[PATCH] drm/format-helper: Split off byte swapping from drm_fb_xrgb8888_to_rgb565()
Thomas Zimmermann
tzimmermann at suse.de
Wed Jun 25 11:48:22 UTC 2025
Move big-endian support from drm_fb_xrgb8888_to_rgb565() into the new
helper drm_xrgb8888_to_rgb565be(). The functionality is required for
displays with big-endian byte order. Update all callers.
With the change applied, drm_fb_xrgb8888_to_rgb565() has the same
signature as the other conversion functions, which is required for
further updates to drm_fb_blit(). Also makes the format-conversion
helper available to panic handlers, if necessary.
Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
---
drivers/gpu/drm/drm_format_helper.c | 66 ++++++++++++-------
drivers/gpu/drm/drm_format_internal.h | 6 ++
drivers/gpu/drm/drm_mipi_dbi.c | 8 ++-
drivers/gpu/drm/gud/gud_pipe.c | 9 ++-
.../gpu/drm/tests/drm_format_helper_test.c | 8 +--
include/drm/drm_format_helper.h | 6 +-
6 files changed, 71 insertions(+), 32 deletions(-)
diff --git a/drivers/gpu/drm/drm_format_helper.c b/drivers/gpu/drm/drm_format_helper.c
index 99d9f7bbc261..8f3daf38ca63 100644
--- a/drivers/gpu/drm/drm_format_helper.c
+++ b/drivers/gpu/drm/drm_format_helper.c
@@ -559,18 +559,6 @@ static void drm_fb_xrgb8888_to_rgb565_line(void *dbuf, const void *sbuf, unsigne
drm_fb_xfrm_line_32to16(dbuf, sbuf, pixels, drm_pixel_xrgb8888_to_rgb565);
}
-static __always_inline u32 drm_xrgb8888_to_rgb565_swab(u32 pix)
-{
- return swab16(drm_pixel_xrgb8888_to_rgb565(pix));
-}
-
-/* TODO: implement this helper as conversion to RGB565|BIG_ENDIAN */
-static void drm_fb_xrgb8888_to_rgb565_swab_line(void *dbuf, const void *sbuf,
- unsigned int pixels)
-{
- drm_fb_xfrm_line_32to16(dbuf, sbuf, pixels, drm_xrgb8888_to_rgb565_swab);
-}
-
/**
* drm_fb_xrgb8888_to_rgb565 - Convert XRGB8888 to RGB565 clip buffer
* @dst: Array of RGB565 destination buffers
@@ -580,7 +568,6 @@ static void drm_fb_xrgb8888_to_rgb565_swab_line(void *dbuf, const void *sbuf,
* @fb: DRM framebuffer
* @clip: Clip rectangle area to copy
* @state: Transform and conversion state
- * @swab: Swap bytes
*
* 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
@@ -595,23 +582,56 @@ static void drm_fb_xrgb8888_to_rgb565_swab_line(void *dbuf, const void *sbuf,
*/
void drm_fb_xrgb8888_to_rgb565(struct iosys_map *dst, const unsigned int *dst_pitch,
const struct iosys_map *src, const struct drm_framebuffer *fb,
- const struct drm_rect *clip, struct drm_format_conv_state *state,
- bool swab)
+ const struct drm_rect *clip, struct drm_format_conv_state *state)
{
static const u8 dst_pixsize[DRM_FORMAT_MAX_PLANES] = {
2,
};
- void (*xfrm_line)(void *dbuf, const void *sbuf, unsigned int npixels);
+ drm_fb_xfrm(dst, dst_pitch, dst_pixsize, src, fb, clip, false, state,
+ drm_fb_xrgb8888_to_rgb565_line);
+}
+EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565);
+
+static void drm_fb_xrgb8888_to_rgb565be_line(void *dbuf, const void *sbuf,
+ unsigned int pixels)
+{
+ drm_fb_xfrm_line_32to16(dbuf, sbuf, pixels, drm_pixel_xrgb8888_to_rgb565be);
+}
- if (swab)
- xfrm_line = drm_fb_xrgb8888_to_rgb565_swab_line;
- else
- xfrm_line = drm_fb_xrgb8888_to_rgb565_line;
+/**
+ * drm_fb_xrgb8888_to_rgb565be - Convert XRGB8888 to RGB565|DRM_FORMAT_BIG_ENDIAN clip buffer
+ * @dst: Array of RGB565BE 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.
+ * @src: Array of XRGB8888 source buffer
+ * @fb: DRM framebuffer
+ * @clip: Clip rectangle area to copy
+ * @state: Transform and conversion state
+ *
+ * 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 @src 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 RGB565BE devices that don't support XRGB8888 natively.
+ */
+void drm_fb_xrgb8888_to_rgb565be(struct iosys_map *dst, const unsigned int *dst_pitch,
+ const struct iosys_map *src, const struct drm_framebuffer *fb,
+ const struct drm_rect *clip, struct drm_format_conv_state *state)
+{
+ static const u8 dst_pixsize[DRM_FORMAT_MAX_PLANES] = {
+ 2,
+ };
- drm_fb_xfrm(dst, dst_pitch, dst_pixsize, src, fb, clip, false, state, xfrm_line);
+ drm_fb_xfrm(dst, dst_pitch, dst_pixsize, src, fb, clip, false, state,
+ drm_fb_xrgb8888_to_rgb565be_line);
}
-EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565);
+EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565be);
static void drm_fb_xrgb8888_to_xrgb1555_line(void *dbuf, const void *sbuf, unsigned int pixels)
{
@@ -1188,7 +1208,7 @@ int drm_fb_blit(struct iosys_map *dst, const unsigned int *dst_pitch, uint32_t d
return 0;
} else if (fb_format == DRM_FORMAT_XRGB8888) {
if (dst_format == DRM_FORMAT_RGB565) {
- drm_fb_xrgb8888_to_rgb565(dst, dst_pitch, src, fb, clip, state, false);
+ drm_fb_xrgb8888_to_rgb565(dst, dst_pitch, src, fb, clip, state);
return 0;
} else if (dst_format == DRM_FORMAT_XRGB1555) {
drm_fb_xrgb8888_to_xrgb1555(dst, dst_pitch, src, fb, clip, state);
diff --git a/drivers/gpu/drm/drm_format_internal.h b/drivers/gpu/drm/drm_format_internal.h
index 9428d5cfebc5..ce29dd05bcc5 100644
--- a/drivers/gpu/drm/drm_format_internal.h
+++ b/drivers/gpu/drm/drm_format_internal.h
@@ -5,6 +5,7 @@
#include <linux/bits.h>
#include <linux/types.h>
+#include <linux/swab.h>
/*
* Each pixel-format conversion helper takes a raw pixel in a
@@ -59,6 +60,11 @@ static inline u32 drm_pixel_xrgb8888_to_rgb565(u32 pix)
((pix & 0x000000f8) >> 3);
}
+static inline u32 drm_pixel_xrgb8888_to_rgb565be(u32 pix)
+{
+ return swab16(drm_pixel_xrgb8888_to_rgb565(pix));
+}
+
static inline u32 drm_pixel_xrgb8888_to_rgbx5551(u32 pix)
{
return ((pix & 0x00f80000) >> 8) |
diff --git a/drivers/gpu/drm/drm_mipi_dbi.c b/drivers/gpu/drm/drm_mipi_dbi.c
index ba4be6be5d28..e33c78fc8fbd 100644
--- a/drivers/gpu/drm/drm_mipi_dbi.c
+++ b/drivers/gpu/drm/drm_mipi_dbi.c
@@ -230,7 +230,13 @@ int mipi_dbi_buf_copy(void *dst, struct iosys_map *src, struct drm_framebuffer *
case DRM_FORMAT_XRGB8888:
switch (dbidev->pixel_format) {
case DRM_FORMAT_RGB565:
- drm_fb_xrgb8888_to_rgb565(&dst_map, NULL, src, fb, clip, fmtcnv_state, swap);
+ if (swap) {
+ drm_fb_xrgb8888_to_rgb565be(&dst_map, NULL, src, fb, clip,
+ fmtcnv_state);
+ } else {
+ drm_fb_xrgb8888_to_rgb565(&dst_map, NULL, src, fb, clip,
+ fmtcnv_state);
+ }
break;
case DRM_FORMAT_RGB888:
drm_fb_xrgb8888_to_rgb888(&dst_map, NULL, src, fb, clip, fmtcnv_state);
diff --git a/drivers/gpu/drm/gud/gud_pipe.c b/drivers/gpu/drm/gud/gud_pipe.c
index adadd526641d..8d548d08f127 100644
--- a/drivers/gpu/drm/gud/gud_pipe.c
+++ b/drivers/gpu/drm/gud/gud_pipe.c
@@ -188,8 +188,13 @@ static int gud_prep_flush(struct gud_device *gdrm, struct drm_framebuffer *fb,
} else if (format->format == DRM_FORMAT_RGB332) {
drm_fb_xrgb8888_to_rgb332(&dst, NULL, src, fb, rect, fmtcnv_state);
} else if (format->format == DRM_FORMAT_RGB565) {
- drm_fb_xrgb8888_to_rgb565(&dst, NULL, src, fb, rect, fmtcnv_state,
- gud_is_big_endian());
+ if (gud_is_big_endian()) {
+ drm_fb_xrgb8888_to_rgb565be(&dst, NULL, src, fb, rect,
+ fmtcnv_state);
+ } else {
+ drm_fb_xrgb8888_to_rgb565(&dst, NULL, src, fb, rect,
+ fmtcnv_state);
+ }
} else if (format->format == DRM_FORMAT_RGB888) {
drm_fb_xrgb8888_to_rgb888(&dst, NULL, src, fb, rect, fmtcnv_state);
} else {
diff --git a/drivers/gpu/drm/tests/drm_format_helper_test.c b/drivers/gpu/drm/tests/drm_format_helper_test.c
index ad06762db671..7299fa8971ce 100644
--- a/drivers/gpu/drm/tests/drm_format_helper_test.c
+++ b/drivers/gpu/drm/tests/drm_format_helper_test.c
@@ -735,13 +735,13 @@ static void drm_test_fb_xrgb8888_to_rgb565(struct kunit *test)
NULL : &result->dst_pitch;
drm_fb_xrgb8888_to_rgb565(&dst, dst_pitch, &src, &fb, ¶ms->clip,
- &fmtcnv_state, false);
+ &fmtcnv_state);
buf = le16buf_to_cpu(test, (__force const __le16 *)buf, dst_size / sizeof(__le16));
KUNIT_EXPECT_MEMEQ(test, buf, result->expected, dst_size);
buf = dst.vaddr; /* restore original value of buf */
- drm_fb_xrgb8888_to_rgb565(&dst, &result->dst_pitch, &src, &fb, ¶ms->clip,
- &fmtcnv_state, true);
+ drm_fb_xrgb8888_to_rgb565be(&dst, &result->dst_pitch, &src, &fb, ¶ms->clip,
+ &fmtcnv_state);
buf = le16buf_to_cpu(test, (__force const __le16 *)buf, dst_size / sizeof(__le16));
KUNIT_EXPECT_MEMEQ(test, buf, result->expected_swab, dst_size);
@@ -749,7 +749,7 @@ static void drm_test_fb_xrgb8888_to_rgb565(struct kunit *test)
memset(buf, 0, dst_size);
drm_fb_xrgb8888_to_rgb565(&dst, dst_pitch, &src, &fb, ¶ms->clip,
- &fmtcnv_state, false);
+ &fmtcnv_state);
buf = le16buf_to_cpu(test, (__force const __le16 *)buf, dst_size / sizeof(__le16));
KUNIT_EXPECT_MEMEQ(test, buf, result->expected, dst_size);
}
diff --git a/include/drm/drm_format_helper.h b/include/drm/drm_format_helper.h
index 0d3ee2a1313f..562bc383ece4 100644
--- a/include/drm/drm_format_helper.h
+++ b/include/drm/drm_format_helper.h
@@ -82,8 +82,10 @@ void drm_fb_xrgb8888_to_rgb332(struct iosys_map *dst, const unsigned int *dst_pi
const struct drm_rect *clip, struct drm_format_conv_state *state);
void drm_fb_xrgb8888_to_rgb565(struct iosys_map *dst, const unsigned int *dst_pitch,
const struct iosys_map *src, const struct drm_framebuffer *fb,
- const struct drm_rect *clip, struct drm_format_conv_state *state,
- bool swab);
+ const struct drm_rect *clip, struct drm_format_conv_state *state);
+void drm_fb_xrgb8888_to_rgb565be(struct iosys_map *dst, const unsigned int *dst_pitch,
+ const struct iosys_map *src, const struct drm_framebuffer *fb,
+ const struct drm_rect *clip, struct drm_format_conv_state *state);
void drm_fb_xrgb8888_to_xrgb1555(struct iosys_map *dst, const unsigned int *dst_pitch,
const struct iosys_map *src, const struct drm_framebuffer *fb,
const struct drm_rect *clip, struct drm_format_conv_state *state);
--
2.50.0
More information about the dri-devel
mailing list