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 BCFCFEB64D9 for ; Tue, 27 Jun 2023 15:42:07 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 69DF010E30E; Tue, 27 Jun 2023 15:42:06 +0000 (UTC) Received: from 189.cn (ptr.189.cn [183.61.185.101]) by gabe.freedesktop.org (Postfix) with ESMTP id 83E7410E318 for ; Tue, 27 Jun 2023 15:42:02 +0000 (UTC) HMM_SOURCE_IP: 10.64.8.41:47796.1468361982 HMM_ATTACHE_NUM: 0000 HMM_SOURCE_TYPE: SMTP Received: from clientip-114.242.206.180 (unknown [10.64.8.41]) by 189.cn (HERMES) with SMTP id C284D1001BD; Tue, 27 Jun 2023 23:41:57 +0800 (CST) Received: from ([114.242.206.180]) by gateway-151646-dep-75648544bd-xwndj with ESMTP id 092d237c49d1407192172e5a3eeb9f6f for suijingfeng@loongson.cn; Tue, 27 Jun 2023 23:41:58 CST X-Transaction-ID: 092d237c49d1407192172e5a3eeb9f6f X-Real-From: 15330273260@189.cn X-Receive-IP: 114.242.206.180 X-MEDUSA-Status: 0 Message-ID: Date: Tue, 27 Jun 2023 23:41:55 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Subject: Re: [PATCH v15 1/2] drm: Add kms driver for loongson display controller Content-Language: en-US To: Sui Jingfeng , Huacai Chen References: <20230615143613.1236245-1-15330273260@189.cn> <20230615143613.1236245-2-15330273260@189.cn> <7e60a8a7-e7c9-285c-a997-7404c2b8f802@loongson.cn> From: Sui Jingfeng <15330273260@189.cn> In-Reply-To: <7e60a8a7-e7c9-285c-a997-7404c2b8f802@loongson.cn> Content-Type: text/plain; charset=UTF-8; format=flowed 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: Nathan Chancellor , Thomas Zimmermann , inux-kernel@vger.kernel.org, Emil Velikov , Maxime Ripard , Christian Koenig , loongson-kernel@lists.loongnix.cn, Liu Peibao , dri-devel@lists.freedesktop.org, Geert Uytterhoeven , Sumit Semwal , linux-media@vger.kernel.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On 2023/6/27 23:27, Sui Jingfeng wrote: > Hi, > > On 2023/6/19 18:19, Huacai Chen wrote: >>> Single patch is more easy to manage. >>> >>> The first patch of this driver should comes a whole. >> Benchmarks and debugfs are not the very basic parts. > > In the V2, > > Thomas told me that if we implement our own TTM-based memory manager, > > we will also have the possibility of implementing a faster console. > > > Back to that time I do not even know the bandwidth of our hardware. > > 1) The bandwidth of copying buffer from the system RAM to system RAM; > > 2) The bandwidth of copying buffer from the system RAM to dedicated VRAM; > > 3) The bandwidth of copying buffer from the dedicated VRAM to system RAM; > > > We can make the right decision only when we know the various bandwidth > listed as above. > > How to implement it. > I means that the benchmarks can actually improve your cognition toward the hardware. Where is the bottleneck of the performance. It also can be a kind of self test, to verify if various parts works as expected.