drm/i915: Decouple SKL stride units from intel_fb_stride_alignment()

In the future framebuffer stride alignment requirements won't exactly
match the units in which skl+ plane stride is specified. So extract
the code for the skl+ stuff into a separate helper.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180925193714.25280-3-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 14cca56..6fce44b 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3475,6 +3475,21 @@ static void skl_detach_scalers(const struct intel_crtc_state *crtc_state)
        }
 }
 
+static unsigned int skl_plane_stride_mult(const struct drm_framebuffer *fb,
+                                         int color_plane, unsigned int rotation)
+{
+       /*
+        * The stride is either expressed as a multiple of 64 bytes chunks for
+        * linear buffers or in number of tiles for tiled buffers.
+        */
+       if (fb->modifier == DRM_FORMAT_MOD_LINEAR)
+               return 64;
+       else if (drm_rotation_90_or_270(rotation))
+               return intel_tile_height(fb, color_plane);
+       else
+               return intel_tile_width_bytes(fb, color_plane);
+}
+
 u32 skl_plane_stride(const struct intel_plane_state *plane_state,
                     int color_plane)
 {
@@ -3485,16 +3500,7 @@ u32 skl_plane_stride(const struct intel_plane_state *plane_state,
        if (color_plane >= fb->format->num_planes)
                return 0;
 
-       /*
-        * The stride is either expressed as a multiple of 64 bytes chunks for
-        * linear buffers or in number of tiles for tiled buffers.
-        */
-       if (drm_rotation_90_or_270(rotation))
-               stride /= intel_tile_height(fb, color_plane);
-       else
-               stride /= intel_fb_stride_alignment(fb, color_plane);
-
-       return stride;
+       return stride / skl_plane_stride_mult(fb, color_plane, rotation);
 }
 
 static u32 skl_plane_ctl_format(uint32_t pixel_format)
@@ -8967,7 +8973,7 @@ skylake_get_initial_plane_config(struct intel_crtc *crtc,
        fb->width = ((val >> 0) & 0x1fff) + 1;
 
        val = I915_READ(PLANE_STRIDE(pipe, plane_id));
-       stride_mult = intel_fb_stride_alignment(fb, 0);
+       stride_mult = skl_plane_stride_mult(fb, 0, DRM_MODE_ROTATE_0);
        fb->pitches[0] = (val & 0x3ff) * stride_mult;
 
        aligned_height = intel_fb_align_height(fb, 0, fb->height);