[Intel-gfx] [PATCH v2 32/38] drm/i915: Verify page layout for rotated VMA

[Tvrtko Ursulin]

On 19/01/2017 11:41, Chris Wilson wrote:
> Exercise creating rotated VMA and checking the page order within.
>
> v2: Be more creative in rotated params
>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> ---
>  drivers/gpu/drm/i915/selftests/i915_vma.c | 177 ++++++++++++++++++++++++++++++
>  1 file changed, 177 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/selftests/i915_vma.c b/drivers/gpu/drm/i915/selftests/i915_vma.c
> index b45b392444e4..2bda93f53b47 100644
> --- a/drivers/gpu/drm/i915/selftests/i915_vma.c
> +++ b/drivers/gpu/drm/i915/selftests/i915_vma.c
> @@ -310,11 +310,188 @@ static int igt_vma_pin1(void *arg)
>  	return err;
>  }
>
> +static unsigned long rotated_index(const struct intel_rotation_info *r,
> +				   unsigned int n,
> +				   unsigned int x,
> +				   unsigned int y)
> +{
> +	return (r->plane[n].stride * (r->plane[n].height - y - 1) +
> +		r->plane[n].offset + x);
> +}
> +
> +static struct scatterlist *
> +assert_rotated(struct drm_i915_gem_object *obj,
> +	       const struct intel_rotation_info *r, unsigned int n,
> +	       struct scatterlist *sg)
> +{
> +	unsigned int x, y;
> +
> +	for (x = 0; x < r->plane[n].width; x++) {
> +		for (y = 0; y < r->plane[n].height; y++) {
> +			unsigned long src_idx;
> +			dma_addr_t src;
> +
> +			src_idx = rotated_index(r, n, x, y);
> +			src = i915_gem_object_get_dma_address(obj, src_idx);
> +
> +			if (sg_dma_len(sg) != PAGE_SIZE) {
> +				pr_err("Invalid sg.length, found %d, expected %lu for rotated page (%d, %d) [src index %lu]\n",
> +				       sg_dma_len(sg), PAGE_SIZE,
> +				       x, y, src_idx);
> +				return ERR_PTR(-EINVAL);
> +			}
> +
> +			if (sg_dma_address(sg) != src) {
> +				pr_err("Invalid address for rotated page (%d, %d) [src index %lu]\n",
> +				       x, y, src_idx);
> +				return ERR_PTR(-EINVAL);
> +			}
> +
> +			sg = ____sg_next(sg);
> +		}
> +	}
> +
> +	return sg;
> +}
> +
> +static unsigned int rotated_size(const struct intel_rotation_plane_info *a,
> +				 const struct intel_rotation_plane_info *b)
> +{
> +	return a->width * a->height + b->width * b->height;
> +}
> +
> +static int igt_vma_rotate(void *arg)
> +{
> +	struct drm_i915_private *i915 = arg;
> +	struct drm_i915_gem_object *obj;
> +	const struct intel_rotation_plane_info planes[] = {
> +		{ .width = 1, .height = 1, .stride = 1 },
> +		{ .width = 3, .height = 5, .stride = 4 },
> +		{ .width = 5, .height = 3, .stride = 7 },
> +		{ .width = 6, .height = 4, .stride = 6 },

4x6 stride 4 could be added if you were going for all combinations of 
wide/tall, equal stride and wider stride.

> +		{ }
> +	}, *a, *b;
> +	const unsigned int max_pages = 64;
> +	int err = -ENOMEM;
> +
> +	/* Create VMA for many different combinations of planes and check
> +	 * that the page layout within the rotated VMA match our expectations.
> +	 */
> +
> +	obj = i915_gem_object_create_internal(i915, max_pages * PAGE_SIZE);
> +	if (IS_ERR(obj))
> +		goto err;
> +
> +	for (a = planes; a->width; a++) {
> +		for (b = planes + ARRAY_SIZE(planes); b-- != planes; ) {
> +			struct i915_ggtt_view view;
> +			struct scatterlist *sg;
> +			unsigned int n, max_offset;
> +
> +			max_offset = max(a->stride * a->height,
> +					 b->stride * b->height);

It shouldn't be min?

> +			GEM_BUG_ON(max_offset >= max_pages);
> +			max_offset = max_pages - max_offset;
> +
> +			view.type = I915_GGTT_VIEW_ROTATED;
> +			view.rotated.plane[0] = *a;
> +			view.rotated.plane[1] = *b;

Single plane tests could be added as well.

> +
> +			for_each_prime_number_from(view.rotated.plane[0].offset, 0, max_offset) {
> +				for_each_prime_number_from(view.rotated.plane[1].offset, 0, max_offset) {

I would try all offsets here and not only primes since it is super fast 
and more importantly more realistic.

> +					struct i915_address_space *vm =
> +						&i915->ggtt.base;
> +					struct i915_vma *vma;
> +
> +					vma = i915_vma_instance(obj, vm, &view);
> +					if (IS_ERR(vma)) {
> +						err = PTR_ERR(vma);
> +						goto err_object;
> +					}
> +
> +					if (!i915_vma_is_ggtt(vma) ||
> +					    vma->vm != vm) {
> +						pr_err("VMA is not in the GGTT!\n");
> +						err = -EINVAL;
> +						goto err_object;
> +					}
> +
> +					if (memcmp(&vma->ggtt_view, &view, sizeof(view))) {

Just because rotation is the largest view! :) Need to use the "type" here.

> +						pr_err("VMA mismatch upon creation!\n");
> +						err = -EINVAL;
> +						goto err_object;
> +					}
> +
> +					if (i915_vma_compare(vma,
> +							     vma->vm,
> +							     &vma->ggtt_view)) {
> +						pr_err("VMA compmare failed with itself\n");

typo in compare

> +						err = -EINVAL;
> +						goto err_object;
> +					}
> +
> +					err = i915_vma_pin(vma, 0, 0, PIN_GLOBAL);
> +					if (err) {
> +						pr_err("Failed to pin VMA, err=%d\n", err);
> +						goto err_object;
> +					}
> +
> +					if (vma->size != rotated_size(a, b) * PAGE_SIZE) {
> +						pr_err("VMA is wrong size, expected %lu, found %llu\n",
> +						       PAGE_SIZE * rotated_size(a, b), vma->size);
> +						err = -EINVAL;
> +						goto err_object;
> +					}
> +
> +					if (vma->node.size < vma->size) {
> +						pr_err("VMA binding too small, expected %llu, found %llu\n",
> +						       vma->size, vma->node.size);
> +						err = -EINVAL;
> +						goto err_object;
> +					}
> +
> +					if (vma->pages == obj->mm.pages) {
> +						pr_err("VMA using unrotated object pages!\n");
> +						err = -EINVAL;
> +						goto err_object;
> +					}
> +
> +					sg = vma->pages->sgl;
> +					for (n = 0; n < ARRAY_SIZE(view.rotated.plane); n++) {
> +						sg = assert_rotated(obj, &view.rotated, n, sg);
> +						if (IS_ERR(sg)) {
> +							pr_err("Inconsistent VMA pages for plane %d: [(%d, %d, %d, %d), (%d, %d, %d, %d)]\n", n,
> +							view.rotated.plane[0].width,
> +							view.rotated.plane[0].height,
> +							view.rotated.plane[0].stride,
> +							view.rotated.plane[0].offset,
> +							view.rotated.plane[1].width,
> +							view.rotated.plane[1].height,
> +							view.rotated.plane[1].stride,
> +							view.rotated.plane[1].offset);
> +							err = -EINVAL;
> +							goto err_object;
> +						}
> +					}
> +
> +					i915_vma_unpin(vma);
> +				}
> +			}
> +		}
> +	}
> +
> +err_object:
> +	i915_gem_object_put(obj);
> +err:
> +	return err;
> +}
> +
>  int i915_vma_mock_selftests(void)
>  {
>  	static const struct i915_subtest tests[] = {
>  		SUBTEST(igt_vma_create),
>  		SUBTEST(igt_vma_pin1),
> +		SUBTEST(igt_vma_rotate),
>  	};
>  	struct drm_i915_private *i915;
>  	int err;
>

Regards,

Tvrtko