[PATCH 1/4] drm: add generic convert_lines() function for format conversions.

[PATCH 1/4] drm: add generic convert_lines() function for format conversions.

[Gerd Hoffmann]

Introduce some infrastructure to handle format conversions:

 * New struct drm_format_convert containing the cpp for src
   and dst with a function pointer to actually convert a
   single scanline.
 * generic convert_lines() function which uses a struct
   drm_format_convert pointer to convert a rectangle.

drm_fb_swab16() has been switched over to the new
convert_lines() function as showcase.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 drivers/gpu/drm/drm_format_helper.c | 84 +++++++++++++++++++++--------
 1 file changed, 63 insertions(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/drm_format_helper.c b/drivers/gpu/drm/drm_format_helper.c
index 00d716f14173..f32e0173600c 100644
--- a/drivers/gpu/drm/drm_format_helper.c
+++ b/drivers/gpu/drm/drm_format_helper.c
@@ -16,6 +16,61 @@
 #include <drm/drm_fourcc.h>
 #include <drm/drm_rect.h>
 
+struct drm_format_convert {
+	u32 dst_cpp;
+	u32 src_cpp;
+	void (*func)(void *dst, void *src, u32 pixels);
+};
+
+static void convert_swab16_fn(void *dst, void *src, u32 pixels)
+{
+	u16 *sbuf = src;
+	u16 *dbuf = dst;
+	u32 x;
+
+	for (x = 0; x < pixels; x++)
+		dbuf[x] = swab16(sbuf[16]);
+}
+
+static struct drm_format_convert convert_swab16 = {
+	.dst_cpp = 2,
+	.src_cpp = 2,
+	.func = convert_swab16_fn,
+};
+
+static void convert_lines(void *dst, unsigned int dst_pitch,
+			  void *src, unsigned int src_pitch,
+			  unsigned int pixels,
+			  unsigned int lines,
+			  struct drm_format_convert *conv)
+{
+	u32 src_linelength = pixels * conv->src_cpp;
+	u32 y;
+	void *sbuf;
+
+	/*
+	 * The cma memory is write-combined so reads are uncached.
+	 * Speed up by fetching one line at a time.
+	 */
+	sbuf = kmalloc(src_linelength, GFP_KERNEL);
+	if (!sbuf)
+		return;
+
+	for (y = 0; y < lines; y++) {
+		memcpy(sbuf, src, src_linelength);
+		conv->func(dst, sbuf, pixels);
+		src += src_pitch;
+		dst += dst_pitch;
+	}
+
+	kfree(sbuf);
+}
+
+static u32 clip_offset(struct drm_rect *clip, u32 pitch, u32 cpp)
+{
+	return (clip->y1 * pitch) + (clip->x1 * cpp);
+}
+
 static void drm_fb_memcpy_lines(void *dst, unsigned int dst_pitch,
 				void *src, unsigned int src_pitch,
 				unsigned int linelength, unsigned int lines)
@@ -85,28 +140,15 @@ EXPORT_SYMBOL(drm_fb_memcpy_dstclip);
 void drm_fb_swab16(u16 *dst, void *vaddr, struct drm_framebuffer *fb,
 		   struct drm_rect *clip)
 {
-	size_t len = (clip->x2 - clip->x1) * sizeof(u16);
-	unsigned int x, y;
-	u16 *src, *buf;
+	struct drm_format_convert *conv = &convert_swab16;
+	unsigned int src_offset =
+		clip_offset(clip, fb->pitches[0], conv->src_cpp);
+	size_t pixels = (clip->x2 - clip->x1);
+	size_t lines = (clip->y2 - clip->y1);
 
-	/*
-	 * The cma memory is write-combined so reads are uncached.
-	 * Speed up by fetching one line at a time.
-	 */
-	buf = kmalloc(len, GFP_KERNEL);
-	if (!buf)
-		return;
-
-	for (y = clip->y1; y < clip->y2; y++) {
-		src = vaddr + (y * fb->pitches[0]);
-		src += clip->x1;
-		memcpy(buf, src, len);
-		src = buf;
-		for (x = clip->x1; x < clip->x2; x++)
-			*dst++ = swab16(*src++);
-	}
-
-	kfree(buf);
+	convert_lines(dst, pixels * conv->dst_cpp,
+		      vaddr + src_offset, fb->pitches[0],
+		      pixels, lines, conv);
 }
 EXPORT_SYMBOL(drm_fb_swab16);
 
-- 
2.18.1

[PATCH 2/4] drm: use convert_lines() in xrgb8888_to_rgb565 helpers.

[Gerd Hoffmann]

Also add two conversion functions for the swab / not swab cases.
That way we have to check the swab flag only once.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 drivers/gpu/drm/drm_format_helper.c | 117 +++++++++++++++-------------
 1 file changed, 62 insertions(+), 55 deletions(-)

diff --git a/drivers/gpu/drm/drm_format_helper.c b/drivers/gpu/drm/drm_format_helper.c
index f32e0173600c..b8d17cd0a9f8 100644
--- a/drivers/gpu/drm/drm_format_helper.c
+++ b/drivers/gpu/drm/drm_format_helper.c
@@ -38,6 +38,46 @@ static struct drm_format_convert convert_swab16 = {
 	.func = convert_swab16_fn,
 };
 
+static void convert_xrgb8888_to_rgb565_fn(void *dst, void *src, u32 pixels)
+{
+	u32 *sbuf = src;
+	u16 *dbuf = dst;
+	u32 x;
+
+	for (x = 0; x < pixels; x++) {
+		dbuf[x] = ((sbuf[x] & 0x00F80000) >> 8) |
+			((sbuf[x] & 0x0000FC00) >> 5) |
+			((sbuf[x] & 0x000000F8) >> 3);
+	}
+}
+
+static struct drm_format_convert convert_xrgb8888_to_rgb565 = {
+	.dst_cpp = 2,
+	.src_cpp = 4,
+	.func = convert_xrgb8888_to_rgb565_fn,
+};
+
+static void convert_xrgb8888_to_rgb565_swab_fn(void *dst, void *src, u32 pixels)
+{
+	u32 *sbuf = src;
+	u16 *dbuf = dst;
+	u16 val16;
+	u32 x;
+
+	for (x = 0; x < pixels; x++) {
+		val16 = ((sbuf[x] & 0x00F80000) >> 8) |
+			((sbuf[x] & 0x0000FC00) >> 5) |
+			((sbuf[x] & 0x000000F8) >> 3);
+		dbuf[x] = swab16(val16);
+	}
+}
+
+static struct drm_format_convert convert_xrgb8888_to_rgb565_swap = {
+	.dst_cpp = 2,
+	.src_cpp = 4,
+	.func = convert_xrgb8888_to_rgb565_swab_fn,
+};
+
 static void convert_lines(void *dst, unsigned int dst_pitch,
 			  void *src, unsigned int src_pitch,
 			  unsigned int pixels,
@@ -152,44 +192,6 @@ void drm_fb_swab16(u16 *dst, void *vaddr, struct drm_framebuffer *fb,
 }
 EXPORT_SYMBOL(drm_fb_swab16);
 
-static void drm_fb_xrgb8888_to_rgb565_lines(void *dst, unsigned int dst_pitch,
-					    void *src, unsigned int src_pitch,
-					    unsigned int src_linelength,
-					    unsigned int lines,
-					    bool swap)
-{
-	unsigned int linepixels = src_linelength / sizeof(u32);
-	unsigned int x, y;
-	u32 *sbuf;
-	u16 *dbuf, val16;
-
-	/*
-	 * The cma memory is write-combined so reads are uncached.
-	 * Speed up by fetching one line at a time.
-	 */
-	sbuf = kmalloc(src_linelength, GFP_KERNEL);
-	if (!sbuf)
-		return;
-
-	for (y = 0; y < lines; y++) {
-		memcpy(sbuf, src, src_linelength);
-		dbuf = dst;
-		for (x = 0; x < linepixels; x++) {
-			val16 = ((sbuf[x] & 0x00F80000) >> 8) |
-				((sbuf[x] & 0x0000FC00) >> 5) |
-				((sbuf[x] & 0x000000F8) >> 3);
-			if (swap)
-				*dbuf++ = swab16(val16);
-			else
-				*dbuf++ = val16;
-		}
-		src += src_pitch;
-		dst += dst_pitch;
-	}
-
-	kfree(sbuf);
-}
-
 /**
  * drm_fb_xrgb8888_to_rgb565 - Convert XRGB8888 to RGB565 clip buffer
  * @dst: RGB565 destination buffer
@@ -208,15 +210,17 @@ void drm_fb_xrgb8888_to_rgb565(void *dst, void *vaddr,
 			       struct drm_framebuffer *fb,
 			       struct drm_rect *clip, bool swap)
 {
-	unsigned int src_offset = (clip->y1 * fb->pitches[0])
-		+ (clip->x1 * sizeof(u32));
-	size_t src_len = (clip->x2 - clip->x1) * sizeof(u32);
-	size_t dst_len = (clip->x2 - clip->x1) * sizeof(u16);
+	struct drm_format_convert *conv = swap
+		? &convert_xrgb8888_to_rgb565_swap
+		: &convert_xrgb8888_to_rgb565;
+	unsigned int src_offset =
+		clip_offset(clip, fb->pitches[0], conv->src_cpp);
+	size_t pixels = (clip->x2 - clip->x1);
+	size_t lines = (clip->y2 - clip->y1);
 
-	drm_fb_xrgb8888_to_rgb565_lines(dst, dst_len,
-					vaddr + src_offset, fb->pitches[0],
-					src_len, clip->y2 - clip->y1,
-					swap);
+	convert_lines(dst, pixels * conv->dst_cpp,
+		      vaddr + src_offset, fb->pitches[0],
+		      pixels, lines, conv);
 }
 EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565);
 
@@ -239,16 +243,19 @@ void drm_fb_xrgb8888_to_rgb565_dstclip(void *dst, unsigned int dst_pitch,
 				       void *vaddr, struct drm_framebuffer *fb,
 				       struct drm_rect *clip, bool swap)
 {
-	unsigned int src_offset = (clip->y1 * fb->pitches[0])
-		+ (clip->x1 * sizeof(u32));
-	unsigned int dst_offset = (clip->y1 * dst_pitch)
-		+ (clip->x1 * sizeof(u16));
-	size_t src_len = (clip->x2 - clip->x1) * sizeof(u32);
+	struct drm_format_convert *conv = swap
+		? &convert_xrgb8888_to_rgb565_swap
+		: &convert_xrgb8888_to_rgb565;
+	unsigned int src_offset =
+		clip_offset(clip, fb->pitches[0], conv->src_cpp);
+	unsigned int dst_offset =
+		clip_offset(clip, dst_pitch, conv->dst_cpp);
+	size_t pixels = (clip->x2 - clip->x1);
+	size_t lines = (clip->y2 - clip->y1);
 
-	drm_fb_xrgb8888_to_rgb565_lines(dst + dst_offset, dst_pitch,
-					vaddr + src_offset, fb->pitches[0],
-					src_len, clip->y2 - clip->y1,
-					swap);
+	convert_lines(dst + dst_offset, dst_pitch,
+		      vaddr + src_offset, fb->pitches[0],
+		      pixels, lines, conv);
 }
 EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565_dstclip);
 
-- 
2.18.1

[PATCH 3/4] drm: use convert_lines() in xrgb8888_to_rgb565 helpers.

[Gerd Hoffmann]

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 drivers/gpu/drm/drm_format_helper.c | 66 +++++++++++++----------------
 1 file changed, 29 insertions(+), 37 deletions(-)

diff --git a/drivers/gpu/drm/drm_format_helper.c b/drivers/gpu/drm/drm_format_helper.c
index b8d17cd0a9f8..01d9ea134618 100644
--- a/drivers/gpu/drm/drm_format_helper.c
+++ b/drivers/gpu/drm/drm_format_helper.c
@@ -78,6 +78,25 @@ static struct drm_format_convert convert_xrgb8888_to_rgb565_swap = {
 	.func = convert_xrgb8888_to_rgb565_swab_fn,
 };
 
+static void convert_xrgb8888_to_rgb888_fn(void *dst, void *src, u32 pixels)
+{
+	u32 *sbuf = src;
+	u8 *dbuf = dst;
+	u32 x;
+
+	for (x = 0; x < pixels; x++) {
+		*dbuf++ = (sbuf[x] & 0x000000FF) >>  0;
+		*dbuf++ = (sbuf[x] & 0x0000FF00) >>  8;
+		*dbuf++ = (sbuf[x] & 0x00FF0000) >> 16;
+	}
+}
+
+static struct drm_format_convert convert_xrgb8888_to_rgb888 = {
+	.dst_cpp = 3,
+	.src_cpp = 4,
+	.func = convert_xrgb8888_to_rgb888_fn,
+};
+
 static void convert_lines(void *dst, unsigned int dst_pitch,
 			  void *src, unsigned int src_pitch,
 			  unsigned int pixels,
@@ -259,35 +278,6 @@ void drm_fb_xrgb8888_to_rgb565_dstclip(void *dst, unsigned int dst_pitch,
 }
 EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565_dstclip);
 
-static void drm_fb_xrgb8888_to_rgb888_lines(void *dst, unsigned int dst_pitch,
-					    void *src, unsigned int src_pitch,
-					    unsigned int src_linelength,
-					    unsigned int lines)
-{
-	unsigned int linepixels = src_linelength / 3;
-	unsigned int x, y;
-	u32 *sbuf;
-	u8 *dbuf;
-
-	sbuf = kmalloc(src_linelength, GFP_KERNEL);
-	if (!sbuf)
-		return;
-
-	for (y = 0; y < lines; y++) {
-		memcpy(sbuf, src, src_linelength);
-		dbuf = dst;
-		for (x = 0; x < linepixels; x++) {
-			*dbuf++ = (sbuf[x] & 0x000000FF) >>  0;
-			*dbuf++ = (sbuf[x] & 0x0000FF00) >>  8;
-			*dbuf++ = (sbuf[x] & 0x00FF0000) >> 16;
-		}
-		src += src_pitch;
-		dst += dst_pitch;
-	}
-
-	kfree(sbuf);
-}
-
 /**
  * drm_fb_xrgb8888_to_rgb888_dstclip - Convert XRGB8888 to RGB888 clip buffer
  * @dst: RGB565 destination buffer
@@ -307,15 +297,17 @@ void drm_fb_xrgb8888_to_rgb888_dstclip(void *dst, unsigned int dst_pitch,
 				       void *vaddr, struct drm_framebuffer *fb,
 				       struct drm_rect *clip)
 {
-	unsigned int src_offset = (clip->y1 * fb->pitches[0])
-		+ (clip->x1 * sizeof(u32));
-	unsigned int dst_offset = (clip->y1 * dst_pitch)
-		+ (clip->x1 * 3);
-	size_t src_len = (clip->x2 - clip->x1) * sizeof(u32);
+	struct drm_format_convert *conv = &convert_xrgb8888_to_rgb888;
+	unsigned int src_offset =
+		clip_offset(clip, fb->pitches[0], conv->src_cpp);
+	unsigned int dst_offset =
+		clip_offset(clip, dst_pitch, conv->dst_cpp);
+	size_t pixels = (clip->x2 - clip->x1);
+	size_t lines = (clip->y2 - clip->y1);
 
-	drm_fb_xrgb8888_to_rgb888_lines(dst + dst_offset, dst_pitch,
-					vaddr + src_offset, fb->pitches[0],
-					src_len, clip->y2 - clip->y1);
+	convert_lines(dst + dst_offset, dst_pitch,
+		      vaddr + src_offset, fb->pitches[0],
+		      pixels, lines, conv);
 }
 EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb888_dstclip);
 
-- 
2.18.1

[PATCH 4/4] drm: add convert_lines_toio() variant, fix cirrus builds on powerpc.

[Gerd Hoffmann]

The __io_virt() macro is not available on all architectures, so cirrus
can't simply pass a pointer to io memory down to the format conversion
helpers.  The format conversion helpers must use memcpy_toio() instead.

Add a convert_lines_toio() variant which does just that.  Switch the
drm_fb_*_dstclip() functions used by cirrus to accept a __iomem pointer
as destination and pass that down to convert_lines_toio().  Fix the
calls in the cirrus driver to not use __io_virt() any more.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 include/drm/drm_format_helper.h     |  9 ++--
 drivers/gpu/drm/cirrus/cirrus.c     |  6 +--
 drivers/gpu/drm/drm_format_helper.c | 74 ++++++++++++++++++++++-------
 3 files changed, 67 insertions(+), 22 deletions(-)

diff --git a/include/drm/drm_format_helper.h b/include/drm/drm_format_helper.h
index 6f84380757ee..3532b76c2340 100644
--- a/include/drm/drm_format_helper.h
+++ b/include/drm/drm_format_helper.h
@@ -15,17 +15,20 @@ struct drm_rect;
 
 void drm_fb_memcpy(void *dst, void *vaddr, struct drm_framebuffer *fb,
 		   struct drm_rect *clip);
-void drm_fb_memcpy_dstclip(void *dst, void *vaddr, struct drm_framebuffer *fb,
+void drm_fb_memcpy_dstclip(void __iomem *dst, void *vaddr,
+			   struct drm_framebuffer *fb,
 			   struct drm_rect *clip);
 void drm_fb_swab16(u16 *dst, void *vaddr, struct drm_framebuffer *fb,
 		   struct drm_rect *clip);
 void drm_fb_xrgb8888_to_rgb565(void *dst, void *vaddr,
 			       struct drm_framebuffer *fb,
 			       struct drm_rect *clip, bool swap);
-void drm_fb_xrgb8888_to_rgb565_dstclip(void *dst, unsigned int dst_pitch,
+void drm_fb_xrgb8888_to_rgb565_dstclip(void __iomem *dst,
+				       unsigned int dst_pitch,
 				       void *vaddr, struct drm_framebuffer *fb,
 				       struct drm_rect *clip, bool swap);
-void drm_fb_xrgb8888_to_rgb888_dstclip(void *dst, unsigned int dst_pitch,
+void drm_fb_xrgb8888_to_rgb888_dstclip(void __iomem *dst,
+				       unsigned int dst_pitch,
 				       void *vaddr, struct drm_framebuffer *fb,
 				       struct drm_rect *clip);
 void drm_fb_xrgb8888_to_gray8(u8 *dst, void *vaddr, struct drm_framebuffer *fb,
diff --git a/drivers/gpu/drm/cirrus/cirrus.c b/drivers/gpu/drm/cirrus/cirrus.c
index 5095b8ce52c2..be4ea370ba31 100644
--- a/drivers/gpu/drm/cirrus/cirrus.c
+++ b/drivers/gpu/drm/cirrus/cirrus.c
@@ -307,16 +307,16 @@ static int cirrus_fb_blit_rect(struct drm_framebuffer *fb,
 		return -ENOMEM;
 
 	if (cirrus->cpp == fb->format->cpp[0])
-		drm_fb_memcpy_dstclip(__io_virt(cirrus->vram),
+		drm_fb_memcpy_dstclip(cirrus->vram,
 				      vmap, fb, rect);
 
 	else if (fb->format->cpp[0] == 4 && cirrus->cpp == 2)
-		drm_fb_xrgb8888_to_rgb565_dstclip(__io_virt(cirrus->vram),
+		drm_fb_xrgb8888_to_rgb565_dstclip(cirrus->vram,
 						  cirrus->pitch,
 						  vmap, fb, rect, false);
 
 	else if (fb->format->cpp[0] == 4 && cirrus->cpp == 3)
-		drm_fb_xrgb8888_to_rgb888_dstclip(__io_virt(cirrus->vram),
+		drm_fb_xrgb8888_to_rgb888_dstclip(cirrus->vram,
 						  cirrus->pitch,
 						  vmap, fb, rect);
 
diff --git a/drivers/gpu/drm/drm_format_helper.c b/drivers/gpu/drm/drm_format_helper.c
index 01d9ea134618..6a759cbaa263 100644
--- a/drivers/gpu/drm/drm_format_helper.c
+++ b/drivers/gpu/drm/drm_format_helper.c
@@ -11,6 +11,8 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 
+#include <asm/io.h>
+
 #include <drm/drm_format_helper.h>
 #include <drm/drm_framebuffer.h>
 #include <drm/drm_fourcc.h>
@@ -125,6 +127,30 @@ static void convert_lines(void *dst, unsigned int dst_pitch,
 	kfree(sbuf);
 }
 
+static void convert_lines_toio(void __iomem *dst, unsigned int dst_pitch,
+			       void *src, unsigned int src_pitch,
+			       unsigned int pixels,
+			       unsigned int lines,
+			       struct drm_format_convert *conv)
+{
+	u32 dst_linelength = pixels * conv->dst_cpp;
+	u32 y;
+	void *dbuf;
+
+	dbuf = kmalloc(dst_linelength, GFP_KERNEL);
+	if (!dbuf)
+		return;
+
+	for (y = 0; y < lines; y++) {
+		conv->func(dbuf, src, pixels);
+		memcpy_toio(dst, dbuf, dst_linelength);
+		src += src_pitch;
+		dst += dst_pitch;
+	}
+
+	kfree(dbuf);
+}
+
 static u32 clip_offset(struct drm_rect *clip, u32 pitch, u32 cpp)
 {
 	return (clip->y1 * pitch) + (clip->x1 * cpp);
@@ -143,6 +169,19 @@ static void drm_fb_memcpy_lines(void *dst, unsigned int dst_pitch,
 	}
 }
 
+static void drm_fb_memcpy_lines_toio(void __iomem *dst, unsigned int dst_pitch,
+				     void *src, unsigned int src_pitch,
+				     unsigned int linelength, unsigned int lines)
+{
+	int line;
+
+	for (line = 0; line < lines; line++) {
+		memcpy_toio(dst, src, linelength);
+		src += src_pitch;
+		dst += dst_pitch;
+	}
+}
+
 /**
  * drm_fb_memcpy - Copy clip buffer
  * @dst: Destination buffer
@@ -176,16 +215,17 @@ EXPORT_SYMBOL(drm_fb_memcpy);
  * This function applies clipping on dst, i.e. the destination is a
  * full framebuffer but only the clip rect content is copied over.
  */
-void drm_fb_memcpy_dstclip(void *dst, void *vaddr, struct drm_framebuffer *fb,
+void drm_fb_memcpy_dstclip(void __iomem *dst, void *vaddr,
+			   struct drm_framebuffer *fb,
 			   struct drm_rect *clip)
 {
 	unsigned int cpp = drm_format_plane_cpp(fb->format->format, 0);
 	unsigned int offset = (clip->y1 * fb->pitches[0]) + (clip->x1 * cpp);
 	size_t len = (clip->x2 - clip->x1) * cpp;
 
-	drm_fb_memcpy_lines(dst + offset, fb->pitches[0],
-			    vaddr + offset, fb->pitches[0],
-			    len, clip->y2 - clip->y1);
+	drm_fb_memcpy_lines_toio(dst + offset, fb->pitches[0],
+				 vaddr + offset, fb->pitches[0],
+				 len, clip->y2 - clip->y1);
 }
 EXPORT_SYMBOL(drm_fb_memcpy_dstclip);
 
@@ -245,7 +285,7 @@ EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565);
 
 /**
  * drm_fb_xrgb8888_to_rgb565_dstclip - Convert XRGB8888 to RGB565 clip buffer
- * @dst: RGB565 destination buffer
+ * @dst: RGB565 destination buffer (__iomem)
  * @dst_pitch: destination buffer pitch
  * @vaddr: XRGB8888 source buffer
  * @fb: DRM framebuffer
@@ -256,9 +296,10 @@ EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565);
  * support XRGB8888.
  *
  * This function applies clipping on dst, i.e. the destination is a
- * full framebuffer but only the clip rect content is copied over.
+ * full framebuffer, in iomem, but only the clip rect content is copied over.
  */
-void drm_fb_xrgb8888_to_rgb565_dstclip(void *dst, unsigned int dst_pitch,
+void drm_fb_xrgb8888_to_rgb565_dstclip(void __iomem *dst,
+				       unsigned int dst_pitch,
 				       void *vaddr, struct drm_framebuffer *fb,
 				       struct drm_rect *clip, bool swap)
 {
@@ -272,15 +313,15 @@ void drm_fb_xrgb8888_to_rgb565_dstclip(void *dst, unsigned int dst_pitch,
 	size_t pixels = (clip->x2 - clip->x1);
 	size_t lines = (clip->y2 - clip->y1);
 
-	convert_lines(dst + dst_offset, dst_pitch,
-		      vaddr + src_offset, fb->pitches[0],
-		      pixels, lines, conv);
+	convert_lines_toio(dst + dst_offset, dst_pitch,
+			   vaddr + src_offset, fb->pitches[0],
+			   pixels, lines, conv);
 }
 EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565_dstclip);
 
 /**
  * drm_fb_xrgb8888_to_rgb888_dstclip - Convert XRGB8888 to RGB888 clip buffer
- * @dst: RGB565 destination buffer
+ * @dst: RGB888 destination buffer (__iomem)
  * @dst_pitch: destination buffer pitch
  * @vaddr: XRGB8888 source buffer
  * @fb: DRM framebuffer
@@ -291,9 +332,10 @@ EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565_dstclip);
  * support XRGB8888.
  *
  * This function applies clipping on dst, i.e. the destination is a
- * full framebuffer but only the clip rect content is copied over.
+ * full framebuffer, in iomem, but only the clip rect content is copied over.
  */
-void drm_fb_xrgb8888_to_rgb888_dstclip(void *dst, unsigned int dst_pitch,
+void drm_fb_xrgb8888_to_rgb888_dstclip(void __iomem *dst,
+				       unsigned int dst_pitch,
 				       void *vaddr, struct drm_framebuffer *fb,
 				       struct drm_rect *clip)
 {
@@ -305,9 +347,9 @@ void drm_fb_xrgb8888_to_rgb888_dstclip(void *dst, unsigned int dst_pitch,
 	size_t pixels = (clip->x2 - clip->x1);
 	size_t lines = (clip->y2 - clip->y1);
 
-	convert_lines(dst + dst_offset, dst_pitch,
-		      vaddr + src_offset, fb->pitches[0],
-		      pixels, lines, conv);
+	convert_lines_toio(dst + dst_offset, dst_pitch,
+			   vaddr + src_offset, fb->pitches[0],
+			   pixels, lines, conv);
 }
 EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb888_dstclip);
 
-- 
2.18.1

Re: [PATCH 2/4] drm: use convert_lines() in xrgb8888_to_rgb565 helpers.

[Noralf Trønnes]

Den 09.04.2019 13.59, skrev Gerd Hoffmann:
> Also add two conversion functions for the swab / not swab cases.
> That way we have to check the swab flag only once.
> 
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  drivers/gpu/drm/drm_format_helper.c | 117 +++++++++++++++-------------
>  1 file changed, 62 insertions(+), 55 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_format_helper.c b/drivers/gpu/drm/drm_format_helper.c
> index f32e0173600c..b8d17cd0a9f8 100644
> --- a/drivers/gpu/drm/drm_format_helper.c
> +++ b/drivers/gpu/drm/drm_format_helper.c
> @@ -38,6 +38,46 @@ static struct drm_format_convert convert_swab16 = {
>  	.func = convert_swab16_fn,
>  };
>  
> +static void convert_xrgb8888_to_rgb565_fn(void *dst, void *src, u32 pixels)
> +{
> +	u32 *sbuf = src;
> +	u16 *dbuf = dst;
> +	u32 x;
> +
> +	for (x = 0; x < pixels; x++) {
> +		dbuf[x] = ((sbuf[x] & 0x00F80000) >> 8) |
> +			((sbuf[x] & 0x0000FC00) >> 5) |
> +			((sbuf[x] & 0x000000F8) >> 3);
> +	}
> +}
> +
> +static struct drm_format_convert convert_xrgb8888_to_rgb565 = {
> +	.dst_cpp = 2,
> +	.src_cpp = 4,
> +	.func = convert_xrgb8888_to_rgb565_fn,
> +};
> +
> +static void convert_xrgb8888_to_rgb565_swab_fn(void *dst, void *src, u32 pixels)
> +{
> +	u32 *sbuf = src;
> +	u16 *dbuf = dst;
> +	u16 val16;
> +	u32 x;
> +
> +	for (x = 0; x < pixels; x++) {
> +		val16 = ((sbuf[x] & 0x00F80000) >> 8) |
> +			((sbuf[x] & 0x0000FC00) >> 5) |
> +			((sbuf[x] & 0x000000F8) >> 3);
> +		dbuf[x] = swab16(val16);
> +	}
> +}
> +
> +static struct drm_format_convert convert_xrgb8888_to_rgb565_swap = {
> +	.dst_cpp = 2,
> +	.src_cpp = 4,
> +	.func = convert_xrgb8888_to_rgb565_swab_fn,
> +};
> +

I find that drm_format_convert makes the code more difficult to read.
The only shared code is the xrgb8888 to rgb565 conversion.

Can we do something like this instead:

static void drm_fb_xrgb8888_to_rgb565_line(u16 *dst, u32 *src, unsigned
int width, bool swap)
{
	unsigned int x;

	for (x = 0; x < width; x++) {
		u16 val = ((*src & 0x00F80000) >> 8) |
			  ((*src & 0x0000FC00) >> 5) |
			  ((*src & 0x000000F8) >> 3);
		src++;
		if (swap)
			*dst++ = swab16(val);
		else
			*dst++ = val;
	}
}

void drm_fb_xrgb8888_to_rgb565(void *dst, void *vaddr,
			       struct drm_framebuffer *fb,
			       struct drm_rect *clip, bool swap)
{
	void *src = vaddr + clip_offset(clip, fb->pitches[0], 4);
	unsigned width = clip->x2 - clip->x1;
	unsigned height = clip->y2 - clip->y1;
	size_t src_clip_pitch = width * 4;
	size_t dst_clip_pitch = width * 2;
	unsigned int y;
	void *sbuf;

	/*
	 * The cma memory is write-combined so reads are uncached.
	 * Speed up by fetching one line at a time.
	 */
	sbuf = kmalloc(src_clip_pitch, GFP_KERNEL);
	if (!sbuf)
		return;

	for (y = 0; y < height; y++) {
		memcpy(sbuf, src, src_clip_pitch);

		drm_fb_xrgb8888_to_rgb565_line(dst, sbuf, width, swap);

		src += fb->pitches[0];
		dst += dst_clip_pitch;
	}

	kfree(sbuf);
}
EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565);

void drm_fb_xrgb8888_to_rgb565_dstclip(void __iomem *dst,
				       unsigned int dst_pitch,
				       void *vaddr, struct drm_framebuffer *fb,
				       struct drm_rect *clip, bool swap)
{
	void *src = vaddr + clip_offset(clip, fb->pitches[0], 4);
	unsigned width = clip->x2 - clip->x1;
	unsigned height = clip->y2 - clip->y1;
	size_t dst_clip_pitch = width * 2;
	unsigned int y;
	void *dbuf;

	dst += clip_offset(clip, dst_pitch, 2);

	dbuf = kmalloc(dst_clip_pitch, GFP_KERNEL);
	if (!dbuf)
		return;

	for (y = 0; y < height; y++) {
		drm_fb_xrgb8888_to_rgb565_line(dbuf, src, width, swap);

		memcpy_toio(dst, dbuf, dst_clip_pitch);

		src += fb->pitches[0];
		dst += dst_pitch;
	}

	kfree(dbuf);
}
EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565_dstclip);


Other things I noticed:

drm_fb_memcpy() is just a wrapper around drm_fb_memcpy_lines() and
drm_fb_memcpy_dstclip() around drm_fb_memcpy_lines_toio(). They can be
merged.

checkpatch gave this:

WARNING: Use #include <linux/io.h> instead of <asm/io.h>
#50: FILE: drivers/gpu/drm/drm_format_helper.c:14:
+#include <asm/io.h>

Noralf.

>  static void convert_lines(void *dst, unsigned int dst_pitch,
>  			  void *src, unsigned int src_pitch,
>  			  unsigned int pixels,
> @@ -152,44 +192,6 @@ void drm_fb_swab16(u16 *dst, void *vaddr, struct drm_framebuffer *fb,
>  }
>  EXPORT_SYMBOL(drm_fb_swab16);
>  
> -static void drm_fb_xrgb8888_to_rgb565_lines(void *dst, unsigned int dst_pitch,
> -					    void *src, unsigned int src_pitch,
> -					    unsigned int src_linelength,
> -					    unsigned int lines,
> -					    bool swap)
> -{
> -	unsigned int linepixels = src_linelength / sizeof(u32);
> -	unsigned int x, y;
> -	u32 *sbuf;
> -	u16 *dbuf, val16;
> -
> -	/*
> -	 * The cma memory is write-combined so reads are uncached.
> -	 * Speed up by fetching one line at a time.
> -	 */
> -	sbuf = kmalloc(src_linelength, GFP_KERNEL);
> -	if (!sbuf)
> -		return;
> -
> -	for (y = 0; y < lines; y++) {
> -		memcpy(sbuf, src, src_linelength);
> -		dbuf = dst;
> -		for (x = 0; x < linepixels; x++) {
> -			val16 = ((sbuf[x] & 0x00F80000) >> 8) |
> -				((sbuf[x] & 0x0000FC00) >> 5) |
> -				((sbuf[x] & 0x000000F8) >> 3);
> -			if (swap)
> -				*dbuf++ = swab16(val16);
> -			else
> -				*dbuf++ = val16;
> -		}
> -		src += src_pitch;
> -		dst += dst_pitch;
> -	}
> -
> -	kfree(sbuf);
> -}
> -
>  /**
>   * drm_fb_xrgb8888_to_rgb565 - Convert XRGB8888 to RGB565 clip buffer
>   * @dst: RGB565 destination buffer
> @@ -208,15 +210,17 @@ void drm_fb_xrgb8888_to_rgb565(void *dst, void *vaddr,
>  			       struct drm_framebuffer *fb,
>  			       struct drm_rect *clip, bool swap)
>  {
> -	unsigned int src_offset = (clip->y1 * fb->pitches[0])
> -		+ (clip->x1 * sizeof(u32));
> -	size_t src_len = (clip->x2 - clip->x1) * sizeof(u32);
> -	size_t dst_len = (clip->x2 - clip->x1) * sizeof(u16);
> +	struct drm_format_convert *conv = swap
> +		? &convert_xrgb8888_to_rgb565_swap
> +		: &convert_xrgb8888_to_rgb565;
> +	unsigned int src_offset =
> +		clip_offset(clip, fb->pitches[0], conv->src_cpp);
> +	size_t pixels = (clip->x2 - clip->x1);
> +	size_t lines = (clip->y2 - clip->y1);
>  
> -	drm_fb_xrgb8888_to_rgb565_lines(dst, dst_len,
> -					vaddr + src_offset, fb->pitches[0],
> -					src_len, clip->y2 - clip->y1,
> -					swap);
> +	convert_lines(dst, pixels * conv->dst_cpp,
> +		      vaddr + src_offset, fb->pitches[0],
> +		      pixels, lines, conv);
>  }
>  EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565);
>  
> @@ -239,16 +243,19 @@ void drm_fb_xrgb8888_to_rgb565_dstclip(void *dst, unsigned int dst_pitch,
>  				       void *vaddr, struct drm_framebuffer *fb,
>  				       struct drm_rect *clip, bool swap)
>  {
> -	unsigned int src_offset = (clip->y1 * fb->pitches[0])
> -		+ (clip->x1 * sizeof(u32));
> -	unsigned int dst_offset = (clip->y1 * dst_pitch)
> -		+ (clip->x1 * sizeof(u16));
> -	size_t src_len = (clip->x2 - clip->x1) * sizeof(u32);
> +	struct drm_format_convert *conv = swap
> +		? &convert_xrgb8888_to_rgb565_swap
> +		: &convert_xrgb8888_to_rgb565;
> +	unsigned int src_offset =
> +		clip_offset(clip, fb->pitches[0], conv->src_cpp);
> +	unsigned int dst_offset =
> +		clip_offset(clip, dst_pitch, conv->dst_cpp);
> +	size_t pixels = (clip->x2 - clip->x1);
> +	size_t lines = (clip->y2 - clip->y1);
>  
> -	drm_fb_xrgb8888_to_rgb565_lines(dst + dst_offset, dst_pitch,
> -					vaddr + src_offset, fb->pitches[0],
> -					src_len, clip->y2 - clip->y1,
> -					swap);
> +	convert_lines(dst + dst_offset, dst_pitch,
> +		      vaddr + src_offset, fb->pitches[0],
> +		      pixels, lines, conv);
>  }
>  EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565_dstclip);
>  
>