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=-4.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,HK_RANDOM_FROM,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 2ED36C433ED for ; Fri, 14 May 2021 11:12:05 +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 D9EBB613D6 for ; Fri, 14 May 2021 11:12:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D9EBB613D6 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 368E16EE45; Fri, 14 May 2021 11:12:04 +0000 (UTC) Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8659D6EE52; Fri, 14 May 2021 11:12:02 +0000 (UTC) IronPort-SDR: tiUiHcU4gw0/OyMH3+4uxXfcxFhlRSVNSJUEfV3f96c9MwUDi3WUAtoM779qZeDJ5S6/8AjRkN nCDm3j3osw2g== X-IronPort-AV: E=McAfee;i="6200,9189,9983"; a="179757135" X-IronPort-AV: E=Sophos;i="5.82,299,1613462400"; d="scan'208";a="179757135" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 May 2021 04:12:01 -0700 IronPort-SDR: tGeCVerlNCsVT6HWquh+rnOvu/wufU/Tt/pquuyf99FMeLweFxH81WOxNRAmUuOjyzvE8VvIz+ S54St88rfsoQ== X-IronPort-AV: E=Sophos;i="5.82,299,1613462400"; d="scan'208";a="393589143" Received: from ankitsi2-mobl.ger.corp.intel.com (HELO [10.213.242.91]) ([10.213.242.91]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 May 2021 04:11:59 -0700 Subject: Re: [Intel-gfx] [RFC PATCH 00/97] Basic GuC submission support in the i915 To: Matthew Brost , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org References: <20210506191451.77768-1-matthew.brost@intel.com> From: Tvrtko Ursulin Organization: Intel Corporation UK Plc Message-ID: Date: Fri, 14 May 2021 12:11:56 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: <20210506191451.77768-1-matthew.brost@intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit 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: jason.ekstrand@intel.com, daniel.vetter@intel.com Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On 06/05/2021 20:13, Matthew Brost wrote: > Basic GuC submission support. This is the first bullet point in the > upstreaming plan covered in the following RFC [1]. > > At a very high level the GuC is a piece of firmware which sits between > the i915 and the GPU. It offloads some of the scheduling of contexts > from the i915 and programs the GPU to submit contexts. The i915 > communicates with the GuC and the GuC communicates with the GPU. > > GuC submission will be disabled by default on all current upstream > platforms behind a module parameter - enable_guc. A value of 3 will > enable submission and HuC loading via the GuC. GuC submission should > work on all gen11+ platforms assuming the GuC firmware is present. Some thoughts mostly relating to future platforms where GuC will be the only option, and to some extent platforms where it will be possible to turn it on for one reason or another. Debuggability - in the context of having an upstream way/tool for capturing and viewing GuC logs usable for attaching to bug reports. Currently i915 logs, can provide traces via tracepoints and trace printk, and GPU error capture state, which provides often sufficient trail of evidence to debug issues. We need to make sure GuC does is not a black box in this respect. By this I mean it does not hide a large portion of the execution flows from upstream observability. This could mean a tool in IGT to access/capture GuC logs and update bug filing instructions. Leading from here is probably the need for the GuC firmware team to cross the internal-upstream boundary and deal with such bug reports on upstream trackers. Upstream GuC is unlikely to work if we don't have such plan and commitment. Also leading from here is the need for GPU error capture to be on par from day one which is I believe still not there in the firmware. Another, although unrelated, missing feature on my wish list is firmware support for wiring up accurate engine busyness stats to i915 PMU. I believe this is also being worked on but I don't know when is the expected delivery. If we are tracking a TODO list of items somewhere I think these ones should be definitely considered. Regards, Tvrtko 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=-4.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,HK_RANDOM_FROM,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 CC6F8C433ED for ; Fri, 14 May 2021 11:12:07 +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 8801E613D6 for ; Fri, 14 May 2021 11:12:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8801E613D6 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=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BBAF96E1B7; Fri, 14 May 2021 11:12:04 +0000 (UTC) Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8659D6EE52; Fri, 14 May 2021 11:12:02 +0000 (UTC) IronPort-SDR: tiUiHcU4gw0/OyMH3+4uxXfcxFhlRSVNSJUEfV3f96c9MwUDi3WUAtoM779qZeDJ5S6/8AjRkN nCDm3j3osw2g== X-IronPort-AV: E=McAfee;i="6200,9189,9983"; a="179757135" X-IronPort-AV: E=Sophos;i="5.82,299,1613462400"; d="scan'208";a="179757135" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 May 2021 04:12:01 -0700 IronPort-SDR: tGeCVerlNCsVT6HWquh+rnOvu/wufU/Tt/pquuyf99FMeLweFxH81WOxNRAmUuOjyzvE8VvIz+ S54St88rfsoQ== X-IronPort-AV: E=Sophos;i="5.82,299,1613462400"; d="scan'208";a="393589143" Received: from ankitsi2-mobl.ger.corp.intel.com (HELO [10.213.242.91]) ([10.213.242.91]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 May 2021 04:11:59 -0700 To: Matthew Brost , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org References: <20210506191451.77768-1-matthew.brost@intel.com> From: Tvrtko Ursulin Organization: Intel Corporation UK Plc Message-ID: Date: Fri, 14 May 2021 12:11:56 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: <20210506191451.77768-1-matthew.brost@intel.com> Content-Language: en-US Subject: Re: [Intel-gfx] [RFC PATCH 00/97] Basic GuC submission support in the i915 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: jason.ekstrand@intel.com, daniel.vetter@intel.com Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On 06/05/2021 20:13, Matthew Brost wrote: > Basic GuC submission support. This is the first bullet point in the > upstreaming plan covered in the following RFC [1]. > > At a very high level the GuC is a piece of firmware which sits between > the i915 and the GPU. It offloads some of the scheduling of contexts > from the i915 and programs the GPU to submit contexts. The i915 > communicates with the GuC and the GuC communicates with the GPU. > > GuC submission will be disabled by default on all current upstream > platforms behind a module parameter - enable_guc. A value of 3 will > enable submission and HuC loading via the GuC. GuC submission should > work on all gen11+ platforms assuming the GuC firmware is present. Some thoughts mostly relating to future platforms where GuC will be the only option, and to some extent platforms where it will be possible to turn it on for one reason or another. Debuggability - in the context of having an upstream way/tool for capturing and viewing GuC logs usable for attaching to bug reports. Currently i915 logs, can provide traces via tracepoints and trace printk, and GPU error capture state, which provides often sufficient trail of evidence to debug issues. We need to make sure GuC does is not a black box in this respect. By this I mean it does not hide a large portion of the execution flows from upstream observability. This could mean a tool in IGT to access/capture GuC logs and update bug filing instructions. Leading from here is probably the need for the GuC firmware team to cross the internal-upstream boundary and deal with such bug reports on upstream trackers. Upstream GuC is unlikely to work if we don't have such plan and commitment. Also leading from here is the need for GPU error capture to be on par from day one which is I believe still not there in the firmware. Another, although unrelated, missing feature on my wish list is firmware support for wiring up accurate engine busyness stats to i915 PMU. I believe this is also being worked on but I don't know when is the expected delivery. If we are tracking a TODO list of items somewhere I think these ones should be definitely considered. Regards, Tvrtko _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx