Re: [PATCH v4 08/14] iommu/amd: Consolidate feature detection and reporting logic

[Jason Gunthorpe <jgg@ziepe.ca>]

On Tue, Aug 15, 2023 at 10:21:56AM +0000, Vasant Hegde wrote:

> diff --git a/drivers/iommu/amd/amd_iommu.h b/drivers/iommu/amd/amd_iommu.h
> index 6bf55de9fbeb..242e25ba2f93 100644
> --- a/drivers/iommu/amd/amd_iommu.h
> +++ b/drivers/iommu/amd/amd_iommu.h
> @@ -90,9 +90,19 @@ static inline bool is_rd890_iommu(struct pci_dev *pdev)
>  	       (pdev->device == PCI_DEVICE_ID_RD890_IOMMU);
>  }
>  
> -static inline bool iommu_feature(struct amd_iommu *iommu, u64 mask)
> +static inline bool check_feature(u64 mask)
>  {
> -	return !!(iommu->features & mask);
> +	return !!(amd_iommu_efr & mask);
> +}
> +
> +static inline bool check_feature2(u64 mask)
> +{
> +	return !!(amd_iommu_efr2 & mask);
> +}

You don't need the !! when returning a bool

> @@ -2012,8 +2002,8 @@ static ssize_t amd_iommu_show_features(struct device *dev,
>  				       struct device_attribute *attr,
>  				       char *buf)
>  {
> -	struct amd_iommu *iommu = dev_to_amd_iommu(dev);
> -	return sysfs_emit(buf, "%llx:%llx\n", iommu->features2, iommu->features);
> +	return sysfs_emit(buf, "EFR:%llx, EFR2:%llx\n",
> +			  amd_iommu_efr, amd_iommu_efr2);
>  }
>  static DEVICE_ATTR(features, S_IRUGO, amd_iommu_show_features, NULL);

Can't do this, sysfs is ABI (and it should have not have returned two
values in the first place, Greg would reject it)

But the rest looks OK

Jason