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dmarc=fail (p=none dis=none) header.from=raspberrypi.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id AD3496E53E; Wed, 29 Jul 2020 14:46:16 +0000 (UTC) Received: from mail-wm1-x343.google.com (mail-wm1-x343.google.com [IPv6:2a00:1450:4864:20::343]) by gabe.freedesktop.org (Postfix) with ESMTPS id 033FC6E527 for ; Wed, 29 Jul 2020 14:46:15 +0000 (UTC) Received: by mail-wm1-x343.google.com with SMTP id d190so2958605wmd.4 for ; Wed, 29 Jul 2020 07:46:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=raspberrypi.com; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=3iyFpM5/BXg/ovW1sf4meruZ9t5/ZCB/YXrufU01eIM=; b=dEkb4hGGoi60zjTJt0jGB+G3PDfjSdeL573SQ9ZlTLlJpbzG1mvzCSBPrSHaxFWnHq wesmd8C4xEWXcwAD1Ofb4i9NEiD0kjobimkh8lNMT9P7zphud59M7gvsf8rI5o+/IJSU MrAngD03i3HCsyt1Txo66Vf05UVhTcKOoix5sObcfZxIe1Lu0X16HuAqOm7PFHcOyyn9 IlFo3DYouLlgCOXmEcZXqNVlVopPHNoQptmn8p1/GsNEbwE2oXZFBGVupjZCh3ouCWrD x01FzIMzGrNJkedjSqdos6FURUez3YonBiw2dRVOvO/TXWYZG67ueiYM2ONC0XXo2vJL axcA== X-Google-DKIM-Signature: v=1; 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charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Wed, 29 Jul 2020 at 15:42, Maxime Ripard wrote: > > Hi, > > On Wed, Jul 29, 2020 at 03:09:21PM +0100, Dave Stevenson wrote: > > On Wed, 8 Jul 2020 at 18:43, Maxime Ripard wrote: > > > > > > In order to avoid pixels getting stuck in the (unflushable) FIFO between > > > the HVS and the PV, we need to add some delay after disabling the PV output > > > and before disabling the HDMI controller. 20ms seems to be good enough so > > > let's use that. > > > > > > Signed-off-by: Maxime Ripard > > > --- > > > drivers/gpu/drm/vc4/vc4_crtc.c | 2 ++ > > > 1 file changed, 2 insertions(+) > > > > > > diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c > > > index d0b326e1df0a..7b178d67187f 100644 > > > --- a/drivers/gpu/drm/vc4/vc4_crtc.c > > > +++ b/drivers/gpu/drm/vc4/vc4_crtc.c > > > @@ -403,6 +403,8 @@ static void vc4_crtc_atomic_disable(struct drm_crtc *crtc, > > > ret = wait_for(!(CRTC_READ(PV_V_CONTROL) & PV_VCONTROL_VIDEN), 1); > > > WARN_ONCE(ret, "Timeout waiting for !PV_VCONTROL_VIDEN\n"); > > > > > > + mdelay(20); > > > > mdelay for 20ms seems a touch unfriendly as it's a busy wait. Can we > > not msleep instead? > > Since the timing was fairly critical, sleeping didn't seem like a good > solution since there's definitely some chance you overshoot and end up > with a higher time than the one you targeted. Fair enough. I know timing is "entertaining" around some of the 2711 pipeline setup. Reviewed-by: Dave Stevenson _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel