pcnet: Properly handle TX requests during Link Fail

As long as we have no link and we aren't in internal loopback mode, no
packet must be sent. Instead, LCAR needs to be set in any active TX
descriptor and also CERR in CSR0.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>

diff --git a/hw/pcnet.c b/hw/pcnet.c
index 741340933191777355f443a2a06a834fdf9eba08..d769b08b781266250081713e063c079ef0ec0073 100644 (file)
--- a/hw/pcnet.c
+++ b/hw/pcnet.c
@@ -77,6 +77,7 @@ struct qemu_ether_header {
 #define CSR_DTX(S)       !!(((S)->csr[15])&0x0002)
 #define CSR_LOOP(S)      !!(((S)->csr[15])&0x0004)
 #define CSR_DXMTFCS(S)   !!(((S)->csr[15])&0x0008)
+#define CSR_INTL(S)      !!(((S)->csr[15])&0x0040)
 #define CSR_DRCVPA(S)    !!(((S)->csr[15])&0x2000)
 #define CSR_DRCVBC(S)    !!(((S)->csr[15])&0x4000)
 #define CSR_PROM(S)      !!(((S)->csr[15])&0x8000)
@@ -1234,6 +1235,15 @@ static void pcnet_transmit(PCNetState *s)
             if (BCR_SWSTYLE(s) != 1)
                 add_crc = GET_FIELD(tmd.status, TMDS, ADDFCS);
         }
+        if (s->lnkst == 0 &&
+            (!CSR_LOOP(s) || (!CSR_INTL(s) && !BCR_TMAULOOP(s)))) {
+            SET_FIELD(&tmd.misc, TMDM, LCAR, 1);
+            SET_FIELD(&tmd.status, TMDS, ERR, 1);
+            SET_FIELD(&tmd.status, TMDS, OWN, 0);
+            s->csr[0] |= 0xa000; /* ERR | CERR */
+            s->xmit_pos = -1;
+            goto txdone;
+        }
         if (!GET_FIELD(tmd.status, TMDS, ENP)) {
             int bcnt = 4096 - GET_FIELD(tmd.length, TMDL, BCNT);
             s->phys_mem_read(s->dma_opaque, PHYSADDR(s, tmd.tbadr),
@@ -1262,6 +1272,7 @@ static void pcnet_transmit(PCNetState *s)
             s->xmit_pos = -1;
         }
 
+    txdone:
         SET_FIELD(&tmd.status, TMDS, OWN, 0);
         TMDSTORE(&tmd, PHYSADDR(s,CSR_CXDA(s)));
         if (!CSR_TOKINTD(s) || (CSR_LTINTEN(s) && GET_FIELD(tmd.status, TMDS, LTINT)))

diff --git a/hw/pcnet.h b/hw/pcnet.h
index edc81c90ac928c52fd40bebbfe8ec721d861728a..803a2cc1ec256ac9cd383f798b3fbc911f662ca2 100644 (file)
--- a/hw/pcnet.h
+++ b/hw/pcnet.h
@@ -20,6 +20,7 @@
 #define BCR_SWS      20
 #define BCR_PLAT     22
 
+#define BCR_TMAULOOP(S)  !!((S)->bcr[BCR_MC  ] & 0x4000)
 #define BCR_APROMWE(S)   !!((S)->bcr[BCR_MC  ] & 0x0100)
 #define BCR_DWIO(S)      !!((S)->bcr[BCR_BSBC] & 0x0080)
 #define BCR_SSIZE32(S)   !!((S)->bcr[BCR_SWS ] & 0x0100)