drm/i915/skl: Extract tile height code into a helper function

It will be used in a later patch and also convert all height parameters
from int to unsigned int.

v2: Rebased for fb modifiers.
v3: Fixed v2 rebase.
v4:
   * Height should be unsigned int.
   * Make it take pixel_format for consistency and simplicity.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Michel Thierry <michel.thierry@intel.com> (v1)
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> (v4)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -2233,13 +2233,12 @@ static bool need_vtd_wa(struct drm_device *dev)
 	return false;
 }
 
-int
-intel_fb_align_height(struct drm_device *dev, int height,
-		      uint32_t pixel_format,
-		      uint64_t fb_format_modifier)
+static unsigned int
+intel_tile_height(struct drm_device *dev, uint32_t pixel_format,
+		  uint64_t fb_format_modifier)
 {
-	int tile_height;
-	uint32_t bits_per_pixel;
+	unsigned int tile_height;
+	uint32_t pixel_bytes;
 
 	switch (fb_format_modifier) {
 	case DRM_FORMAT_MOD_NONE:
@@ -2252,20 +2251,20 @@ intel_fb_align_height(struct drm_device *dev, int height,
 		tile_height = 32;
 		break;
 	case I915_FORMAT_MOD_Yf_TILED:
-		bits_per_pixel = drm_format_plane_cpp(pixel_format, 0) * 8;
-		switch (bits_per_pixel) {
+		pixel_bytes = drm_format_plane_cpp(pixel_format, 0);
+		switch (pixel_bytes) {
 		default:
-		case 8:
+		case 1:
 			tile_height = 64;
 			break;
-		case 16:
-		case 32:
+		case 2:
+		case 4:
 			tile_height = 32;
 			break;
-		case 64:
+		case 8:
 			tile_height = 16;
 			break;
-		case 128:
+		case 16:
 			WARN_ONCE(1,
 				  "128-bit pixels are not supported for display!");
 			tile_height = 16;
@@ -2278,7 +2277,15 @@ intel_fb_align_height(struct drm_device *dev, int height,
 		break;
 	}
 
-	return ALIGN(height, tile_height);
+	return tile_height;
+}
+
+unsigned int
+intel_fb_align_height(struct drm_device *dev, unsigned int height,
+		      uint32_t pixel_format, uint64_t fb_format_modifier)
+{
+	return ALIGN(height, intel_tile_height(dev, pixel_format,
+					       fb_format_modifier));
 }
 
 int
@@ -6811,7 +6818,7 @@ i9xx_get_initial_plane_config(struct intel_crtc *crtc,
 	u32 val, base, offset;
 	int pipe = crtc->pipe, plane = crtc->plane;
 	int fourcc, pixel_format;
-	int aligned_height;
+	unsigned int aligned_height;
 	struct drm_framebuffer *fb;
 	struct intel_framebuffer *intel_fb;
 
@@ -7849,7 +7856,7 @@ skylake_get_initial_plane_config(struct intel_crtc *crtc,
 	u32 val, base, offset, stride_mult, tiling;
 	int pipe = crtc->pipe;
 	int fourcc, pixel_format;
-	int aligned_height;
+	unsigned int aligned_height;
 	struct drm_framebuffer *fb;
 	struct intel_framebuffer *intel_fb;
 
@@ -7957,7 +7964,7 @@ ironlake_get_initial_plane_config(struct intel_crtc *crtc,
 	u32 val, base, offset;
 	int pipe = crtc->pipe;
 	int fourcc, pixel_format;
-	int aligned_height;
+	unsigned int aligned_height;
 	struct drm_framebuffer *fb;
 	struct intel_framebuffer *intel_fb;
 
@@ -12883,7 +12890,7 @@ static int intel_framebuffer_init(struct drm_device *dev,
 				  struct drm_mode_fb_cmd2 *mode_cmd,
 				  struct drm_i915_gem_object *obj)
 {
-	int aligned_height;
+	unsigned int aligned_height;
 	int ret;
 	u32 pitch_limit, stride_alignment;
 

drivers/gpu/drm/i915/intel_drv.h

@@ -901,9 +901,10 @@ void intel_frontbuffer_flip(struct drm_device *dev,
 	intel_frontbuffer_flush(dev, frontbuffer_bits);
 }
 
-int intel_fb_align_height(struct drm_device *dev, int height,
-			  uint32_t pixel_format,
-			  uint64_t fb_format_modifier);
+unsigned int intel_fb_align_height(struct drm_device *dev,
+				   unsigned int height,
+				   uint32_t pixel_format,
+				   uint64_t fb_format_modifier);
 void intel_fb_obj_flush(struct drm_i915_gem_object *obj, bool retire);
 
 u32 intel_fb_stride_alignment(struct drm_device *dev, uint64_t fb_modifier,