drm/vmwgfx: Start diffing new mob cursors against old ones

Avoid making the SVGA device do extra work if the new cursor image
matches the old one.

Signed-off-by: Michael Banack <banackm@vmware.com>
Signed-off-by: Zack Rusin <zackr@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-8-zack@kde.org

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
index 07d55d610e4c1377412d59b9f4f0ce10cb138423..464d7c8cd1d62c9989797bede15b762ef2e1d7b0 100644 (file)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
@@ -52,11 +52,9 @@ void vmw_du_cleanup(struct vmw_display_unit *du)
  * Display Unit Cursor functions
  */
 
-static void vmw_cursor_update_mob(struct vmw_private *dev_priv,
-                                 struct vmw_plane_state *vps,
-                                 u32 *image, u32 width, u32 height,
-                                 u32 hotspotX, u32 hotspotY);
 static int vmw_du_cursor_plane_unmap_cm(struct vmw_plane_state *vps);
+static void vmw_cursor_write_mobid(struct vmw_private *dev_priv,
+                                  struct vmw_plane_state *vps);
 
 struct vmw_svga_fifo_cmd_define_cursor {
        u32 cmd;
@@ -120,9 +118,7 @@ static void vmw_cursor_update_image(struct vmw_private *dev_priv,
                                    u32 hotspotX, u32 hotspotY)
 {
        if (vps->cursor.bo != NULL)
-               vmw_cursor_update_mob(dev_priv, vps, image,
-                                     width, height,
-                                     hotspotX, hotspotY);
+               vmw_cursor_write_mobid(dev_priv, vps);
        else
                vmw_send_define_cursor_cmd(dev_priv, image, width, height,
                                           hotspotX, hotspotY);
@@ -167,6 +163,21 @@ static void vmw_cursor_update_mob(struct vmw_private *dev_priv,
        alpha_header->height = height;
 
        memcpy(header + 1, image, image_size);
+}
+
+
+/**
+ * vmw_cursor_write_mobid - Update cursor via CursorMob mechanism
+ *
+ * Called from inside vmw_du_cursor_plane_atomic_update to actually
+ * make the cursor-image live.
+ *
+ * @dev_priv: device to work with
+ * @vps: DRM plane_state
+ */
+static void vmw_cursor_write_mobid(struct vmw_private *dev_priv,
+                                  struct vmw_plane_state *vps)
+{
        vmw_write(dev_priv, SVGA_REG_CURSOR_MOBID,
                  vps->cursor.bo->resource->start);
 }
@@ -176,6 +187,39 @@ static u32 vmw_du_cursor_mob_size(u32 w, u32 h)
        return w * h * sizeof(u32) + sizeof(SVGAGBCursorHeader);
 }
 
+
+static bool vmw_du_cursor_plane_mob_has_changed(struct vmw_plane_state *old_vps,
+                                               struct vmw_plane_state *new_vps)
+{
+       void *old_mob;
+       void *new_mob;
+       bool dummy;
+       u32 size;
+
+       // If either of them aren't using CursorMobs, assume changed.
+       if (old_vps->cursor.bo == NULL || new_vps->cursor.bo == NULL)
+               return true;
+
+       // If either of them failed to map, assume changed.
+       if (!old_vps->cursor.mapped || !new_vps->cursor.mapped)
+               return true;
+
+       if (old_vps->base.crtc_w != new_vps->base.crtc_w ||
+           old_vps->base.crtc_h != new_vps->base.crtc_h)
+           return true;
+
+       size = vmw_du_cursor_mob_size(new_vps->base.crtc_w,
+                                     new_vps->base.crtc_h);
+
+       old_mob = ttm_kmap_obj_virtual(&old_vps->cursor.map, &dummy);
+       new_mob = ttm_kmap_obj_virtual(&new_vps->cursor.map, &dummy);
+
+       if (memcmp(old_mob, new_mob, size) != 0)
+               return true;
+
+       return false;
+}
+
 static void vmw_du_destroy_cursor_mob(struct ttm_buffer_object **bo)
 {
        if (*bo == NULL)
@@ -716,9 +760,10 @@ vmw_du_cursor_plane_atomic_update(struct drm_plane *plane,
        struct vmw_private *dev_priv = vmw_priv(crtc->dev);
        struct vmw_display_unit *du = vmw_crtc_to_du(crtc);
        struct vmw_plane_state *vps = vmw_plane_state_to_vps(new_state);
+       struct vmw_plane_state *old_vps = vmw_plane_state_to_vps(old_state);
        s32 hotspot_x, hotspot_y;
-       void *virtual;
        bool dummy;
+       void *image;
 
        hotspot_x = du->hotspot_x;
        hotspot_y = du->hotspot_y;
@@ -738,23 +783,32 @@ vmw_du_cursor_plane_atomic_update(struct drm_plane *plane,
 
        if (vps->surf != NULL) {
                du->cursor_age = du->cursor_surface->snooper.age;
+               image = vps->surf->snooper.image;
+       } else
+               image = ttm_kmap_obj_virtual(&vps->bo->map, &dummy);
 
-               vmw_cursor_update_image(dev_priv, vps,
-                                       vps->surf->snooper.image,
+       if (vps->cursor.bo != NULL)
+               vmw_cursor_update_mob(dev_priv, vps, image,
+                                     new_state->crtc_w,
+                                     new_state->crtc_h,
+                                     hotspot_x, hotspot_y);
+
+       if (!vmw_du_cursor_plane_mob_has_changed(old_vps, vps)) {
+               /*
+                * If it hasn't changed, avoid making the device do extra
+                * work by keeping the old mob active.
+                */
+               struct vmw_cursor_plane_state tmp = old_vps->cursor;
+               old_vps->cursor = vps->cursor;
+               vps->cursor = tmp;
+       } else if (image != NULL)
+               vmw_cursor_update_image(dev_priv, vps, image,
                                        new_state->crtc_w,
                                        new_state->crtc_h,
                                        hotspot_x, hotspot_y);
-       } else {
 
-               virtual = ttm_kmap_obj_virtual(&vps->bo->map, &dummy);
-               if (virtual) {
-                       vmw_cursor_update_image(dev_priv, vps, virtual,
-                                               new_state->crtc_w,
-                                               new_state->crtc_h,
-                                               hotspot_x, hotspot_y);
-                       atomic_dec(&vps->bo->base_mapped_count);
-               }
-       }
+       if (image != NULL && vps->bo != NULL)
+               atomic_dec(&vps->bo->base_mapped_count);
 
        du->cursor_x = new_state->crtc_x + du->set_gui_x;
        du->cursor_y = new_state->crtc_y + du->set_gui_y;
@@ -1074,7 +1128,6 @@ vmw_du_plane_destroy_state(struct drm_plane *plane,
 {
        struct vmw_plane_state *vps = vmw_plane_state_to_vps(state);
 
-
        /* Should have been freed by cleanup_fb */
        if (vps->surf)
                vmw_surface_unreference(&vps->surf);

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.h b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.h
index a9bcc91f978b299b2bb5a6755cfc0006254b14ea..fb4c9f9e349329075d414d184695ee0a91248bd4 100644 (file)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.h
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.h
@@ -272,6 +272,12 @@ struct vmw_crtc_state {
        struct drm_crtc_state base;
 };
 
+struct vmw_cursor_plane_state {
+       struct ttm_buffer_object *bo;
+       struct ttm_bo_kmap_obj map;
+       bool mapped;
+};
+
 /**
  * Derived class for plane state object
  *
@@ -295,11 +301,7 @@ struct vmw_plane_state {
        /* For CPU Blit */
        unsigned int cpp;
 
-       struct {
-               struct ttm_buffer_object *bo;
-               struct ttm_bo_kmap_obj map;
-               bool mapped;
-       } cursor;
+       struct vmw_cursor_plane_state cursor;
 };