On Thu, 14 Apr 2022, Oleksandr Tyshchenko wrote:
> From: Oleksandr Tyshchenko <[email protected]>
>
> Introduce Xen specific binding for the virtio-mmio device to be used
> by Xen virtio support driver in a subsequent commit.
>
> This binding specifies the ID of Xen domain where the corresponding
> device (backend) resides. This is needed for the option to restrict
> memory access using Xen grant mappings to work.
>
> Signed-off-by: Oleksandr Tyshchenko <[email protected]>
> ---
> .../devicetree/bindings/virtio/xen,dev-domid.yaml | 39 ++++++++++++++++++++++
> 1 file changed, 39 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/virtio/xen,dev-domid.yaml
>
> diff --git a/Documentation/devicetree/bindings/virtio/xen,dev-domid.yaml b/Documentation/devicetree/bindings/virtio/xen,dev-domid.yaml
> new file mode 100644
> index 00000000..78be993
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/virtio/xen,dev-domid.yaml
> @@ -0,0 +1,39 @@
> +# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/virtio/xen,dev-domid.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Xen specific binding for the virtio device
> +
> +maintainers:
> + - Oleksandr Tyshchenko <[email protected]>
> +
> +select: true
> +
> +description:
> + This binding specifies the ID of Xen domain where the corresponding device
> + (backend) resides. This is needed for the option to restrict memory access
> + using Xen grant mappings to work.
> +
> + Note that current and generic "iommus" bindings are mutually exclusive, since
> + the restricted memory access model on Xen behaves as a kind of software IOMMU.
I don't think that this last statement is necessary or fully accurate, so
I would remove it. Other than that, this looks good to me.
> +properties:
> + xen,dev-domid:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description:
> + Should contain the ID of device's domain.
Maybe better as:
"The domid (domain ID) of the domain where the device (backend) is running"
> +additionalProperties: true
> +
> +examples:
> + - |
> + virtio_block@3000 {
> + compatible = "virtio,mmio";
> + reg = <0x3000 0x100>;
> + interrupts = <41>;
> +
> + /* The device is located in Xen domain with ID 1 */
> + xen,dev-domid = <1>;
> + };
> --
> 2.7.4
>
On 16.04.22 01:01, Stefano Stabellini wrote:
Hello Stefano
> On Thu, 14 Apr 2022, Oleksandr Tyshchenko wrote:
>> From: Oleksandr Tyshchenko <[email protected]>
>>
>> Introduce Xen specific binding for the virtio-mmio device to be used
>> by Xen virtio support driver in a subsequent commit.
>>
>> This binding specifies the ID of Xen domain where the corresponding
>> device (backend) resides. This is needed for the option to restrict
>> memory access using Xen grant mappings to work.
>>
>> Signed-off-by: Oleksandr Tyshchenko <[email protected]>
>> ---
>> .../devicetree/bindings/virtio/xen,dev-domid.yaml | 39 ++++++++++++++++++++++
>> 1 file changed, 39 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/virtio/xen,dev-domid.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/virtio/xen,dev-domid.yaml b/Documentation/devicetree/bindings/virtio/xen,dev-domid.yaml
>> new file mode 100644
>> index 00000000..78be993
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/virtio/xen,dev-domid.yaml
>> @@ -0,0 +1,39 @@
>> +# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/virtio/xen,dev-domid.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Xen specific binding for the virtio device
>> +
>> +maintainers:
>> + - Oleksandr Tyshchenko <[email protected]>
>> +
>> +select: true
>> +
>> +description:
>> + This binding specifies the ID of Xen domain where the corresponding device
>> + (backend) resides. This is needed for the option to restrict memory access
>> + using Xen grant mappings to work.
>> +
>> + Note that current and generic "iommus" bindings are mutually exclusive, since
>> + the restricted memory access model on Xen behaves as a kind of software IOMMU.
> I don't think that this last statement is necessary or fully accurate, so
> I would remove it.
ok, will remove
> Other than that, this looks good to me.
thank you
>
>
>> +properties:
>> + xen,dev-domid:
>> + $ref: /schemas/types.yaml#/definitions/uint32
>> + description:
>> + Should contain the ID of device's domain.
> Maybe better as:
> "The domid (domain ID) of the domain where the device (backend) is running"
ok, will change
>
>
>
>> +additionalProperties: true
>> +
>> +examples:
>> + - |
>> + virtio_block@3000 {
>> + compatible = "virtio,mmio";
>> + reg = <0x3000 0x100>;
>> + interrupts = <41>;
>> +
>> + /* The device is located in Xen domain with ID 1 */
>> + xen,dev-domid = <1>;
>> + };
>> --
>> 2.7.4
>>
--
Regards,
Oleksandr Tyshchenko