Resizable PCI BAR support V9

Bjorn Helgaas helgaas at
Tue Oct 24 19:44:38 UTC 2017

On Wed, Oct 18, 2017 at 03:58:16PM +0200, Christian K├Ânig wrote:
> Hi everyone,
> This is the ninth and hopefully last incarnation of this set of patches. It
> enables device drivers to resize and most likely also relocate the PCI BAR of
> devices they manage to allow the CPU to access all of the device local memory
> at once.
> This is very useful for GFX device drivers where the default PCI BAR is only
> about 256MB in size for compatibility reasons, but the device easily have
> multiple gigabyte of local memory.
> Some changes since the last version:
> 1. Rebased on drm-next, so should be ready to be merged for 4.15.
> 2. The fixup of the 64bit root window on AMD Family 15h CPUs/APUs is only
>    enabled when we compile a kernel supporting that hw.
> 3. Some minor error handling improvements for the amdgpu side. We now
>    gracefully abort driver loading in case of a critical error instead of
>    calling BUG().
> Bjorn any more comments or can we finally get this into 4.15? I will remove the
> version tags from the patches when I send you a pull request if you want this.
> I only work on this as a background task, so sorry for the ~3 month delay
> between each version of the patchset.

I put these (except for the last) on pci/resource for v4.15.  I'd be
happy to merge the last as well if you like.  My tree does not include
drm-next, so there would be a minor conflict when merging upstream.


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