From patchwork Tue Jun 17 05:29:41 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiang Liu X-Patchwork-Id: 360333 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 70E52140087 for ; Tue, 17 Jun 2014 15:31:41 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932148AbaFQF1O (ORCPT ); Tue, 17 Jun 2014 01:27:14 -0400 Received: from mga14.intel.com ([192.55.52.115]:20999 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755481AbaFQF1K (ORCPT ); Tue, 17 Jun 2014 01:27:10 -0400 Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga103.fm.intel.com with ESMTP; 16 Jun 2014 22:22:02 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.01,492,1400050800"; d="scan'208";a="549015065" Received: from gerry-dev.bj.intel.com ([10.238.158.74]) by fmsmga001.fm.intel.com with ESMTP; 16 Jun 2014 22:27:04 -0700 From: Jiang Liu To: Benjamin Herrenschmidt , Thomas Gleixner , Grant Likely , Ingo Molnar , "H. Peter Anvin" , "Rafael J. Wysocki" , Bjorn Helgaas , Randy Dunlap , Yinghai Lu , x86@kernel.org, Jiang Liu Cc: Konrad Rzeszutek Wilk , Andrew Morton , Tony Luck , Joerg Roedel , Paul Gortmaker , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org, Sebastian Andrzej Siewior , Ingo Molnar Subject: [RFC Patch V2 02/16] x86, ioapic: Find usable ioapic id for 64bit. Date: Tue, 17 Jun 2014 13:29:41 +0800 Message-Id: <1402982995-13747-3-git-send-email-jiang.liu@linux.intel.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1402982995-13747-1-git-send-email-jiang.liu@linux.intel.com> References: <1402982995-13747-1-git-send-email-jiang.liu@linux.intel.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Yinghai Lu Checking the id in register, if that is duplicated, will pick one and update id register. Signed-off-by: Yinghai Lu Cc: Joerg Roedel Cc: Konrad Rzeszutek Wilk Cc: Sebastian Andrzej Siewior Signed-off-by: Jiang Liu --- arch/x86/kernel/apic/io_apic.c | 38 +++++++++++++++++++++++++++++++++----- 1 file changed, 33 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index e97ec28f5269..e56bb94cd32a 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -3566,26 +3566,54 @@ static int __init io_apic_get_unique_id(int ioapic, int apic_id) return apic_id; } -static u8 __init io_apic_unique_id(u8 id) +static u8 io_apic_unique_id(int idx, u8 id) { if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && !APIC_XAPIC(apic_version[boot_cpu_physical_apicid])) - return io_apic_get_unique_id(nr_ioapics, id); + return io_apic_get_unique_id(idx, id); else return id; } #else -static u8 __init io_apic_unique_id(u8 id) +static u8 io_apic_unique_id(int idx, u8 id) { int i; + u8 new_id; + unsigned long flags; DECLARE_BITMAP(used, 256); + union IO_APIC_reg_00 reg_00; bitmap_zero(used, 256); for_each_ioapic(i) __set_bit(mpc_ioapic_id(i), used); if (!test_bit(id, used)) return id; - return find_first_zero_bit(used, 256); + + /* check register at first */ + raw_spin_lock_irqsave(&ioapic_lock, flags); + reg_00.raw = io_apic_read(idx, 0); + raw_spin_unlock_irqrestore(&ioapic_lock, flags); + new_id = reg_00.bits.ID; + if (!test_bit(new_id, used)) { + apic_printk(APIC_VERBOSE, KERN_INFO + "IOAPIC[%d]: Using reg apic_id %d instead of %d\n", + idx, new_id, id); + return new_id; + } + + new_id = find_first_zero_bit(used, 256); + reg_00.bits.ID = new_id; + raw_spin_lock_irqsave(&ioapic_lock, flags); + io_apic_write(idx, 0, reg_00.raw); + reg_00.raw = io_apic_read(idx, 0); + raw_spin_unlock_irqrestore(&ioapic_lock, flags); + + /* Sanity check */ + if (reg_00.bits.ID != new_id) + pr_warn("IOAPIC[%d]: Unable to change apic_id to %d!\n", + idx, new_id); + + return new_id; } #endif @@ -3851,7 +3879,7 @@ void __init mp_register_ioapic(int id, u32 address, u32 gsi_base, return; } - ioapics[idx].mp_config.apicid = io_apic_unique_id(id); + ioapics[idx].mp_config.apicid = io_apic_unique_id(idx, id); ioapics[idx].mp_config.apicver = io_apic_get_version(idx); /*