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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 3D381C4743F for ; Fri, 4 Jun 2021 17:26:53 +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 EF46561414 for ; Fri, 4 Jun 2021 17:26:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EF46561414 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.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 0AEC76F648; Fri, 4 Jun 2021 17:26:52 +0000 (UTC) Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by gabe.freedesktop.org (Postfix) with ESMTPS id 112CF6F645; Fri, 4 Jun 2021 17:26:51 +0000 (UTC) IronPort-SDR: tWTVzyjj1JsqHL1upD1hPHNyRx1vZ4ucYw/hh11+rYmTLx6kdaOhtftozK/F2BShTVZ7Z1LLMG ENjT0baCPo+w== X-IronPort-AV: E=McAfee;i="6200,9189,10005"; a="184705800" X-IronPort-AV: E=Sophos;i="5.83,248,1616482800"; d="scan'208";a="184705800" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Jun 2021 10:26:50 -0700 IronPort-SDR: hHxfs9zcgC2O6PZrXBqdGq+eSyydodxVXZvXVI2bKozhgASgx9bBU8+ndopyiwkqxP9Y2HmPs8 GPnpR/h35PpQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.83,248,1616482800"; d="scan'208";a="439257354" Received: from stinkbox.fi.intel.com (HELO stinkbox) ([10.237.72.171]) by orsmga007.jf.intel.com with SMTP; 04 Jun 2021 10:26:44 -0700 Received: by stinkbox (sSMTP sendmail emulation); Fri, 04 Jun 2021 20:26:44 +0300 Date: Fri, 4 Jun 2021 20:26:44 +0300 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Werner Sembach Subject: Re: [PATCH 2/4] drm/uAPI: Add "active bpc" as feedback channel for "max bpc" drm property Message-ID: References: <20210604171723.10276-1-wse@tuxedocomputers.com> <20210604171723.10276-3-wse@tuxedocomputers.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20210604171723.10276-3-wse@tuxedocomputers.com> X-Patchwork-Hint: comment 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: amd-gfx@lists.freedesktop.org, tzimmermann@suse.de, intel-gfx@lists.freedesktop.org, sunpeng.li@amd.com, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, airlied@linux.ie, rodrigo.vivi@intel.com, alexander.deucher@amd.com, christian.koenig@amd.com Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Fri, Jun 04, 2021 at 07:17:21PM +0200, Werner Sembach wrote: > Add a new general drm property "active bpc" which can be used by graphic drivers > to report the applied bit depth per pixel back to userspace. > > While "max bpc" can be used to change the color depth, there was no way to check > which one actually got used. While in theory the driver chooses the best/highest > color depth within the max bpc setting a user might not be fully aware what his > hardware is or isn't capable off. This is meant as a quick way to double check > the setup. > > In the future, automatic color calibration for screens might also depend on this > information available. > > Signed-off-by: Werner Sembach > --- > drivers/gpu/drm/drm_atomic_uapi.c | 2 ++ > drivers/gpu/drm/drm_connector.c | 40 +++++++++++++++++++++++++++++++ > include/drm/drm_connector.h | 15 ++++++++++++ > 3 files changed, 57 insertions(+) > > diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c > index 268bb69c2e2f..7ae4e40936b5 100644 > --- a/drivers/gpu/drm/drm_atomic_uapi.c > +++ b/drivers/gpu/drm/drm_atomic_uapi.c > @@ -873,6 +873,8 @@ drm_atomic_connector_get_property(struct drm_connector *connector, > *val = 0; > } else if (property == connector->max_bpc_property) { > *val = state->max_requested_bpc; > + } else if (property == connector->active_bpc_property) { > + *val = state->active_bpc; > } else if (connector->funcs->atomic_get_property) { > return connector->funcs->atomic_get_property(connector, > state, property, val); > diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c > index 7631f76e7f34..5f42a5be5822 100644 > --- a/drivers/gpu/drm/drm_connector.c > +++ b/drivers/gpu/drm/drm_connector.c > @@ -1195,6 +1195,13 @@ static const struct drm_prop_enum_list dp_colorspaces[] = { > * drm_connector_attach_max_bpc_property() to create and attach the > * property to the connector during initialization. > * > + * active bpc: > + * This read-only range property is used by userspace check the bit depth > + * actually applied by the GPU driver after evaluation all hardware > + * capabilities and max bpc. Drivers to use the function > + * drm_connector_attach_active_bpc_property() to create and attach the > + * property to the connector during initialization. > + * > * Connectors also have one standardized atomic property: > * > * CRTC_ID: > @@ -2150,6 +2157,39 @@ int drm_connector_attach_max_bpc_property(struct drm_connector *connector, > } > EXPORT_SYMBOL(drm_connector_attach_max_bpc_property); > > +/** > + * drm_connector_attach_active_bpc_property - attach "active bpc" property > + * @connector: connector to attach active bpc property on. > + * @min: The minimum bit depth supported by the connector. > + * @max: The maximum bit depth supported by the connector. > + * > + * This is used to check the applied bit depth on a connector. > + * > + * Returns: > + * Zero on success, negative errno on failure. > + */ > +int drm_connector_attach_active_bpc_property(struct drm_connector *connector, > + int min, int max) > +{ > + struct drm_device *dev = connector->dev; > + struct drm_property *prop; > + > + prop = connector->active_bpc_property; > + if (!prop) { > + prop = drm_property_create_range(dev, 0, "active bpc", min, max); Should be immutable. Also wondering what the semantics of this should be when eg. DSC is active? > + if (!prop) > + return -ENOMEM; > + > + connector->active_bpc_property = prop; > + } > + > + drm_object_attach_property(&connector->base, prop, 0); > + connector->state->active_bpc = 0; > + > + return 0; > +} > +EXPORT_SYMBOL(drm_connector_attach_active_bpc_property); > + > /** > * drm_connector_set_vrr_capable_property - sets the variable refresh rate > * capable property for a connector > diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h > index 1922b278ffad..c58cba2b6afe 100644 > --- a/include/drm/drm_connector.h > +++ b/include/drm/drm_connector.h > @@ -781,6 +781,13 @@ struct drm_connector_state { > */ > u8 max_bpc; > > + /** > + * @active_bpc: Read only property set by the GPU driver to the actually > + * applied bit depth of the pixels after evaluating all hardware > + * limitations. > + */ > + u8 active_bpc; > + > /** > * @hdr_output_metadata: > * DRM blob property for HDR output metadata > @@ -1380,6 +1387,12 @@ struct drm_connector { > */ > struct drm_property *max_bpc_property; > > + /** > + * @active_bpc_property: Default connector property for the active bpc > + * to be driven out of the connector. > + */ > + struct drm_property *active_bpc_property; > + > #define DRM_CONNECTOR_POLL_HPD (1 << 0) > #define DRM_CONNECTOR_POLL_CONNECT (1 << 1) > #define DRM_CONNECTOR_POLL_DISCONNECT (1 << 2) > @@ -1698,6 +1711,8 @@ int drm_connector_set_panel_orientation_with_quirk( > int width, int height); > int drm_connector_attach_max_bpc_property(struct drm_connector *connector, > int min, int max); > +int drm_connector_attach_active_bpc_property(struct drm_connector *connector, > + int min, int max); > > /** > * struct drm_tile_group - Tile group metadata > -- > 2.25.1 -- Ville Syrjälä Intel