From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f53.google.com (mail-wm1-f53.google.com [209.85.128.53]) by mx.groups.io with SMTP id smtpd.web11.6049.1637760311287845497 for ; Wed, 24 Nov 2021 05:25:11 -0800 Authentication-Results: mx.groups.io; dkim=pass header.i=@nuviainc-com.20210112.gappssmtp.com header.s=20210112 header.b=PUtekaKl; spf=pass (domain: nuviainc.com, ip: 209.85.128.53, mailfrom: leif@nuviainc.com) Received: by mail-wm1-f53.google.com with SMTP id i12so2334629wmq.4 for ; Wed, 24 Nov 2021 05:25:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nuviainc-com.20210112.gappssmtp.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=1i1tQCmR5qEKLzVBN2kA5WFAo2jm7PGPHdPzftK37FI=; b=PUtekaKlonfUtWE670pPJQmdMi8HGyp7slJK6tgnkPpkRnb2cVL/WkyHyurRt4Rc2D I1jzQle3KZrq0urNmurK33bkxpTOsJL2axflxdpRP7EFHiEOzg8l6VnyrrZXAamB2cif K1XendEZTXp1ZVsU4ULX/dv9M7MFHNXHqiixhdrCYiyGOt7SRGnBnhezeUxwNlCIE2jY q7AZ6nAnnYyizlywdx+mSFd5N/SyremEUQu9Pov3WXrMEwoyddUzga6em1Fs1xNer3ql iwzBAFWceIp27mPnRDyGQJzI1NpohFFDeIwYt3iINixeuqlTLn/MnVGL+SHBs4IrMVay osFw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=1i1tQCmR5qEKLzVBN2kA5WFAo2jm7PGPHdPzftK37FI=; b=SSMS3Sa4IG8WAvSLAfvvA9KMzFVQql5aL3imyOsxj4VbWZVlpE0RyYTBw1yK+3SZ+x JNu7F9biiYSpgBuR3MVg9WIzMv7fu0nlKtE839eyBGZdMp7k062o5peAGENncPHa810s VVEy/Z/1gRTYQztPXd9IBQer78b0+dK4VzL7XHMcbX5ju0M4bgxRQjwCfU6VHEcYn735 lPixgcBQ9wc+gtUJCmsWv7Rfk0oPE1VudTJHlubiSU3/9brwQ3j6ipwK6r5VB6MkUrbS hwE68sAhAJJYZbmiE43CC3DlCly8Qd9R50gUUVjWY4eLJwrRHALwgkplyXtgECS9scjD 4Czw== X-Gm-Message-State: AOAM530Z44r8GFUomSZkpOvnviLrUM/JVipViNzvu454NuFbOB4myFVR 0T4CI6NkHvvVjzwhefGA/2a3yQ== X-Google-Smtp-Source: ABdhPJxezZtcjg4gfzx69uQWsjSiqzvMjhxotI9Ag4vjRiSo985j7NtRuF5Cryyh1/pvlccsrnLu3w== X-Received: by 2002:a05:600c:1f19:: with SMTP id bd25mr15034442wmb.75.1637760309545; Wed, 24 Nov 2021 05:25:09 -0800 (PST) Return-Path: Received: from leviathan (cpc92314-cmbg19-2-0-cust559.5-4.cable.virginm.net. [82.11.186.48]) by smtp.gmail.com with ESMTPSA id c4sm15282862wrr.37.2021.11.24.05.25.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 24 Nov 2021 05:25:08 -0800 (PST) Date: Wed, 24 Nov 2021 13:25:06 +0000 From: "Leif Lindholm" To: Ard Biesheuvel Cc: Sami Mujawar , Ard Biesheuvel , edk2-devel-groups-io , Rebecca Cran , Gerd Hoffmann , Michael Kinney , "Liming Gao (Byosoft address)" , Zhiguang Liu , Jiewen Yao , Jian J Wang , Matteo.Carlini@arm.com, Akanksha.Jain2@arm.com, Ben.Adderson@arm.com, nd Subject: Re: [PATCH v2 2/8] ArmPkg: PCD to select conduit for monitor calls Message-ID: References: <20211116113301.31088-1-sami.mujawar@arm.com> <20211116113301.31088-3-sami.mujawar@arm.com> MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Nov 24, 2021 at 14:07:22 +0100, Ard Biesheuvel wrote: > On Wed, 24 Nov 2021 at 14:05, Leif Lindholm wrote: > > > > On Wed, Nov 24, 2021 at 14:03:51 +0100, Ard Biesheuvel wrote: > > > On Wed, 24 Nov 2021 at 13:07, Leif Lindholm wrote: > > > > > > > > Ard - how does this interact with e.g. ArmVirtPsciResetSystemLib, > > > > which reads its conduit out of the DT passed to it by QEMU? > > > > > > > > > > As long as ArmCallSmc() and ArmCallHvc() continue to exist and behave > > > as before, I don't think those libraries are affected. > > > > Well, I was thinking more that you can now end up with a firmware > > build where the conduit is sometimes dynamically determined, and > > sometimes compile-time determined. > > There is nothing wrong with that by itself: if you have a DT that > describes this, it makes sense to carry support for both. If the bare > metal you are targetting only ever uses SMC, no need for the discovery > and a PCD is fine. > > Question remains whether this PCD could/should be configurable as > dynamic, so we collapse the static/dynamic options into a single PCD > based choice. That would feel cleaner. Although not required for this set. / Leif