Add XRGB8888 emulation support for devices that can only do XRGB2101010.
This is chiefly useful for simpledrm on Apple devices where the
bootloader-provided framebuffer is 10-bit, which already works fine with
simplefb. This is required to make simpledrm support this too.
Signed-off-by: Hector Martin <mar...@marcan.st>
---
drivers/gpu/drm/drm_format_helper.c | 64 +++++++++++++++++++++++++++++
include/drm/drm_format_helper.h | 4 ++
2 files changed, 68 insertions(+)
diff --git a/drivers/gpu/drm/drm_format_helper.c
b/drivers/gpu/drm/drm_format_helper.c
index 69fde60e36b3..5998e57d6ff2 100644
--- a/drivers/gpu/drm/drm_format_helper.c
+++ b/drivers/gpu/drm/drm_format_helper.c
@@ -378,6 +378,60 @@ void drm_fb_xrgb8888_to_rgb888_dstclip(void __iomem *dst,
unsigned int dst_pitch
}
EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb888_dstclip);
+static void drm_fb_xrgb8888_to_xrgb2101010_line(u32 *dbuf, u32 *sbuf,
+ unsigned int pixels)
+{
+ unsigned int x;
+
+ for (x = 0; x < pixels; x++) {
+ *dbuf++ = ((sbuf[x] & 0x000000FF) << 2) |
+ ((sbuf[x] & 0x0000FF00) << 4) |
+ ((sbuf[x] & 0x00FF0000) << 6);
+ }
+}
+
+/**
+ * drm_fb_xrgb8888_to_xrgb2101010_dstclip - Convert XRGB8888 to XRGB2101010
clip
+ * buffer
+ * @dst: XRGB2101010 destination buffer (iomem)
+ * @dst_pitch: destination buffer pitch
+ * @vaddr: XRGB8888 source buffer
+ * @fb: DRM framebuffer
+ * @clip: Clip rectangle area to copy
+ *
+ * Drivers can use this function for XRGB2101010 devices that don't natively
+ * support XRGB8888.
+ *
+ * This function applies clipping on dst, i.e. the destination is a
+ * full (iomem) framebuffer but only the clip rect content is copied over.
+ */
+void drm_fb_xrgb8888_to_xrgb2101010_dstclip(void __iomem *dst,
+ unsigned int dst_pitch, void *vaddr,
+ struct drm_framebuffer *fb,
+ struct drm_rect *clip)
+{
+ size_t linepixels = clip->x2 - clip->x1;
+ size_t dst_len = linepixels * 4;
+ unsigned int y, lines = clip->y2 - clip->y1;
+ void *dbuf;
+
+ dbuf = kmalloc(dst_len, GFP_KERNEL);
+ if (!dbuf)
+ return;
+
+ vaddr += clip_offset(clip, fb->pitches[0], sizeof(u32));
+ dst += clip_offset(clip, dst_pitch, sizeof(u32));
+ for (y = 0; y < lines; y++) {
+ drm_fb_xrgb8888_to_xrgb2101010_line(dbuf, vaddr, linepixels);
+ memcpy_toio(dst, dbuf, dst_len);
+ vaddr += fb->pitches[0];
+ dst += dst_pitch;
+ }
+
+ kfree(dbuf);
+}
+EXPORT_SYMBOL(drm_fb_xrgb8888_to_xrgb2101010_dstclip);
+
/**
* drm_fb_xrgb8888_to_gray8 - Convert XRGB8888 to grayscale
* @dst: 8-bit grayscale destination buffer
@@ -464,6 +518,10 @@ int drm_fb_blit_rect_dstclip(void __iomem *dst, unsigned
int dst_pitch,
fb_format = DRM_FORMAT_XRGB8888;
if (dst_format == DRM_FORMAT_ARGB8888)
dst_format = DRM_FORMAT_XRGB8888;
+ if (fb_format == DRM_FORMAT_ARGB2101010)
+ fb_format = DRM_FORMAT_XRGB2101010;
+ if (dst_format == DRM_FORMAT_ARGB2101010)
+ dst_format = DRM_FORMAT_XRGB2101010;
if (dst_format == fb_format) {
drm_fb_memcpy_dstclip(dst, dst_pitch, vmap, fb, clip);
@@ -482,6 +540,12 @@ int drm_fb_blit_rect_dstclip(void __iomem *dst, unsigned
int dst_pitch,
vmap, fb, clip);
return 0;
}
+ } else if (dst_format == DRM_FORMAT_XRGB2101010) {
+ if (fb_format == DRM_FORMAT_XRGB8888) {
+ drm_fb_xrgb8888_to_xrgb2101010_dstclip(dst, dst_pitch,
+ vmap, fb, clip);
+ return 0;
+ }
}
return -EINVAL;
diff --git a/include/drm/drm_format_helper.h b/include/drm/drm_format_helper.h
index e86925cf07b9..a0faa710878b 100644
--- a/include/drm/drm_format_helper.h
+++ b/include/drm/drm_format_helper.h
@@ -29,6 +29,10 @@ void drm_fb_xrgb8888_to_rgb888(void *dst, void *src, struct
drm_framebuffer *fb,
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_xrgb2101010_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,
struct drm_rect *clip);
--
2.33.0
