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    SubjectPCI resource allocation problem in 2.6.8
    I'm writing a driver for a PCI-based USB controller. The work is almost
    done but a few days ago something very ugly happened. I've tried to
    pinpoint the problem but everything is so simple and clear to be
    wrong... I really hope that someone can help me!

    OK, here's the problem:
    I'm using kernel 2.6.8 on an i386 arch. I want to allocate region 2 of
    my PCI board. Here's the output of lspci:

    0000:00:0e.0 Bridge: PLX Technology, Inc.: Unknown device 5406 (rev 0b)
    Subsystem: PLX Technology, Inc.: Unknown device 9054
    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-
    Latency: 32, Cache Line Size: 0x08 (32 bytes)
    Interrupt: pin A routed to IRQ 9
    Region 0: Memory at df100000 (32-bit, non-prefetchable)
    Region 1: I/O ports at e400 [size=256]
    Region 2: I/O ports at e800 [size=256]
    Region 3: Memory at df000000 (32-bit, non-prefetchable)
    Capabilities: [40] Power Management version 1
    Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
    Status: D0 PME-Enable- DSel=0 DScale=0 PME-
    Capabilities: [48] #06 [0000]
    Capabilities: [4c] Vital Product Data

    As you can see, region 2 begins at e800 and extends up to e8ff.

    When I try to claim the region, I get wrong start-end-length numbers.
    I've written something simple to demonstrate this fact:

    for(pci_region=0; pci_region < PCI_ROM_RESOURCE; pci_region++){
    resource_start = pci_resource_start (dev, pci_region);
    resource_end = pci_resource_end (dev,pci_region);
    printk (KERN_DEBUG "region:%d start:%lx, end:%lx - ", pci_region,
    resource_start, resource_end);
    len = pci_resource_len (dev, pci_region);
    printk(KERN_DEBUG "length:%lx\n", len);

    Where "dev" is a pointer to a pci device of course.
    So here's what I get by running this code:

    Nov 21 16:28:56 naousa kernel: PCI: Found IRQ 9 for device 0000:00:0e.0
    Nov 21 16:28:56 naousa kernel: region:0 start:0, end:0 - <7>length:0
    Nov 21 16:28:56 naousa kernel: region:1 start:df1000ff, end:200 -
    Nov 21 16:28:56 naousa kernel: region:2 start:e4ff, end:101 -
    Nov 21 16:28:56 naousa kernel: region:3 start:e8ff, end:101 -
    Nov 21 16:28:56 naousa kernel: region:4 start:df0fffff, end:200 -
    Nov 21 16:28:56 naousa kernel: region:5^Istart:0, end:0 - <7>length:0

    As you can see, what "start" claims to be is in reality the end of each
    region, and "end", "length" are nonsense...

    Any ideas? Is this something typical???
    I would appreciate any help, please CC me personally as I'm not yet
    subscribed to the list, or find me at the linux-usb-devel list.

    Thanx in advance,
    Dimitris Lampridis <>
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