From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) (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 00DFC18453C; Fri, 23 Aug 2024 14:35:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.176.79.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724423723; cv=none; b=g0tzIhtcs57bPojtoTbDNQR2gx/e6dQdZXTw3+IoS3kMZwFECoAUoC8Tana4/Wj3CNz8DxVH8QC6ihjPQ9t81yw7tc1vHC273+h6ywA/hg1REJvP2106fYVLQ0ApZGElJpIameqSFJ0B09frtvWZXlHBABeVsvWl7OWHXyvD1tU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724423723; c=relaxed/simple; bh=pBL3ap7bMgMjYKLDZVHWrfgYzXV6+h/J6k6ee6lAWx4=; h=Date:From:To:CC:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=nFDW+3KQ8FuzdgryyNnJyR4dxLsJmJ/KXqNZcc2ezW7ZImt+o75LnUXuRbi6Ms7dUTu2tmSGOR0nrEJ90yQjAQRlBKAtPp4kx0MASxFrV0pmsQ2phe4DaDcQDyYUh2Ex25ws2KFPbZioIiw0h3sWFOE8dHOUqcX95/kIktJta+g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=Huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=185.176.79.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=Huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.18.186.216]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4Wr2Zy3Bxdz6K93W; Fri, 23 Aug 2024 22:32:10 +0800 (CST) Received: from lhrpeml500005.china.huawei.com (unknown [7.191.163.240]) by mail.maildlp.com (Postfix) with ESMTPS id 32127140447; Fri, 23 Aug 2024 22:35:15 +0800 (CST) Received: from localhost (10.203.177.66) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Fri, 23 Aug 2024 15:35:14 +0100 Date: Fri, 23 Aug 2024 15:35:13 +0100 From: Jonathan Cameron To: Jason Gunthorpe CC: Andy Gospodarek , Aron Silverton , Dan Williams , Daniel Vetter , Dave Jiang , David Ahern , "Greg Kroah-Hartman" , Christoph Hellwig , Itay Avraham , Jiri Pirko , Jakub Kicinski , Leonid Bloch , Leon Romanovsky , , , Saeed Mahameed Subject: Re: [PATCH v3 06/10] fwctl: Add documentation Message-ID: <20240823153513.00000499@Huawei.com> In-Reply-To: <6-v3-960f17f90f17+516-fwctl_jgg@nvidia.com> References: <0-v3-960f17f90f17+516-fwctl_jgg@nvidia.com> <6-v3-960f17f90f17+516-fwctl_jgg@nvidia.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.1.0 (GTK 3.24.33; x86_64-w64-mingw32) Precedence: bulk X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: lhrpeml500005.china.huawei.com (7.191.163.240) To lhrpeml500005.china.huawei.com (7.191.163.240) On Wed, 21 Aug 2024 15:10:58 -0300 Jason Gunthorpe wrote: > Document the purpose and rules for the fwctl subsystem. > > Link in kdocs to the doc tree. > > Nacked-by: Jakub Kicinski > Link: https://lore.kernel.org/r/20240603114250.5325279c@kernel.org > Acked-by: Daniel Vetter > https://lore.kernel.org/r/ZrHY2Bds7oF7KRGz@phenom.ffwll.local > Signed-off-by: Jason Gunthorpe Just one trivial plural / singular comment. Reviewed-by: Jonathan Cameron > --- > Documentation/userspace-api/fwctl.rst | 285 ++++++++++++++++++++++++++ > Documentation/userspace-api/index.rst | 1 + > 2 files changed, 286 insertions(+) > create mode 100644 Documentation/userspace-api/fwctl.rst > > diff --git a/Documentation/userspace-api/fwctl.rst b/Documentation/userspace-api/fwctl.rst > new file mode 100644 > index 00000000000000..8f3da30ee7c91b > --- /dev/null > +++ b/Documentation/userspace-api/fwctl.rst > @@ -0,0 +1,285 @@ > +.. SPDX-License-Identifier: GPL-2.0 > + > +=============== > +fwctl subsystem > +=============== > + > +:Author: Jason Gunthorpe > + > +Overview > +======== > + > +Modern devices contain extensive amounts of FW, and in many cases, are largely > +software-defined pieces of hardware. The evolution of this approach is largely a > +reaction to Moore's Law where a chip tape out is now highly expensive, and the > +chip design is extremely large. Replacing fixed HW logic with a flexible and > +tightly coupled FW/HW combination is an effective risk mitigation against chip > +respin. Problems in the HW design can be counteracted in device FW. This is > +especially true for devices which present a stable and backwards compatible > +interface to the operating system driver (such as NVMe). > + > +The FW layer in devices has grown to incredible sizes and devices frequently incredible size (tricky to get the plurals right in this sentence, but currently its a mixture) > +integrate clusters of fast processors to run it. For example, mlx5 devices have > +over 30MB of FW code, and big configurations operate with over 1GB of FW managed > +runtime state. ...