e256646efdf32df;p=gem5.git

fix transmit side checksum offloading to not generate a pseudo header.

dev/ns_gige.cc:
    transmit side checksum offloading doesn't need pseudo header generation, it just takes the pseudo header checksum and uses it.

--HG--
extra : convert_revision : 9741bd650415c18ed37b06a453b23610d028135b
---

diff --git a/dev/ns_gige.cc b/dev/ns_gige.cc
index f3f2f10b3..64f255e6b 100644
--- a/dev/ns_gige.cc
+++ b/dev/ns_gige.cc
@@ -1780,7 +1780,8 @@ NSGigE::txKick()
                         udpChecksum(txPacket, true);
                     } else if (txDescCache.extsts & EXTSTS_TCPPKT) {
                         tcpChecksum(txPacket, true);
-                    } else if (txDescCache.extsts & EXTSTS_IPPKT) {
+                    }
+                    if (txDescCache.extsts & EXTSTS_IPPKT) {
                         ipChecksum(txPacket, true);
                     }
                 }
@@ -2043,15 +2044,25 @@ NSGigE::tcpChecksum(PacketPtr packet, bool gen)
     ip_header *ip = packet->getIpHdr();
     tcp_header *hdr = packet->getTcpHdr(ip);
 
+    uint16_t cksum;
     pseudo_header *pseudo = new pseudo_header;
+    if (!gen) {
+        pseudo->src_ip_addr = ip->src_ip_addr;
+        pseudo->dest_ip_addr = ip->dest_ip_addr;
+        pseudo->protocol = reverseEnd16(ip->protocol);
+        pseudo->len = reverseEnd16(reverseEnd16(ip->dgram_len) - (ip->vers_len & 0xf)*4);
 
-    pseudo->src_ip_addr = ip->src_ip_addr;
-    pseudo->dest_ip_addr = ip->dest_ip_addr;
-    pseudo->protocol = reverseEnd16(ip->protocol);
-    pseudo->len = reverseEnd16(reverseEnd16(ip->dgram_len) - (ip->vers_len & 0xf)*4);
-
-    uint16_t cksum = checksumCalc((uint16_t *) pseudo, (uint16_t *) hdr,
+        cksum = checksumCalc((uint16_t *) pseudo, (uint16_t *) hdr,
                                   (uint32_t) reverseEnd16(pseudo->len));
+    } else {
+        pseudo->src_ip_addr = 0;
+        pseudo->dest_ip_addr = 0;
+        pseudo->protocol = hdr->chksum;
+        pseudo->len = 0;
+        hdr->chksum = 0;
+        cksum = checksumCalc((uint16_t *) pseudo, (uint16_t *) hdr,
+                             (uint32_t) (reverseEnd16(ip->dgram_len) - (ip->vers_len & 0xf)*4));
+    }
 
     delete pseudo;
     if (gen)
@@ -2071,7 +2082,7 @@ NSGigE::ipChecksum(PacketPtr packet, bool gen)
     uint16_t cksum = checksumCalc(NULL, (uint16_t *) hdr, (hdr->vers_len & 0xf)*4);
 
     if (gen) {
-        DPRINTF(Ethernet, "generated checksum: %#x\n", cksum);
+        DPRINTF(EthernetCksum, "generated checksum: %#x\n", cksum);
         hdr->hdr_chksum = cksum;
     }
     else