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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 63518C4167D for ; Fri, 3 Nov 2023 10:43:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233083AbjKCKna (ORCPT ); Fri, 3 Nov 2023 06:43:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229941AbjKCKn3 (ORCPT ); Fri, 3 Nov 2023 06:43:29 -0400 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 31692123; Fri, 3 Nov 2023 03:43:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=qAFZIXflbodoDXB4lem1gRSjUMp78Vi8Q3DaxqkIfhU=; b=knJhz0h/4TAM6ag6xJdTXGbVEQ jgaGe2cRFDXkZBUAzAUvwa++0RzEJhjwejiB9ms9fjYudo3W3AgTALd3sppJLSVskUZfJhr2dhoPv KjY6HeswmZf3z1GTqmMzRr2u2Q10Un8ozUX8l1hVZs0HbtdRFL1pYzSqlalYpE+yys3H2YZLu1OhU xcqVnpomu08Dq/lmzTRZQzzYNepazRsgwMoaW/dZ7rNvJfHkyrSKh00WiQB1GTUfBb7ctuTprn5xj uB/Zj7lX7WxlcM3icqvf8dhXvDts6XMzbMioJ53frMbOmF/lp84VWErHzsr1//WEBRYjqdphC9Fy3 gA/7nWgA==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:38622) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1qyrdz-0005RQ-1z; Fri, 03 Nov 2023 10:43:15 +0000 Received: from linux by shell.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1qyrdz-0008KY-04; Fri, 03 Nov 2023 10:43:15 +0000 Date: Fri, 3 Nov 2023 10:43:14 +0000 From: "Russell King (Oracle)" To: Jonathan Cameron Cc: James Morse , linux-pm@vger.kernel.org, loongarch@lists.linux.dev, linux-acpi@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, kvmarm@lists.linux.dev, x86@kernel.org, Salil Mehta , Jean-Philippe Brucker , jianyong.wu@arm.com, justin.he@arm.com Subject: Re: [RFC PATCH v2 15/35] ACPI: processor: Add support for processors described as container packages Message-ID: References: <20230913163823.7880-1-james.morse@arm.com> <20230913163823.7880-16-james.morse@arm.com> <20230914145353.000072e2@Huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230914145353.000072e2@Huawei.com> Sender: Russell King (Oracle) Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org On Thu, Sep 14, 2023 at 02:53:53PM +0100, Jonathan Cameron wrote: > On Wed, 13 Sep 2023 16:38:03 +0000 > James Morse wrote: > > > ACPI has two ways of describing processors in the DSDT. Either as a device > > object with HID ACPI0007, or as a type 'C' package inside a Processor > > Container. The ACPI processor driver probes CPUs described as devices, but > > not those described as packages. > > > > Specification reference needed... > > Terminology wise, I'd just refer to Processor() objects as I think they > are named objects rather than data terms like a package (Which include > a PkgLength etc) I'm not sure what kind of reference you want for the above. Looking in ACPI 6.5, I've found in 5.2.12: "Starting with ACPI Specification 6.3, the use of the Processor() object was deprecated. Only legacy systems should continue with this usage. On the Itanium architecture only, a _UID is provided for the Processor() that is a string object. This usage of _UID is also deprecated since it can preclude an OSPM from being able to match a processor to a non-enumerable device, such as those defined in the MADT. From ACPI Specification 6.3 onward, all processor objects for all architectures except Itanium must now use Device() objects with an _HID of ACPI0007, and use only integer _UID values." Also, there is: https://uefi.org/specs/ACPI/6.5/08_Processor_Configuration_and_Control.html#declaring-processors Unfortunately, using the search facility on that site to try and find Processor() doesn't work - it appears to strip the "()" characters from the search (which is completely dumb, why do search facilities do that?) > > The missing probe for CPUs described as packages creates a problem for > > moving the cpu_register() calls into the acpi_processor driver, as CPUs > > described like this don't get registered, leading to errors from other > > subsystems when they try to add new sysfs entries to the CPU node. > > (e.g. topology_sysfs_init()'s use of topology_add_dev() via cpuhp) > > > > To fix this, parse the processor container and call acpi_processor_add() > > for each processor that is discovered like this. The processor container > > handler is added with acpi_scan_add_handler(), so no detach call will > > arrive. > > > > Qemu TCG describes CPUs using packages in a processor container. > > processor terms in a processor container. Are you wanting this to be: "Qemu TCG describes CPUs using processor terms in a processor container." ? Searching the ACPI spec for "processor terms" (with or without quotes) only brings up results for "terms" - yet another reason to hate site- provided search facilities, I don't know why sites bother. :( -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!