From patchwork Fri Feb 19 13:08:28 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Chamberlain X-Patchwork-Id: 8360851 Return-Path: X-Original-To: patchwork-xen-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 06B719F38B for ; Fri, 19 Feb 2016 13:11:17 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 726392049E for ; Fri, 19 Feb 2016 13:11:15 +0000 (UTC) Received: from lists.xen.org (lists.xenproject.org [50.57.142.19]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3484020412 for ; Fri, 19 Feb 2016 13:11:14 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1aWkni-0006h0-CU; Fri, 19 Feb 2016 13:08:50 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1aWknh-0006gj-Kp for xen-devel@lists.xensource.com; Fri, 19 Feb 2016 13:08:49 +0000 Received: from [193.109.254.147] by server-14.bemta-14.messagelabs.com id 85/3B-07165-0E317C65; Fri, 19 Feb 2016 13:08:48 +0000 X-Env-Sender: mcgrof@kernel.org X-Msg-Ref: server-5.tower-27.messagelabs.com!1455887326!25171471!1 X-Originating-IP: [198.145.29.136] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 7.35.1; banners=-,-,- X-VirusChecked: Checked Received: (qmail 39524 invoked from network); 19 Feb 2016 13:08:48 -0000 Received: from mail.kernel.org (HELO mail.kernel.org) (198.145.29.136) by server-5.tower-27.messagelabs.com with DHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 19 Feb 2016 13:08:48 -0000 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9FFEC203F7; Fri, 19 Feb 2016 13:08:45 +0000 (UTC) Received: from garbanzo.do-not-panic.com (c-73-15-241-2.hsd1.ca.comcast.net [73.15.241.2]) (using TLSv1.2 with cipher AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 82AF120494; Fri, 19 Feb 2016 13:08:44 +0000 (UTC) From: "Luis R. Rodriguez" To: bp@alien8.de Date: Fri, 19 Feb 2016 05:08:28 -0800 Message-Id: <1455887316-9223-2-git-send-email-mcgrof@kernel.org> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1455887316-9223-1-git-send-email-mcgrof@kernel.org> References: <1455887316-9223-1-git-send-email-mcgrof@kernel.org> X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Cc: rusty@rustcorp.com.au, x86@kernel.org, linux-kernel@vger.kernel.org, luto@amacapital.net, "Luis R. Rodriguez" , xen-devel@lists.xensource.com, david.vrabel@citrix.com, boris.ostrovsky@oracle.com, Andy Shevchenko Subject: [Xen-devel] [PATCH 1/9] x86/boot: enumerate documentation for the x86 hardware_subarch X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org X-Virus-Scanned: ClamAV using ClamSMTP Although hardware_subarch has been in place since the x86 boot protocol 2.07 it hasn't been used much. Enumerate current possible values to avoid misuses and help with semantics later at boot time should this be used further. Cc: Andy Shevchenko Signed-off-by: Luis R. Rodriguez --- arch/x86/include/uapi/asm/bootparam.h | 32 +++++++++++++++++++++++++++++++- 1 file changed, 31 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h index 329254373479..dbfb9406436b 100644 --- a/arch/x86/include/uapi/asm/bootparam.h +++ b/arch/x86/include/uapi/asm/bootparam.h @@ -157,7 +157,37 @@ struct boot_params { __u8 _pad9[276]; /* 0xeec */ } __attribute__((packed)); -enum { +/** + * enum x86_hardware_subarch - x86 hardware subarchitecture + * + * The x86 hardware_subarch and hardware_subarch_data were added as of the x86 + * boot protocol 2.07 to help distinguish and supports custom x86 boot + * sequences. This enum represents accepted values for the x86 + * hardware_subarch. Custom x86 boot sequences (not X86_SUBARCH_PC) do not have + * or simply do not make use of natural stubs like BIOS or EFI, the + * hardware_subarch can be used on the Linux entry path to revector to a + * subarchitecture stub when needed. This subarchitecture stub can be used to + * set up Linux boot parameters or for special care to account for nonstandard + * handling of page tables. + * + * KVM and Xen HVM do not have a subarch as these are expected to follow + * standard x86 boot entries. If there is a genuine need for "hypervisor" type + * that should be considered separately in the future. + * + * @X86_SUBARCH_PC: Should be used if the hardware is enumerable using standard + * PC mechanisms (PCI, ACPI) and doesn't need a special boot flow. + * @X86_SUBARCH_LGUEST: Used for x86 hypervisor demo, lguest + * @X86_SUBARCH_LGUEST: Used for x86 hypervisor demo, lguest + * @X86_SUBARCH_XEN: Used for Xen guest types which follow the PV boot path, + * which start at asm startup_xen() entry point and later jump to the C + * xen_start_kernel() entry point. + * @X86_SUBARCH_INTEL_MID: Used for Intel MID (Mobile nternet Device) platform + * systems which do not have the PCI legacy interfaces. + * @X86_SUBARCH_CE4100: Used for Intel CE media processor (CE4100) SOC for + * for settop boxes and media devices, the use of a subarch for CE4100 + * is more of a hack... + */ +enum x86_hardware_subarch { X86_SUBARCH_PC = 0, X86_SUBARCH_LGUEST, X86_SUBARCH_XEN,