iommu/vt-d: dmar_fault should only clear PPF/PFO field.

When there is a dmar irq, dmar_fault is called and all of the fields
in FSTS are cleared. But ICE/IQE/ITE should not be cleared here,
they need to be processed and cleared in function qi_check_fault.

[Minor cleanup by Joerg Roedel]

Signed-off-by: Li, Zhen-Hua <zhen-hual@hp.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>

1 files changed, 7 insertions, 5 deletions

diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index e5cdaf87822c..9f8aa07360ba 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -1204,7 +1204,7 @@ irqreturn_t dmar_fault(int irq, void *dev_id)
 
         /* TBD: ignore advanced fault log currently */
         if (!(fault_status & DMA_FSTS_PPF))
-                goto clear_rest;
+                goto unlock_exit;
 
         fault_index = dma_fsts_fault_record_index(fault_status);
         reg = cap_fault_reg_offset(iommu->cap);
@@ -1245,11 +1245,10 @@ irqreturn_t dmar_fault(int irq, void *dev_id)
                         fault_index = 0;
                 raw_spin_lock_irqsave(&iommu->register_lock, flag);
         }
-clear_rest:
-        /* clear all the other faults */
-        fault_status = readl(iommu->reg + DMAR_FSTS_REG);
-        writel(fault_status, iommu->reg + DMAR_FSTS_REG);
 
+        writel(DMA_FSTS_PFO | DMA_FSTS_PPF, iommu->reg + DMAR_FSTS_REG);
+
+unlock_exit:
         raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
         return IRQ_HANDLED;
 }
@@ -1297,6 +1296,7 @@ int __init enable_drhd_fault_handling(void)
         for_each_drhd_unit(drhd) {
                 int ret;
                 struct intel_iommu *iommu = drhd->iommu;
+                u32 fault_status;
                 ret = dmar_set_interrupt(iommu);
 
                 if (ret) {
@@ -1309,6 +1309,8 @@ int __init enable_drhd_fault_handling(void)
                  * Clear any previous faults.
                  */
                 dmar_fault(iommu->irq, iommu);
+                fault_status = readl(iommu->reg + DMAR_FSTS_REG);
+                writel(fault_status, iommu->reg + DMAR_FSTS_REG);
         }
 
         return 0;