[PATCHv2 3/6] iommu/intel: Introduce clear_primary_faults() helper

[Dmitry Safonov <dima@arista.com>]

To my mind it's a bit more readable - and I will re-use it in the next
patch.

Signed-off-by: Dmitry Safonov <dima@arista.com>
---
 drivers/iommu/dmar.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index accf58388bdb..33fb4244e438 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -1611,6 +1611,15 @@ static int dmar_fault_do_one(struct intel_iommu *iommu, int type,
 	return 0;
 }
 
+static void clear_primary_faults(struct intel_iommu *iommu)
+{
+	volatile void __iomem *fsts = iommu->reg + DMAR_FSTS_REG;
+
+	assert_raw_spin_locked(&iommu->register_lock);
+
+	writel(DMA_FSTS_PFO | DMA_FSTS_PPF | DMA_FSTS_PRO, fsts);
+}
+
 #define PRIMARY_FAULT_REG_LEN (16)
 irqreturn_t dmar_fault(int irq, void *dev_id)
 {
@@ -1679,8 +1688,7 @@ irqreturn_t dmar_fault(int irq, void *dev_id)
 		raw_spin_lock_irqsave(&iommu->register_lock, flag);
 	}
 
-	writel(DMA_FSTS_PFO | DMA_FSTS_PPF | DMA_FSTS_PRO,
-	       iommu->reg + DMAR_FSTS_REG);
+	clear_primary_faults(iommu);
 
 unlock_exit:
 	raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
-- 
2.13.6