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

From: Donald Robson
Date: Fri Jun 09 2023 - 08:51:10 EST


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.

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.

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
>