On Fri, 2009-02-20 at 15:33 +0300, Ivan Kokshaysky wrote: > On the other hand, there are PCI devices with 64-bit BARs that do not > work properly being placed above 4G boundary. Real life example: some > radeon cards have 64-bit bar for video RAM, but allocating that BAR in > the DAC area basically gives you framebuffer-only mode, hardware > acceleration won't work since the internal GPU is 32-bit... This is just a driver bug. IE. The driver tries to put the FB inside the card space at the same address as it sits on the PCI bus, and indeed that would break if that address is outside of the 32-bit space. But that's purely a driver issue. > So moving stuff into MEM64 area should be considered as generally > unsafe operation, and the best default policy is to not enable MEM64 > resource unless we find that BIOS has allocated something there. Right, I tend to agree. Cheers, Ben. -- 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
