strange PCI resource behaviour in 2.4
flat view
From: David Monro <hidden>
Date: 2000-08-24 01:03:19
Hi, I'm seeing a strange problem with the PCI code on 2.4. What is happening is that the PCI code seems to be detecting a memory region on my pcnet32 chip, but leaving it at 0x0: prozac:~# lspci -v -vv -s 0c 00:0c.0 Ethernet controller: Advanced Micro Devices [AMD] 79c970 [PCnet LANCE] (rev 16) Control: I/O- Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- Status: Cap- 66Mhz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- Interrupt: pin A routed to IRQ 15 Region 0: I/O ports at 1000200 [disabled] [size=32] Region 1: Memory at <unassigned> (32-bit, non-prefetchable) [disabled] [size=32] Expansion ROM at <unassigned> [disabled] [size=64K] (On a 2.2 kernel, Region 1 and the Expansion ROM simply aren't there, presumably bacuse the firmware doesn't enable them.) This means when the device driver calls pci_enable_device, it doesn't work. excerpt from dmesg: pcnet32_probe_pci: found device 0x001022.0x002000 ioaddr=0x1000200 resource_flags=0x000101 PCI: Device 00:0c.0 not available because of resource collisions pcnet32.c: failed to enable device -- err=-22 This is because the code in pcibios_enable_device() checks for the combination of a region with a base of 0 and a non-0 end and fails if that is the case. I guess this is a consequence of the new code which searches for pci regions rather then just accepting what the bios gives it. Should I make it assign a sensible base address to the regions it finds, or fix it so that the end address is also 0 if the start address is left at 0? Where should the fix go? Note that I don't get any "PCI: Address space collision on region ..." messages while booting, so the initialization code doesn't seem to think there is a problem at any stage. This is using an IBM 850. Cheers, Davvid ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/