Messages in this thread | | | Subject | Re: [PATCHv2] PCI: QDF2432 32 bit config space accessors | From | Jon Masters <> | Date | Thu, 1 Dec 2016 23:58:52 -0500 |
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On 11/03/2016 10:00 AM, Bjorn Helgaas wrote:
> It turns out that we can't use the _CRS of host bridges because of the > Producer/Consumer bit screwup [1]. So the fallback is to include the > ECAM space in the _CRS of a PNP0C02 device. This is what the PCI > Firmware spec r3.0, Table 4-2, footnote 2 is talking about. > > Bjorn > > [1] The original ACPI spec intent was that Consumer resources would be > space like ECAM that is consumed directly by the bridge, and Producer > resources would be the windows forwarded down to PCI. But BIOSes > didn't use the Producer/Consumer bit consistently, so we have to > assume that all resources in host bridge _CRS are windows, which > leaves us no way to describe the Consumer resources.
Aside - and now I realize you'd called this out as recently as last month. Alas the HPE m400 I reference on the other thread about the APM quirks doesn't have the motherboard resource entry so we're stuck with exactly the situation you describe above there.
Jon.
-- Computer Architect | Sent from my Fedora powered laptop
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