>-----Original Message----- >From: amd-gfx <amd-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx> On Behalf Of Deng, >Emily >Sent: Friday, December 21, 2018 5:10 PM >To: Michel Dänzer <michel@xxxxxxxxxxx> >Cc: amd-gfx@xxxxxxxxxxxxxxxxxxxxx >Subject: RE: [PATCH] drm/amdgpu/virtual_dce: Need to pin the fb's bo > >>-----Original Message----- >>From: Michel Dänzer <michel@xxxxxxxxxxx> >>Sent: Friday, December 21, 2018 4:52 PM >>To: Deng, Emily <Emily.Deng@xxxxxxx> >>Cc: amd-gfx@xxxxxxxxxxxxxxxxxxxxx >>Subject: Re: [PATCH] drm/amdgpu/virtual_dce: Need to pin the fb's bo >> >>On 2018-12-21 9:45 a.m., Deng, Emily wrote: >>>> -----Original Message----- >>>> From: Michel Dänzer <michel@xxxxxxxxxxx> >>>> Sent: Friday, December 21, 2018 4:38 PM >>>> To: Deng, Emily <Emily.Deng@xxxxxxx> >>>> Cc: amd-gfx@xxxxxxxxxxxxxxxxxxxxx >>>> Subject: Re: [PATCH] drm/amdgpu/virtual_dce: Need to pin the fb's bo >>>> >>>> On 2018-12-21 8:26 a.m., Emily Deng wrote: >>>>> When the bo is used to set mode, the bo need to be pinned. >>>> >>>> On second thought, why does the BO need to be pinned? When using the >>>> display hardware, the BO needs to be pinned to prevent it from being >>>> moved while the hardware is scanning out from it, but that shouldn't >>>> be >>necessary here. >>> The pin here is used for scan out the buffer by remote display app. >> >>I still don't understand why pinning is needed. What mechanism does the >>remote display app use to access the BO contents? >Sorry, I am not familiar with the remote display app. Maybe it will use drm ioctl >function to get the current crtc's fb's information, and get the content in the fb's >buffer object by mmap or translate the bo to an OpenGL texture for next >rendering. Maybe don't need to pin the bo here, as the use has no different with >other normal bos. So please ignore the patch, and will send another patch to >remove the unpin the fb's bo code. It seems to be hard to remove all the pin for virtual_dce, as it uses some common code in amdgpu_display.c. So for code consistency, maybe still need to add the pin here. Best wishes Emily Deng >> >> >>-- >>Earthling Michel Dänzer | http://www.amd.com >>Libre software enthusiast | Mesa and X developer >_______________________________________________ >amd-gfx mailing list >amd-gfx@xxxxxxxxxxxxxxxxxxxxx >https://lists.freedesktop.org/mailman/listinfo/amd-gfx _______________________________________________ amd-gfx mailing list amd-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/amd-gfx
