Re: [PATCH v2] drm/atomic: Fix bookkeeping with TEST_ONLY, v2.

Maarten Lankhorst
2015-08-27T12:50:34Z

Op 27-08-15 om 14:48 schreef Ville Syrjälä:
> On Thu, Aug 27, 2015 at 02:43:35PM +0200, Maarten Lankhorst wrote:
>> Op 27-08-15 om 14:19 schreef Daniel Stone:
>>> Hi,
>>>
>>> On 4 August 2015 at 12:34, Maarten Lankhorst
>>> <maarten.lankhorst@linux.intel.com> wrote:
>>>> Commit ec9f932ed41622d120de52a5b525e4d77b9ef17e
>>>> "drm/atomic: Cleanup on error properly in the atomic ioctl."
>>>> cleaned up some error paths, but didn't fix the TEST_ONLY path.
>>>> In the check only case plane->fb shouldn't be updated, and
>>>> the vblank events should be cleared as on failure.
>>> Bikeshedding a bit ...
>>>
>>> An early test precludes TEST_ONLY | PAGE_FLIP_EVENT, so you don't need
>>> to mention this in the commit message; in this case, the main change
>>> is about plane->{,old_}fb.
>> Even testing with PAGE_FLIP_EVENT would be useful because
>> event && !crtc_state->active should not be allowed. In that case test
>> could succeed but commit could fail.
> Why would commit fail when the we're in DPMS off? I would suggest it
> should be allowed. The operation would just a be a nop from a HW point
> of view, all the calculation/checks would still be performed.
>
You can commit, just not with PAGE_FLIP_EVENT set when crtc is inactive.

~Maarten