Messages in this thread | | | Date | Mon, 29 Sep 2008 06:42:20 -0700 | From | Arjan van de Ven <> | Subject | Re: [PATCH] pci: introduce users of ioremap_pcibar() |
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On Mon, 29 Sep 2008 01:26:43 -0600 Grant Grundler <grundler@parisc-linux.org> wrote: > > Alternatively, the ioremap_pcibar() code needs to check for > cacheable attribute and DTRT.
we should make it "if prefetchable, UC-, if not, hard UC", yes.
> > - core->lmmio = ioremap(pci_resource_start(pci, 0), > > - pci_resource_len(pci, 0)); > > + core->lmmio = ioremap_pcibar(pci, 0); > > Is there any easy way to tell if the device driver should be using > uncached mappings vs cacheable mappings? > (Just from looking at the source code) > > This patch changes that behavior of the device driver so it uses > uncacheable instead of cacheable mappings. This is the only thing > I'm uncertain about for this patch.
ioremap() also is uncachable today.
> > And I have a second issue less important issue. > What is the result of ioremap_pcibar(pci, 1) when BAR0 is a 64-bit > bar? Given the name, I expect to call "ioremap_pcibar(pci,2)" to get > the desired result. Maybe just document how to handle this correctly > in Documentation/pci.txt would be sufficient.
we should detect this and DTRT inside the implementation, not in the drivers.
-- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org
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