Re: [PATCH 2/3] iommu/ipmmu-vmsa: Calculate context registers' offset instead of a macro

["Niklas Söderlund" <niklas.soderlund@ragnatech.se>]

Hi Shimoda-san,

Thanks for your patch.

On 2019-10-09 17:26:48 +0900, Yoshihiro Shimoda wrote:
> Since we will have changed memory mapping of the IPMMU in the future,
> this patch uses ipmmu_features values instead of a macro to
> calculate context registers offset. No behavior change.
> 
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

> ---
>  drivers/iommu/ipmmu-vmsa.c | 27 +++++++++++++++++++--------
>  1 file changed, 19 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
> index dd554c2..76fb250 100644
> --- a/drivers/iommu/ipmmu-vmsa.c
> +++ b/drivers/iommu/ipmmu-vmsa.c
> @@ -50,6 +50,8 @@ struct ipmmu_features {
>  	bool twobit_imttbcr_sl0;
>  	bool reserved_context;
>  	bool cache_snoop;
> +	u32 ctx_offset_base;
> +	u32 ctx_offset_stride;
>  };
>  
>  struct ipmmu_vmsa_device {
> @@ -99,8 +101,6 @@ static struct ipmmu_vmsa_device *to_ipmmu(struct device *dev)
>  
>  #define IM_NS_ALIAS_OFFSET		0x800
>  
> -#define IM_CTX_SIZE			0x40
> -
>  #define IMCTR				0x0000
>  #define IMCTR_TRE			(1 << 17)
>  #define IMCTR_AFE			(1 << 16)
> @@ -253,18 +253,25 @@ static void ipmmu_write(struct ipmmu_vmsa_device *mmu, unsigned int offset,
>  	iowrite32(data, mmu->base + offset);
>  }
>  
> +static u32 ipmmu_ctx_reg(struct ipmmu_vmsa_device *mmu, unsigned int context_id,
> +			 unsigned int reg)
> +{
> +	return mmu->features->ctx_offset_base +
> +	       context_id * mmu->features->ctx_offset_stride + reg;
> +}
> +
>  static u32 ipmmu_ctx_read_root(struct ipmmu_vmsa_domain *domain,
>  			       unsigned int reg)
>  {
>  	return ipmmu_read(domain->mmu->root,
> -			  domain->context_id * IM_CTX_SIZE + reg);
> +			  ipmmu_ctx_reg(domain->mmu, domain->context_id, reg));
>  }
>  
>  static void ipmmu_ctx_write_root(struct ipmmu_vmsa_domain *domain,
>  				 unsigned int reg, u32 data)
>  {
>  	ipmmu_write(domain->mmu->root,
> -		    domain->context_id * IM_CTX_SIZE + reg, data);
> +		    ipmmu_ctx_reg(domain->mmu, domain->context_id, reg), data);
>  }
>  
>  static void ipmmu_ctx_write_all(struct ipmmu_vmsa_domain *domain,
> @@ -272,10 +279,10 @@ static void ipmmu_ctx_write_all(struct ipmmu_vmsa_domain *domain,
>  {
>  	if (domain->mmu != domain->mmu->root)
>  		ipmmu_write(domain->mmu,
> -			    domain->context_id * IM_CTX_SIZE + reg, data);
> +			    ipmmu_ctx_reg(domain->mmu, domain->context_id, reg),
> +			    data);
>  
> -	ipmmu_write(domain->mmu->root,
> -		    domain->context_id * IM_CTX_SIZE + reg, data);
> +	ipmmu_ctx_write_root(domain, reg, data);
>  }
>  
>  /* -----------------------------------------------------------------------------
> @@ -974,7 +981,7 @@ static void ipmmu_device_reset(struct ipmmu_vmsa_device *mmu)
>  
>  	/* Disable all contexts. */
>  	for (i = 0; i < mmu->num_ctx; ++i)
> -		ipmmu_write(mmu, i * IM_CTX_SIZE + IMCTR, 0);
> +		ipmmu_write(mmu, ipmmu_ctx_reg(mmu, i, IMCTR), 0);
>  }
>  
>  static const struct ipmmu_features ipmmu_features_default = {
> @@ -986,6 +993,8 @@ static const struct ipmmu_features ipmmu_features_default = {
>  	.twobit_imttbcr_sl0 = false,
>  	.reserved_context = false,
>  	.cache_snoop = true,
> +	.ctx_offset_base = 0,
> +	.ctx_offset_stride = 0x40,
>  };
>  
>  static const struct ipmmu_features ipmmu_features_rcar_gen3 = {
> @@ -997,6 +1006,8 @@ static const struct ipmmu_features ipmmu_features_rcar_gen3 = {
>  	.twobit_imttbcr_sl0 = true,
>  	.reserved_context = true,
>  	.cache_snoop = false,
> +	.ctx_offset_base = 0,
> +	.ctx_offset_stride = 0x40,
>  };
>  
>  static const struct of_device_id ipmmu_of_ids[] = {
> -- 
> 2.7.4
> 

-- 
Regards,
Niklas Söderlund