diff --git a/drivers/gpu/drm/bochs/bochs_kms.c b/drivers/gpu/drm/bochs/bochs_kms.c
index 02a9c1ed165b..fa50ab2523d4 100644
--- a/drivers/gpu/drm/bochs/bochs_kms.c
+++ b/drivers/gpu/drm/bochs/bochs_kms.c
@@ -194,6 +194,7 @@ int bochs_kms_init(struct bochs_device *bochs)
 	bochs->dev->mode_config.preferred_depth = 24;
 	bochs->dev->mode_config.prefer_shadow = 0;
 	bochs->dev->mode_config.prefer_shadow_fbdev = 1;
+	bochs->dev->mode_config.fbdev_use_iomem = true;
 	bochs->dev->mode_config.quirk_addfb_prefer_host_byte_order = true;
 
 	bochs->dev->mode_config.funcs = &bochs_mode_funcs;
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 8d193a58363d..6b8502bcf0fd 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -390,7 +390,11 @@ static void drm_fb_helper_dirty_blit_real(struct drm_fb_helper *fb_helper,
 	unsigned int y;
 
 	for (y = clip->y1; y < clip->y2; y++) {
-		memcpy(dst, src, len);
+		if (!fb_helper->dev->mode_config.fbdev_use_iomem)
+			memcpy(dst, src, len);
+		else
+			memcpy_toio((void __iomem *)dst, src, len);
+
 		src += fb->pitches[0];
 		dst += fb->pitches[0];
 	}
diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h
index 3bcbe30339f0..198b9d060008 100644
--- a/include/drm/drm_mode_config.h
+++ b/include/drm/drm_mode_config.h
@@ -865,6 +865,18 @@ struct drm_mode_config {
 	 */
 	bool prefer_shadow_fbdev;
 
+	/**
+	 * @fbdev_use_iomem:
+	 *
+	 * Set to true if framebuffer reside in iomem.
+	 * When set to true memcpy_toio() is used when copying the framebuffer in
+	 * drm_fb_helper.drm_fb_helper_dirty_blit_real().
+	 *
+	 * FIXME: This should be replaced with a per-mapping is_iomem
+	 * flag (like ttm does), and then used everywhere in fbdev code.
+	 */
+	bool fbdev_use_iomem;
+
 	/**
 	 * @quirk_addfb_prefer_xbgr_30bpp:
 	 *