Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753877Ab2EHKFR (ORCPT ); Tue, 8 May 2012 06:05:17 -0400 Received: from terminus.zytor.com ([198.137.202.10]:53429 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751790Ab2EHKFP (ORCPT ); Tue, 8 May 2012 06:05:15 -0400 Date: Tue, 8 May 2012 03:05:02 -0700 From: tip-bot for Shai Fultheim Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, shai@scalemp.com, ido@wizery.com, tglx@linutronix.de Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, shai@scalemp.com, tglx@linutronix.de, ido@wizery.com In-Reply-To: <1336462455-22544-1-git-send-email-ido@wizery.com> References: <1336462455-22544-1-git-send-email-ido@wizery.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/platform] vsmp: Fix number of CPUs when vsmp is disabled Git-Commit-ID: 824a6ae65f085255464155760cb9628a2f0deb29 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.6 (terminus.zytor.com [127.0.0.1]); Tue, 08 May 2012 03:05:09 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2865 Lines: 100 Commit-ID: 824a6ae65f085255464155760cb9628a2f0deb29 Gitweb: http://git.kernel.org/tip/824a6ae65f085255464155760cb9628a2f0deb29 Author: Shai Fultheim AuthorDate: Tue, 8 May 2012 10:34:15 +0300 Committer: Ingo Molnar CommitDate: Tue, 8 May 2012 11:24:45 +0200 vsmp: Fix number of CPUs when vsmp is disabled In case CONFIG_X86_VSMP is not set, limit the number of CPUs to the number of CPUs of the first board. Signed-off-by: Shai Fultheim [ido@wizery.com: rebased, fixed minor coding-style issues] Signed-off-by: Ido Yariv Link: http://lkml.kernel.org/r/1336462455-22544-1-git-send-email-ido@wizery.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/vsmp_64.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 43 insertions(+), 0 deletions(-) diff --git a/arch/x86/kernel/vsmp_64.c b/arch/x86/kernel/vsmp_64.c index a1d804b..6aa0d59 100644 --- a/arch/x86/kernel/vsmp_64.c +++ b/arch/x86/kernel/vsmp_64.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include @@ -22,6 +23,8 @@ #include #include +#define TOPOLOGY_REGISTER_OFFSET 0x10 + #if defined CONFIG_PCI && defined CONFIG_PARAVIRT /* * Interrupt control on vSMPowered systems: @@ -149,12 +152,52 @@ int is_vsmp_box(void) return 0; } #endif + +static void __init vsmp_cap_cpus(void) +{ + void __iomem *address; + unsigned int cfg, topology, node_shift, maxcpus; + +#ifdef CONFIG_X86_VSMP + /* VSMP is enabled, no need to cap cpus */ + return; +#endif + + /* + * CONFIG_X86_VSMP is not configured, so limit the number CPUs to the + * ones present in the first board, unless explicitly overridden by + * setup_max_cpus + */ + if (setup_max_cpus != NR_CPUS) + return; + + /* Read the vSMP Foundation topology register */ + cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0); + address = early_ioremap(cfg + TOPOLOGY_REGISTER_OFFSET, 4); + if (WARN_ON(!address)) + return; + + topology = readl(address); + node_shift = (topology >> 16) & 0x7; + if (!node_shift) + /* The value 0 should be decoded as 8 */ + node_shift = 8; + maxcpus = (topology & ((1 << node_shift) - 1)) + 1; + + pr_info("vSMP CTL: Capping CPUs to %d (CONFIG_X86_VSMP is unset)\n", + maxcpus); + setup_max_cpus = maxcpus; + early_iounmap(address, 4); +} + void __init vsmp_init(void) { detect_vsmp_box(); if (!is_vsmp_box()) return; + vsmp_cap_cpus(); + set_vsmp_pv_ops(); return; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/