drm/i915: Exercise manipulate of single pages in the GGTT

Move a single page of an object around within the GGTT and check
coherency of writes and reads.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170213171558.20942-45-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
index 5caa515..36e5cb5 100644 (file)
--- a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
@@ -903,6 +903,96 @@ static int igt_ggtt_lowlevel(void *arg)
        return exercise_ggtt(arg, lowlevel_hole);
 }
 
+static int igt_ggtt_page(void *arg)
+{
+       const unsigned int count = PAGE_SIZE/sizeof(u32);
+       I915_RND_STATE(prng);
+       struct drm_i915_private *i915 = arg;
+       struct i915_ggtt *ggtt = &i915->ggtt;
+       struct drm_i915_gem_object *obj;
+       struct drm_mm_node tmp;
+       unsigned int *order, n;
+       int err;
+
+       mutex_lock(&i915->drm.struct_mutex);
+
+       obj = i915_gem_object_create_internal(i915, PAGE_SIZE);
+       if (IS_ERR(obj)) {
+               err = PTR_ERR(obj);
+               goto out_unlock;
+       }
+
+       err = i915_gem_object_pin_pages(obj);
+       if (err)
+               goto out_free;
+
+       memset(&tmp, 0, sizeof(tmp));
+       err = drm_mm_insert_node_in_range(&ggtt->base.mm, &tmp,
+                                         1024 * PAGE_SIZE, 0,
+                                         I915_COLOR_UNEVICTABLE,
+                                         0, ggtt->mappable_end,
+                                         DRM_MM_INSERT_LOW);
+       if (err)
+               goto out_unpin;
+
+       order = i915_random_order(count, &prng);
+       if (!order) {
+               err = -ENOMEM;
+               goto out_remove;
+       }
+
+       for (n = 0; n < count; n++) {
+               u64 offset = tmp.start + order[n] * PAGE_SIZE;
+               u32 __iomem *vaddr;
+
+               ggtt->base.insert_page(&ggtt->base,
+                                      i915_gem_object_get_dma_address(obj, 0),
+                                      offset, I915_CACHE_NONE, 0);
+
+               vaddr = io_mapping_map_atomic_wc(&ggtt->mappable, offset);
+               iowrite32(n, vaddr + n);
+               io_mapping_unmap_atomic(vaddr);
+
+               wmb();
+               ggtt->base.clear_range(&ggtt->base, offset, PAGE_SIZE);
+       }
+
+       i915_random_reorder(order, count, &prng);
+       for (n = 0; n < count; n++) {
+               u64 offset = tmp.start + order[n] * PAGE_SIZE;
+               u32 __iomem *vaddr;
+               u32 val;
+
+               ggtt->base.insert_page(&ggtt->base,
+                                      i915_gem_object_get_dma_address(obj, 0),
+                                      offset, I915_CACHE_NONE, 0);
+
+               vaddr = io_mapping_map_atomic_wc(&ggtt->mappable, offset);
+               val = ioread32(vaddr + n);
+               io_mapping_unmap_atomic(vaddr);
+
+               ggtt->base.clear_range(&ggtt->base, offset, PAGE_SIZE);
+
+               if (val != n) {
+                       pr_err("insert page failed: found %d, expected %d\n",
+                              val, n);
+                       err = -EINVAL;
+                       break;
+               }
+       }
+
+       kfree(order);
+out_remove:
+       drm_mm_remove_node(&tmp);
+out_unpin:
+       i915_gem_object_unpin_pages(obj);
+out_free:
+       i915_gem_object_put(obj);
+out_unlock:
+       mutex_unlock(&i915->drm.struct_mutex);
+       return err;
+}
+
 static void track_vma_bind(struct i915_vma *vma)
 {
        struct drm_i915_gem_object *obj = vma->obj;
@@ -1360,6 +1450,7 @@ int i915_gem_gtt_live_selftests(struct drm_i915_private *i915)
                SUBTEST(igt_ggtt_drunk),
                SUBTEST(igt_ggtt_walk),
                SUBTEST(igt_ggtt_fill),
+               SUBTEST(igt_ggtt_page),
        };
 
        GEM_BUG_ON(offset_in_page(i915->ggtt.base.total));