Re: [PATCH v3] soc: qcom: Add SoC info driver

From: Bjorn Andersson
Date: Tue Nov 15 2016 - 00:28:01 EST


On Mon 14 Nov 06:30 PST 2016, Imran Khan wrote:

> On 11/8/2016 1:05 AM, Bjorn Andersson wrote:
> > On Mon 07 Nov 06:35 PST 2016, Imran Khan wrote:
> >
> >
> >
> > [..]
> >
> >>>> +static void socinfo_populate(struct soc_device_attribute *soc_dev_attr)
> >>>> +{
> >>>> + u32 soc_version = socinfo_get_version();
> >>>> +
> >>>> + soc_dev_attr->soc_id = kasprintf(GFP_KERNEL, "%d", socinfo_get_id());
> >>>
> >>> I believe soc_id is supposed to be a human readable name; e.g. "MSM8996"
> >>> not "246".
> >>>
> >>
> >> I am not sure about this. I see other vendors also exposing soc_id as numeric value
> >> and machine is perhaps used for a human readable name. Please let me if I
> >> am getting something wrong here.
> >>
> >
> > I'm slightly confused to what these various properties are supposed to
> > contain, according to Documentation/ABI/testing/sysfs-devices-soc soc_id
> > should contain the SoC serial number, while most implementations does
> > like you and put something telling which SoC it is.
> >
> > 246 is however not a useful number, as everyone reading it - be it human
> > or computer - will have to carry the translation table to figure out
> > what it actually says.
> >
>
> Yeah. I agree on this point. I was just following the lead of other SoCs here.
> Just worried if having a string here breaks the convention. At least having
> a numeric number is more in line with the documentation which expects a
> serial number. May be here by serial number the documentation means numeric
> id itself. Can someone please provide some feedback?
>

Yeah, the more i look at this the more puzzled I become about what
should go where.

> >>>> + soc_dev_attr->family = "Snapdragon";
> >
> > I think family should be e.g. "MSM8996" and then machine should be e.g.
> > "MSM8996AU".
> >
>
> I think here family should be Snapdragon.The following site also mentions
> the SoCs as Snapdragon family of processors.
>
> https://www.qualcomm.com/products/snapdragon/processors/comparison
>
> Could you please confirm if it's okay?
>

In our previous technical discussions regarding Qualcomm platforms the
possible values for "family" would be U, A and B (maybe something new
these days?).

But I don't think we gain anything from having the kernel tell us this.

So I'm fine with you reporting "Snapdragon" as family and I guess
machine would then get e.g. "APQ8096". I don't know what to put in
soc_id.

I think this would be sufficient for user space's needs.

Regards,
Bjorn