I noticed that at 79896cf42f Linus changed the function from insert_resource() to request_resource() (and later evolved into request_resource_conflict()) and he explained the reason. So, in the NIC's case, the problem is that in pci_claim_resource() the function pci_find_parent_resource() returns the root (0x0-0xffffff) rather than the MSC PCI I/O (0x1000-0xffffff). So request_resource_conflict() for PCI quirks (0x1000-0x103f and 0x1100-0x110f) will simply return an error, coz these 2 regions 'conflict' with MSC PCI I/O. Instead, insert_resource_conflict() will also find the collisions but register quirks as children of MSC PCI I/O (is this supposed to be correct?) and return a success. Deng-Cheng 2011/7/28 Ralf Baechle <ralf@xxxxxxxxxxxxxx> > > On Thu, Jul 28, 2011 at 07:28:31PM +0800, Deng-Cheng Zhu wrote: > > > In resolving a network driver issue with the MIPS Malta platform, the root > > cause was traced into pci_claim_resource(): > > > > MIPS System Controller's PCI I/O resources stay in 0x1000-0xffffff. When > > PCI quirks start claiming resources using request_resource_conflict(), > > collisions happen and -EBUSY is returned, thereby rendering the onboard AMD > > PCnet32 NIC unaware of quirks' region and preventing the NIC from functioning. > > For PCI quirks, PIIX4 ACPI is expected to claim 0x1000-0x103f, and PIIX4 SMB to > > claim 0x1100-0x110f, both of which fall into the MSC I/O range. Certainly, we > > can increase the start point of this range in arch/mips/mti-malta/malta-pci.c to > > avoid the collisions. But a fix in here looks more justified, though it seems to > > have a wider impact. Using insert_xxx as opposed to request_xxx will register > > PCI quirks' resources as children of MSC I/O and return OK, instead of seeing > > collisions which are actually resolvable. > > This used to work in the past; do you know which commit broke the resource > handling for the NIC? > > Ralf
