From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id A6BB643D4E; Tue, 26 Mar 2024 02:42:10 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 3722E402C0; Tue, 26 Mar 2024 02:42:10 +0100 (CET) Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by mails.dpdk.org (Postfix) with ESMTP id B27DD402B5 for ; Tue, 26 Mar 2024 02:42:08 +0100 (CET) Received: from mail.maildlp.com (unknown [172.19.88.105]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4V3XXb56STzwQ6d; Tue, 26 Mar 2024 09:39:27 +0800 (CST) Received: from kwepemm600004.china.huawei.com (unknown [7.193.23.242]) by mail.maildlp.com (Postfix) with ESMTPS id 75836140257; Tue, 26 Mar 2024 09:42:06 +0800 (CST) Received: from [10.67.121.59] (10.67.121.59) by kwepemm600004.china.huawei.com (7.193.23.242) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.35; Tue, 26 Mar 2024 09:42:05 +0800 Message-ID: <68ee0a54-c0b4-293c-67ee-efed8964c33b@huawei.com> Date: Tue, 26 Mar 2024 09:42:05 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.2.0 Subject: Re: [PATCH v2 1/6] ethdev: support setting lanes To: Thomas Monjalon , huangdengdui , Damodharam Ammepalli CC: , , Damodharam Ammepalli , , , , , , , , , , References: <20240312075238.3319480-4-huangdengdui@huawei.com> <4413054.MSiuQNM8U4@thomas> <90a508af-7b6d-4026-b4e9-ec35c0df9b97@huawei.com> <3325989.AxlXzFCzgd@thomas> From: "lihuisong (C)" In-Reply-To: <3325989.AxlXzFCzgd@thomas> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.67.121.59] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemm600004.china.huawei.com (7.193.23.242) X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org 在 2024/3/25 17:30, Thomas Monjalon 写道: > 25/03/2024 07:24, huangdengdui: >> On 2024/3/22 21:58, Thomas Monjalon wrote: >>> 22/03/2024 08:09, Dengdui Huang: >>>> -#define RTE_ETH_LINK_SPEED_10G RTE_BIT32(8) /**< 10 Gbps */ >>>> -#define RTE_ETH_LINK_SPEED_20G RTE_BIT32(9) /**< 20 Gbps */ >>>> -#define RTE_ETH_LINK_SPEED_25G RTE_BIT32(10) /**< 25 Gbps */ >>>> -#define RTE_ETH_LINK_SPEED_40G RTE_BIT32(11) /**< 40 Gbps */ >>>> -#define RTE_ETH_LINK_SPEED_50G RTE_BIT32(12) /**< 50 Gbps */ >>>> -#define RTE_ETH_LINK_SPEED_56G RTE_BIT32(13) /**< 56 Gbps */ >>>> -#define RTE_ETH_LINK_SPEED_100G RTE_BIT32(14) /**< 100 Gbps */ >>>> -#define RTE_ETH_LINK_SPEED_200G RTE_BIT32(15) /**< 200 Gbps */ >>>> -#define RTE_ETH_LINK_SPEED_400G RTE_BIT32(16) /**< 400 Gbps */ >>>> +#define RTE_ETH_LINK_SPEED_10G RTE_BIT32(8) /**< 10 Gbps */ >>>> +#define RTE_ETH_LINK_SPEED_20G RTE_BIT32(9) /**< 20 Gbps 2lanes */ >>>> +#define RTE_ETH_LINK_SPEED_25G RTE_BIT32(10) /**< 25 Gbps */ >>>> +#define RTE_ETH_LINK_SPEED_40G RTE_BIT32(11) /**< 40 Gbps 4lanes */ >>>> +#define RTE_ETH_LINK_SPEED_50G RTE_BIT32(12) /**< 50 Gbps */ >>>> +#define RTE_ETH_LINK_SPEED_56G RTE_BIT32(13) /**< 56 Gbps 4lanes */ >>>> +#define RTE_ETH_LINK_SPEED_100G RTE_BIT32(14) /**< 100 Gbps */ >>>> +#define RTE_ETH_LINK_SPEED_200G RTE_BIT32(15) /**< 200 Gbps 4lanes */ >>>> +#define RTE_ETH_LINK_SPEED_400G RTE_BIT32(16) /**< 400 Gbps 4lanes */ >>>> +#define RTE_ETH_LINK_SPEED_10G_4LANES RTE_BIT32(17) /**< 10 Gbps 4lanes */ >>>> +#define RTE_ETH_LINK_SPEED_50G_2LANES RTE_BIT32(18) /**< 50 Gbps 2 lanes */ >>>> +#define RTE_ETH_LINK_SPEED_100G_2LANES RTE_BIT32(19) /**< 100 Gbps 2 lanes */ >>>> +#define RTE_ETH_LINK_SPEED_100G_4LANES RTE_BIT32(20) /**< 100 Gbps 4lanes */ >>>> +#define RTE_ETH_LINK_SPEED_200G_2LANES RTE_BIT32(21) /**< 200 Gbps 2lanes */ >>>> +#define RTE_ETH_LINK_SPEED_400G_8LANES RTE_BIT32(22) /**< 400 Gbps 8lanes */ >>> I don't think it is a good idea to make this more complex. >>> It brings nothing as far as I can see, compared to having speed and lanes separated. >>> Can we have lanes information a separate value? no need for bitmask. >>> >> Hi,Thomas, Ajit, roretzla, damodharam >> >> I also considered the option at the beginning of the design. >> But this option is not used due to the following reasons: >> 1. For the user, ethtool couples speed and lanes. >> The result of querying the NIC capability is as follows: >> Supported link modes: >> 100000baseSR4/Full >> 100000baseSR2/Full >> The NIC capability is configured as follows: >> ethtool -s eth1 speed 100000 lanes 4 autoneg off >> ethtool -s eth1 speed 100000 lanes 2 autoneg off >> >> Therefore, users are more accustomed to the coupling of speed and lanes. >> >> 2. For the PHY, When the physical layer capability is configured through the MDIO, >> the speed and lanes are also coupled. >> For example: >> Table 45–7—PMA/PMD control 2 register bit definitions[1] >> PMA/PMD type selection >> 1 0 0 1 0 1 0 = 100GBASE-SR2 PMA/PMD >> 0 1 0 1 1 1 1 = 100GBASE-SR4 PMA/PMD >> >> Therefore, coupling speeds and lanes is easier to understand. >> And it is easier for the driver to report the support lanes. >> >> In addition, the code implementation is compatible with the old version. >> When the driver does not support the lanes setting, the code does not need to be modified. >> >> So I think the speed and lanes coupling is better. > I don't think so. > You are mixing hardware implementation, user tool, and API. > Having a separate and simple API is cleaner and not more difficult to handle > in some get/set style functions. Having a separate and simple API is cleaner. It's good. But supported lane capabilities have a lot to do with the specified speed. This is determined by releated specification. If we add a separate API for speed lanes, it probably is hard to check the validity of the configuration for speed and lanes. And the setting lane API sepparated from speed is not good for uniforming all PMD's behavior in ethdev layer. The patch[1] is an example for this separate API. I think it is not very good. It cannot tell user and PMD the follow points: 1) user don't know what lanes should or can be set for a specified speed on one NIC. 2) how should PMD do for a supported lanes in their HW? Anyway, if we add setting speed lanes feature, we must report and set speed and lanes capabilities for user well. otherwise, user will be more confused. [1] https://patchwork.dpdk.org/project/dpdk/list/?series=31606 BR, /Huisong > > > > .