[PATCH] drm: simple_kms_helper: Handle the vblank events

[Marek Vasut]

On 09/27/2016 02:16 PM, Noralf Trønnes wrote:
> 
> Den 27.09.2016 12:29, skrev Marek Vasut:
>> On 09/27/2016 09:49 AM, Daniel Vetter wrote:
>>> On Mon, Sep 26, 2016 at 2:59 PM, Marek Vasut <marex at denx.de> wrote:
>>>> On 09/26/2016 11:41 AM, Marek Vasut wrote:
>>>>> On 09/25/2016 11:00 PM, Daniel Vetter wrote:
>>>>>> On Sun, Sep 25, 2016 at 09:41:58PM +0200, Marek Vasut wrote:
>>>>>>> Handle the vblank events in the simple_kms_helper driver, otherwise
>>>>>>> the drm_atomic_helper flip_done event never happens.
>>>>>>>
>>>>>>> Signed-off-by: Marek Vasut <marex at denx.de>
>>>>>>> Cc: Noralf Trønnes <noralf at tronnes.org>
>>>>>>> Cc: Daniel Vetter <daniel at ffwll.ch>
>>>>>>> Cc: David Airlie <airlied at linux.ie>
>>>>>>> ---
>>>>>>>   drivers/gpu/drm/drm_simple_kms_helper.c | 18 ++++++++++++++++++
>>>>>>>   1 file changed, 18 insertions(+)
>>>>>>>
>>>>>>> diff --git a/drivers/gpu/drm/drm_simple_kms_helper.c
>>>>>>> b/drivers/gpu/drm/drm_simple_kms_helper.c
>>>>>>> index 7b6d26e..3345b40 100644
>>>>>>> --- a/drivers/gpu/drm/drm_simple_kms_helper.c
>>>>>>> +++ b/drivers/gpu/drm/drm_simple_kms_helper.c
>>>>>>> @@ -34,6 +34,23 @@ static const struct drm_encoder_funcs
>>>>>>> drm_simple_kms_encoder_funcs = {
>>>>>>>      .destroy = drm_encoder_cleanup,
>>>>>>>   };
>>>>>>>
>>>>>>> +static void drm_simple_kms_crtc_begin(struct drm_crtc *crtc,
>>>>>>> +                                 struct drm_crtc_state *state)
>>>>>>> +{
>>>>>>> +   struct drm_pending_vblank_event *event = crtc->state->event;
>>>>>>> +
>>>>>>> +   if (event) {
>>>>>>> +           crtc->state->event = NULL;
>>>>>>> +
>>>>>>> +           spin_lock_irq(&crtc->dev->event_lock);
>>>>>>> +           if (drm_crtc_vblank_get(crtc) == 0)
>>>>>>> +                   drm_crtc_arm_vblank_event(crtc, event);
>>>>>>> +           else
>>>>>>> +                   drm_crtc_send_vblank_event(crtc, event);
>>>>>>> +           spin_unlock_irq(&crtc->dev->event_lock);
>>>>>>> +   }
>>>>>>> +}
>>>>>> This should be done by drivers, in the ->update hook. At least if
>>>>>> we want
>>>>>> to pretend that it's semi-accurate and not racy (which the above is).
>>>>>> -Daniel
>>>>> Got it and wrapped into mxsfb, thanks.
>>>> Hrm, while this works most of the time, I managed to get a page_flip
>>>> timeout when terminating the kmscube OpenGL demo (see below). I'm not
>>>> getting this splat with this patch applied. Any idea what this could
>>>> mean ?
>>> Are you on latest drm-next?
>> No, I'm on next/master from 20160927 . Is this the right tree?
>> https://cgit.freedesktop.org/~airlied/linux/log/?h=drm-next
>>
>>> There was a bug fixed for 4.9 which
>>> resulted in the primary plane not always being added to the state,
>>> which means that the ->update hook would not get called when the plane
>>> is getting disabled.
>> Ah, which patch ?
> 
> I believe this is the one:
> 
> drm/simple-helpers: Always add planes to the state update
> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/drivers/gpu/drm/drm_simple_kms_helper.c?id=6dcf0de7ef10244b17442f47956a1d9fabe2abe1

Thanks. I have that one in my tree already.

-- 
Best regards,
Marek Vasut