[PATCH] 2.6.x Re: Tulip 21040 hangs with ifconfig promisc

[Krzysztof Halasa <khc@xxxxxxxxx>]

Hi,

Bug (2.6.x Linux, DE21040 tulip):
> Doing "ifconfig eth0 promisc" kills the ethernet. Interrupts are gone,
> nothing in dmesg. -promisc nor ifconfig down/up doesn't fix it,
> only driver rmmod/insmod does.

The attached patch fixes the problem: de->macmode variable,
meant to shadow MacMode (CSR6) register, was used inconsistently,
causing some updates to this register to be dropped.

2.4 kernel doesn't shadow this register at all, so I removed
shadowing from 2.6 as well.
-- 
Krzysztof Halasa, B*FH

--- linux-2.6/drivers/net/tulip/de2104x.c       14 Mar 2004 17:05:37 -0000      
1.24
+++ linux-2.6/drivers/net/tulip/de2104x.c       17 Mar 2004 16:14:48 -0000
@@ -303,7 +303,6 @@
        struct net_device_stats net_stats;
 
        struct pci_dev          *pdev;
-       u32                     macmode;
 
        u16                     setup_frame[DE_SETUP_FRAME_WORDS];
 
@@ -732,7 +731,7 @@
        struct de_desc *txd;
        struct de_desc *dummy_txd = NULL;
 
-       macmode = de->macmode & ~(AcceptAllMulticast | AcceptAllPhys);
+       macmode = dr32(MacMode) & ~(AcceptAllMulticast | AcceptAllPhys);
 
        if (dev->flags & IFF_PROMISC) { /* Set promiscuous. */
                macmode |= AcceptAllMulticast | AcceptAllPhys;
@@ -805,10 +804,8 @@
        dw32(TxPoll, NormalTxPoll);
 
 out:
-       if (macmode != de->macmode) {
-               dw32 (MacMode, macmode);
-               de->macmode = macmode;
-       }
+       if (macmode != dr32(MacMode))
+               dw32(MacMode, macmode);
 }
 
 static void de_set_rx_mode (struct net_device *dev)
@@ -923,6 +920,7 @@
 static void de_set_media (struct de_private *de)
 {
        unsigned media = de->media_type;
+       u32 macmode = dr32(MacMode);
 
        if (de_is_running(de))
                BUG();
@@ -940,9 +938,9 @@
        mdelay(10);
 
        if (media == DE_MEDIA_TP_FD)
-               de->macmode |= FullDuplex;
+               macmode |= FullDuplex;
        else
-               de->macmode &= ~FullDuplex;
+               macmode &= ~FullDuplex;
        
        if (netif_msg_link(de)) {
                printk(KERN_INFO "%s: set link %s\n"
@@ -951,9 +949,11 @@
                       de->dev->name, media_name[media],
                       de->dev->name, dr32(MacMode), dr32(SIAStatus),
                       dr32(CSR13), dr32(CSR14), dr32(CSR15),
-                      de->dev->name, de->macmode, de->media[media].csr13,
+                      de->dev->name, macmode, de->media[media].csr13,
                       de->media[media].csr14, de->media[media].csr15);
        }
+       if (macmode != dr32(MacMode))
+               dw32(MacMode, macmode);
 }
 
 static void de_next_media (struct de_private *de, u32 *media,
@@ -1235,11 +1235,12 @@
 static int de_init_hw (struct de_private *de)
 {
        struct net_device *dev = de->dev;
+       u32 macmode;
        int rc;
 
        de_adapter_wake(de);
        
-       de->macmode = dr32(MacMode) & ~MacModeClear;
+       macmode = dr32(MacMode) & ~MacModeClear;
 
        rc = de_reset_mac(de);
        if (rc)
@@ -1250,7 +1251,7 @@
        dw32(RxRingAddr, de->ring_dma);
        dw32(TxRingAddr, de->ring_dma + (sizeof(struct de_desc) * 
DE_RX_RING_SIZE));
 
-       dw32(MacMode, RxTx | de->macmode);
+       dw32(MacMode, RxTx | macmode);
 
        dr32(RxMissed); /* self-clearing */
 
@@ -1501,7 +1502,7 @@
                break;
        }
        
-       if (de->macmode & FullDuplex)
+       if (dr32(MacMode) & FullDuplex)
                ecmd->duplex = DUPLEX_FULL;
        else
                ecmd->duplex = DUPLEX_HALF;