Re: [PATCH v5 03/10] iommu/mediatek: Modify the usage of mtk_iommu_plat_data structure

[chao hao]

On Tue, 2020-06-30 at 18:56 +0800, Yong Wu wrote:
> 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?

ok, I will try to put it in one line in next version, thanks

> 
> >  	.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.
> 

ok, mtk_iommu_v1.c doesn't use these definitions.
I will move them to mtk_iommu.c in next version, thanks.

> 
> 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
> 
got it , thanks for you advice.


> > +
> >  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];
> >  };
> >  
> 
>