Re: [PATCH v1 5/5] drm/xe/pt: Add an additional check for dmabuf BOs while updating PTEs

[Matthew Brost <matthew.brost@intel.com>]

On Fri, Oct 11, 2024 at 07:40:27PM -0700, Vivek Kasireddy wrote:
> If a BO's is_devmem_external flag is set, it means that it is an
> imported dmabuf BO that has a backing store in VRAM. Therefore, we
> need to add XE_PPGTT_PTE_DM to the PTE flags as part of vm_bind.
> 

So here if we land on a DPA cursor [1] we'd have to update the bind code
to use this cursor. Again I think this is my preference.

Matt

[1] https://patchwork.freedesktop.org/patch/619451/?series=139920&rev=1#comment_1127450

> Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_pt.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_pt.c b/drivers/gpu/drm/xe/xe_pt.c
> index f27f579f4d85..909e5b96d518 100644
> --- a/drivers/gpu/drm/xe/xe_pt.c
> +++ b/drivers/gpu/drm/xe/xe_pt.c
> @@ -660,10 +660,11 @@ xe_pt_stage_bind(struct xe_tile *tile, struct xe_vma *vma,
>  			xe_walk.default_pte &= ~XE_USM_PPGTT_PTE_AE;
>  	}
>  
> -	if (is_devmem) {
> +	if (is_devmem || bo->is_devmem_external)
>  		xe_walk.default_pte |= XE_PPGTT_PTE_DM;
> +
> +	if (is_devmem)
>  		xe_walk.dma_offset = vram_region_gpu_offset(bo->ttm.resource);
> -	}
>  
>  	if (!xe_vma_has_no_bo(vma) && xe_bo_is_stolen(bo))
>  		xe_walk.dma_offset = xe_ttm_stolen_gpu_offset(xe_bo_device(bo));
> -- 
> 2.45.1
>