From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4E682C2D0DB for ; Wed, 22 Jan 2020 08:31:46 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2058B24655 for ; Wed, 22 Jan 2020 08:31:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="Sft5dCWI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2058B24655 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ffwll.ch 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 A2F4B89AC3; Wed, 22 Jan 2020 08:31:44 +0000 (UTC) Received: from mail-wm1-x342.google.com (mail-wm1-x342.google.com [IPv6:2a00:1450:4864:20::342]) by gabe.freedesktop.org (Postfix) with ESMTPS id 7F15489AC3 for ; Wed, 22 Jan 2020 08:31:43 +0000 (UTC) Received: by mail-wm1-x342.google.com with SMTP id p17so6196782wmb.0 for ; Wed, 22 Jan 2020 00:31:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=vETm/cqCDdvu8YgJ91D8ovTzZmiZ5bghni5xOlGJa50=; b=Sft5dCWICznPBdMLL1VP3xutOvmmI3zIZgFi/qdZISt6LRrNscYorefEQHLmYYRqKZ KWT4w5opqDO9q1wJ/VME8d/ENGgll01J2LRNIXjHL/OZHCcKtF46ZGASluDEo5y65SYF ATntM9icj+qqTQKmpkuGxqOEMJWaRDDP2qOnY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=vETm/cqCDdvu8YgJ91D8ovTzZmiZ5bghni5xOlGJa50=; b=l+l6YEIycmpU7+YqcsmBF5+NL+ODZGYrWk87vpMxuDzHBim9/q+gV5AQF1RBVnB3HN qkNIQTPeJC6aywGVLfTMBfKxKP2oXZjexN6G99pOD8mka7hd4DOXU7NeeXPSc512GLdC FzCdZrHtE8kPGtz1FSluwjFtN/6TeuN7nEL8gIV9VNfKpoWJCcw+NbGw5ajEs2py52Lj DBSQ686g8V2PZzQyR4LW1ajRI/koUBGy6IqC8jsKMCLHCe9UKzc1foOGLNx8QVcQiT70 bRT9JICPeSnh4L78N8dhg5YNYD9NRglw+B7z+HOyqKFbF9Jsg5afV6ttpXsDCzgSHJwk 0N4g== X-Gm-Message-State: APjAAAXhOMD51pYHRnUXx+z4IiSPrN/Yr9JiHpivqPB3kWz9VRqIlByL LWOmZywShS5vqECCAogihjuLieI1OEgz4A== X-Google-Smtp-Source: APXvYqyGHGDtB9jvhm0wcfvsN8ff+Y7NBcqJOhea2NMz8SRwNiCQCQfPW7Aub5jBelErwtQJogOSOQ== X-Received: by 2002:a1c:f218:: with SMTP id s24mr1749861wmc.128.1579681902143; Wed, 22 Jan 2020 00:31:42 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id g7sm55799243wrq.21.2020.01.22.00.31.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 22 Jan 2020 00:31:41 -0800 (PST) Date: Wed, 22 Jan 2020 09:31:39 +0100 From: Daniel Vetter To: Thomas Zimmermann Subject: Re: [PATCH v3 1/4] drm: Add drm_crtc_has_vblank() Message-ID: <20200122083139.GP43062@phenom.ffwll.local> References: <20200120122051.25178-1-tzimmermann@suse.de> <20200120122051.25178-2-tzimmermann@suse.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200120122051.25178-2-tzimmermann@suse.de> X-Operating-System: Linux phenom 5.3.0-3-amd64 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: david@lechnology.com, oleksandr_andrushchenko@epam.com, airlied@linux.ie, sam@ravnborg.org, dri-devel@lists.freedesktop.org, virtualization@lists.linux-foundation.org, hdegoede@redhat.com, kraxel@redhat.com, xen-devel@lists.xenproject.org, emil.velikov@collabora.com, sean@poorly.run, laurent.pinchart@ideasonboard.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Mon, Jan 20, 2020 at 01:20:48PM +0100, Thomas Zimmermann wrote: > The new interface drm_crtc_has_vblank() return true if vblanking has > been initialized for a certain CRTC, or false otherwise. This function > will be useful for initializing CRTC state. > > Signed-off-by: Thomas Zimmermann > --- > drivers/gpu/drm/drm_vblank.c | 21 +++++++++++++++++++++ > include/drm/drm_vblank.h | 1 + > 2 files changed, 22 insertions(+) > > diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c > index 1659b13b178c..c20102899411 100644 > --- a/drivers/gpu/drm/drm_vblank.c > +++ b/drivers/gpu/drm/drm_vblank.c > @@ -501,6 +501,27 @@ int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs) > } > EXPORT_SYMBOL(drm_vblank_init); > > +/** > + * drm_crtc_has_vblank - test if vblanking has been initialized for > + * a CRTC > + * @crtc: the CRTC > + * > + * Drivers may call this function to test if vblank support is > + * initialized for a CRTC. For most hardware this means that vblanking > + * can also be enabled on the CRTC. > + * > + * Returns: > + * True if vblanking has been initialized for the given CRTC, false > + * otherwise. > + */ > +bool drm_crtc_has_vblank(const struct drm_crtc *crtc) So making this specific to a CRTC sounds like a good idea. But it's not the reality, drm_vblank.c assumes that either everything or nothing supports vblanks. The reason for dev->num_crtcs is historical baggage, it predates kms by a few years. For kms drivers the only two valid values are either 0 or dev->mode_config.num_crtcs. Yes that's an entire different can of worms that's been irking me since forever (ideally drm_vblank_init would somehow loose the num_crtcs argument for kms drivers, but some drivers call this before they've done all the drm_crtc_init calls so it's complicated). Hence drm_dev_has_vblank as I suggested. That would also allow you to replace a bunch of if (dev->num_crtcs) checks in drm_vblank.c, which should help quite a bit in code readability. Cheers, Daniel > +{ > + struct drm_device *dev = crtc->dev; > + > + return crtc->index < dev->num_crtcs; > +} > +EXPORT_SYMBOL(drm_crtc_has_vblank); > + > /** > * drm_crtc_vblank_waitqueue - get vblank waitqueue for the CRTC > * @crtc: which CRTC's vblank waitqueue to retrieve > diff --git a/include/drm/drm_vblank.h b/include/drm/drm_vblank.h > index c16c44052b3d..531a6bc12b7e 100644 > --- a/include/drm/drm_vblank.h > +++ b/include/drm/drm_vblank.h > @@ -206,6 +206,7 @@ struct drm_vblank_crtc { > }; > > int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs); > +bool drm_crtc_has_vblank(const struct drm_crtc *crtc); > u64 drm_crtc_vblank_count(struct drm_crtc *crtc); > u64 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc, > ktime_t *vblanktime); > -- > 2.24.1 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel