[PATCH v2 09/29] iommu/mediatek: Add tlb_lock in tlb_flush_all

[Yong Wu]

The tlb_flush_all also touches the registers about tlb operations.
Add spinlock in it to protect the tlb registers. If flush_all is called
from tlb_flush_range, then no need this spinlock as tlb_flush_range
already hold the tlb_lock.

Signed-off-by: Yong Wu <yong.wu at mediatek.com>
---
 drivers/iommu/mtk_iommu.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 1e18fff76e61..d64139ab59d0 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -205,15 +205,24 @@ static struct mtk_iommu_domain *to_mtk_domain(struct iommu_domain *dom)
 	return container_of(dom, struct mtk_iommu_domain, domain);
 }
 
-static void mtk_iommu_tlb_flush_all(struct mtk_iommu_data *data)
+static void __mtk_iommu_tlb_flush_all(struct mtk_iommu_data *data)
 {
-	if (pm_runtime_get_if_in_use(data->dev) <= 0)
-		return;
-
 	writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0,
 		       data->base + data->plat_data->inv_sel_reg);
 	writel_relaxed(F_ALL_INVLD, data->base + REG_MMU_INVALIDATE);
 	wmb(); /* Make sure the tlb flush all done */
+}
+
+static void mtk_iommu_tlb_flush_all(struct mtk_iommu_data *data)
+{
+	unsigned long flags;
+
+	if (pm_runtime_get_if_in_use(data->dev) <= 0)
+		return;
+
+	spin_lock_irqsave(&data->tlb_lock, flags);
+	__mtk_iommu_tlb_flush_all(data);
+	spin_unlock_irqrestore(&data->tlb_lock, flags);
 
 	pm_runtime_put(data->dev);
 }
@@ -251,7 +260,7 @@ static void mtk_iommu_tlb_flush_range_sync(unsigned long iova, size_t size,
 		if (ret) {
 			dev_warn(data->dev,
 				 "Partial TLB flush timed out, falling back to full flush\n");
-			mtk_iommu_tlb_flush_all(data);
+			__mtk_iommu_tlb_flush_all(data);
 		}
 		/* Clear the CPE status */
 		writel_relaxed(0, data->base + REG_MMU_CPE_DONE);
-- 
2.18.0