drm/drm_fb_helper: fix fbdev with sparc64

From Sam Ravnborg
cea0a7943a30a6d0320c8558a844dd27e8f0aa8b in linux 5.7.y/5.7.15
2a1658bf922ffd9b7907e270a7d9cdc9643fc45d in mainline linux

2 files changed, 17 insertions, 1 deletions

diff --git a/sys/dev/pci/drm/drm_fb_helper.c b/sys/dev/pci/drm/drm_fb_helper.c
index 13929cc0b08..60fe7c8d8b0 100644
--- a/sys/dev/pci/drm/drm_fb_helper.c
+++ b/sys/dev/pci/drm/drm_fb_helper.c
@@ -405,7 +405,11 @@ 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/sys/dev/pci/drm/include/drm/drm_mode_config.h b/sys/dev/pci/drm/include/drm/drm_mode_config.h
index d22c3f0ac67..e4185da28dc 100644
--- a/sys/dev/pci/drm/include/drm/drm_mode_config.h
+++ b/sys/dev/pci/drm/include/drm/drm_mode_config.h
@@ -866,6 +866,18 @@ 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:
 	 *
 	 * Special hack for legacy ADDFB to keep nouveau userspace happy. Should