Commit 1a74fc0b authored by Ville Syrjälä's avatar Ville Syrjälä
Browse files

drm/i915: Add a new "remapped" gtt_view 



To overcome display engine stride limits we'll want to remap the
pages in the GTT. To that end we need a new gtt_view type which
is just like the "rotated" type except not rotated.

v2: Use intel_remapped_plane_info base type
    s/unused/unused_mbz/ (Chris)
    Separate BUILD_BUG_ON()s (Chris)
    Use I915_GTT_PAGE_SIZE (Chris)
v3: Use i915_gem_object_get_dma_address() (Chris)
    Trim the sg (Tvrtko)
v4: Actually trim this time. Limit the max length
    to one row of pages to keep things simple

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190509122159.24376-2-ville.syrjala@linux.intel.com


Reviewed-by: default avatarMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
parent 4cc79cbb

drivers/gpu/drm/i915/i915_debugfs.c

+12 −0
Original line number Diff line number Diff line
@@ -212,6 +212,18 @@ describe_obj(struct seq_file *m, struct drm_i915_gem_object *obj) 
					   vma->ggtt_view.rotated.plane[1].offset);

				break;



			case I915_GGTT_VIEW_REMAPPED:

				seq_printf(m, ", remapped [(%ux%u, stride=%u, offset=%u), (%ux%u, stride=%u, offset=%u)]",

					   vma->ggtt_view.remapped.plane[0].width,

					   vma->ggtt_view.remapped.plane[0].height,

					   vma->ggtt_view.remapped.plane[0].stride,

					   vma->ggtt_view.remapped.plane[0].offset,

					   vma->ggtt_view.remapped.plane[1].width,

					   vma->ggtt_view.remapped.plane[1].height,

					   vma->ggtt_view.remapped.plane[1].stride,

					   vma->ggtt_view.remapped.plane[1].offset);

				break;



			default:

				MISSING_CASE(vma->ggtt_view.type);

				break;

drivers/gpu/drm/i915/i915_drv.h

+4 −0
Original line number Diff line number Diff line
@@ -2864,6 +2864,10 @@ i915_gem_object_get_dirty_page(struct drm_i915_gem_object *obj, 
			       unsigned int n);



dma_addr_t

i915_gem_object_get_dma_address_len(struct drm_i915_gem_object *obj,

				    unsigned long n,

				    unsigned int *len);

dma_addr_t

i915_gem_object_get_dma_address(struct drm_i915_gem_object *obj,

				unsigned long n);

drivers/gpu/drm/i915/i915_gem.c

+15 −2
Original line number Diff line number Diff line
@@ -5081,16 +5081,29 @@ i915_gem_object_get_dirty_page(struct drm_i915_gem_object *obj, 
}



dma_addr_t

i915_gem_object_get_dma_address(struct drm_i915_gem_object *obj,

				unsigned long n)

i915_gem_object_get_dma_address_len(struct drm_i915_gem_object *obj,

				    unsigned long n,

				    unsigned int *len)

{

	struct scatterlist *sg;

	unsigned int offset;



	sg = i915_gem_object_get_sg(obj, n, &offset);



	if (len)

		*len = sg_dma_len(sg) - (offset << PAGE_SHIFT);



	return sg_dma_address(sg) + (offset << PAGE_SHIFT);

}



dma_addr_t

i915_gem_object_get_dma_address(struct drm_i915_gem_object *obj,

				unsigned long n)

{

	return i915_gem_object_get_dma_address_len(obj, n, NULL);

}





int i915_gem_object_attach_phys(struct drm_i915_gem_object *obj, int align)

{

	struct sg_table *pages;

drivers/gpu/drm/i915/i915_gem_gtt.c

+88 −0
Original line number Diff line number Diff line
@@ -3608,6 +3608,89 @@ err_st_alloc: 
	return ERR_PTR(ret);

}



static struct scatterlist *

remap_pages(struct drm_i915_gem_object *obj, unsigned int offset,

	    unsigned int width, unsigned int height,

	    unsigned int stride,

	    struct sg_table *st, struct scatterlist *sg)

{

	unsigned int row;



	for (row = 0; row < height; row++) {

		unsigned int left = width * I915_GTT_PAGE_SIZE;



		while (left) {

			dma_addr_t addr;

			unsigned int length;



			/* We don't need the pages, but need to initialize

			 * the entries so the sg list can be happily traversed.

			 * The only thing we need are DMA addresses.

			 */



			addr = i915_gem_object_get_dma_address_len(obj, offset, &length);



			length = min(left, length);



			st->nents++;



			sg_set_page(sg, NULL, length, 0);

			sg_dma_address(sg) = addr;

			sg_dma_len(sg) = length;

			sg = sg_next(sg);



			offset += length / I915_GTT_PAGE_SIZE;

			left -= length;

		}



		offset += stride - width;

	}



	return sg;

}



static noinline struct sg_table *

intel_remap_pages(struct intel_remapped_info *rem_info,

		  struct drm_i915_gem_object *obj)

{

	unsigned int size = intel_remapped_info_size(rem_info);

	struct sg_table *st;

	struct scatterlist *sg;

	int ret = -ENOMEM;

	int i;



	/* Allocate target SG list. */

	st = kmalloc(sizeof(*st), GFP_KERNEL);

	if (!st)

		goto err_st_alloc;



	ret = sg_alloc_table(st, size, GFP_KERNEL);

	if (ret)

		goto err_sg_alloc;



	st->nents = 0;

	sg = st->sgl;



	for (i = 0 ; i < ARRAY_SIZE(rem_info->plane); i++) {

		sg = remap_pages(obj, rem_info->plane[i].offset,

				 rem_info->plane[i].width, rem_info->plane[i].height,

				 rem_info->plane[i].stride, st, sg);

	}



	i915_sg_trim(st);



	return st;



err_sg_alloc:

	kfree(st);

err_st_alloc:



	DRM_DEBUG_DRIVER("Failed to create remapped mapping for object size %zu! (%ux%u tiles, %u pages)\n",

			 obj->base.size, rem_info->plane[0].width, rem_info->plane[0].height, size);



	return ERR_PTR(ret);

}



static noinline struct sg_table *

intel_partial_pages(const struct i915_ggtt_view *view,

		    struct drm_i915_gem_object *obj)
@@ -3686,6 +3769,11 @@ i915_get_ggtt_vma_pages(struct i915_vma *vma) 
			intel_rotate_pages(&vma->ggtt_view.rotated, vma->obj);

		break;



	case I915_GGTT_VIEW_REMAPPED:

		vma->pages =

			intel_remap_pages(&vma->ggtt_view.remapped, vma->obj);

		break;



	case I915_GGTT_VIEW_PARTIAL:

		vma->pages = intel_partial_pages(&vma->ggtt_view, vma->obj);

		break;

drivers/gpu/drm/i915/i915_gem_gtt.h

+21 −4
Original line number Diff line number Diff line
@@ -163,11 +163,18 @@ typedef u64 gen8_ppgtt_pml4e_t; 


struct sg_table;



struct intel_rotation_info {

	struct intel_rotation_plane_info {

		/* tiles */

struct intel_remapped_plane_info {

	/* in gtt pages */

	unsigned int width, height, stride, offset;

	} plane[2];

} __packed;



struct intel_remapped_info {

	struct intel_remapped_plane_info plane[2];

	unsigned int unused_mbz;

} __packed;



struct intel_rotation_info {

	struct intel_remapped_plane_info plane[2];

} __packed;



struct intel_partial_info {
@@ -179,12 +186,20 @@ enum i915_ggtt_view_type { 
	I915_GGTT_VIEW_NORMAL = 0,

	I915_GGTT_VIEW_ROTATED = sizeof(struct intel_rotation_info),

	I915_GGTT_VIEW_PARTIAL = sizeof(struct intel_partial_info),

	I915_GGTT_VIEW_REMAPPED = sizeof(struct intel_remapped_info),

};



static inline void assert_i915_gem_gtt_types(void)

{

	BUILD_BUG_ON(sizeof(struct intel_rotation_info) != 8*sizeof(unsigned int));

	BUILD_BUG_ON(sizeof(struct intel_partial_info) != sizeof(u64) + sizeof(unsigned int));

	BUILD_BUG_ON(sizeof(struct intel_remapped_info) != 9*sizeof(unsigned int));



	/* Check that rotation/remapped shares offsets for simplicity */

	BUILD_BUG_ON(offsetof(struct intel_remapped_info, plane[0]) !=

		     offsetof(struct intel_rotation_info, plane[0]));

	BUILD_BUG_ON(offsetofend(struct intel_remapped_info, plane[1]) !=

		     offsetofend(struct intel_rotation_info, plane[1]));



	/* As we encode the size of each branch inside the union into its type,

	 * we have to be careful that each branch has a unique size.
@@ -193,6 +208,7 @@ static inline void assert_i915_gem_gtt_types(void) 
	case I915_GGTT_VIEW_NORMAL:

	case I915_GGTT_VIEW_PARTIAL:

	case I915_GGTT_VIEW_ROTATED:

	case I915_GGTT_VIEW_REMAPPED:

		/* gcc complains if these are identical cases */

		break;

	}
@@ -204,6 +220,7 @@ struct i915_ggtt_view { 
		/* Members need to contain no holes/padding */

		struct intel_partial_info partial;

		struct intel_rotation_info rotated;

		struct intel_remapped_info remapped;

	};

};

CRA Git | Maintained and supported by SUSTech CRA and CCSE