Messages in this thread | | | Date | Fri, 30 Nov 2012 17:49:48 -0700 | From | Jason Gunthorpe <> | Subject | Re: [PATCH] of: When constructing the bus id consider assigned-addresses as well |
| |
On Fri, Nov 30, 2012 at 09:48:05AM +0000, Grant Likely wrote:
> > If you attempt to stick a 'reg' in a block nested below a > > 'device_type="pci"' the kernel throws lots of error messsages and > > generates bad address mappings. > > Have you added the appropriate #address-cells and #size-cells to the pci > device node to go back to a non-pci addressing mode? > assigned-addresses
Switching away from the 5 dword address format is not ideal because then there is no way to specify the resource region (prefetch, io, mmio) and mmio would have to be assumed.
> only makes sense in the pci-device node itself. reg should work for all > nodes below that, and if it doesn't then it is a bug that we need to > fix.
Okay.. but how should the DTS be constructed?
pcie_bus { // The PCI-E bus device_type = "pci"; ranges = <5dw ranges>; #address-cells = <3>; #size-cells = <2>; soc_bridge { // The PCI-E device device_type = "pci"; ranges = <5dw ranges>;
soc_device { // Internal device assigned-address = <5dw regs> }; }; };
This is what I have now, the soc_bridge PCI-E device is DTS modeled as a PCI bridge - it has a ranges with its memory location, and the children nodes are relative to those ranges. This would not be typical for a non-bridge PCI-E device.
The reason for the 'assigned-address' requirement with the current kernel code is the device_type=pci on soc_bridge. This makes of_match_bus(parent) for soc_device return the PCI structure, which has '.addresses = "assigned-addresses",'
So.. how would you like this to look?
Jason
| |