Re: [RFC] hwmon: (fam15h_power) Add bit masking for tdp_limit

[Gi-Oh Kim]

On 27.01.2016 07:45, Huang Rui wrote:
> On Tue, Jan 26, 2016 at 11:57:35AM +0100, Gi-Oh Kim wrote:
> > On 26.01.2016 03:25, Huang Rui wrote:
> > > On Mon, Jan 25, 2016 at 07:41:07PM +0800, Gioh Kim wrote:
> > Thanks for your reply.
> > I'm not completely sure that the reserved bits are always zero.
> > Are they always zero?
> > Or do we need bit-masking like following?
> Reserved bits aren't always zero. But here they are reserved for
> ApmTdpLimit expansion.
>
> Yes, we would better add bit-masking here. :-)
>
> > -------------- 8< -----------------
> > Subject: [PATCH] hwmon: (fam15h_power) Add bit masking for tdp_limit
> >
> > Add bit masking to read ApmTdpLimit precisely
> >
> > Signed-off-by: Gioh Kim <gi-oh.kim@xxxxxxxxxxxxxxxx>
> > ---
> >   drivers/hwmon/fam15h_power.c | 6 +++++-
> >   1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/hwmon/fam15h_power.c b/drivers/hwmon/fam15h_power.c
> > index f77eb97..edbcf6c 100644
> > --- a/drivers/hwmon/fam15h_power.c
> > +++ b/drivers/hwmon/fam15h_power.c
> > @@ -90,7 +90,11 @@ static ssize_t show_power(struct device *dev,
> >       pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
> >                     REG_TDP_LIMIT3, &val);
> >
> > -    tdp_limit = val >> 16;
> > +    if (boot_cpu_data.x86_model >= 0x60)
> > +        tdp_limit = val >> 16;
> You need add CPU family check and a comment to mention bit field
> change. This updates since family 15h and model 60h.
>
> if (boot_cpu_data.x86 == 0x15 && boot_cpu_data.x86_model >= 0x60)

I'm going to send a formal patch.
Thank you.

> Thanks,
> Rui

--
Best regards,
Gi-Oh Kim