On Tue, Jul 20, 2004 at 09:23:49AM -0700, Wayne Gowcher wrote: > I am having a problem with a Ti cardbus chip and yenta > on the 2.6.4 mips kernel whereby when yenta tries to > configure the cardbus chip, it finds all the resources > busy ( because they have already been allocated in the > pci driver ) and so starts allocating new ones. > > Here's the output of the PCI driver > > PCI: Bus 1, cardbus bridge: 0000:00:0c.0 > IO window: 00001000-00001fff > IO window: 00002000-00002fff > PREFETCH window: 40000000-41ffffff > MEM window: 42000000-43ffffff > PCI: Bus 5, cardbus bridge: 0000:00:0c.1 > IO window: 00003000-00003fff > IO window: 00004000-00004fff > PREFETCH window: 44000000-45ffffff > MEM window: 46000000-47ffffff > > and here's what yenta reports: > > Yenta: CardBus bridge found at 0000:00:0c.0 > [0000:0000] > yenta 0000:00:0c.0: Preassigned resource 1 busy, > reconfiguring... > Yenta: CardBus bridge found at 0000:00:0c.1 > [0000:0000] > > > When I run the same 2.6.4 kernel compiled for x86 on a > x86 laptop, the x86 kernel finds the bar 0 registers > of the cardbus chip and adds them to it's resource > space, but probes no further. So that later when yenta > probes the cardbus chip, it can allocate the resources > without conflict. > > I also found the following comment in > drivers/pci/probe.c pci_scan_bridge : > > * If it's a bridge, configure it and scan the bus > behind it. > * For CardBus bridges, we don't scan behind as the > devices will > * be handled by the bridge driver itself. > > But the code does scan behind teh cardbus bridge and > add resources to iomem_resources and ioport_resources. > > So as I wrote in my title, does anyone know if : > > the pci driver should probe behind a cardbus bridge at > boot up or if it should be left to the yenta cardbus ? > It should not - me think anyway. Maybe you can tell us _why_, given the same code, i386 does not scan behind yenta. Jun
