Messages in this thread | | | Date | Mon, 30 Nov 2009 16:58:38 -0700 | From | Grant Grundler <> | Subject | Re: [PATCH] PCI: Always set prefetchable base/limit upper32 registers |
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On Mon, Nov 30, 2009 at 01:52:03PM -0800, Yinghai Lu wrote: > if HW state that reg is only 32bit pref, > why should we care about the upper 32bit?
pref_mem64 describes the resource, not the HW.
All the PCI specs define Type 1 configuration space with Prefetchable Memory register as 64-bit. Even if the Type 1 (PCI Bridge) HW ignores this register. See "7.5.3. Type 1 Configuration Space Header" of PCI EXPRESS BASE SPECIFICATION, REV. 1.1.
> looks like that your bridge device need quirk to clear that so called > upper 32bit for it.
Hrm...I don't think this is a quirk. PCI spec defines 64-bit PrefMem window register regardless of what type of resource we program into it.
hth, grant
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