1 files changed, 11 insertions, 8 deletions

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 22d7d050905d..de39e1f2ede5 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -101,16 +101,13 @@ static int iommu_queue_command(struct amd_iommu *iommu, struct iommu_cmd *cmd)
  */
 static int iommu_completion_wait(struct amd_iommu *iommu)
 {
-        int ret;
+        int ret, ready = 0;
+        unsigned status = 0;
         struct iommu_cmd cmd;
-        volatile u64 ready = 0;
-        unsigned long ready_phys = virt_to_phys(&ready);
         unsigned long i = 0;
 
         memset(&cmd, 0, sizeof(cmd));
-        cmd.data[0] = LOW_U32(ready_phys) | CMD_COMPL_WAIT_STORE_MASK;
-        cmd.data[1] = upper_32_bits(ready_phys);
-        cmd.data[2] = 1; /* value written to 'ready' */
+        cmd.data[0] = CMD_COMPL_WAIT_INT_MASK;
         CMD_SET_TYPE(&cmd, CMD_COMPL_WAIT);
 
         iommu->need_sync = 0;
@@ -122,9 +119,15 @@ static int iommu_completion_wait(struct amd_iommu *iommu)
 
         while (!ready && (i < EXIT_LOOP_COUNT)) {
                 ++i;
-                cpu_relax();
+                /* wait for the bit to become one */
+                status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET);
+                ready = status & MMIO_STATUS_COM_WAIT_INT_MASK;
         }
 
+        /* set bit back to zero */
+        status &= ~MMIO_STATUS_COM_WAIT_INT_MASK;
+        writel(status, iommu->mmio_base + MMIO_STATUS_OFFSET);
+
         if (unlikely((i == EXIT_LOOP_COUNT) && printk_ratelimit()))
                 printk(KERN_WARNING "AMD IOMMU: Completion wait loop failed\n");
 
@@ -161,7 +164,7 @@ static int iommu_queue_inv_iommu_pages(struct amd_iommu *iommu,
         address &= PAGE_MASK;
         CMD_SET_TYPE(&cmd, CMD_INV_IOMMU_PAGES);
         cmd.data[1] |= domid;
-        cmd.data[2] = LOW_U32(address);
+        cmd.data[2] = lower_32_bits(address);
         cmd.data[3] = upper_32_bits(address);
         if (s) /* size bit - we flush more than one 4kb page */
                 cmd.data[2] |= CMD_INV_IOMMU_PAGES_SIZE_MASK;