From: Joerg Roedel <joerg.roedel@amd.com>
Date: Wed, 17 Dec 2008 14:06:01 +0000 (+0100)
Subject: AMD IOMMU: set cmd buffer pointers to zero manually
X-Git-Tag: v2.6.28~17^2~1^2~1
X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=cf558d25e5c9f70fa0279c9b7b8b4aed7cae9bd4;p=linux-2.6-omap-h63xx.git

AMD IOMMU: set cmd buffer pointers to zero manually

Impact: set cmd buffer head and tail pointers to zero in case nobody else did

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---

diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c
index c90a15eba5c..c6cc22815d3 100644
--- a/arch/x86/kernel/amd_iommu_init.c
+++ b/arch/x86/kernel/amd_iommu_init.c
@@ -427,6 +427,10 @@ static u8 * __init alloc_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);
 
 	return cmd_buf;