To simplify the code, Remove the power status checking in the
tlb_flush_all, remove this:
if (pm_runtime_get_if_in_use(data->dev) <= 0)
continue;
After this patch, the mtk_iommu_tlb_flush_all will be called from
a) isr
b) pm runtime resume callback
c) tlb flush range fail case
d) iommu_create_device_direct_mappings
-> iommu_flush_iotlb_all
In first three cases, the power and clock always are enabled; d) is direct
mapping, the tlb flush is unnecessay since we already have tlb_flush_all
in the pm_runtime_resume callback. When the iommu's power status is
changed to active, the tlb always is clean.
In addition, there still are 2 reasons that don't add PM status checking
in the tlb flush all:
a) Write tlb flush all register also is ok even though the HW has no
power and clocks. Write ignore.
b) pm_runtime_get_if_in_use(m4udev) is 0 when the tlb_flush_all
is called frm pm_runtime_resume cb. From this point, we can not add
this code above in this tlb_flush_all.
Signed-off-by: Yong Wu <yong...@mediatek.com>
---
drivers/iommu/mtk_iommu.c | 20 +++++++-------------
1 file changed, 7 insertions(+), 13 deletions(-)
diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index e9e94944ed91..4a33b6c6b1db 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -204,10 +204,14 @@ 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_do_flush_all(struct mtk_iommu_data *data)
+static void mtk_iommu_tlb_flush_all(struct mtk_iommu_data *data)
{
unsigned long flags;
+ /*
+ * No need get power status since the HW PM status nearly is active
+ * when entering here.
+ */
spin_lock_irqsave(&data->tlb_lock, flags);
writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0,
data->base + data->plat_data->inv_sel_reg);
@@ -216,16 +220,6 @@ static void mtk_iommu_tlb_do_flush_all(struct
mtk_iommu_data *data)
spin_unlock_irqrestore(&data->tlb_lock, flags);
}
-static void mtk_iommu_tlb_flush_all(struct mtk_iommu_data *data)
-{
- if (pm_runtime_get_if_in_use(data->dev) <= 0)
- return;
-
- mtk_iommu_tlb_do_flush_all(data);
-
- pm_runtime_put(data->dev);
-}
-
static void mtk_iommu_tlb_flush_range_sync(unsigned long iova, size_t size,
struct mtk_iommu_data *data)
{
@@ -263,7 +257,7 @@ 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_do_flush_all(data);
+ mtk_iommu_tlb_flush_all(data);
}
if (has_pm)
@@ -993,7 +987,7 @@ static int __maybe_unused mtk_iommu_runtime_resume(struct
device *dev)
*
* Thus, Make sure the tlb always is clean after each PM resume.
*/
- mtk_iommu_tlb_do_flush_all(data);
+ mtk_iommu_tlb_flush_all(data);
/*
* Uppon first resume, only enable the clk and return, since the values
of the
--
2.18.0
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