Re: Linux MIPS PCI resource sanity check

[Sergei Shtylyov <sshtylyov@ru.mvista.com>]

Andrew Sharp wrote:

>>>There's a sanity check in pcibios_enable_resources() that looks
>>>like this:

>>>	r = &dev->resource[idx];
>>>	if (!r->start && r->end) {
>>>		printk(KERN_ERR "PCI: Device %s not available
>>>because of resource collisions\n", pci_name(dev)); return -EINVAL;
>>>	}

>>>What is this check actually doing?

>>   It makes sure that a PCI resource is allocated (base of 0 means
>>that it's unallocated due to previously detected resource conlict (or
>>some other reason).

> Actually, IIRC, resources are based on what the device requested, so a
> device behind a bridge could request a resource starting at 0.  I had

    Zero value in BAR was considered unallocated resource in the PCI 2.2 spec...

> to change this for a system as well.  I changed it to

> if (!r->start && !r->end) {

    r->end can't be 0.

WBR, Sergei