[PATCH 09/24] iommu/mediatek: Always pm_runtime_get while tlb flush

Yong Wu yong.wu at mediatek.com
Tue Jun 29 19:34:49 PDT 2021


In previous soc, some SoC don't have PM. Only mt8192 has power-domain,
and it's display's power-domain which nearly always is enabled.

When there are 2 M4U HW, it may has problem.
In this function, we get the pm_status via the m4u dev, but it don't
reflect the real power-domain status of the HW since there may be other
HW also use that power-domain.

Currently We can not get the real power-domain status, thus I always
pm_runtime_get here.

This pach is only a preparing patch for 2 HW sharing pgtable in different
power-domains, like mt8195 case. thus, no need fix tags here.

this patch may drop the performance, we expect the user could
pm_runtime_get_sync before dma_alloc_attrs.

Signed-off-by: Yong Wu <yong.wu at mediatek.com>
---
 drivers/iommu/mtk_iommu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index ed3455b5cef0..fcf70787d3d1 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -231,7 +231,7 @@ static void mtk_iommu_tlb_flush_range_sync(unsigned long iova, size_t size,
 
 	for_each_m4u(data, head) {
 		if (has_pm) {
-			if (pm_runtime_get_if_in_use(data->dev) <= 0)
+			if (pm_runtime_resume_and_get(data->dev) < 0)
 				continue;
 		}
 
-- 
2.18.0


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