[PATCH] iommu/qcom: add optional clock for TLB invalidate
Shawn Guo
shawn.guo at linaro.org
Sat May 9 13:08:25 UTC 2020
On some SoCs like MSM8939 with A405 adreno, there is a gfx_tbu clock
needs to be on while doing TLB invalidate. Otherwise, TLBSYNC status
will not be correctly reflected, causing the system to go into a bad
state. Add it as an optional clock, so that platforms that have this
clock can pass it over DT.
Signed-off-by: Shawn Guo <shawn.guo at linaro.org>
---
drivers/iommu/qcom_iommu.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/drivers/iommu/qcom_iommu.c b/drivers/iommu/qcom_iommu.c
index 0e2a96467767..2f6c6da7d540 100644
--- a/drivers/iommu/qcom_iommu.c
+++ b/drivers/iommu/qcom_iommu.c
@@ -45,6 +45,7 @@ struct qcom_iommu_dev {
struct device *dev;
struct clk *iface_clk;
struct clk *bus_clk;
+ struct clk *tlb_clk;
void __iomem *local_base;
u32 sec_id;
u8 num_ctxs;
@@ -643,11 +644,20 @@ static int qcom_iommu_enable_clocks(struct qcom_iommu_dev *qcom_iommu)
return ret;
}
+ ret = clk_prepare_enable(qcom_iommu->tlb_clk);
+ if (ret) {
+ dev_err(qcom_iommu->dev, "Couldn't enable tlb_clk\n");
+ clk_disable_unprepare(qcom_iommu->bus_clk);
+ clk_disable_unprepare(qcom_iommu->iface_clk);
+ return ret;
+ }
+
return 0;
}
static void qcom_iommu_disable_clocks(struct qcom_iommu_dev *qcom_iommu)
{
+ clk_disable_unprepare(qcom_iommu->tlb_clk);
clk_disable_unprepare(qcom_iommu->bus_clk);
clk_disable_unprepare(qcom_iommu->iface_clk);
}
@@ -839,6 +849,12 @@ static int qcom_iommu_device_probe(struct platform_device *pdev)
return PTR_ERR(qcom_iommu->bus_clk);
}
+ qcom_iommu->tlb_clk = devm_clk_get(dev, "tlb");
+ if (IS_ERR(qcom_iommu->tlb_clk)) {
+ dev_dbg(dev, "failed to get tlb clock\n");
+ qcom_iommu->tlb_clk = NULL;
+ }
+
if (of_property_read_u32(dev->of_node, "qcom,iommu-secure-id",
&qcom_iommu->sec_id)) {
dev_err(dev, "missing qcom,iommu-secure-id property\n");
--
2.17.1
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