From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lelvem-ot01.ext.ti.com (lelvem-ot01.ext.ti.com [198.47.23.234]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4BCE820E03F; Wed, 17 Sep 2025 11:46:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.47.23.234 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758109575; cv=none; b=N+wYAHEw1p1g1+odNFHOmQK4VgH+BP34kSA4tariNwpoI50nZRfCt+ef/2dQwKe3/CafcRS5zjCd4BMsqo/D1nNBAH9H91ixxSkW7VEodvcnOpI+Yxk3iAbcbZy+ckjc41O3PRHq+bxXunef8bHQ5bxERjU/JmDWtMj4ckBU1D8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758109575; c=relaxed/simple; bh=GE1ZvajMjR1jpdcyQ23SFnVuz3QmYfCASBO13hwms0Q=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=VEFe8TkLGPiV3YPVwaYYI9L0gEUYM336U/YFilgfBMO3NN8NdlWsl2pOouTfIVpuBrDMazOvE1V7lZG061tvdeeQqieDWFVYlndh9py9ZUAtQEoatzPNR7eC3IAuxGglNIbPtE+pgqtNPjYukBm9tz5lsrvgR1+wL1J71FQzANU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ti.com; spf=pass smtp.mailfrom=ti.com; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b=c31U7ebF; arc=none smtp.client-ip=198.47.23.234 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ti.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ti.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="c31U7ebF" Received: from fllvem-sh04.itg.ti.com ([10.64.41.54]) by lelvem-ot01.ext.ti.com (8.15.2/8.15.2) with ESMTP id 58HBj7G91597639; Wed, 17 Sep 2025 06:45:07 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1758109507; bh=CESIdT/b5vC34F/eerVXaRdloEbeJeSQadVRXpn30xo=; h=Date:Subject:To:CC:References:From:In-Reply-To; b=c31U7ebFlqU6kZuPjeR3YrLRk3pu22idBxlSh8Qez5VPn+A9Pd896Vfs9dUFchjaq WQwPgC5USgoJu/BmU6RwfRFBd+IXgVYn/3y/Td1AAmKwptbKrDi3dYpM36blp2qNPj QyUxKkARwRsEFJiJufjePXpCFZiDDPIr7n+JX6Ro= Received: from DLEE100.ent.ti.com (dlee100.ent.ti.com [157.170.170.30]) by fllvem-sh04.itg.ti.com (8.18.1/8.18.1) with ESMTPS id 58HBj6CM2312628 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA256 bits=128 verify=FAIL); Wed, 17 Sep 2025 06:45:06 -0500 Received: from DLEE213.ent.ti.com (157.170.170.116) by DLEE100.ent.ti.com (157.170.170.30) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.55; Wed, 17 Sep 2025 06:45:06 -0500 Received: from lelvem-mr06.itg.ti.com (10.180.75.8) by DLEE213.ent.ti.com (157.170.170.116) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.20 via Frontend Transport; Wed, 17 Sep 2025 06:45:06 -0500 Received: from [172.24.231.152] (danish-tpc.dhcp.ti.com [172.24.231.152]) by lelvem-mr06.itg.ti.com (8.18.1/8.18.1) with ESMTP id 58HBivYL2975345; Wed, 17 Sep 2025 06:44:58 -0500 Message-ID: <7cd06f8f-bd74-429d-bf2c-71858178950a@ti.com> Date: Wed, 17 Sep 2025 17:14:57 +0530 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net-next v4 0/7] Add RPMSG Ethernet Driver To: Andrew Davis , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Jonathan Corbet , Nishanth Menon , Vignesh Raghavendra , Tero Kristo , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Andrew Lunn , Mengyuan Lou , Lei Wei , Xin Guo , Michael Ellerman , Fan Gong , Lorenzo Bianconi , Parthiban Veerasooran , Lukas Bulwahn , Geert Uytterhoeven CC: , , , , References: <20250911113612.2598643-1-danishanwar@ti.com> <8a20160e-1528-4d0e-9347-0561fc3426b4@ti.com> Content-Language: en-US From: MD Danish Anwar In-Reply-To: <8a20160e-1528-4d0e-9347-0561fc3426b4@ti.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-C2ProcessedOrg: 333ef613-75bf-4e12-a4b1-8e3623f5dcea Hi Andrew, On 11/09/25 9:34 pm, Andrew Davis wrote: > On 9/11/25 6:36 AM, MD Danish Anwar wrote: >> This patch series introduces the RPMSG Ethernet driver, which provides a >> virtual Ethernet interface for communication between a host processor and >> a remote processor using the RPMSG framework. The driver enables >> Ethernet-like packet transmission and reception over shared memory, >> facilitating inter-core communication in systems with heterogeneous >> processors. >> > > This is neat and all but I have to ask: why? What does this provide > that couldn't be done with normal RPMSG messages? Or from a userspace > TAP/TUN driver on top of RPMSG? > This is different from RPMSG because here I am not using RPMSG to do the actual TX / RX. RPMSG is only used to share information (tx / rx offsets, buffer size, etc) between driver and firmware. The TX / RX happens in the shared memory. This implementation uses a shared memory circular buffer with head/tail pointers for efficient data passing without copies between cores. > This also feels like some odd layering, as RPMSG sits on virtio, and > we have virtio-net, couldn't we have a firmware just expose that (or > would the firmware be vhost-net..)? > PMSG sits on virtio, and we do have virtio-net but I am not trying to do ethernet communication over RPMSG. RPMSG is only used to exchange information between cores regarding the shared memory where the actual ethernet communication happens. > Andrew > -- Thanks and Regards, Danish