Messages in this thread | | | Date | Wed, 5 Sep 2012 14:30:10 +0100 | From | Alan Cox <> | Subject | Re: [PATCH V3 3/4] PCI: Add support for non-BAR ROMs |
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On Wed, 5 Sep 2012 14:20:07 +0100 Matthew Garrett <mjg@redhat.com> wrote:
> On Wed, Sep 05, 2012 at 01:46:21PM +0100, Alan Cox wrote: > > On Wed, 5 Sep 2012 03:29:32 +0100 > > Matthew Garrett <mjg@redhat.com> wrote: > > > > > On Tue, Sep 04, 2012 at 10:18:48PM -0400, Don Dutile wrote: > > > > > /* > > > > >+ * Some devices may provide ROMs via a source other than the BAR > > > > >+ */ > > > > >+ if (pdev->rom&& pdev->romlen) { > > > > >+ *size = pdev->romlen; > > > > >+ return phys_to_virt((phys_addr_t)pdev->rom); > > > > ^^^^^ > > > > ioremap_nocache() ? ... or is caching rom ok? > > > > > > If it's appearing through this pathway then it's not actually in ROM, > > > the platform has pulled it out of somewhere else. > > > > If that somewhere else is on the PCI bus then it should be a bus not a > > virt translation surely ? > > We've no good way of knowing what the firmware's giving us - we copy it > to RAM in the EFI init process, so by the time we're here it certainly > shouldn't be on the PCI bus.
In which case how do you know that physical address you have been given actually has a mapping in kernel virtual space. It seems like it ought to be getting an ioremap in that case ?
phys_to_virt is not valid for arbitary addresses.
Alan
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