drm/i915/skl: Support secondary (rotated) frame buffer mapping

90/270 rotated scanout needs a rotated GTT view of the framebuffer.

This is put in a separate VMA with a dedicated ggtt view and wired such that
it is created when a framebuffer is pinned to a 90/270 rotated plane.

Rotation is only possible with Yb/Yf buffers and error is propagated to
user space in case of a mismatch.

Special rotated page view is constructed at the VMA creation time by
borrowing the DMA addresses from obj->pages.

v2:
    * Do not bother with pages for rotated sg list, just populate the DMA
      addresses. (Daniel Vetter)
    * Checkpatch cleanup.

v3:
    * Rebased on top of new plane handling (create rotated mapping when
      setting the rotation property).
    * Unpin rotated VMA on unpinning from display plane.
    * Simplify rotation check using bitwise AND. (Chris Wilson)

v4:
    * Fix unpinning of optional rotated mapping so it is really considered
      to be optional.

v5:
   * Rebased for fb modifier changes.
   * Rebased for atomic commit.
   * Only pin needed view for display. (Ville Syrjälä, Daniel Vetter)

v6:
   * Rebased after preparatory work has been extracted out. (Daniel Vetter)

v7:
   * Slightly simplified tiling geometry calculation.
   * Moved rotated GGTT view implementation into i915_gem_gtt.c (Daniel Vetter)

v8:
   * Do not use i915_gem_obj_size to get object size since that actually
     returns the size of an VMA which may not exist.
   * Rebased for ggtt view changes.

v9:
   * Rebased after code review changes on the preceding patches.
   * Tidy function definitions. (Joonas Lahtinen)

For: VIZ-4726
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Michel Thierry <michel.thierry@intel.com> (v4)
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 31978b0..538cae2 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -3908,7 +3908,9 @@ i915_gem_object_pin_to_display_plane(struct drm_i915_gem_object *obj,
         * (e.g. libkms for the bootup splash), we have to ensure that we
         * always use map_and_fenceable for all scanout buffers.
         */
-       ret = i915_gem_object_ggtt_pin(obj, view, alignment, PIN_MAPPABLE);
+       ret = i915_gem_object_ggtt_pin(obj, view, alignment,
+                                      view->type == I915_GGTT_VIEW_NORMAL ?
+                                      PIN_MAPPABLE : 0);
        if (ret)
                goto err_unpin_display;
 

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 645c363..fc56c11 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -2500,15 +2500,119 @@ i915_gem_obj_lookup_or_create_ggtt_vma(struct drm_i915_gem_object *obj,
 
 }
 
+static void
+rotate_pages(dma_addr_t *in, unsigned int width, unsigned int height,
+            struct sg_table *st)
+{
+       unsigned int column, row;
+       unsigned int src_idx;
+       struct scatterlist *sg = st->sgl;
+
+       st->nents = 0;
+
+       for (column = 0; column < width; column++) {
+               src_idx = width * (height - 1) + column;
+               for (row = 0; row < height; row++) {
+                       st->nents++;
+                       /* 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.
+                        */
+                       sg_set_page(sg, NULL, PAGE_SIZE, 0);
+                       sg_dma_address(sg) = in[src_idx];
+                       sg_dma_len(sg) = PAGE_SIZE;
+                       sg = sg_next(sg);
+                       src_idx -= width;
+               }
+       }
+}
+
+static struct sg_table *
+intel_rotate_fb_obj_pages(struct i915_ggtt_view *ggtt_view,
+                         struct drm_i915_gem_object *obj)
+{
+       struct drm_device *dev = obj->base.dev;
+       struct intel_rotation_info *rot_info = &ggtt_view->rotation_info;
+       unsigned long size, pages, rot_pages;
+       struct sg_page_iter sg_iter;
+       unsigned long i;
+       dma_addr_t *page_addr_list;
+       struct sg_table *st;
+       unsigned int tile_pitch, tile_height;
+       unsigned int width_pages, height_pages;
+       int ret = ENOMEM;
+
+       pages = obj->base.size / PAGE_SIZE;
+
+       /* Calculate tiling geometry. */
+       tile_height = intel_tile_height(dev, rot_info->pixel_format,
+                                       rot_info->fb_modifier);
+       tile_pitch = PAGE_SIZE / tile_height;
+       width_pages = DIV_ROUND_UP(rot_info->pitch, tile_pitch);
+       height_pages = DIV_ROUND_UP(rot_info->height, tile_height);
+       rot_pages = width_pages * height_pages;
+       size = rot_pages * PAGE_SIZE;
+
+       /* Allocate a temporary list of source pages for random access. */
+       page_addr_list = drm_malloc_ab(pages, sizeof(dma_addr_t));
+       if (!page_addr_list)
+               return ERR_PTR(ret);
+
+       /* Allocate target SG list. */
+       st = kmalloc(sizeof(*st), GFP_KERNEL);
+       if (!st)
+               goto err_st_alloc;
+
+       ret = sg_alloc_table(st, rot_pages, GFP_KERNEL);
+       if (ret)
+               goto err_sg_alloc;
+
+       /* Populate source page list from the object. */
+       i = 0;
+       for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, 0) {
+               page_addr_list[i] = sg_page_iter_dma_address(&sg_iter);
+               i++;
+       }
+
+       /* Rotate the pages. */
+       rotate_pages(page_addr_list, width_pages, height_pages, st);
+
+       DRM_DEBUG_KMS(
+                     "Created rotated page mapping for object size %lu (pitch=%u, height=%u, pixel_format=0x%x, %ux%u tiles, %lu pages).\n",
+                     size, rot_info->pitch, rot_info->height,
+                     rot_info->pixel_format, width_pages, height_pages,
+                     rot_pages);
+
+       drm_free_large(page_addr_list);
+
+       return st;
+
+err_sg_alloc:
+       kfree(st);
+err_st_alloc:
+       drm_free_large(page_addr_list);
+
+       DRM_DEBUG_KMS(
+                     "Failed to create rotated mapping for object size %lu! (%d) (pitch=%u, height=%u, pixel_format=0x%x, %ux%u tiles, %lu pages)\n",
+                     size, ret, rot_info->pitch, rot_info->height,
+                     rot_info->pixel_format, width_pages, height_pages,
+                     rot_pages);
+       return ERR_PTR(ret);
+}
 
-static inline
-int i915_get_ggtt_vma_pages(struct i915_vma *vma)
+static inline int
+i915_get_ggtt_vma_pages(struct i915_vma *vma)
 {
+       int ret = 0;
+
        if (vma->ggtt_view.pages)
                return 0;
 
        if (vma->ggtt_view.type == I915_GGTT_VIEW_NORMAL)
                vma->ggtt_view.pages = vma->obj->pages;
+       else if (vma->ggtt_view.type == I915_GGTT_VIEW_ROTATED)
+               vma->ggtt_view.pages =
+                       intel_rotate_fb_obj_pages(&vma->ggtt_view, vma->obj);
        else
                WARN_ONCE(1, "GGTT view %u not implemented!\n",
                          vma->ggtt_view.type);
@@ -2516,10 +2620,15 @@ int i915_get_ggtt_vma_pages(struct i915_vma *vma)
        if (!vma->ggtt_view.pages) {
                DRM_ERROR("Failed to get pages for GGTT view type %u!\n",
                          vma->ggtt_view.type);
-               return -EINVAL;
+               ret = -EINVAL;
+       } else if (IS_ERR(vma->ggtt_view.pages)) {
+               ret = PTR_ERR(vma->ggtt_view.pages);
+               vma->ggtt_view.pages = NULL;
+               DRM_ERROR("Failed to get pages for VMA view type %u (%d)!\n",
+                         vma->ggtt_view.type, ret);
        }
 
-       return 0;
+       return ret;
 }
 
 /**

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index 75e29f7..0dad426 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -117,12 +117,24 @@ typedef uint64_t gen8_pde_t;
 
 enum i915_ggtt_view_type {
        I915_GGTT_VIEW_NORMAL = 0,
+       I915_GGTT_VIEW_ROTATED
+};
+
+struct intel_rotation_info {
+       unsigned int height;
+       unsigned int pitch;
+       uint32_t pixel_format;
+       uint64_t fb_modifier;
 };
 
 struct i915_ggtt_view {
        enum i915_ggtt_view_type type;
 
        struct sg_table *pages;
+
+       union {
+               struct intel_rotation_info rotation_info;
+       };
 };
 
 extern const struct i915_ggtt_view i915_ggtt_view_normal;

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index d3fa09b..f605b09 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2233,7 +2233,7 @@ static bool need_vtd_wa(struct drm_device *dev)
        return false;
 }
 
-static unsigned int
+unsigned int
 intel_tile_height(struct drm_device *dev, uint32_t pixel_format,
                  uint64_t fb_format_modifier)
 {
@@ -2292,8 +2292,33 @@ static int
 intel_fill_fb_ggtt_view(struct i915_ggtt_view *view, struct drm_framebuffer *fb,
                        const struct drm_plane_state *plane_state)
 {
+       struct intel_rotation_info *info = &view->rotation_info;
+       static const struct i915_ggtt_view rotated_view =
+                               { .type = I915_GGTT_VIEW_ROTATED };
+
        *view = i915_ggtt_view_normal;
 
+       if (!plane_state)
+               return 0;
+
+       if (!(plane_state->rotation &
+           (BIT(DRM_ROTATE_90) | BIT(DRM_ROTATE_270))))
+               return 0;
+
+       *view = rotated_view;
+
+       info->height = fb->height;
+       info->pixel_format = fb->pixel_format;
+       info->pitch = fb->pitches[0];
+       info->fb_modifier = fb->modifier[0];
+
+       if (!(info->fb_modifier == I915_FORMAT_MOD_Y_TILED ||
+             info->fb_modifier == I915_FORMAT_MOD_Yf_TILED)) {
+               DRM_DEBUG_KMS(
+                             "Y or Yf tiling is needed for 90/270 rotation!\n");
+               return -EINVAL;
+       }
+
        return 0;
 }
 

diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index a0df556..cb00bd0 100644 (file)
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -984,6 +984,10 @@ int intel_plane_atomic_set_property(struct drm_plane *plane,
                                    struct drm_property *property,
                                    uint64_t val);
 
+unsigned int
+intel_tile_height(struct drm_device *dev, uint32_t pixel_format,
+                 uint64_t fb_format_modifier);
+
 /* shared dpll functions */
 struct intel_shared_dpll *intel_crtc_to_shared_dpll(struct intel_crtc *crtc);
 void assert_shared_dpll(struct drm_i915_private *dev_priv,