From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jike Song <jike.song@intel.com>
Subject: Re: [PATCH 7/8] drm/i915: Create vgpu specific write
 MMIO to reduce traps
Date: Fri, 19 Sep 2014 15:43:43 +0800
Message-ID: <541BDEAF.3020709@intel.com>
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To: Chris Wilson <chris@chris-wilson.co.uk>
Cc: daniel.vetter@intel.com, intel-gfx@lists.freedesktop.org, "Zhang,
 Yu C" <yu.c.zhang@intel.com>
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[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@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