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=-8.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham 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 EC032C43613 for ; Thu, 20 Jun 2019 07:53:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BE7B52084A for ; Thu, 20 Jun 2019 07:53:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="iQsP9zZQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725912AbfFTHxb (ORCPT ); Thu, 20 Jun 2019 03:53:31 -0400 Received: from mail-wr1-f66.google.com ([209.85.221.66]:34943 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725877AbfFTHxb (ORCPT ); Thu, 20 Jun 2019 03:53:31 -0400 Received: by mail-wr1-f66.google.com with SMTP id m3so1962770wrv.2 for ; Thu, 20 Jun 2019 00:53:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=lsH4ngDT/IdZoy4iegWWymDr6AeZO2FoX+v0sL59S/I=; b=iQsP9zZQDrH362G1r/CZ1OPNk5wLoR8zIomFtOu2gAbskhz9nQ3HKeF6mJbP9rVPq3 tAOHNJFczTm3T4oD6EZ2i50NXcuGAKvRacF54rMVTPKdnm7wni2JW676wor1o5iPbGDv yy8v5jRp8SjvI1rVbjZAg2fiKlwp/jBGtEem1rRpOgx5ZcaDEdBInzp7uX1n4fuA3qL2 I1g/oKK8PEI831IvntNvoogM2pT6Gt7f6gsfdq7upihtRiXH6ZpiOdsVRy0o7GNyHmmT df0P3vRwYMeyJczZ6v9O2xS5PL/Dp848L0RfPE4JL7efkAjlFvRzVBwUqVd8GIl0j//v mAXw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=lsH4ngDT/IdZoy4iegWWymDr6AeZO2FoX+v0sL59S/I=; b=JziTHKQr9uOB5FGA4ZQK6Uf1g5DVIpJQ4pg3OuwRzS4TauV/CQ1hR0bA2UpwOXLpVl gShJU86GpTYdvhshpZ2UF2GLomBbg3xNv/K7EX6Aw1vRjOTv/39shiQIY3JngxbwDlQl 4e7I9mgeAWWh2yfIT0KMh7a0SOXkFpDfDTl8eY5o67iumJvcqR6n8r7aGzVulivnxXca 5f+0K4ESchXzLp9fAsVCkHTLEP0owWohDpYVgdRMqcj9/F13GJXR4zG6q4hqInBN6ZoM E9d4HOyRsI53Mtbgxoj5rbe3rLesWW34m5jYkCZ4svVSW7DSKjHOaX+Ye1ioz+IkvvIi InCQ== X-Gm-Message-State: APjAAAXJAfqv/PfBAu7rffCwwgtlU37TdtUzMQJSAZjxTLv3GTbIp0zH 5LlXugDanmBjlM4PDZhQnSIfWw== X-Google-Smtp-Source: APXvYqxbGKCKLUn3drTEpSz73VjgGxfZE9vrgDD+Nfc1mCFbKox+zYrpH9lA3V3XjjOS4BUgKN3W/g== X-Received: by 2002:adf:e311:: with SMTP id b17mr90917417wrj.11.1561017208729; Thu, 20 Jun 2019 00:53:28 -0700 (PDT) Received: from localhost ([2a02:8010:64d6:1:af8:edfb:42f3:6c14]) by smtp.gmail.com with ESMTPSA id a84sm5174055wmf.29.2019.06.20.00.53.27 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Thu, 20 Jun 2019 00:53:27 -0700 (PDT) Date: Thu, 20 Jun 2019 08:53:26 +0100 From: Graeme Gregory To: Ard Biesheuvel Cc: linux-arm-kernel@lists.infradead.org, linux-acpi@vger.kernel.org, catalin.marinas@arm.com, will.deacon@arm.com, lorenzo.pieralisi@arm.com, lee.jones@linaro.org, leif.lindholm@linaro.org Subject: Re: [RFC PATCH] acpi/arm64: ignore 5.1 FADTs that are reported as 5.0 Message-ID: <20190620075326.GA2148@xora-haswell.xora.org.uk> References: <20190619121831.7614-1-ard.biesheuvel@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190619121831.7614-1-ard.biesheuvel@linaro.org> User-Agent: Mutt/1.11.4 (2019-03-13) Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On Wed, Jun 19, 2019 at 02:18:31PM +0200, Ard Biesheuvel wrote: > Some Qualcomm Snapdragon based laptops built to run Microsoft Windows > are clearly ACPI 5.1 based, given that that is the first ACPI revision > that supports ARM, and introduced the FADT 'arm_boot_flags' field, > which has a non-zero field on those systems. > > So in these cases, infer from the ARM boot flags that the FADT must be > 5.1 or later, and treat it as 5.1. > Makes sense, I did actually see this in the wild in SBSA machine too once. Reviewed-by: Graeme Gregory > Signed-off-by: Ard Biesheuvel > --- > arch/arm64/kernel/acpi.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > > diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c > index 803f0494dd3e..7722e85fb69c 100644 > --- a/arch/arm64/kernel/acpi.c > +++ b/arch/arm64/kernel/acpi.c > @@ -155,10 +155,14 @@ static int __init acpi_fadt_sanity_check(void) > */ > if (table->revision < 5 || > (table->revision == 5 && fadt->minor_revision < 1)) { > - pr_err("Unsupported FADT revision %d.%d, should be 5.1+\n", > + pr_err(FW_BUG "Unsupported FADT revision %d.%d, should be 5.1+\n", > table->revision, fadt->minor_revision); > - ret = -EINVAL; > - goto out; > + > + if (!fadt->arm_boot_flags) { > + ret = -EINVAL; > + goto out; > + } > + pr_err("FADT has ARM boot flags set, assuming 5.1\n"); > } > > if (!(fadt->flags & ACPI_FADT_HW_REDUCED)) { > -- > 2.20.1 >