> Currently, this can result in runtime PM issues on systems where memory
> Luckily, we don't actually need to allocate coherent memory for the page
> table thanks to being able to pass the GPU a radix3 page table for
> suspend/resume data. So, let's rewrite nvkm_gsp_radix3_sg() to use the sg
> allocator for level 2. We continue using coherent allocations for lvl0 and
> 1, since they only take a single page.
>
> Signed-off-by: Lyude Paul <lyude@xxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> ---
> .../gpu/drm/nouveau/include/nvkm/subdev/gsp.h | 4 +-
> .../gpu/drm/nouveau/nvkm/subdev/gsp/r535.c | 71 ++++++++++++-------
> 2 files changed, 47 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h b/drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h
> index 6f5d376d8fcc1..a11d16a16c3b2 100644
> --- a/drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h
> +++ b/drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h
> @@ -15,7 +15,9 @@ struct nvkm_gsp_mem {
> };
>
> struct nvkm_gsp_radix3 {
> - struct nvkm_gsp_mem mem[3];
> + struct nvkm_gsp_mem lvl0;
> + struct nvkm_gsp_mem lvl1;
> + struct sg_table lvl2;
This looks great, could we go a step further and combine lvl0 and lvl1
into a 2 page allocation, I thought we could combine lvl0/lvl1 into a
2 page alloc, but that actually might be a bad idea under memory
pressure.
Dave.
