drm/format-helper: Rework XRGB8888-to-RGB888 conversion

Update XRGB8888-to-RGB888 conversion to support struct iosys_map
and convert all users. Although these are single-plane color formats,
the new interface supports multi-plane formats for consistency with
drm_fb_blit().

v2:
	* update documentation (Sam)
	* add TODO on vaddr location (Sam)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220808125406.20752-8-tzimmermann@suse.de

3 files changed, 33 insertions, 31 deletions

diff --git a/drivers/gpu/drm/drm_format_helper.c b/drivers/gpu/drm/drm_format_helper.c
index a77291d2f9b9..3ee57dc8bcc5 100644
--- a/drivers/gpu/drm/drm_format_helper.c
+++ b/drivers/gpu/drm/drm_format_helper.c
@@ -420,41 +420,45 @@ static void drm_fb_xrgb8888_to_rgb888_line(void *dbuf, const void *sbuf, unsigne
 
 /**
  * drm_fb_xrgb8888_to_rgb888 - Convert XRGB8888 to RGB888 clip buffer
- * @dst: RGB888 destination buffer
- * @dst_pitch: Number of bytes between two consecutive scanlines within dst
- * @src: XRGB8888 source buffer
+ * @dst: Array of RGB888 destination buffers
+ * @dst_pitch: Array of numbers of bytes between the start of two consecutive scanlines
+ *             within @dst; can be NULL if scanlines are stored next to each other.
+ * @vmap: Array of XRGB8888 source buffers
  * @fb: DRM framebuffer
  * @clip: Clip rectangle area to copy
  *
- * Drivers can use this function for RGB888 devices that don't natively
- * support XRGB8888.
- */
-void drm_fb_xrgb8888_to_rgb888(void *dst, unsigned int dst_pitch, const void *src,
-			       const struct drm_framebuffer *fb, const struct drm_rect *clip)
-{
-	drm_fb_xfrm(dst, dst_pitch, 3, src, fb, clip, false, drm_fb_xrgb8888_to_rgb888_line);
-}
-EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb888);
-
-/**
- * drm_fb_xrgb8888_to_rgb888_toio - Convert XRGB8888 to RGB888 clip buffer
- * @dst: RGB565 destination buffer (iomem)
- * @dst_pitch: Number of bytes between two consecutive scanlines within dst
- * @vaddr: XRGB8888 source buffer
- * @fb: DRM framebuffer
- * @clip: Clip rectangle area to copy
+ * This function copies parts of a framebuffer to display memory and converts the
+ * color format during the process. Destination and framebuffer formats must match. The
+ * parameters @dst, @dst_pitch and @vmap refer to arrays. Each array must have at
+ * least as many entries as there are planes in @fb's format. Each entry stores the
+ * value for the format's respective color plane at the same index.
+ *
+ * This function does not apply clipping on @dst (i.e. the destination is at the
+ * top-left corner).
  *
  * Drivers can use this function for RGB888 devices that don't natively
  * support XRGB8888.
  */
-void drm_fb_xrgb8888_to_rgb888_toio(void __iomem *dst, unsigned int dst_pitch,
-				    const void *vaddr, const struct drm_framebuffer *fb,
-				    const struct drm_rect *clip)
+void drm_fb_xrgb8888_to_rgb888(struct iosys_map *dst, const unsigned int *dst_pitch,
+			       const struct iosys_map *vmap, const struct drm_framebuffer *fb,
+			       const struct drm_rect *clip)
 {
-	drm_fb_xfrm_toio(dst, dst_pitch, 3, vaddr, fb, clip, false,
-			 drm_fb_xrgb8888_to_rgb888_line);
+	static const unsigned int default_dst_pitch[DRM_FORMAT_MAX_PLANES] = {
+		0, 0, 0, 0
+	};
+
+	if (!dst_pitch)
+		dst_pitch = default_dst_pitch;
+
+	/* TODO: handle vmap in I/O memory here */
+	if (dst[0].is_iomem)
+		drm_fb_xfrm_toio(dst[0].vaddr_iomem, dst_pitch[0], 3, vmap[0].vaddr, fb,
+				 clip, false, drm_fb_xrgb8888_to_rgb888_line);
+	else
+		drm_fb_xfrm(dst[0].vaddr, dst_pitch[0], 3, vmap[0].vaddr, fb,
+			    clip, false, drm_fb_xrgb8888_to_rgb888_line);
 }
-EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb888_toio);
+EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb888);
 
 static void drm_fb_rgb565_to_xrgb8888_line(void *dbuf, const void *sbuf, unsigned int pixels)
 {
@@ -638,8 +642,7 @@ int drm_fb_blit(struct iosys_map *dst, const unsigned int *dst_pitch, uint32_t d
 		}
 	} else if (dst_format == DRM_FORMAT_RGB888) {
 		if (fb_format == DRM_FORMAT_XRGB8888) {
-			drm_fb_xrgb8888_to_rgb888_toio(dst[0].vaddr_iomem, dst_pitch[0],
-						       vmap[0].vaddr, fb, clip);
+			drm_fb_xrgb8888_to_rgb888(dst, dst_pitch, vmap, fb, clip);
 			return 0;
 		}
 	} else if (dst_format == DRM_FORMAT_XRGB8888) {
diff --git a/drivers/gpu/drm/gud/gud_pipe.c b/drivers/gpu/drm/gud/gud_pipe.c
index a43eb6645352..0caa228f736d 100644
--- a/drivers/gpu/drm/gud/gud_pipe.c
+++ b/drivers/gpu/drm/gud/gud_pipe.c
@@ -201,7 +201,7 @@ retry:
 			drm_fb_xrgb8888_to_rgb565(&dst, NULL, map_data, fb, rect,
 						  gud_is_big_endian());
 		} else if (format->format == DRM_FORMAT_RGB888) {
-			drm_fb_xrgb8888_to_rgb888(buf, 0, vaddr, fb, rect);
+			drm_fb_xrgb8888_to_rgb888(&dst, NULL, map_data, fb, rect);
 		} else {
 			len = gud_xrgb8888_to_color(buf, format, vaddr, fb, rect);
 		}
diff --git a/drivers/gpu/drm/tiny/cirrus.c b/drivers/gpu/drm/tiny/cirrus.c
index 9cd398e4700b..354d5e854a6f 100644
--- a/drivers/gpu/drm/tiny/cirrus.c
+++ b/drivers/gpu/drm/tiny/cirrus.c
@@ -321,7 +321,6 @@ static int cirrus_fb_blit_rect(struct drm_framebuffer *fb,
 {
 	struct cirrus_device *cirrus = to_cirrus(fb->dev);
 	struct iosys_map dst;
-	void *vaddr = vmap->vaddr; /* TODO: Use mapping abstraction properly */
 	int idx;
 
 	if (!drm_dev_enter(&cirrus->dev, &idx))
@@ -339,7 +338,7 @@ static int cirrus_fb_blit_rect(struct drm_framebuffer *fb,
 
 	} else if (fb->format->cpp[0] == 4 && cirrus->cpp == 3) {
 		iosys_map_incr(&dst, drm_fb_clip_offset(cirrus->pitch, fb->format, rect));
-		drm_fb_xrgb8888_to_rgb888_toio(dst.vaddr_iomem, cirrus->pitch, vaddr, fb, rect);
+		drm_fb_xrgb8888_to_rgb888(&dst, &cirrus->pitch, vmap, fb, rect);
 
 	} else {
 		WARN_ON_ONCE("cpp mismatch");