iommu/vt-d: Disable translation if already enabled

[firefly-linux-kernel-4.4.55.git] / drivers / iommu / dmar.c

diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 9f8aa07360baa168404996b66d746f7099fd6eae..f7890edb22f5e9f8c5697f37c72ed6c328dae1e6 100644 (file)
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -645,7 +645,7 @@ out:
 int alloc_iommu(struct dmar_drhd_unit *drhd)
 {
        struct intel_iommu *iommu;
-       u32 ver;
+       u32 ver, sts;
        static int iommu_allocated = 0;
        int agaw = 0;
        int msagaw = 0;
@@ -695,6 +695,15 @@ int alloc_iommu(struct dmar_drhd_unit *drhd)
                (unsigned long long)iommu->cap,
                (unsigned long long)iommu->ecap);
 
+       /* Reflect status in gcmd */
+       sts = readl(iommu->reg + DMAR_GSTS_REG);
+       if (sts & DMA_GSTS_IRES)
+               iommu->gcmd |= DMA_GCMD_IRE;
+       if (sts & DMA_GSTS_TES)
+               iommu->gcmd |= DMA_GCMD_TE;
+       if (sts & DMA_GSTS_QIES)
+               iommu->gcmd |= DMA_GCMD_QIE;
+
        raw_spin_lock_init(&iommu->register_lock);
 
        drhd->iommu = iommu;