> -----Original Message----- > From: intel-gvt-dev [mailto:intel-gvt-dev-boun...@lists.freedesktop.org] On > Behalf Of Kirti Wankhede > Sent: Wednesday, July 12, 2017 8:45 PM > To: Zhang, Tina <tina.zh...@intel.com>; Gerd Hoffmann > <kra...@redhat.com>; Tian, Kevin <kevin.t...@intel.com>; linux- > ker...@vger.kernel.org; intel-...@lists.freedesktop.org; > alex.william...@redhat.com; zhen...@linux.intel.com; chris@chris- > wilson.co.uk; Lv, Zhiyuan <zhiyuan...@intel.com>; intel-gvt- > d...@lists.freedesktop.org; Wang, Zhi A <zhi.a.w...@intel.com> > Subject: Re: [PATCH v10] vfio: ABI for mdev display dma-buf operation > > > > On 7/12/2017 1:10 PM, Daniel Vetter wrote: > > On Wed, Jul 12, 2017 at 02:31:40AM +0000, Zhang, Tina wrote: > >> > >> > >>> -----Original Message----- > >>> From: intel-gvt-dev > >>> [mailto:intel-gvt-dev-boun...@lists.freedesktop.org] On Behalf Of > >>> Daniel Vetter > >>> Sent: Tuesday, July 11, 2017 5:13 PM > >>> To: Gerd Hoffmann <kra...@redhat.com> > >>> Cc: Tian, Kevin <kevin.t...@intel.com>; > >>> linux-kernel@vger.kernel.org; intel- g...@lists.freedesktop.org; > >>> alex.william...@redhat.com; zhen...@linux.intel.com; > >>> ch...@chris-wilson.co.uk; Kirti Wankhede <kwankh...@nvidia.com>; Lv, > >>> Zhiyuan <zhiyuan...@intel.com>; dan...@ffwll.ch; Zhang, Tina > >>> <tina.zh...@intel.com>; intel-gvt- d...@lists.freedesktop.org; Wang, > >>> Zhi A <zhi.a.w...@intel.com> > >>> Subject: Re: [PATCH v10] vfio: ABI for mdev display dma-buf > >>> operation > >>> > >>> On Tue, Jul 11, 2017 at 08:14:08AM +0200, Gerd Hoffmann wrote: > >>>> Hi, > >>>> > >>>>>> +struct vfio_device_query_gfx_plane { > >>>>>> + __u32 argsz; > >>>>>> + __u32 flags; > >>>>>> + struct vfio_device_gfx_plane_info plane_info; > >>>>>> + __u32 plane_type; > >>>>>> + __s32 fd; /* dma-buf fd */ > >>>>>> + __u32 plane_id; > >>>>>> +}; > >>>>>> + > >>>>> > >>>>> It would be better to have comment here about what are expected > >>>>> values for plane_type and plane_id. > >>>> > >>>> plane_type is DRM_PLANE_TYPE_*. > >>>> > >>>> yes, a comment saying so would be good, same for drm_format which > >>>> is DRM_FORMAT_*. While looking at these two: renaming plane_type > >>>> to drm_plane_type (for consistency) is probably a good idea too. > >>>> > >>>> plane_id needs a specification. > >>> > >>> Why do you need plane_type? With universal planes the plane_id along > >>> is sufficient to identify a plane on a given drm device instance. I'd just > remove it. > >>> -Daniel > >> The plane_type here, is to ask the mdev vendor driver to return the > information according to the value in field plane_type. So, it's a input > field. > >> The values in plane_type field is the same of drm_plane_type. And yes, it's > better to use drm_plane_type instead of plane_id. > > > > I have no idea what you mean here, I guess that just shows that > > discussing an ioctl struct without solid definitions of what field > > does what and why is not all that useful. What exactly it plane_id for then? > > > > plane type could be DRM_PLANE_TYPE_PRIMARY or > DRM_PLANE_TYPE_CURSOR. > > In case when VFIO region is used to provide surface to QEMU, plane_id would > be region index, for example region 10 could be used for primary surface and > region 11 could be used for cursor surface. So in that case, mdev vendor > driver > should return plane_type and its corresponding plane_id. Thanks, Kirti, do you mean there will be multiple DRM_PLANE_TYPE_PRIMARY and multiple DRM_PLANE_TYPE_CURSOR planes existing in the same time and region usage needs to use plane_id to distinguish among them? Is it for the multiple output or that's the typical way of region usage? Thanks.
Tina > > Thanks, > Kirti > > > This just confused me more ... > > -Daniel > > > _______________________________________________ > intel-gvt-dev mailing list > intel-gvt-...@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gvt-dev
