From cf558d25e5c9f70fa0279c9b7b8b4aed7cae9bd4 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Wed, 17 Dec 2008 15:06:01 +0100 Subject: [PATCH] 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 --- arch/x86/kernel/amd_iommu_init.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c index c90a15e..c6cc228 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; -- 1.7.9.5