Hi Chao, This is also ok for me. Only two format nitpick. On Mon, 2020-06-29 at 15:13 +0800, Chao Hao wrote: > Given the fact that we are adding more and more plat_data bool values, > it would make sense to use a u32 flags register and add the appropriate > macro definitions to set and check for a flag present. > No functional change. > > Suggested-by: Matthias Brugger <matthias.bgg@xxxxxxxxx> > Signed-off-by: Chao Hao <chao.hao@xxxxxxxxxxxx> > --- [snip] > static const struct mtk_iommu_plat_data mt2712_data = { > .m4u_plat = M4U_MT2712, > - .has_4gb_mode = true, > - .has_bclk = true, > - .has_vld_pa_rng = true, > + .flags = HAS_4GB_MODE | > + HAS_BCLK | > + HAS_VLD_PA_RNG, short enough. we can put it in one line? > .larbid_remap = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}, > }; > > static const struct mtk_iommu_plat_data mt8173_data = { > .m4u_plat = M4U_MT8173, > - .has_4gb_mode = true, > - .has_bclk = true, > - .reset_axi = true, > + .flags = HAS_4GB_MODE | > + HAS_BCLK | > + RESET_AXI, > .larbid_remap = {0, 1, 2, 3, 4, 5}, /* Linear mapping. */ > }; > > static const struct mtk_iommu_plat_data mt8183_data = { > .m4u_plat = M4U_MT8183, > - .reset_axi = true, > + .flags = RESET_AXI, > .larbid_remap = {0, 4, 5, 6, 7, 2, 3, 1}, > }; > > diff --git a/drivers/iommu/mtk_iommu.h b/drivers/iommu/mtk_iommu.h > index 1b6ea839b92c..7cc39f729263 100644 > --- a/drivers/iommu/mtk_iommu.h > +++ b/drivers/iommu/mtk_iommu.h > @@ -17,6 +17,15 @@ > #include <linux/spinlock.h> > #include <soc/mediatek/smi.h> > > +#define HAS_4GB_MODE BIT(0) > +/* HW will use the EMI clock if there isn't the "bclk". */ > +#define HAS_BCLK BIT(1) > +#define HAS_VLD_PA_RNG BIT(2) > +#define RESET_AXI BIT(3) > + > +#define MTK_IOMMU_HAS_FLAG(pdata, _x) \ > + ((((pdata)->flags) & (_x)) == (_x)) If these definitions are not used in mtk_iommu_v1.c(also no this plan), then we can put them in the mtk_iommu.c. BTW, the patch title "modify the usage of mtk_iommu_plat_data structure" isn't so clear, we could write what the detailed modification is. something like: iommu/mediatek: Use a u32 flags to describe different HW features > + > struct mtk_iommu_suspend_reg { > u32 misc_ctrl; > u32 dcm_dis; > @@ -36,12 +45,7 @@ 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; > - bool has_vld_pa_rng; > - bool reset_axi; > + u32 flags; > unsigned char larbid_remap[MTK_LARB_NR_MAX]; > }; >