Re: [PATCH v3] PCI/DOE: Expose the DOE protocols via sysfs

[Randy Dunlap <rdunlap@infradead.org>]

Hi--

On 8/9/23 16:28, Alistair Francis wrote:
> The PCIe 6 specification added support for the Data Object Exchange (DOE).
> When DOE is supported the Discovery Data Object Protocol must be
> implemented. The protocol allows a requester to obtain information about
> the other DOE protocols supported by the device.
> 
> The kernel is already querying the DOE protocols supported and cacheing
> the values. This patch exposes the values via sysfs. This will allow
> userspace to determine which DOE protocols are supported by the PCIe
> device.
> 
> By exposing the information to userspace tools like lspci can relay the
> information to users. By listing all of the supported protocols we can
> allow userspace to parse and support the list, which might include
> vendor specific protocols as well as yet to be supported protocols.
> 
> Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
> ---
> v3:
>  - Expose each DOE feature as a separate file
> 
>  Documentation/ABI/testing/sysfs-bus-pci |  10 +++
>  drivers/pci/doe.c                       | 107 ++++++++++++++++++++++++
>  drivers/pci/pci-sysfs.c                 |   7 ++
>  include/linux/pci-doe.h                 |   1 +
>  4 files changed, 125 insertions(+)
> 
> diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
> index ecf47559f495..e754b8efdb69 100644
> --- a/Documentation/ABI/testing/sysfs-bus-pci
> +++ b/Documentation/ABI/testing/sysfs-bus-pci
> @@ -500,3 +500,13 @@ Description:
>  		console drivers from the device.  Raw users of pci-sysfs
>  		resourceN attributes must be terminated prior to resizing.
>  		Success of the resizing operation is not guaranteed.
> +
> +What:		/sys/bus/pci/devices/.../doe_proto

Should this be                                   doe_protos
? like this:
+	.name	= "doe_protos",


> +Date:		July 2023
> +Contact:	Linux PCI developers <linux-pci@vger.kernel.org>
> +Description:
> +		This diectory contains a list of the supported Data Object Exchange (DOE)

		     directory

> +		features. Each feature is a single file.

		The feature values are in the file name; the files have no contents.
?

> +		The value comes from the device and specifies the vendor and
> +		data object type supported. The lower byte is the data object type and the next
> +		two bytes are the vendor ID.

-- 
~Randy