Messages in this thread | | | Subject | Re: [PATCH] of: treat PCI config space as IORESOURCE_MEM type | From | Kumar Gala <> | Date | Fri, 30 May 2014 15:44:18 -0500 |
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On May 30, 2014, at 3:37 PM, Jason Gunthorpe <jgunthorpe@obsidianresearch.com> wrote:
> On Fri, May 30, 2014 at 02:41:17AM +0100, Liviu Dudau wrote: > >> Agree, I'm only concerned that if this ECAM config space gets added to >> the list of pci_host_bridge windows it will be indistinguishable from >> IORESOURCE_MEM resources and pci_create_root_bus() will add it to the >> bus and allow devices present on that bus to be assigned addresses from >> that range. Which might not be what one wants for certain BARs. > > I wouldn't worry about supporting config in ranges. ECAM is the > logical use for config ranges, but it isn't specified and probably > will never be. > > Will's driver the is the only driver I've seen to support ECAM and it > didn't use ranges.
I expect with 64-bit parts we will see more use of ECAM, I think the reason its not used much is because of the address space it chews up, but that becomes less of an issue with LPAE or 64-bit parts with larger physical address spaces.
- k
-- Employee of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
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