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 172CF1171D; Fri, 26 Jul 2024 15:50:25 +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=1722009029; cv=none; b=lMkJlgYs+9FUAFbyf2tX6i4uQMA6n526SF6Spa1RfMjlirqhb4XPa6L5VfGKZiqLwq550MXMJq4PxDG1JKx8PyLOaqBQK7lRBF4dH7RSP274PbudRqpaGgef2H5M09m7rEVCypy6FYkTTE/mKpmnfRXW+3GIYkThA5N6kGRO/pM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722009029; c=relaxed/simple; bh=E2jNTVCDT1oeTIEW8YYWHSGp1rsFLEkH6YQwMzLLo1w=; h=Date:From:To:CC:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=n9u9a2Cg7IC8/3ehBX+gbuuHra47OolKfR2cpvCRLX/gs0rNLZvXy2/+QUlHGfNxjwFjt1bWdJ4chKCvz6YdcGVlEHf0RA0Xqv5Y10yiO4IU7FfJ6+OwdwAqe87lzuftI+SpTWFtK4LrA1eQLSKcVTyAae4mkvMWbQdOTJo/aYM= 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 [172.18.186.231]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4WVsbV5TCPz6K5Wr; Fri, 26 Jul 2024 23:48:06 +0800 (CST) Received: from lhrpeml500005.china.huawei.com (unknown [7.191.163.240]) by mail.maildlp.com (Postfix) with ESMTPS id 74FCA140AB8; Fri, 26 Jul 2024 23:50:23 +0800 (CST) Received: from localhost (10.203.174.77) 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, 26 Jul 2024 16:50:22 +0100 Date: Fri, 26 Jul 2024 16:50:21 +0100 From: Jonathan Cameron To: Jason Gunthorpe CC: Jonathan Corbet , Itay Avraham , Jakub Kicinski , Leon Romanovsky , , , , Paolo Abeni , Saeed Mahameed , Tariq Toukan , Andy Gospodarek , Aron Silverton , Dan Williams , David Ahern , Christoph Hellwig , Jiri Pirko , Leonid Bloch , "Leon Romanovsky" , , Subject: Re: [PATCH v2 6/8] fwctl: Add documentation Message-ID: <20240726165021.000002d6@Huawei.com> In-Reply-To: <6-v2-940e479ceba9+3821-fwctl_jgg@nvidia.com> References: <0-v2-940e479ceba9+3821-fwctl_jgg@nvidia.com> <6-v2-940e479ceba9+3821-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-doc@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: lhrpeml500003.china.huawei.com (7.191.162.67) To lhrpeml500005.china.huawei.com (7.191.163.240) > diff --git a/Documentation/userspace-api/fwctl.rst b/Documentation/userspace-api/fwctl.rst > new file mode 100644 > index 00000000000000..ece2db2530502f > --- /dev/null > +++ b/Documentation/userspace-api/fwctl.rst > @@ -0,0 +1,269 @@ > +Overview > +======== > + > +Modern devices contain extensive amounts of FW, and in many cases, are largely FW and, in many cases, are > +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 document lays out where this sits well. Jonathan