2 files changed, 24 insertions, 1 deletions

diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index 31fa6c92aa5e..585e188c1746 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -692,6 +692,23 @@ static int iommu_flush_iotlb_psi(struct intel_iommu *iommu, u16 did,
                 DMA_TLB_PSI_FLUSH, non_present_entry_flush);
 }
 
+static void iommu_disable_protect_mem_regions(struct intel_iommu *iommu)
+{
+        u32 pmen;
+        unsigned long flags;
+
+        spin_lock_irqsave(&iommu->register_lock, flags);
+        pmen = readl(iommu->reg + DMAR_PMEN_REG);
+        pmen &= ~DMA_PMEN_EPM;
+        writel(pmen, iommu->reg + DMAR_PMEN_REG);
+
+        /* wait for the protected region status bit to clear */
+        IOMMU_WAIT_OP(iommu, DMAR_PMEN_REG,
+                readl, !(pmen & DMA_PMEN_PRS), pmen);
+
+        spin_unlock_irqrestore(&iommu->register_lock, flags);
+}
+
 static int iommu_enable_translation(struct intel_iommu *iommu)
 {
         u32 sts;
@@ -745,7 +762,7 @@ static char *fault_reason_strings[] =
         "non-zero reserved fields in PTE",
         "Unknown"
 };
-#define MAX_FAULT_REASON_IDX    ARRAY_SIZE(fault_reason_strings) - 1
+#define MAX_FAULT_REASON_IDX    (ARRAY_SIZE(fault_reason_strings) - 1)
 
 char *dmar_get_fault_reason(u8 fault_reason)
 {
@@ -1730,6 +1747,8 @@ int __init init_dmars(void)
                 iommu_flush_context_global(iommu, 0);
                 iommu_flush_iotlb_global(iommu, 0);
 
+                iommu_disable_protect_mem_regions(iommu);
+
                 ret = iommu_enable_translation(iommu);
                 if (ret)
                         goto error;
diff --git a/drivers/pci/intel-iommu.h b/drivers/pci/intel-iommu.h
index 0e4862675ad2..07f5f6353bda 100644
--- a/drivers/pci/intel-iommu.h
+++ b/drivers/pci/intel-iommu.h
@@ -140,6 +140,10 @@ static inline void dmar_writeq(void __iomem *addr, u64 val)
 #define DMA_TLB_IH_NONLEAF (((u64)1) << 6)
 #define DMA_TLB_MAX_SIZE (0x3f)
 
+/* PMEN_REG */
+#define DMA_PMEN_EPM (((u32)1)<<31)
+#define DMA_PMEN_PRS (((u32)1)<<0)
+
 /* GCMD_REG */
 #define DMA_GCMD_TE (((u32)1) << 31)
 #define DMA_GCMD_SRTP (((u32)1) << 30)