drm/armada: use common helper for plane base address

Use a common helper to calculate the plane base address(es) for the
framebuffer.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

drivers/gpu/drm/armada/armada_crtc.c

@@ -165,19 +165,37 @@ static void armada_drm_crtc_update(struct armada_crtc *dcrtc)
 	}
 }
 
+void armada_drm_plane_calc_addrs(u32 *addrs, struct drm_framebuffer *fb,
+	int x, int y)
+{
+	u32 addr = drm_fb_obj(fb)->dev_addr;
+	u32 pixel_format = fb->pixel_format;
+	int num_planes = drm_format_num_planes(pixel_format);
+	int i;
+
+	if (num_planes > 3)
+		num_planes = 3;
+
+	for (i = 0; i < num_planes; i++)
+		addrs[i] = addr + fb->offsets[i] + y * fb->pitches[i] +
+			     x * drm_format_plane_cpp(pixel_format, i);
+	for (; i < 3; i++)
+		addrs[i] = 0;
+}
+
 static unsigned armada_drm_crtc_calc_fb(struct drm_framebuffer *fb,
 	int x, int y, struct armada_regs *regs, bool interlaced)
 {
-	struct armada_gem_object *obj = drm_fb_obj(fb);
 	unsigned pitch = fb->pitches[0];
-	unsigned offset = y * pitch + x * fb->bits_per_pixel / 8;
-	uint32_t addr_odd, addr_even;
+	u32 addrs[3], addr_odd, addr_even;
 	unsigned i = 0;
 
 	DRM_DEBUG_DRIVER("pitch %u x %d y %d bpp %d\n",
 		pitch, x, y, fb->bits_per_pixel);
 
-	addr_odd = addr_even = obj->dev_addr + offset;
+	armada_drm_plane_calc_addrs(addrs, fb, x, y);
+
+	addr_odd = addr_even = addrs[0];
 
 	if (interlaced) {
 		addr_even += pitch;

drivers/gpu/drm/armada/armada_crtc.h

@@ -62,6 +62,8 @@ int armada_drm_plane_work_queue(struct armada_crtc *dcrtc,
 int armada_drm_plane_work_wait(struct armada_plane *plane, long timeout);
 struct armada_plane_work *armada_drm_plane_work_cancel(
 	struct armada_crtc *dcrtc, struct armada_plane *plane);
+void armada_drm_plane_calc_addrs(u32 *addrs, struct drm_framebuffer *fb,
+	int x, int y);
 
 struct armada_crtc {
 	struct drm_crtc		crtc;

drivers/gpu/drm/armada/armada_overlay.c

@@ -169,9 +169,8 @@ armada_ovl_plane_update(struct drm_plane *plane, struct drm_crtc *crtc,
 		armada_drm_plane_work_cancel(dcrtc, &dplane->base);
 
 	if (plane->fb != fb) {
-		struct armada_gem_object *obj = drm_fb_obj(fb);
-		uint32_t addr[3], pixel_format;
-		int i, num_planes, hsub;
+		u32 addrs[3], pixel_format;
+		int num_planes, hsub;
 
 		/*
 		 * Take a reference on the new framebuffer - we want to
@@ -185,6 +184,8 @@ armada_ovl_plane_update(struct drm_plane *plane, struct drm_crtc *crtc,
 		src_y = src.y1 >> 16;
 		src_x = src.x1 >> 16;
 
+		armada_drm_plane_calc_addrs(addrs, fb, src_x, src_y);
+
 		pixel_format = fb->pixel_format;
 		hsub = drm_format_horz_chroma_subsampling(pixel_format);
 		num_planes = drm_format_num_planes(pixel_format);
@@ -197,24 +198,17 @@ armada_ovl_plane_update(struct drm_plane *plane, struct drm_crtc *crtc,
 		if (src_x & (hsub - 1) && num_planes == 1)
 			ctrl0 ^= CFG_DMA_MOD(CFG_SWAPUV);
 
-		for (i = 0; i < num_planes; i++)
-			addr[i] = obj->dev_addr + fb->offsets[i] +
-				  src_y * fb->pitches[i] +
-				  src_x * drm_format_plane_cpp(pixel_format, i);
-		for (; i < ARRAY_SIZE(addr); i++)
-			addr[i] = 0;
-
-		armada_reg_queue_set(dplane->vbl.regs, idx, addr[0],
+		armada_reg_queue_set(dplane->vbl.regs, idx, addrs[0],
 				     LCD_SPU_DMA_START_ADDR_Y0);
-		armada_reg_queue_set(dplane->vbl.regs, idx, addr[1],
+		armada_reg_queue_set(dplane->vbl.regs, idx, addrs[1],
 				     LCD_SPU_DMA_START_ADDR_U0);
-		armada_reg_queue_set(dplane->vbl.regs, idx, addr[2],
+		armada_reg_queue_set(dplane->vbl.regs, idx, addrs[2],
 				     LCD_SPU_DMA_START_ADDR_V0);
-		armada_reg_queue_set(dplane->vbl.regs, idx, addr[0],
+		armada_reg_queue_set(dplane->vbl.regs, idx, addrs[0],
 				     LCD_SPU_DMA_START_ADDR_Y1);
-		armada_reg_queue_set(dplane->vbl.regs, idx, addr[1],
+		armada_reg_queue_set(dplane->vbl.regs, idx, addrs[1],
 				     LCD_SPU_DMA_START_ADDR_U1);
-		armada_reg_queue_set(dplane->vbl.regs, idx, addr[2],
+		armada_reg_queue_set(dplane->vbl.regs, idx, addrs[2],
 				     LCD_SPU_DMA_START_ADDR_V1);
 
 		val = fb->pitches[0] << 16 | fb->pitches[0];