From patchwork Fri May 6 05:51:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Alexey Kardashevskiy X-Patchwork-Id: 1627403 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) 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 bilbo.ozlabs.org (Postfix) with ESMTPS id 4KvfqD0Wvpz9sBF for ; Fri, 6 May 2022 15:52:38 +1000 (AEST) Received: from localhost ([::1]:60280 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nmqtH-0004xP-4o for incoming@patchwork.ozlabs.org; Fri, 06 May 2022 01:52:35 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60098) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nmqsK-0004wJ-Go; Fri, 06 May 2022 01:51:36 -0400 Received: from ozlabs.ru ([107.174.27.60]:47968) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nmqsI-0004Ax-AM; Fri, 06 May 2022 01:51:35 -0400 Received: from fstn1-p1.ozlabs.ibm.com. (localhost [IPv6:::1]) by ozlabs.ru (Postfix) with ESMTP id 2269480152; Fri, 6 May 2022 01:51:27 -0400 (EDT) From: Alexey Kardashevskiy To: qemu-ppc@nongnu.org Cc: Alexey Kardashevskiy , qemu-devel@nongnu.org, Joel Stanley Subject: [RFC PATCH qemu] spapr/docs: Add a few words about x-vof Date: Fri, 6 May 2022 15:51:24 +1000 Message-Id: <20220506055124.3822112-1-aik@ozlabs.ru> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Received-SPF: pass client-ip=107.174.27.60; envelope-from=aik@ozlabs.ru; helo=ozlabs.ru X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" The alternative small firmware needs a few words of what it can and absolutely cannot do; this adds those words. Signed-off-by: Alexey Kardashevskiy --- docs/system/ppc/pseries.rst | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/docs/system/ppc/pseries.rst b/docs/system/ppc/pseries.rst index d9b65ad4e850..4c98a94f9add 100644 --- a/docs/system/ppc/pseries.rst +++ b/docs/system/ppc/pseries.rst @@ -32,14 +32,42 @@ Missing devices Firmware ======== +The pSeries platform in QEMU comes with 2 firmwares: + `SLOF `_ (Slimline Open Firmware) is an implementation of the `IEEE 1275-1994, Standard for Boot (Initialization Configuration) Firmware: Core Requirements and Practices `_. +SLOF performs bus scanning, PCI resource allocation, provides the client +interface to boot from block devices and network. + QEMU includes a prebuilt image of SLOF which is updated when a more recent version is required. +VOF (Virtual Open Firmware) is a minimalistic firmware to work with +``-machine pseries,x-vof=on``. When enabled, the firmware acts as a slim +shim and QEMU implements parts of the IEEE 1275 Open Firmware interface. + +VOF does not have device drivers, does not do PCI resource allocation and +relies on ``-kernel`` used with Linux kernels recent enough (v5.4+) +to PCI resource assignment. It is ideal to use with petitboot. + +Booting via ``-kernel`` supports the following: ++-------------------+-------------------+------------------+ +| kernel | pseries,x-vof=off | pseries,x-vof=on | ++===================+===================+==================+ +| vmlinux BE | ✓ | ✓ | ++-------------------+-------------------+------------------+ +| vmlinux LE | ✓ | ✓ | ++-------------------+-------------------+------------------+ +| zImage.pseries BE | x | ✓¹ | ++-------------------+-------------------+------------------+ +| zImage.pseries LE | ✓ | ✓ | ++-------------------+-------------------+------------------+ +Notes: +¹ must set kernel-addr=0 + Build directions ================