Hi! We've number of UP2000+ boards (they just like DP264 in common). These boards has 2 PCI hoses, both has 3 PCI slots - one 32bits (IdSel=9) & two 64bits (IdSel=7,8) (6 slots in total). Recently we've tried to install 3c985b 64-bit card and observe the following: this card works just fine being inserted into 32bit slot - detected by Linux PCI code, gots real IRQ level. But we've tried to insert it onto the 64 bit slot we got problems. When inserted onto the slot with IdSel = 8 it's detected twice (!!!) - with IdSels 8 & 13! So, when pci code assign irqs & memory region it's do this twice - firstly for card with IdSel = 8 (which is "real" card and it gots "real" IRQ) and secondly for "phantom" with IdSel = 13 (and assigns IRQ 0 for it because DP264 knows nothing about IdSel 13). As the result 3c985 driver - acenic module sees 2 cards - the real card with valid IRQ (acenic read IRQ from kernel, not from card), but with invalid memory region (because this card was remaped for IdSel 13), and the second card with valid memory region, but with invalid IRQ == 0. Acenic when initialize "phantom", but works very slow... More fun comes when this card inserted onto the slot with IdSel = 7 - it's gets detected 32 times - with IdSel = 0..31 - i.e. entire pci bus! SRM detects this card only 6 times when IdSel = 7 and only once for IdSel = 8, 9 (but SRM knows which IdSels are valid on DP264).. So as seems 64bit 3c985b hardware is not fully comaptible with DP264. We've observe sismilar problems with Intel's EtherExpress PRO/1000 - it's also detected twice with IdSel = 7,12 when inserted onto the slot with IdSel = 7. -- lspci -- for Intel - Note device 01:0c.0 has no IRQ (i.e. IRQ == 0) 01:07.0 Ethernet controller: Intel Corporation: Unknown device 1001 (rev 02) Subsystem: Intel Corporation: Unknown device 1003 Flags: bus master, 66Mhz, medium devsel, latency 252, IRQ 47 Memory at 0000000109000000 (32-bit, non-prefetchable) Memory at 0000000109020000 (32-bit, non-prefetchable) Expansion ROM at 0000000001030000 [disabled] Capabilities: [dc] Power Management version 2 01:0c.0 Ethernet controller: Intel Corporation: Unknown device 1001 (rev 02) Subsystem: Intel Corporation: Unknown device 1003 Flags: bus master, 66Mhz, medium devsel, latency 252 Memory at 0000000109040000 (32-bit, non-prefetchable) Memory at 0000000109060000 (32-bit, non-prefetchable) Expansion ROM at 0000000001030000 [disabled] -- Sorry, for my bad english and explanations. Attached please find a patch against 2.2.16 - 2.2.19 kernels. This patch alters 3 files: include/asm-alpha/machvec.h - added new function to mv - pci_fixup_bus - just like X86 has, arch/alpha/kernel/bios32.c - added a in the pcibios_fixup_bus - to call a function from mv if any, arch/alpha/kernel/sys_dp264.c - dp264_pci_fixup_bus to disable phantoms. With this patch everything works just fine for me and we got really fast net. ;-)) -- lspci -vv 01:08.0 Ethernet controller: 3Com Corporation 3c985 1000BaseSX (rev 01) Subsystem: Unknown device 9850:0001 Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- Status: Cap- 66Mhz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- SERR-