[netdrvr] tulip: Better MWI workaround for 21143 rev 65 chip errata
This patch works around the MWI bug on the DC21143 rev 65 Tulip by
ensuring that the receive buffers don't end on a cache line boundary
(as documented in the errata).
This patch is required for the MIPS based Cobalt Qube/RaQ as
supporting the extra PCI commands seems to reduce the chance of a hard
lockup between the Tulip and the PCI bridge.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/net/tulip/tulip_core.c b/drivers/net/tulip/tulip_core.c
index 82f404b..fa1c1c3 100644
--- a/drivers/net/tulip/tulip_core.c
+++ b/drivers/net/tulip/tulip_core.c
@@ -1154,18 +1154,13 @@
tp->csr0 = csr0 = 0;
- /* if we have any cache line size at all, we can do MRM */
- csr0 |= MRM;
+ /* if we have any cache line size at all, we can do MRM and MWI */
+ csr0 |= MRM | MWI;
- /* ...and barring hardware bugs, MWI */
- if (!(tp->chip_id == DC21143 && tp->revision == 65))
- csr0 |= MWI;
-
- /* set or disable MWI in the standard PCI command bit.
- * Check for the case where mwi is desired but not available
+ /* Enable MWI in the standard PCI command bit.
+ * Check for the case where MWI is desired but not available
*/
- if (csr0 & MWI) pci_try_set_mwi(pdev);
- else pci_clear_mwi(pdev);
+ pci_try_set_mwi(pdev);
/* read result from hardware (in case bit refused to enable) */
pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
@@ -1401,10 +1396,6 @@
#ifdef CONFIG_TULIP_MWI
if (!force_csr0 && (tp->flags & HAS_PCI_MWI))
tulip_mwi_config (pdev, dev);
-#else
- /* MWI is broken for DC21143 rev 65... */
- if (chip_idx == DC21143 && pdev->revision == 65)
- tp->csr0 &= ~MWI;
#endif
/* Stop the chip's Tx and Rx processes. */