[Intel-gfx] [PATCH 7/8] drm/i915: Create vgpu specific write MMIO to reduce traps

[Jike Song]

[adding cc. By mistake I set suppresscc=all in my ~/.gitconfig]

On 09/19/2014 02:59 PM, Chris Wilson wrote:
> On Sat, Sep 20, 2014 at 02:47:07AM +0800, Jike Song wrote:
>> From: Yu Zhang <yu.c.zhang at intel.com>
>>
>> In the virtualized environment, forcewake operations are not
>> necessory for the driver, because mmio accesses will be trapped
>> and emulated by the host side, and real forcewake operations are
>> also done in the host. New mmio write handlers are added to directly
>> call the __raw_i915_write, therefore will reduce many traps and
>> increase the overall performance for drivers runing in the VM
>> with Intel GVT-g enhancement
>
> Explain why this is not done inside uncore_init.
> -Chris

Hi Chris,

  The gpu_active flag is set by intel_detect_vgpu(), which uses I915_READxx, should be after intel_uncore_init.


--
Thanks,
Jike