On 10/06/2019 14:17, Yong Wu wrote: > In some SoCs, M4U doesn't have its "bclk", it will use the EMI > clock instead which has always been enabled when entering kernel. > > Currently mt2712 and mt8173 have this bclk while mt8183 doesn't. > > This also is a preparing patch for mt8183. > > Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx> > Reviewed-by: Evan Green <evgreen@xxxxxxxxxxxx> Reviewed-by: Matthias Brugger <matthias.bgg@xxxxxxxxx> > --- > 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 aff5004..264dda4 100644 > --- a/drivers/iommu/mtk_iommu.c > +++ b/drivers/iommu/mtk_iommu.c > @@ -611,9 +611,11 @@ 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); > @@ -741,11 +743,13 @@ 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 d7a001a..63e235e 100644 > --- a/drivers/iommu/mtk_iommu.h > +++ b/drivers/iommu/mtk_iommu.h > @@ -43,6 +43,9 @@ 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; >