1 files changed, 191 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 7f6141d9a06d..0f32f6498ad3 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -117,6 +117,197 @@ done:
         dev_priv->pch_pf_size = (width << 16) | height;
 }
 
+static void
+centre_horizontally(struct drm_display_mode *mode,
+                    int width)
+{
+        u32 border, sync_pos, blank_width, sync_width;
+
+        /* keep the hsync and hblank widths constant */
+        sync_width = mode->crtc_hsync_end - mode->crtc_hsync_start;
+        blank_width = mode->crtc_hblank_end - mode->crtc_hblank_start;
+        sync_pos = (blank_width - sync_width + 1) / 2;
+
+        border = (mode->hdisplay - width + 1) / 2;
+        border += border & 1; /* make the border even */
+
+        mode->crtc_hdisplay = width;
+        mode->crtc_hblank_start = width + border;
+        mode->crtc_hblank_end = mode->crtc_hblank_start + blank_width;
+
+        mode->crtc_hsync_start = mode->crtc_hblank_start + sync_pos;
+        mode->crtc_hsync_end = mode->crtc_hsync_start + sync_width;
+}
+
+static void
+centre_vertically(struct drm_display_mode *mode,
+                  int height)
+{
+        u32 border, sync_pos, blank_width, sync_width;
+
+        /* keep the vsync and vblank widths constant */
+        sync_width = mode->crtc_vsync_end - mode->crtc_vsync_start;
+        blank_width = mode->crtc_vblank_end - mode->crtc_vblank_start;
+        sync_pos = (blank_width - sync_width + 1) / 2;
+
+        border = (mode->vdisplay - height + 1) / 2;
+
+        mode->crtc_vdisplay = height;
+        mode->crtc_vblank_start = height + border;
+        mode->crtc_vblank_end = mode->crtc_vblank_start + blank_width;
+
+        mode->crtc_vsync_start = mode->crtc_vblank_start + sync_pos;
+        mode->crtc_vsync_end = mode->crtc_vsync_start + sync_width;
+}
+
+static inline u32 panel_fitter_scaling(u32 source, u32 target)
+{
+        /*
+         * Floating point operation is not supported. So the FACTOR
+         * is defined, which can avoid the floating point computation
+         * when calculating the panel ratio.
+         */
+#define ACCURACY 12
+#define FACTOR (1 << ACCURACY)
+        u32 ratio = source * FACTOR / target;
+        return (FACTOR * ratio + FACTOR/2) / FACTOR;
+}
+
+void intel_gmch_panel_fitting(struct intel_crtc *intel_crtc,
+                              struct intel_crtc_config *pipe_config,
+                              int fitting_mode)
+{
+        struct drm_device *dev = intel_crtc->base.dev;
+        struct drm_i915_private *dev_priv = dev->dev_private;
+        u32 pfit_control = 0, pfit_pgm_ratios = 0, border = 0;
+        struct drm_display_mode *mode, *adjusted_mode;
+
+        mode = &pipe_config->requested_mode;
+        adjusted_mode = &pipe_config->adjusted_mode;
+
+        /* Native modes don't need fitting */
+        if (adjusted_mode->hdisplay == mode->hdisplay &&
+            adjusted_mode->vdisplay == mode->vdisplay)
+                goto out;
+
+        switch (fitting_mode) {
+        case DRM_MODE_SCALE_CENTER:
+                /*
+                 * For centered modes, we have to calculate border widths &
+                 * heights and modify the values programmed into the CRTC.
+                 */
+                centre_horizontally(adjusted_mode, mode->hdisplay);
+                centre_vertically(adjusted_mode, mode->vdisplay);
+                border = LVDS_BORDER_ENABLE;
+                break;
+        case DRM_MODE_SCALE_ASPECT:
+                /* Scale but preserve the aspect ratio */
+                if (INTEL_INFO(dev)->gen >= 4) {
+                        u32 scaled_width = adjusted_mode->hdisplay *
+                                mode->vdisplay;
+                        u32 scaled_height = mode->hdisplay *
+                                adjusted_mode->vdisplay;
+
+                        /* 965+ is easy, it does everything in hw */
+                        if (scaled_width > scaled_height)
+                                pfit_control |= PFIT_ENABLE |
+                                        PFIT_SCALING_PILLAR;
+                        else if (scaled_width < scaled_height)
+                                pfit_control |= PFIT_ENABLE |
+                                        PFIT_SCALING_LETTER;
+                        else if (adjusted_mode->hdisplay != mode->hdisplay)
+                                pfit_control |= PFIT_ENABLE | PFIT_SCALING_AUTO;
+                } else {
+                        u32 scaled_width = adjusted_mode->hdisplay *
+                                mode->vdisplay;
+                        u32 scaled_height = mode->hdisplay *
+                                adjusted_mode->vdisplay;
+                        /*
+                         * For earlier chips we have to calculate the scaling
+                         * ratio by hand and program it into the
+                         * PFIT_PGM_RATIO register
+                         */
+                        if (scaled_width > scaled_height) { /* pillar */
+                                centre_horizontally(adjusted_mode,
+                                                    scaled_height /
+                                                    mode->vdisplay);
+
+                                border = LVDS_BORDER_ENABLE;
+                                if (mode->vdisplay != adjusted_mode->vdisplay) {
+                                        u32 bits = panel_fitter_scaling(mode->vdisplay, adjusted_mode->vdisplay);
+                                        pfit_pgm_ratios |= (bits << PFIT_HORIZ_SCALE_SHIFT |
+                                                            bits << PFIT_VERT_SCALE_SHIFT);
+                                        pfit_control |= (PFIT_ENABLE |
+                                                         VERT_INTERP_BILINEAR |
+                                                         HORIZ_INTERP_BILINEAR);
+                                }
+                        } else if (scaled_width < scaled_height) { /* letter */
+                                centre_vertically(adjusted_mode,
+                                                  scaled_width /
+                                                  mode->hdisplay);
+
+                                border = LVDS_BORDER_ENABLE;
+                                if (mode->hdisplay != adjusted_mode->hdisplay) {
+                                        u32 bits = panel_fitter_scaling(mode->hdisplay, adjusted_mode->hdisplay);
+                                        pfit_pgm_ratios |= (bits << PFIT_HORIZ_SCALE_SHIFT |
+                                                            bits << PFIT_VERT_SCALE_SHIFT);
+                                        pfit_control |= (PFIT_ENABLE |
+                                                         VERT_INTERP_BILINEAR |
+                                                         HORIZ_INTERP_BILINEAR);
+                                }
+                        } else {
+                                /* Aspects match, Let hw scale both directions */
+                                pfit_control |= (PFIT_ENABLE |
+                                                 VERT_AUTO_SCALE | HORIZ_AUTO_SCALE |
+                                                 VERT_INTERP_BILINEAR |
+                                                 HORIZ_INTERP_BILINEAR);
+                        }
+                }
+                break;
+        default:
+        case DRM_MODE_SCALE_FULLSCREEN:
+                /*
+                 * Full scaling, even if it changes the aspect ratio.
+                 * Fortunately this is all done for us in hw.
+                 */
+                if (mode->vdisplay != adjusted_mode->vdisplay ||
+                    mode->hdisplay != adjusted_mode->hdisplay) {
+                        pfit_control |= PFIT_ENABLE;
+                        if (INTEL_INFO(dev)->gen >= 4)
+                                pfit_control |= PFIT_SCALING_AUTO;
+                        else
+                                pfit_control |= (VERT_AUTO_SCALE |
+                                                 VERT_INTERP_BILINEAR |
+                                                 HORIZ_AUTO_SCALE |
+                                                 HORIZ_INTERP_BILINEAR);
+                }
+                break;
+        }
+
+        /* 965+ wants fuzzy fitting */
+        /* FIXME: handle multiple panels by failing gracefully */
+        if (INTEL_INFO(dev)->gen >= 4)
+                pfit_control |= ((intel_crtc->pipe << PFIT_PIPE_SHIFT) |
+                                 PFIT_FILTER_FUZZY);
+
+out:
+        if ((pfit_control & PFIT_ENABLE) == 0) {
+                pfit_control = 0;
+                pfit_pgm_ratios = 0;
+        }
+
+        /* Make sure pre-965 set dither correctly for 18bpp panels. */
+        if (INTEL_INFO(dev)->gen < 4 && pipe_config->pipe_bpp == 18)
+                pfit_control |= PANEL_8TO6_DITHER_ENABLE;
+
+        if (pfit_control != pipe_config->pfit_control ||
+            pfit_pgm_ratios != pipe_config->pfit_pgm_ratios) {
+                pipe_config->pfit_control = pfit_control;
+                pipe_config->pfit_pgm_ratios = pfit_pgm_ratios;
+        }
+        dev_priv->lvds_border_bits = border;
+}
+
 static int is_backlight_combination_mode(struct drm_device *dev)
 {
         struct drm_i915_private *dev_priv = dev->dev_private;