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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8CD15CD1283 for ; Thu, 28 Mar 2024 16:47:56 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rpsuT-0001L2-Bd; Thu, 28 Mar 2024 12:47:25 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rpsuR-0001Kl-Rj; Thu, 28 Mar 2024 12:47:23 -0400 Received: from mx0b-0031df01.pphosted.com ([205.220.180.131]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rpsuP-0004hb-KQ; Thu, 28 Mar 2024 12:47:23 -0400 Received: from pps.filterd (m0279868.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.24/8.17.1.24) with ESMTP id 42SGW4rs029794; Thu, 28 Mar 2024 16:47:17 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h= date:from:to:cc:subject:message-id:references:mime-version :content-type:in-reply-to; s=qcppdkim1; bh=sVLtdL9BKfQ6sjDwg2AAh JivqRmilxR71j8l3i5hprg=; b=jHsP1VfGmhWlgl4ptUWhMq4nlIUTMRzb6kxnQ 5iuOnF8nWSBEJXnZWfkMT6bs8CKm/iYQ6pHdowJXsLQ3TcDQRrCDLotyr1GhsOW5 0Hu6SdY+e/PdoUclzms86j6r9STPRaBxUiyPzIdovGM2Q2nQElEay15S8W83WNvS aa7/1R7yISf6jdGw9mbmkn/5I3DfbBVPYLqS6VXZ4Y4ukBq6Y7yH0xFoMv9zcZ52 JwkqDuZIQauqFi73ejVWRabfSL5wFSrhb+UNa9CCMHpkkKtbhXj8FfdUASj1Jvw2 ELmqzq3KvSjkZsTTHiB9lag80nwiQ1rRkv+TGP2XbOxJjesBQ== Received: from nasanppmta01.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3x54r61kbr-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 28 Mar 2024 16:47:17 +0000 (GMT) Received: from nasanex01c.na.qualcomm.com (nasanex01c.na.qualcomm.com [10.45.79.139]) by NASANPPMTA01.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 42SGlFVJ009133 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 28 Mar 2024 16:47:15 GMT Received: from qc-i7.hemma.eciton.net (10.80.80.8) by nasanex01c.na.qualcomm.com (10.45.79.139) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.4; Thu, 28 Mar 2024 09:47:14 -0700 Date: Thu, 28 Mar 2024 16:47:10 +0000 From: Leif Lindholm To: Marcin Juszkiewicz CC: , , Peter Maydell , Radoslaw Biernacki Subject: Re: [PATCH v2 1/1] docs: sbsa: update specs, add dt note Message-ID: References: <20240328163851.1386176-1-marcin.juszkiewicz@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20240328163851.1386176-1-marcin.juszkiewicz@linaro.org> X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nasanex01c.na.qualcomm.com (10.45.79.139) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: _urmcyJupADUnV-Q5XkvAse6reqaMRCD X-Proofpoint-ORIG-GUID: _urmcyJupADUnV-Q5XkvAse6reqaMRCD X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1011,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2024-03-28_15,2024-03-28_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 adultscore=0 priorityscore=1501 clxscore=1011 lowpriorityscore=0 malwarescore=0 bulkscore=0 suspectscore=0 impostorscore=0 spamscore=0 mlxlogscore=687 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2403210001 definitions=main-2403280114 Received-SPF: pass client-ip=205.220.180.131; envelope-from=quic_llindhol@quicinc.com; helo=mx0b-0031df01.pphosted.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Thu, Mar 28, 2024 at 17:38:51 +0100, Marcin Juszkiewicz wrote: > Hardware of sbsa-ref board is nowadays defined by both BSA and SBSA > specifications. Then BBR defines firmware interface. > > Added note about DeviceTree data passed from QEMU to firmware. It is > very minimal and provides only data we use in firmware. > > Added NUMA information to list of things reported by DeviceTree. > > Signed-off-by: Marcin Juszkiewicz Reviewed-by: Leif Lindholm Thanks! / Leif > --- > docs/system/arm/sbsa.rst | 35 ++++++++++++++++++++++++++--------- > 1 file changed, 26 insertions(+), 9 deletions(-) > > diff --git a/docs/system/arm/sbsa.rst b/docs/system/arm/sbsa.rst > index bca61608ff..2bf22a1d0b 100644 > --- a/docs/system/arm/sbsa.rst > +++ b/docs/system/arm/sbsa.rst > @@ -1,12 +1,16 @@ > Arm Server Base System Architecture Reference board (``sbsa-ref``) > ================================================================== > > -While the ``virt`` board is a generic board platform that doesn't match > -any real hardware the ``sbsa-ref`` board intends to look like real > -hardware. The `Server Base System Architecture > -`_ defines a > -minimum base line of hardware support and importantly how the firmware > -reports that to any operating system. > +The ``sbsa-ref`` board intends to look like real hardware (while the ``virt`` > +board is a generic board platform that doesn't match any real hardware). > + > +The hardware part is defined by two specifications: > + > + - `Base System Architecture `__ (BSA) > + - `Server Base System Architecture `__ (SBSA) > + > +The `Arm Base Boot Requirements `__ (BBR) > +specification defines how the firmware reports that to any operating system. > > It is intended to be a machine for developing firmware and testing > standards compliance with operating systems. > @@ -35,16 +39,29 @@ includes both internal hardware and parts affected by the qemu command line > (i.e. CPUs and memory). As a result it must have a firmware specifically built > to expect a certain hardware layout (as you would in a real machine). > > +Note > +'''' > + > +QEMU provides the guest EL3 firmware with minimal information about hardware > +platform using minimalistic devicetree. This is not a Linux devicetree. It is > +not even a firmware devicetree. > + > +It is information passed from QEMU to describe the information a hardware > +platform would have other mechanisms to discover at runtime, that are affected > +by the QEMU command line. > + > +Ultimately this devicetree may be replaced by IPC calls to an emulated SCP. > + > DeviceTree information > '''''''''''''''''''''' > > -The devicetree provided by the board model to the firmware is not intended > -to be a complete compliant DT. It currently reports: > +The devicetree reports: > > - CPUs > - memory > - platform version > - GIC addresses > + - NUMA node id for CPUs and memory > > Platform version > '''''''''''''''' > @@ -70,4 +87,4 @@ Platform version changes: > GIC ITS information is present in devicetree. > > 0.3 > - The USB controller is an XHCI device, not EHCI > + The USB controller is an XHCI device, not EHCI. > -- > 2.44.0 >