[PATCH v5 5/9] drm: Extend framebuffer_check to handle formats with cpp/char_per_block 0

[Alexandru-Cosmin Gheorghe]

On Fri, Oct 19, 2018 at 02:21:46PM +0100, Brian Starkey wrote:
> Hi Alex,
> 
> On Fri, Oct 19, 2018 at 11:57:48AM +0100, Alexandru Gheorghe wrote:
> >For formats that are supported only with non-linear modifiers it
> >doesn't make to much sense to define cpp or char_per_block, so that
> >will be set to 0.
> >
> >This patch adds a restriction to force having a modifier attached when
> >cpp/char_per_block is 0, and to bypass checking the pitch restriction.
> >
> >This had been discussed here.
> >[1] https://people.freedesktop.org/~cbrill/dri-log/?channel=dri-devel&highlight_names=&date=2018-09-13&show_html=true
> >
> >Signed-off-by: Alexandru Gheorghe <alexandru-cosmin.gheorghe at arm.com>
> >---
> >drivers/gpu/drm/drm_framebuffer.c | 7 ++++++-
> >1 file changed, 6 insertions(+), 1 deletion(-)
> >
> >diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c
> >index 6aca8a1ccdb6..e346d0ad92e0 100644
> >--- a/drivers/gpu/drm/drm_framebuffer.c
> >+++ b/drivers/gpu/drm/drm_framebuffer.c
> >@@ -195,8 +195,13 @@ static int framebuffer_check(struct drm_device *dev,
> >	for (i = 0; i < info->num_planes; i++) {
> >		unsigned int width = fb_plane_width(r->width, info, i);
> >		unsigned int height = fb_plane_height(r->height, info, i);
> >+		unsigned int block_size = info->char_per_block[i];
> >		u64 min_pitch = drm_format_info_min_pitch(info, i, width);
> >
> >+		if (!block_size && (r->modifier[i] == DRM_FORMAT_MOD_LINEAR)) {
> >+			DRM_DEBUG_KMS("Format requires non-linear modifier for plane %d\n", i);
> >+			return -EINVAL;
> >+		}
> 
> You could probably move that blank like from Patch 2 to here ;-)
> Otherwise LGTM:

I blame rebase :)

> 
> Reviewed By: Brian Starkey <brian.starkey at arm.com>
> 
> >		if (!r->handles[i]) {
> >			DRM_DEBUG_KMS("no buffer object handle for plane %d\n", i);
> >			return -EINVAL;
> >@@ -208,7 +213,7 @@ static int framebuffer_check(struct drm_device *dev,
> >		if ((uint64_t) height * r->pitches[i] + r->offsets[i] > UINT_MAX)
> >			return -ERANGE;
> >
> >-		if (r->pitches[i] < min_pitch) {
> >+		if (block_size && r->pitches[i] < min_pitch) {
> >			DRM_DEBUG_KMS("bad pitch %u for plane %d\n", r->pitches[i], i);
> >			return -EINVAL;
> >		}
> >-- 
> >2.18.0
> >

-- 
Cheers,
Alex G