Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755152AbYLIOWU (ORCPT ); Tue, 9 Dec 2008 09:22:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754184AbYLIOQu (ORCPT ); Tue, 9 Dec 2008 09:16:50 -0500 Received: from outbound-wa4.frontbridge.com ([216.32.181.16]:52802 "EHLO WA4EHSOBE004.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752766AbYLIOQ3 (ORCPT ); Tue, 9 Dec 2008 09:16:29 -0500 X-BigFish: VPS3(zzzzzzz32i43j64h) X-Spam-TCS-SCL: 3:0 X-FB-SS: 5, X-WSS-ID: 0KBM4Z7-03-KKP-01 From: Joerg Roedel To: avi@redhat.com, mingo@redhat.com, dwmw2@infradead.org, gregkh@suse.de, weidong.han@intel.com CC: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Joerg Roedel Subject: [PATCH 06/21] AMD IOMMU: refactor completion wait handling into separate functions Date: Tue, 9 Dec 2008 15:16:03 +0100 Message-ID: <1228832178-13429-7-git-send-email-joerg.roedel@amd.com> X-Mailer: git-send-email 1.5.6.4 In-Reply-To: <1228832178-13429-6-git-send-email-joerg.roedel@amd.com> References: <20081209141143.GW12816@amd.com> <1228832178-13429-1-git-send-email-joerg.roedel@amd.com> <1228832178-13429-2-git-send-email-joerg.roedel@amd.com> <1228832178-13429-3-git-send-email-joerg.roedel@amd.com> <1228832178-13429-4-git-send-email-joerg.roedel@amd.com> <1228832178-13429-5-git-send-email-joerg.roedel@amd.com> <1228832178-13429-6-git-send-email-joerg.roedel@amd.com> X-OriginalArrivalTime: 09 Dec 2008 14:16:18.0896 (UTC) FILETIME=[B45C5D00:01C95A08] MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3378 Lines: 114 Impact: split one function into three The separate functions are required synchronize commands across all hardware IOMMUs in the system. Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu.c | 65 +++++++++++++++++++++++++++++-------------- 1 files changed, 44 insertions(+), 21 deletions(-) diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 11de0f1..db89001 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -195,6 +195,46 @@ static int iommu_queue_command(struct amd_iommu *iommu, struct iommu_cmd *cmd) } /* + * This function waits until an IOMMU has completed a completion + * wait command + */ +static void __iommu_wait_for_completion(struct amd_iommu *iommu) +{ + int ready = 0; + unsigned status = 0; + unsigned long i = 0; + + while (!ready && (i < EXIT_LOOP_COUNT)) { + ++i; + /* wait for the bit to become one */ + status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET); + ready = status & MMIO_STATUS_COM_WAIT_INT_MASK; + } + + /* set bit back to zero */ + status &= ~MMIO_STATUS_COM_WAIT_INT_MASK; + writel(status, iommu->mmio_base + MMIO_STATUS_OFFSET); + + if (unlikely((i == EXIT_LOOP_COUNT) && printk_ratelimit())) + printk(KERN_WARNING "AMD IOMMU: Completion wait loop failed\n"); +} + +/* + * This function queues a completion wait command into the command + * buffer of an IOMMU + */ +static int __iommu_completion_wait(struct amd_iommu *iommu) +{ + struct iommu_cmd cmd; + + memset(&cmd, 0, sizeof(cmd)); + cmd.data[0] = CMD_COMPL_WAIT_INT_MASK; + CMD_SET_TYPE(&cmd, CMD_COMPL_WAIT); + + return __iommu_queue_command(iommu, &cmd); +} + +/* * This function is called whenever we need to ensure that the IOMMU has * completed execution of all commands we sent. It sends a * COMPLETION_WAIT command and waits for it to finish. The IOMMU informs @@ -203,14 +243,8 @@ static int iommu_queue_command(struct amd_iommu *iommu, struct iommu_cmd *cmd) */ static int iommu_completion_wait(struct amd_iommu *iommu) { - int ret = 0, ready = 0; - unsigned status = 0; - struct iommu_cmd cmd; - unsigned long flags, i = 0; - - memset(&cmd, 0, sizeof(cmd)); - cmd.data[0] = CMD_COMPL_WAIT_INT_MASK; - CMD_SET_TYPE(&cmd, CMD_COMPL_WAIT); + int ret = 0; + unsigned long flags; spin_lock_irqsave(&iommu->lock, flags); @@ -219,24 +253,13 @@ static int iommu_completion_wait(struct amd_iommu *iommu) iommu->need_sync = 0; - ret = __iommu_queue_command(iommu, &cmd); + ret = __iommu_completion_wait(iommu); if (ret) goto out; - while (!ready && (i < EXIT_LOOP_COUNT)) { - ++i; - /* wait for the bit to become one */ - status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET); - ready = status & MMIO_STATUS_COM_WAIT_INT_MASK; - } - - /* set bit back to zero */ - status &= ~MMIO_STATUS_COM_WAIT_INT_MASK; - writel(status, iommu->mmio_base + MMIO_STATUS_OFFSET); + __iommu_wait_for_completion(iommu); - if (unlikely((i == EXIT_LOOP_COUNT) && printk_ratelimit())) - printk(KERN_WARNING "AMD IOMMU: Completion wait loop failed\n"); out: spin_unlock_irqrestore(&iommu->lock, flags); -- 1.5.6.4 -- 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/