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 X-Spam-Level: X-Spam-Status: No, score=-8.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 001CEC67802 for ; Thu, 11 Oct 2018 16:27:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BCABE20658 for ; Thu, 11 Oct 2018 16:27:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="ambQx7lK" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BCABE20658 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729958AbeJKXzr (ORCPT ); Thu, 11 Oct 2018 19:55:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:34708 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729906AbeJKXzr (ORCPT ); Thu, 11 Oct 2018 19:55:47 -0400 Received: from localhost (unknown [204.56.7.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6FCB820658; Thu, 11 Oct 2018 16:27:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1539275268; bh=bw9IHwLHTNF/IzB7MYNkhTRBQgrJLHEsOWFRdFiDp8E=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ambQx7lK0tBhOC4v/k19lqmU8vOLHwmuOKQYwK9OrYW9Pc2Nz88CRJZ8TBykh1QtJ gg2cD/VzwkKWuu//DV2sWMZAxx86l9bWPTtJZtyzfOVk6p5hXwRAQYBH5To5fe9kIG PLYIkNp2ubrMKSl7ewlODg+jIPVIqeD/9YpTSg38= Date: Thu, 11 Oct 2018 11:27:47 -0500 From: Bjorn Helgaas To: Wesley Sheng Cc: bhelgaas@google.com, corbet@lwn.net, logang@deltatee.com, kurt.schwemmer@microsemi.com, linux-ntb@googlegroups.com, linux-pci@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Wesley Yung , Kelvin Cao , Jon Mason Subject: Re: [PATCH v3] NTB: switchtec_ntb: Update switchtec documentation with pre-requisites for NTB Message-ID: <20181011162747.GP5906@bhelgaas-glaptop.roam.corp.google.com> References: <1539182575-26851-1-git-send-email-wesley.sheng@microchip.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1539182575-26851-1-git-send-email-wesley.sheng@microchip.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [+cc Jon Mason] On Wed, Oct 10, 2018 at 10:42:55PM +0800, Wesley Sheng wrote: > From: Wesley Yung > > The ntb_hw_switchtec driver has requirements on kernel configuration > so we add these notes to the documentation and also clean up a few > other sentences in the documentation. > > Signed-off-by: Wesley Yung > Signed-off-by: Kelvin Cao > Signed-off-by: Wesley Sheng I'm not sure who should really own this file: $ ./scripts/get_maintainer.pl -f Documentation/switchtec.txt Kurt Schwemmer (maintainer:PCI DRIVER FOR MICROSEMI SWITCHTEC) Logan Gunthorpe (maintainer:PCI DRIVER FOR MICROSEMI SWITCHTEC) Jonathan Corbet (maintainer:DOCUMENTATION) linux-pci@vger.kernel.org (open list:PCI DRIVER FOR MICROSEMI SWITCHTEC) linux-doc@vger.kernel.org (open list:DOCUMENTATION) linux-kernel@vger.kernel.org (open list) and Jon (NTB driver core maintainer) has applied recent updates to it. But in the interest of forward progress, I applied this patch with Logan's ack to pci/misc for v4.20. > --- > Documentation/switchtec.txt | 30 ++++++++++++++++++++---------- > 1 file changed, 20 insertions(+), 10 deletions(-) > > diff --git a/Documentation/switchtec.txt b/Documentation/switchtec.txt > index f788264..d6f04dcc 100644 > --- a/Documentation/switchtec.txt > +++ b/Documentation/switchtec.txt > @@ -23,7 +23,7 @@ The primary means of communicating with the Switchtec management firmware is > through the Memory-mapped Remote Procedure Call (MRPC) interface. > Commands are submitted to the interface with a 4-byte command > identifier and up to 1KB of command specific data. The firmware will > -respond with a 4 bytes return code and up to 1KB of command specific > +respond with a 4-byte return code and up to 1KB of command specific > data. The interface only processes a single command at a time. > > > @@ -36,8 +36,8 @@ device: /dev/switchtec#, one for each management endpoint in the system. > The char device has the following semantics: > > * A write must consist of at least 4 bytes and no more than 1028 bytes. > - The first four bytes will be interpreted as the command to run and > - the remainder will be used as the input data. A write will send the > + The first 4 bytes will be interpreted as the Command ID and the > + remainder will be used as the input data. A write will send the > command to the firmware to begin processing. > > * Each write must be followed by exactly one read. Any double write will > @@ -45,9 +45,9 @@ The char device has the following semantics: > produce an error. > > * A read will block until the firmware completes the command and return > - the four bytes of status plus up to 1024 bytes of output data. (The > - length will be specified by the size parameter of the read call -- > - reading less than 4 bytes will produce an error. > + the 4-byte Command Return Value plus up to 1024 bytes of output > + data. (The length will be specified by the size parameter of the read > + call -- reading less than 4 bytes will produce an error.) > > * The poll call will also be supported for userspace applications that > need to do other things while waiting for the command to complete. > @@ -83,10 +83,20 @@ The following IOCTLs are also supported by the device: > Non-Transparent Bridge (NTB) Driver > =================================== > > -An NTB driver is provided for the switchtec hardware in switchtec_ntb. > -Currently, it only supports switches configured with exactly 2 > -partitions. It also requires the following configuration settings: > +An NTB hardware driver is provided for the Switchtec hardware in > +ntb_hw_switchtec. Currently, it only supports switches configured with > +exactly 2 NT partitions and zero or more non-NT partitions. It also requires > +the following configuration settings: > > -* Both partitions must be able to access each other's GAS spaces. > +* Both NT partitions must be able to access each other's GAS spaces. > Thus, the bits in the GAS Access Vector under Management Settings > must be set to support this. > +* Kernel configuration MUST include support for NTB (CONFIG_NTB needs > + to be set) > + > +NT EP BAR 2 will be dynamically configured as a Direct Window, and > +the configuration file does not need to configure it explicitly. > + > +Please refer to Documentation/ntb.txt in Linux source tree for an overall > +understanding of the Linux NTB stack. ntb_hw_switchtec works as an NTB > +Hardware Driver in this stack. > -- > 2.7.4 >