Re: [V2 4/6] platform/x86: Add Intel Software Defined Silicon driver

David E. Box
2021-12-08T10:42:45Z

On Wed, 2021-12-08 at 09:14 +0200, Leon Romanovsky wrote:
> On Tue, Dec 07, 2021 at 09:14:46AM -0800, David E. Box wrote:
> > Intel Software Defined Silicon (SDSi) is a post manufacturing mechanism for
> > activating additional silicon features. Features are enabled through a
> > license activation process. The SDSi driver provides a per socket, sysfs
> > attribute interface for applications to perform 3 main provisioning
> > functions:
> >
> > 1. Provision an Authentication Key Certificate (AKC), a key written to
> > internal NVRAM that is used to authenticate a capability specific
> > activation payload.
> >
> > 2. Provision a Capability Activation Payload (CAP), a token authenticated
> > using the AKC and applied to the CPU configuration to activate a new
> > feature.
> >
> > 3. Read the SDSi State Certificate, containing the CPU configuration
> > state.
> >
> > The operations perform function specific mailbox commands that forward the
> > requests to SDSi hardware to perform authentication of the payloads and
> > enable the silicon configuration (to be made available after power
> > cycling).
> >
> > The SDSi device itself is enumerated as an auxiliary device from the
> > intel_vsec driver and as such has a build dependency on CONFIG_INTEL_VSEC.
> >
> > Link: https://github.com/intel/intel-sdsi
> > Signed-off-by: David E. Box <david.e.box@linux.intel.com>
> > Reviewed-by: Mark Gross <markgross@kernel.org>
> > ---
> > V2
> > - Use sysfs_emit() in guid_show()
> > - Fix language in ABI, suggested by Bjorn
> > - Fix wrong directory name in ABI doc
>
> <...>
>
> > @@ -0,0 +1,77 @@
> > +What: /sys/bus/auxiliary/devices/intel_vsec.sdsi.X
>
> <...>
>
> > +static const struct auxiliary_device_id sdsi_aux_id_table[] = {
> > + { .name = "intel_vsec.sdsi" },
>
> Are you sure that this sysfs is correct?
>
> Auxiliary bus set device name as a combination of module name plus suffix.
>
> 172 int __auxiliary_device_add(struct auxiliary_device *auxdev, const char
> *modname)
> 173 {
> 174 struct device *dev = &auxdev->dev;
> 175 int ret;
> ....
> 181
> 182 ret = dev_set_name(dev, "%s.%s.%d", modname, auxdev->name,
> auxdev->id);
>
> Thanks

Yes. 'intel_vsec' is the module name, 'sdsi' is the suffix, and 'X' is meant to
indicate the unique id. Will change to '*' instead of 'X'.

Thanks

David