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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 A940EC352A3 for ; Mon, 10 Feb 2020 10:38:11 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 6B9372070A for ; Mon, 10 Feb 2020 10:38:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="hGaQLPMG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6B9372070A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:59810 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j16SA-0005KU-Ir for qemu-devel@archiver.kernel.org; Mon, 10 Feb 2020 05:38:10 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:52855) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j16Ra-0004uC-Ac for qemu-devel@nongnu.org; Mon, 10 Feb 2020 05:37:35 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j16RZ-0007Lv-1V for qemu-devel@nongnu.org; Mon, 10 Feb 2020 05:37:34 -0500 Received: from mail-ot1-x343.google.com ([2607:f8b0:4864:20::343]:46067) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1j16RY-0007Ki-Ri for qemu-devel@nongnu.org; Mon, 10 Feb 2020 05:37:32 -0500 Received: by mail-ot1-x343.google.com with SMTP id 59so5792673otp.12 for ; Mon, 10 Feb 2020 02:37:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=uzVWV3C/8LNNtAOE6wVRXtapr6EtAmKiHWsn6cUwA9Y=; b=hGaQLPMG7JEj8SrmE6nj8VbWErO5zNBnNlDfSPYyUdb2eHA+sMrLHIHZgyrJZ66gJI QwXpCLHzQeVBfi3wnOHgMnDR+FOuFFBXD9RwxlEyidN/F3rVeOhwhAOovJ2L9cKJxO63 m/oAwjBPUdUC5N1gvDKHcCG7gW2iLcytzEezt9savoDZlBvd4T5prextQtHQfkqj12ai m3Ps2f+xqJVGUgbF+cVDzPV1SvszzAjdqqIPwFyg81gpeT8+c44R3LM+qzaM8cCoPIbu qR65SRY/bG6HayCdnhEtuLO9Up8OJYMcxwGAbQ1pwVPlpmPocXadfunpP6iK0FlxWbdL Tenw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=uzVWV3C/8LNNtAOE6wVRXtapr6EtAmKiHWsn6cUwA9Y=; b=L9wtUmdMpCIjsXJwlYlR8PNvIulA9TxJ43Y3L+MQBKrhbuFVZ1Y+sLI9HjNUtjI5LF 5rQe2TiIyb/7sO94TPuqPzcuLcuGcChaXsPZEu4ipMAcieJoXvxARNFqi7DSekNqxG74 GYJFWFhPjeg9lzUTB7y0qy51xpacDwaUPwd6WtG54x3EOWYA6hO0UR4Ydh0weif7+Z5U YN1c7p8eRmD00ouNtnN6YlNZrWtlD1jn03omka0QvRSsbDFRzFrY1CAizbu2DdO+gCCT UKP6C6Z6GXYOLug4506coM0vbfRWjrAneftRP78seCrtdYR1K0fp0MQABp1tiDKuJDmk oOOQ== X-Gm-Message-State: APjAAAXl4UtM52NUagwh+J8eP71uWxa1LuBuRk0ozzJSO6sEu9LOPgZv IUmnr0EpdgLoTl1lN26L01i4lMBKi0EDPcN1HmzwFA== X-Google-Smtp-Source: APXvYqxsbk92FMKsqrsqlVC4xvNTJxp2zmxDOPd32LlNMJp4G76tzq1JHdMuvAd5ADWyuJrkb+9uiJsuC1m3pFxBP+w= X-Received: by 2002:a05:6830:13da:: with SMTP id e26mr514876otq.97.1581331051464; Mon, 10 Feb 2020 02:37:31 -0800 (PST) MIME-Version: 1.0 References: <8420784f-b4c7-9864-8534-b94dbc5f74ff@redhat.com> <71d1cc16-f07d-481d-096b-17ee326157bb@ozlabs.ru> <20200205060634.GI60221@umbus.fritz.box> <62d62fab-46a4-240b-037b-409ba859b93d@redhat.com> <47e6a49d-f1c7-aaf6-b9ef-7e81773cff6e@ozlabs.ru> <8993c6b4-2a2c-b7e5-8342-4db480d0af9d@redhat.com> <20200210073008.GE22584@umbus.fritz.box> In-Reply-To: <20200210073008.GE22584@umbus.fritz.box> From: Peter Maydell Date: Mon, 10 Feb 2020 10:37:19 +0000 Message-ID: Subject: Re: VW ELF loader To: David Gibson Content-Type: text/plain; charset="UTF-8" X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:4864:20::343 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Thomas Huth , Alexey Kardashevskiy , qemu-devel , Cornelia Huck , Christian Borntraeger , Paolo Bonzini , Stefano Garzarella Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, 10 Feb 2020 at 07:56, David Gibson wrote: > On Fri, Feb 07, 2020 at 12:45:20AM +0100, Paolo Bonzini wrote: > > Every platform that QEMU supports is just using a firmware to do > > firmware things; it can be U-Boot, EDK-2, SLOF, SeaBIOS, qboot, with > > varying level of complexity. Some are doing -kernel in QEMU rather than > > firmware, but that's where things end. > > Well, yeah, but AIUI those platforms actually have a defined hardware > environment on which the firmware is running. For PAPR we don't, we > *only* have a specification for the "hardware"+"firmware" environment > as seen by the OS together. (The below is not intended to be a prescription for what PPC should do, just some background info about what we're doing with Arm currently.) For Arm our 'virt' board is drifting a bit towards doing some 'firmware' ABIs in QEMU -- currently this mostly means PSCI (for CPU power on/off, system reset, etc), but there have been proposals for other firmware ABIs that are hard to implement in guest firmware. I tend to agree with Paolo in principle that where possible keeping QEMU to "we implement some hardware emulation" and having firmware running in the guest is a nicer separation of concerns, though, so for Arm I'd like to avoid ending up with a lot of firmware-equivalent code in QEMU. FWIW for the Arm 'virt' board there is no defined hardware spec in the "handed down from elsewhere" sense -- so we defined our own (and some mechanisms for passing the device tree description of it into the guest firmware). thanks -- PMM