Hi Am 29.06.20 um 10:40 schrieb Daniel Vetter: > On Thu, Jun 25, 2020 at 02:00:03PM +0200, Thomas Zimmermann wrote: >> The memcpy's destination buffer might have a different pitch than the >> source. Support different pitches as function argument. >> >> Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx> > > Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx> > > But I do have questions ... why did we allocate a source drm_framebuffer > with mismatching pitch? That sounds backwards, especially for simplekms. There's userspace that allocates framebuffers in tiles of 64x64 pixels. I think I've seen this with Gnome. So if you have a 800x600 display mode, the allocated framebuffer has a scanline pitch of 832 pixels and the final 32 pixels are ignored. In regular drivers, we can handle this with the VGA offset register [1] or some equivalent. That's obviously not an option with simplekms, so the different pitch is required. Best regards Thomas [1] https://web.stanford.edu/class/cs140/projects/pintos/specs/freevga/vga/crtcreg.htm#13 > > Would be good to add the reasons why we need this to the commit message, > I'm sure I'll discover it later on eventually. > -Daniel > >> --- >> drivers/gpu/drm/drm_format_helper.c | 9 +++++---- >> drivers/gpu/drm/mgag200/mgag200_mode.c | 2 +- >> drivers/gpu/drm/tiny/cirrus.c | 2 +- >> include/drm/drm_format_helper.h | 2 +- >> 4 files changed, 8 insertions(+), 7 deletions(-) >> >> diff --git a/drivers/gpu/drm/drm_format_helper.c b/drivers/gpu/drm/drm_format_helper.c >> index c043ca364c86..8d5a683afea7 100644 >> --- a/drivers/gpu/drm/drm_format_helper.c >> +++ b/drivers/gpu/drm/drm_format_helper.c >> @@ -52,6 +52,7 @@ EXPORT_SYMBOL(drm_fb_memcpy); >> /** >> * drm_fb_memcpy_dstclip - Copy clip buffer >> * @dst: Destination buffer (iomem) >> + * @dst_pitch: Number of bytes between two consecutive scanlines within dst >> * @vaddr: Source buffer >> * @fb: DRM framebuffer >> * @clip: Clip rectangle area to copy >> @@ -59,12 +60,12 @@ EXPORT_SYMBOL(drm_fb_memcpy); >> * 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_memcpy_dstclip(void __iomem *dst, void *vaddr, >> - struct drm_framebuffer *fb, >> +void drm_fb_memcpy_dstclip(void __iomem *dst, unsigned int dst_pitch, >> + void *vaddr, struct drm_framebuffer *fb, >> struct drm_rect *clip) >> { >> unsigned int cpp = fb->format->cpp[0]; >> - unsigned int offset = clip_offset(clip, fb->pitches[0], cpp); >> + unsigned int offset = clip_offset(clip, dst_pitch, cpp); >> size_t len = (clip->x2 - clip->x1) * cpp; >> unsigned int y, lines = clip->y2 - clip->y1; >> >> @@ -73,7 +74,7 @@ void drm_fb_memcpy_dstclip(void __iomem *dst, void *vaddr, >> for (y = 0; y < lines; y++) { >> memcpy_toio(dst, vaddr, len); >> vaddr += fb->pitches[0]; >> - dst += fb->pitches[0]; >> + dst += dst_pitch; >> } >> } >> EXPORT_SYMBOL(drm_fb_memcpy_dstclip); >> diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c >> index f16bd278ab7e..7d4f3a62d885 100644 >> --- a/drivers/gpu/drm/mgag200/mgag200_mode.c >> +++ b/drivers/gpu/drm/mgag200/mgag200_mode.c >> @@ -1586,7 +1586,7 @@ mgag200_handle_damage(struct mga_device *mdev, struct drm_framebuffer *fb, >> if (drm_WARN_ON(dev, !vmap)) >> return; /* BUG: SHMEM BO should always be vmapped */ >> >> - drm_fb_memcpy_dstclip(mdev->vram, vmap, fb, clip); >> + drm_fb_memcpy_dstclip(mdev->vram, fb->pitches[0], vmap, fb, clip); >> >> drm_gem_shmem_vunmap(fb->obj[0], vmap); >> >> diff --git a/drivers/gpu/drm/tiny/cirrus.c b/drivers/gpu/drm/tiny/cirrus.c >> index 744a8e337e41..2dd9e5e31e3d 100644 >> --- a/drivers/gpu/drm/tiny/cirrus.c >> +++ b/drivers/gpu/drm/tiny/cirrus.c >> @@ -327,7 +327,7 @@ static int cirrus_fb_blit_rect(struct drm_framebuffer *fb, >> goto out_dev_exit; >> >> if (cirrus->cpp == fb->format->cpp[0]) >> - drm_fb_memcpy_dstclip(cirrus->vram, >> + drm_fb_memcpy_dstclip(cirrus->vram, fb->pitches[0], >> vmap, fb, rect); >> >> else if (fb->format->cpp[0] == 4 && cirrus->cpp == 2) >> diff --git a/include/drm/drm_format_helper.h b/include/drm/drm_format_helper.h >> index 5f9e37032468..2b5036a5fbe7 100644 >> --- a/include/drm/drm_format_helper.h >> +++ b/include/drm/drm_format_helper.h >> @@ -11,7 +11,7 @@ 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 __iomem *dst, void *vaddr, >> +void drm_fb_memcpy_dstclip(void __iomem *dst, unsigned int dst_pitch, void *vaddr, >> struct drm_framebuffer *fb, >> struct drm_rect *clip); >> void drm_fb_swab(void *dst, void *src, struct drm_framebuffer *fb, >> -- >> 2.27.0 >> > -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Felix Imendörffer
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