Den 22.10.2021 15.28, skrev Thomas Zimmermann:
> Move destination-buffer clipping from all format-helper conversion
> functions into callers. Support destination-buffer pitch. Only
> distinguish between system and I/O memory, but use same logic
> everywhere.
>
> Simply harmonize the interface and semantics of the existing code.
> Not all conversion helpers support all combinations of parameters.
> We have to add additional features when we need them.
>
> Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
> ---
> /**
> * drm_fb_xrgb8888_to_gray8 - Convert XRGB8888 to grayscale
> * @dst: 8-bit grayscale destination buffer
> + * @dst_pitch: Number of bytes between two consecutive scanlines within dst
> * @vaddr: XRGB8888 source buffer
> * @fb: DRM framebuffer
> * @clip: Clip rectangle area to copy
> @@ -415,16 +417,21 @@ EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb888_dstclip);
> *
> * ITU BT.601 is used for the RGB -> luma (brightness) conversion.
> */
> -void drm_fb_xrgb8888_to_gray8(u8 *dst, void *vaddr, struct drm_framebuffer *fb,
> - struct drm_rect *clip)
> +void drm_fb_xrgb8888_to_gray8(void *dst, unsigned int dst_pitch, const void *vaddr,
> + const struct drm_framebuffer *fb, const struct drm_rect *clip)
> {
> unsigned int len = (clip->x2 - clip->x1) * sizeof(u32);
> unsigned int x, y;
> void *buf;
> - u32 *src;
> + u8 *dst8;
> + u32 *src32;
>
> if (WARN_ON(fb->format->format != DRM_FORMAT_XRGB8888))
> return;
> +
> + if (!dst_pitch)
len is source length (should really have been named src_len) which
results in a kernel crash:
> + dst_pitch = len;
This works:
dst_pitch = drm_rect_width(clip);
With that fixed:
Tested-by: Noralf Trønnes <noralf@xxxxxxxxxxx>
Reviewed-by: Noralf Trønnes <noralf@xxxxxxxxxxx>
> +
> /*
> * The cma memory is write-combined so reads are uncached.
> * Speed up by fetching one line at a time.
> @@ -433,20 +440,22 @@ void drm_fb_xrgb8888_to_gray8(u8 *dst, void *vaddr, struct drm_framebuffer *fb,
> if (!buf)
> return;
>
> + vaddr += clip_offset(clip, fb->pitches[0], sizeof(u32));
> for (y = clip->y1; y < clip->y2; y++) {
> - src = vaddr + (y * fb->pitches[0]);
> - src += clip->x1;
> - memcpy(buf, src, len);
> - src = buf;
> + dst8 = dst;
> + src32 = memcpy(buf, vaddr, len);
> for (x = clip->x1; x < clip->x2; x++) {
> - u8 r = (*src & 0x00ff0000) >> 16;
> - u8 g = (*src & 0x0000ff00) >> 8;
> - u8 b = *src & 0x000000ff;
> + u8 r = (*src32 & 0x00ff0000) >> 16;
> + u8 g = (*src32 & 0x0000ff00) >> 8;
> + u8 b = *src32 & 0x000000ff;
>
> /* ITU BT.601: Y = 0.299 R + 0.587 G + 0.114 B */
> - *dst++ = (3 * r + 6 * g + b) / 10;
> - src++;
> + *dst8++ = (3 * r + 6 * g + b) / 10;
> + src32++;
> }
> +
> + vaddr += fb->pitches[0];
> + dst += dst_pitch;
> }
>
> kfree(buf);
