From 1b0009dbd41e68ca2b19bc7a20dc5499c31938cd Mon Sep 17 00:00:00 2001
From: balrog <balrog@c046a42c-6fe2-441c-8c8c-71466251a162>
Date: Wed, 16 Jul 2008 12:39:45 +0000
Subject: [PATCH] e1000: only use TSE if enabled for current packet (Anthony
 Xu).

Previously, all data descriptors used TSE context descriptor by default,
It's not correct, per spec, data descriptor uses TSE bit to indicate
whether use TSE,
Legacy data descripter never use TSE.
This patch fixed this bug.


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4878 c046a42c-6fe2-441c-8c8c-71466251a162
---
 hw/e1000.c | 51 ++++++++++++++++++++++++++++++++-------------------
 1 file changed, 32 insertions(+), 19 deletions(-)

diff --git a/hw/e1000.c b/hw/e1000.c
index c45020f4..47e20c14 100644
--- a/hw/e1000.c
+++ b/hw/e1000.c
@@ -105,6 +105,7 @@ typedef struct E1000State_st {
         char tse;
         char ip;
         char tcp;
+        char cptse;     // current packet tse bit
     } tx;
 
     struct {
@@ -308,7 +309,7 @@ xmit_seg(E1000State *s)
     unsigned int frames = s->tx.tso_frames, css, sofar, n;
     struct e1000_tx *tp = &s->tx;
 
-    if (tp->tse) {
+    if (tp->tse && tp->cptse) {
         css = tp->ipcss;
         DBGOUT(TXSUM, "frames %d size %d ipcss %d\n",
                frames, tp->size, css);
@@ -382,37 +383,49 @@ process_tx_desc(E1000State *s, struct e1000_tx_desc *dp)
             tp->tucso = tp->tucss + (tp->tcp ? 16 : 6);
         }
         return;
-    } else if (dtype == (E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D))
+    } else if (dtype == (E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D)) {
+        // data descriptor
         tp->sum_needed = le32_to_cpu(dp->upper.data) >> 8;
+        tp->cptse = ( txd_lower & E1000_TXD_CMD_TSE ) ? 1 : 0;
+    } else
+        // legacy descriptor
+        tp->cptse = 0;
 
     addr = le64_to_cpu(dp->buffer_addr);
-    if (tp->tse) {
+    if (tp->tse && tp->cptse) {
         hdr = tp->hdr_len;
         msh = hdr + tp->mss;
+        do {
+            bytes = split_size;
+            if (tp->size + bytes > msh)
+                bytes = msh - tp->size;
+            cpu_physical_memory_read(addr, tp->data + tp->size, bytes);
+            if ((sz = tp->size + bytes) >= hdr && tp->size < hdr)
+                memmove(tp->header, tp->data, hdr);
+            tp->size = sz;
+            addr += bytes;
+            if (sz == msh) {
+                xmit_seg(s);
+                memmove(tp->data, tp->header, hdr);
+                tp->size = hdr;
+            }
+        } while (split_size -= bytes);
+    } else if (!tp->tse && tp->cptse) {
+        // context descriptor TSE is not set, while data descriptor TSE is set
+        DBGOUT(TXERR, "TCP segmentaion Error\n");
+    } else {
+        cpu_physical_memory_read(addr, tp->data + tp->size, split_size);
+        tp->size += split_size;
     }
-    do {
-        bytes = split_size;
-        if (tp->size + bytes > msh)
-            bytes = msh - tp->size;
-        cpu_physical_memory_read(addr, tp->data + tp->size, bytes);
-        if ((sz = tp->size + bytes) >= hdr && tp->size < hdr)
-            memmove(tp->header, tp->data, hdr);
-        tp->size = sz;
-        addr += bytes;
-        if (sz == msh) {
-            xmit_seg(s);
-            memmove(tp->data, tp->header, hdr);
-            tp->size = hdr;
-        }
-    } while (split_size -= bytes);
 
     if (!(txd_lower & E1000_TXD_CMD_EOP))
         return;
-    if (tp->size > hdr)
+    if (!(tp->tse && tp->cptse && tp->size < hdr))
         xmit_seg(s);
     tp->tso_frames = 0;
     tp->sum_needed = 0;
     tp->size = 0;
+    tp->cptse = 0;
 }
 
 static uint32_t
-- 
2.39.5