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 082A7C433EF for ; Mon, 10 Jan 2022 17:42:57 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C6FDE112E19; Mon, 10 Jan 2022 17:42:55 +0000 (UTC) Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by gabe.freedesktop.org (Postfix) with ESMTPS id 87F44112D95 for ; Mon, 10 Jan 2022 17:42:53 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: alyssa) with ESMTPSA id 5A06E1F43EC1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1641836572; bh=i3BsaG3+9txF0hL7sD+dOncjvycYUSgtrjkjrBXPt/s=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=bt77E/Vk6J6qUmGkOV3EsgrRIru1UpllDQAb2NdpC/No5UlSYk/h203TOl2znG7rc 8KPwjcKjM+SFtwGXYD/d6hNTQi2bVSpB0cdXATvmeZaO+EK2CekF7tScoP3whHOmhA 5O7Cyq1vQI+511mtrLJn8muQBIu716aGh7daDogugb0ItaTMlDwmqYeyPD1g4veWaB Kt/cUmkwqGP57NCbzrKwvfvCkcYhgGQNS3P5I4c7jJeDX2HM23+aNM83EbKMUAWyzT hA2SR2AI9cOexlpEGHQrFD/LeJZKPBAG2NUKlSgQ11dRtvN5261g6/rdbWC9fZUBgD qfGa3SSq63pQQ== Date: Mon, 10 Jan 2022 12:42:44 -0500 From: Alyssa Rosenzweig To: Steven Price Subject: Re: [PATCH 2/2] drm/panfrost: adjusted job affinity for dual core group GPUs Message-ID: References: <20211223110616.2589851-1-asheplyakov@basealt.ru> <20211223110616.2589851-3-asheplyakov@basealt.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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: Tomeu Vizoso , "Vadim V . Vlasov" , dri-devel@lists.freedesktop.org, Alexey Sheplyakov , Alyssa Rosenzweig Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" > Whether it's worth the effort depends on whether anyone really cares > about getting the full performance out of this particular GPU. > > At this stage I think the main UABI change would be to add the opposite > flag to kbase, (e.g. "PANFROST_JD_DOESNT_NEED_COHERENCY_ON_GPU"[1]) to > opt-in to allowing the job to run across all cores. > > The second change would be to allow compute jobs to be run on the second > core group, so another flag: PANFROST_RUN_ON_SECOND_CORE_GROUP. > > But clearly there's little point adding such flags until someone steps > up to do the Mesa work. I worry about the maintainence burden (both Mesa and kernel) of adding UABI only used by a piece of hardware none of us own, and only useful "sometimes" for that hardware. Doubly so for the second core group support; currently Mesa doesn't advertise any compute support on anything older than Mali T760 ... to the best of my knowledge, nobody has missed that support either... To be clear I am in favour of merging the patches needed for GLES2 to work on all Malis, possibly at a performance cost on these dual-core systems. That's a far cry from the level of support the DDK gave these chips back in the day ... of course, the DDK doesn't support them at all anymore, so Panfrost wins there by default! ;)