On Fri, Jun 24, 2011 at 09:15:24AM -0700, Jesse Barnes wrote: > On Thu, 23 Jun 2011 23:16:57 -0500 > Xianghua Xiao <xiaoxianghua@xxxxxxxxx> wrote: > > > We're using a ARM that only has 256MB PCI space, however I have a PCI > > device that has a BAR(for its own memory) that is 512MB, for ARM to > > allocate it I modified the BAR size on the device to 128MB(there are > > other PCI devices to use portion of the rest 128MB) > > > > I can modify the BAR at run time, is it ok for me to change the BAR > > address to address all the 512MB on PCI device? The PCI memory address > > ARM allocates at boot time can stay the same, but the BAR will be > > changed to re-map to all the 512MB space on the PCI device(each time > > for 128M), is this do-able? > > Sounds pretty hackish, but as long as you can deal with the decode > priorities for the address space on your platform (e.g. make sure your > 512M device doesn't start decoding cycles meant for RAM or some other > fixed resource region) then doing the above should be possible. I doubt it's possible ... it'd only be possible if the 256MB PCI address space were not aligned to a 256MB boundary. And nobody builds systems like that. -- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step." -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
