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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id D6D18ECAAD5 for ; Mon, 5 Sep 2022 17:45:10 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 6DB5410E472; Mon, 5 Sep 2022 17:45:09 +0000 (UTC) Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4096710E470 for ; Mon, 5 Sep 2022 17:45:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1662399903; x=1693935903; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=jjxT245GBGLeprBEGGJz1lzVLrTcYsg5rQ7Hc+SUXhU=; b=J3rET/1YgCjytuAuVSy7iunqGDgSswwMInk8erqhzsTLsDORdxt0zzO/ JE8noXnCsdI8Srf1DpJEWJPc7f0JVBs4onItZvZGUW2NA4L7yzsO5RCT/ nbfcVN64un8SC6iLjfOANzx3ze4sotC3KShYN3I+rDUE+S8YKin8nVnmh /QI20jPJBdTWbonDhuNmEagQTEQkSVpuOr+FhWIAaVwy32o/tUZcaVWZ3 CPLtCsjlZ53N4YiSdcUJ4POzzD1qDw1AXmv9lob+PnAAJDqBwhiy3tw1v XwvZpKH7TS6p0+51ng+PuVicwIWdoFjPgYy3m5bv4GIgcXrbF6qczscI4 Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10461"; a="382729578" X-IronPort-AV: E=Sophos;i="5.93,291,1654585200"; d="scan'208";a="382729578" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Sep 2022 10:45:02 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.93,291,1654585200"; d="scan'208";a="643874982" Received: from stinkpipe.fi.intel.com (HELO stinkbox) ([10.237.72.191]) by orsmga008.jf.intel.com with SMTP; 05 Sep 2022 10:44:59 -0700 Received: by stinkbox (sSMTP sendmail emulation); Mon, 05 Sep 2022 20:44:59 +0300 Date: Mon, 5 Sep 2022 20:44:59 +0300 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Andrzej Hajda Message-ID: References: <20220905080500.213330-1-andrzej.hajda@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Patchwork-Hint: comment Subject: Re: [Intel-gfx] [PATCH] drm/i915: do not reset PLANE_SURF on plane disable on older gens X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: intel-gfx@lists.freedesktop.org, Rodrigo Vivi Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Mon, Sep 05, 2022 at 07:02:40PM +0200, Andrzej Hajda wrote: > > > On 05.09.2022 13:48, Ville Syrjälä wrote: > > On Mon, Sep 05, 2022 at 10:05:00AM +0200, Andrzej Hajda wrote: > >> In case of ICL and older generations disabling plane and/or disabling > >> async update is always performed on vblank, > > It should only be broken on bdw-glk (see. need_async_flip_disable_wa). > > On CFL it is reported every drmtip run: > https://intel-gfx-ci.01.org/tree/drm-tip/drmtip.html?testfilter=tiled-max-hw > https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_1209/fi-cfl-8109u/igt@kms_big_fb@yf-tiled-max-hw-stride-32bpp-rotate-180-async-flip.html#dmesg-warnings402 > https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_1209/fi-cfl-8109u/igt@kms_big_fb@y-tiled-max-hw-stride-64bpp-rotate-180-async-flip.html#dmesg-warnings402 > https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_1209/fi-cfl-8109u/igt@kms_big_fb@y-tiled-max-hw-stride-32bpp-rotate-180-async-flip.html > https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_1208/fi-cfl-8109u/igt@kms_big_fb@y-tiled-max-hw-stride-64bpp-rotate-180-async-flip.html > ... > On APL it is less frequent, probably due to other bugs preventing run of > this test, last seen at: > https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_1190/fi-apl-guc/igt@kms_big_fb@y-tiled-max-hw-stride-32bpp-rotate-180-async-flip.html > Similar for SKL: > https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_1181/fi-skl-guc/igt@kms_big_fb@x-tiled-max-hw-stride-64bpp-rotate-180-async-flip.html > > I am not sure if I correctly read the docs but [1] says that 9th bit of > PLANE_CFG (Async Address Update Enable) is "not double buffered and the > changes will apply immediately" only for ICL, JSL, LKF1. It got broken in bdw and fixed again in icl. > So the change is not necessary in case of icl_plane_disable_arm. > > [1]: https://gfxspecs.intel.com/Predator/Home/Index/7656 > > > >> but if async update is enabled > >> PLANE_SURF register is updated asynchronously. Writing 0 to PLANE_SURF > >> when plane is still enabled can cause DMAR/PIPE errors. > >> On the other side PLANE_SURF is used to arm plane registers - we need to > >> write to it to trigger update on VBLANK, writting current value should > >> be safe - the buffer address is valid till vblank. > > I think you're effectively saying that somehow the async > > flip disable w/a is not kicking in sometimes. > > I was not aware of existence of this w/a and I am little lost in > figuring out how this w/a can prevent zeroing PLANE_SURF too early. When it works as designed it should: 1. turn off the async flip bit 2. wait for vblank so that gets latched 3. do the sync plane update/disable normally -- Ville Syrjälä Intel