Re: One question about the useage of pci_dev->resource[]

[Richard Yang <weiyang@linux.vnet.ibm.com>]

On Wed, Jun 20, 2012 at 04:45:15PM +0800, Richard Yang wrote:
>All,
>
>I want to confirm something for the pci_dev->resource[].
>
>As in the definition in the pci.h, this resource array is divided into
>several parts.
>    0-5  for standard PCI resources
>    6    for ROM resource
>    7-10 for bridge resource( if no iov )
>
>
>1. For P2P bridge, 0-5 is left empty?
>2. If so, in code pci_setup_device(), I think it set the wrong resource.
>   It call pci_read_bases(dev, 2, PCI_ROM_ADDRESS1), for a p2p bridge. 
>   And in pci_read_bases(), BAR information is retrieved and set to
>   pci_dev->resource[0|1].
>3. If pci_setup_device() just set first two resource, the child bus will
>   point to empty resource.
>   In pci_alloc_child_bus(), child->resource[0-3] will be point to
>   bridge->resource[7-10], which is not set in pci_setup_device().
>4. Another question is, is there any convention for pci_bus->resource[].
>   [0] for io, [1] for mem, [2] for prefetch?
All,

I go through the code again and find pci_dev->resource[7-10] is used for
io/mem base/limit, which is used by the bridge to determine whether it
will forward one pci transaction.

So pci_dev->[0-1] is used by the bridge's driver?

If not exact, please correct me:)

>
>-- 
>Richard Yang
>Help you, Help me

-- 
Richard Yang
Help you, Help me