Re: [PATCH drm-next v4 00/14] [RFC] DRM GPUVA Manager & Nouveau VM_BIND UAPI

[Danilo Krummrich]

Hi Donald,

On 6/9/23 13:56, Donald Robson wrote:
> On Wed, 2023-06-07 at 00:31 +0200, Danilo Krummrich wrote:
> > Christian König (1):
> >    drm: execution context for GEM buffers v4
> >
> > Danilo Krummrich (13):
> >    maple_tree: split up MA_STATE() macro
> >    drm: manager to keep track of GPUs VA mappings
>
> I have tested the drm GPUVA manager as part of using it with our new
> driver.  The link below shows use of the drm_gpuva_sm_[un]map()
> functions.  I think this is based on the v3 patches, but I have also
> tried it locally using v4 patches.  We will be submitting this
> driver for review soon.

That's awesome - thank your for taking the effort!

> https://gitlab.freedesktop.org/sarah-walker-imgtec/powervr/-/blob/dev/v3/drivers/gpu/drm/imagination/pvr_vm.c
>
> In a previous incarnation, I used the drm_gpuva_insert() and
> drm_gpuva_remove() functions directly.  In some now abandoned work I
> used the drm_gpuva_sm_[un]map_ops_create() route.
>
> The only problem I encountered along the way was the maple tree init
> issue already reported by Boris and fixed in v4.  One caveat - as
> our driver is a work in progress our testing is limited to certain
> Sascha Willem tests.
>
> I did find it quite difficult to get the prealloc route with
> drm_gpuva_sm_[un]map() working.  I'm not sure to what degree this
> reflects me being a novice on matters DRM, but I did find myself
> wishing for more direction, even with Boris's help.

I'm definitely up improving the existing documentation. Anything in 
particular you think should be described in more detail?

- Danilo

> Tested-by: Donald Robson <donald.robson@xxxxxxxxxx>
>
> >    drm: debugfs: provide infrastructure to dump a DRM GPU VA space
> >    drm/nouveau: new VM_BIND uapi interfaces
> >    drm/nouveau: get vmm via nouveau_cli_vmm()
> >    drm/nouveau: bo: initialize GEM GPU VA interface
> >    drm/nouveau: move usercopy helpers to nouveau_drv.h
> >    drm/nouveau: fence: separate fence alloc and emit
> >    drm/nouveau: fence: fail to emit when fence context is killed
> >    drm/nouveau: chan: provide nouveau_channel_kill()
> >    drm/nouveau: nvkm/vmm: implement raw ops to manage uvmm
> >    drm/nouveau: implement new VM_BIND uAPI
> >    drm/nouveau: debugfs: implement DRM GPU VA debugfs