From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933567AbZIDJqr (ORCPT ); Fri, 4 Sep 2009 05:46:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933324AbZIDJqp (ORCPT ); Fri, 4 Sep 2009 05:46:45 -0400 Received: from va3ehsobe005.messaging.microsoft.com ([216.32.180.15]:48577 "EHLO VA3EHSOBE006.bigfish.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933559AbZIDJpl (ORCPT ); Fri, 4 Sep 2009 05:45:41 -0400 X-SpamScore: 3 X-BigFish: VPS3(zzzz1202hzzz32i203h43j62h) X-Spam-TCS-SCL: 1:0 X-WSS-ID: 0KPFXRX-02-2ET-02 X-M-MSG: From: Joerg Roedel To: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org CC: Joerg Roedel Subject: [PATCH 5/8] x86/amd-iommu: Add reset function for command buffers Date: Fri, 4 Sep 2009 11:44:39 +0200 Message-ID: <1252057482-32207-6-git-send-email-joerg.roedel@amd.com> X-Mailer: git-send-email 1.6.3.3 In-Reply-To: <1252057482-32207-1-git-send-email-joerg.roedel@amd.com> References: <1252057482-32207-1-git-send-email-joerg.roedel@amd.com> X-OriginalArrivalTime: 04 Sep 2009 09:44:45.0429 (UTC) FILETIME=[55D15A50:01CA2D44] 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 This patch factors parts of the command buffer initialization code into a seperate function which can be used to reset the command buffer later. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/amd_iommu_types.h | 3 +++ arch/x86/kernel/amd_iommu_init.c | 20 +++++++++++++++----- 2 files changed, 18 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h index 0c878ca..c54bc97 100644 --- a/arch/x86/include/asm/amd_iommu_types.h +++ b/arch/x86/include/asm/amd_iommu_types.h @@ -457,4 +457,7 @@ static inline void amd_iommu_stats_init(void) { } #endif /* CONFIG_AMD_IOMMU_STATS */ +/* some function prototypes */ +extern void amd_iommu_reset_cmd_buffer(struct amd_iommu *iommu); + #endif /* _ASM_X86_AMD_IOMMU_TYPES_H */ diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c index c1b17e9..1752afe 100644 --- a/arch/x86/kernel/amd_iommu_init.c +++ b/arch/x86/kernel/amd_iommu_init.c @@ -435,6 +435,20 @@ static u8 * __init alloc_command_buffer(struct amd_iommu *iommu) } /* + * This function resets the command buffer if the IOMMU stopped fetching + * commands from it. + */ +void amd_iommu_reset_cmd_buffer(struct amd_iommu *iommu) +{ + iommu_feature_disable(iommu, CONTROL_CMDBUF_EN); + + writel(0x00, iommu->mmio_base + MMIO_CMD_HEAD_OFFSET); + writel(0x00, iommu->mmio_base + MMIO_CMD_TAIL_OFFSET); + + iommu_feature_enable(iommu, CONTROL_CMDBUF_EN); +} + +/* * This function writes the command buffer address to the hardware and * enables it. */ @@ -450,11 +464,7 @@ static void iommu_enable_command_buffer(struct amd_iommu *iommu) memcpy_toio(iommu->mmio_base + MMIO_CMD_BUF_OFFSET, &entry, sizeof(entry)); - /* set head and tail to zero manually */ - writel(0x00, iommu->mmio_base + MMIO_CMD_HEAD_OFFSET); - writel(0x00, iommu->mmio_base + MMIO_CMD_TAIL_OFFSET); - - iommu_feature_enable(iommu, CONTROL_CMDBUF_EN); + amd_iommu_reset_cmd_buffer(iommu); } static void __init free_command_buffer(struct amd_iommu *iommu) -- 1.6.3.3