[Intel-gfx] [RFC 01/10] drm/i915/gvt: add module parameter enable_pvmmio

[Zhang, Xiaolin]

On 10/09/2018 10:34 AM, Zhenyu Wang wrote:
> On 2018.09.28 14:09:45 +0800, Zhang, Xiaolin wrote:
>> On 09/27/2018 07:03 PM, Joonas Lahtinen wrote:
>>> Quoting Xiaolin Zhang (2018-09-27 19:37:46)
>>>> This int type module parameter is used to control the different
>>>> level pvmmio feature for MMIO emulation in GVT.
>>>>
>>>> This parameter is default zero, no pvmmio feature enabled.
>>>>
>>>> Its permission type is 0400 which means user could only change its
>>>> value through the cmdline, this is to prevent the dynamic modification
>>>> during runtime which would break the pvmmio internal logic.
>>>>
>>>> Signed-off-by: Xiaolin Zhang <xiaolin.zhang at intel.com>
>>> This shouldn't really be a module parameter. We should detect the
>>> capability from the vGPU device and use it always when possible.
>>>
>>> Regards, Joonas
>>>
>> for pv optimization, we should touch both guest driver and GVTg.  this
>> parameter is used for
>>
>> guest pv capability because GVTg with pv capability will support both pv
>> and non pv capability guest.
>>
> That's the purpose of 'vgt_caps' in PVINFO to do capability check between
> host/guest. You need a new cap bit definition for PVMMIO and maybe another
> field for different PVMMIO level capability check. New parameter is not useful here.
>
> Thanks
>
Sounds good to me. Will to use it in the next version.  thanks very much.

BRs, Xiaolin