Re: [PATCH v3 04/13] ACPI/IORT: Support PASID for platform devices

[Auger Eric <eric.auger@redhat.com>]

Hi Jean,
On 12/9/19 7:05 PM, Jean-Philippe Brucker wrote:
> Named component nodes in the IORT tables describe the number of
> Substream ID bits (aka. PASID) supported by the device. Propagate this
> value to the fwspec structure in order to enable PASID for platform
> devices.
> 
> Acked-by: Hanjun Guo <guohanjun@huawei.com>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>

Thanks

Eric

> ---
>  drivers/acpi/arm64/iort.c | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> index 33f71983e001..39f389214ecf 100644
> --- a/drivers/acpi/arm64/iort.c
> +++ b/drivers/acpi/arm64/iort.c
> @@ -11,6 +11,7 @@
>  #define pr_fmt(fmt)	"ACPI: IORT: " fmt
>  
>  #include <linux/acpi_iort.h>
> +#include <linux/bitfield.h>>  #include <linux/iommu.h>
>  #include <linux/kernel.h>
>  #include <linux/list.h>
> @@ -924,6 +925,20 @@ static int iort_pci_iommu_init(struct pci_dev *pdev, u16 alias, void *data)
>  	return iort_iommu_xlate(info->dev, parent, streamid);
>  }
>  
> +static void iort_named_component_init(struct device *dev,
> +				      struct acpi_iort_node *node)
> +{
> +	struct acpi_iort_named_component *nc;
> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> +
> +	if (!fwspec)
> +		return;
> +
> +	nc = (struct acpi_iort_named_component *)node->node_data;
> +	fwspec->num_pasid_bits = FIELD_GET(ACPI_IORT_NC_PASID_BITS,
> +					   nc->node_flags);
> +}
> +
>  /**
>   * iort_iommu_configure - Set-up IOMMU configuration for a device.
>   *
> @@ -978,6 +993,9 @@ const struct iommu_ops *iort_iommu_configure(struct device *dev)
>  			if (parent)
>  				err = iort_iommu_xlate(dev, parent, streamid);
>  		} while (parent && !err);
> +
> +		if (!err)
> +			iort_named_component_init(dev, node);
>  	}
>  
>  	/*
>