From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= Subject: Re: [RFCv1 03/12] drm: add DRM_MODE_PROP_DYNAMIC property flag Date: Mon, 7 Oct 2013 16:46:38 +0300 Message-ID: <20131007134638.GJ9395@intel.com> References: <1381020350-1125-1-git-send-email-robdclark@gmail.com> <1381020350-1125-4-git-send-email-robdclark@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by gabe.freedesktop.org (Postfix) with ESMTP id C57BFE7294 for ; Mon, 7 Oct 2013 06:47:01 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1381020350-1125-4-git-send-email-robdclark@gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dri-devel-bounces+sf-dri-devel=m.gmane.org@lists.freedesktop.org Errors-To: dri-devel-bounces+sf-dri-devel=m.gmane.org@lists.freedesktop.org To: Rob Clark Cc: dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org On Sat, Oct 05, 2013 at 08:45:41PM -0400, Rob Clark wrote: > This indicates to userspace that the property is something that can > be set dynamically without requiring a "test" step to check if the > hw is capable. This allows a userspace compositor, such as weston, > to avoid an extra ioctl to check whether it needs to fall-back to > GPU to composite some surface prior to submission of GPU render > commands. > --- > include/uapi/drm/drm_mode.h | 9 +++++++++ > 1 file changed, 9 insertions(+) > = > diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h > index 35921ba..15db837 100644 > --- a/include/uapi/drm/drm_mode.h > +++ b/include/uapi/drm/drm_mode.h > @@ -232,6 +232,15 @@ struct drm_mode_get_connector { > #define DRM_MODE_PROP_BLOB (1<<4) > #define DRM_MODE_PROP_BITMASK (1<<5) /* bitmask of enumerated types */ > #define DRM_MODE_PROP_OBJECT (1<<6) /* drm mode object */ > +/* Properties that are not dynamic cannot safely be changed without a > + * atomic-modeset / atomic-pageflip test step. But if userspace is > + * only changing dynamic properties, it is guaranteed that the change > + * will not exceed hw limits, so no test step is required. > + * > + * Note that fb_id properties are a bit ambiguous.. they of course can > + * be changed dynamically, assuming the pixel format does not change. > + */ > +#define DRM_MODE_PROP_DYNAMIC (1<<24) I'm still not convinced that this is useful. We can't even flag the FB ID with this flag since the FB encompasses stride/bpp/etc. parameters that for sure can't just be changed w/o first checking the new configuration. -- = Ville Syrj=E4l=E4 Intel OTC