[Intel-gfx] [PATCH v2 02/15] drm/i915/ttm: require mappable by default

[Thomas Hellström]

On 2/10/22 13:13, Matthew Auld wrote:
> On devices with non-mappable LMEM ensure we always allocate the pages
> within the mappable portion. For now we assume that all LMEM buffers
> will require CPU access, which is also inline with pretty much all
> current kernel internal users. In the next patch we will introduce a new
> flag to override this behaviour.
>
> Signed-off-by: Matthew Auld <matthew.auld at intel.com>
> Cc: Thomas Hellström <thomas.hellstrom at linux.intel.com>
> ---
>   drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 4 ++++
>   drivers/gpu/drm/i915/intel_region_ttm.c | 5 +++++
>   2 files changed, 9 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
> index e9399f7b3e67..41e94d09e742 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
> @@ -128,6 +128,10 @@ i915_ttm_place_from_region(const struct intel_memory_region *mr,
>   
>   	if (flags & I915_BO_ALLOC_CONTIGUOUS)
>   		place->flags = TTM_PL_FLAG_CONTIGUOUS;
> +	if (mr->io_size && mr->io_size < mr->total) {
> +		place->fpfn = 0;
> +		place->lpfn = mr->io_size >> PAGE_SHIFT;
> +	}
>   }
>   
>   static void
> diff --git a/drivers/gpu/drm/i915/intel_region_ttm.c b/drivers/gpu/drm/i915/intel_region_ttm.c
> index f2b888c16958..4689192d5e8d 100644
> --- a/drivers/gpu/drm/i915/intel_region_ttm.c
> +++ b/drivers/gpu/drm/i915/intel_region_ttm.c
> @@ -199,6 +199,11 @@ intel_region_ttm_resource_alloc(struct intel_memory_region *mem,
>   	struct ttm_resource *res;
>   	int ret;
>   
> +	if (mem->io_size && mem->io_size < mem->total) {
> +		place.fpfn = 0;
> +		place.lpfn = mem->io_size >> PAGE_SHIFT;
> +	}
> +
>   	mock_bo.base.size = size;
>   	place.flags = flags;
>   

Reviewed-by: Thomas Hellström <thomas.hellstrom at linux.intel.com>