[PATCH v5 07/20] iommu/mediatek: Add bclk can be supported optionally

Yong Wu
2019-01-01T03:59:09Z

In some SoCs, M4U doesn't have its "bclk", it will use the EMI
clock instead which has always been enabled when entering kernel.

This also is a preparing patch for mt8183.

Signed-off-by: Yong Wu <yong.wu@mediatek.com>
---
drivers/iommu/mtk_iommu.c | 10 +++++++---
drivers/iommu/mtk_iommu.h | 3 +++
2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index ae1aa5a..847082c 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -613,9 +613,11 @@ static int mtk_iommu_probe(struct platform_device *pdev)
if (data->irq < 0)
return data->irq;

- data->bclk = devm_clk_get(dev, "bclk");
- if (IS_ERR(data->bclk))
- return PTR_ERR(data->bclk);
+ if (data->plat_data->has_bclk) {
+ data->bclk = devm_clk_get(dev, "bclk");
+ if (IS_ERR(data->bclk))
+ return PTR_ERR(data->bclk);
+ }

larb_nr = of_count_phandle_with_args(dev->of_node,
"mediatek,larbs", NULL);
@@ -739,11 +741,13 @@ static int __maybe_unused mtk_iommu_resume(struct device *dev)
static const struct mtk_iommu_plat_data mt2712_data = {
.m4u_plat = M4U_MT2712,
.has_4gb_mode = true,
+ .has_bclk = true,
};

static const struct mtk_iommu_plat_data mt8173_data = {
.m4u_plat = M4U_MT8173,
.has_4gb_mode = true,
+ .has_bclk = true,
};

static const struct of_device_id mtk_iommu_of_ids[] = {
diff --git a/drivers/iommu/mtk_iommu.h b/drivers/iommu/mtk_iommu.h
index 5890e55..b8749ac 100644
--- a/drivers/iommu/mtk_iommu.h
+++ b/drivers/iommu/mtk_iommu.h
@@ -44,6 +44,9 @@ enum mtk_iommu_plat {
struct mtk_iommu_plat_data {
enum mtk_iommu_plat m4u_plat;
bool has_4gb_mode;
+
+ /* HW will use the EMI clock if there isn't the "bclk". */
+ bool has_bclk;
};

struct mtk_iommu_domain;
--
1.9.1