Messages in this thread | | | From | Len Brown <> | Date | Fri, 12 Mar 2021 17:15:51 -0500 | Subject | Re: [PATCH] tools/power/x86/turbostat: Fix TCC offset bit mask |
| |
Doug, The offset works for control.
However, it is erroneous to use it for reporting of the actual temperature, like I did in turbostat. Thus, I'm going to revert the patch that added it's use in turbostat for the Temperature column.
thanks, -Len
On Fri, Mar 12, 2021 at 1:26 AM Doug Smythies <dsmythies@telus.net> wrote: > > Hi Len, > > > thank you for your reply. > > On Thu, Mar 11, 2021 at 3:19 PM Len Brown <lenb@kernel.org> wrote: > > > > Thanks for the close read, Doug. > > > > This field size actually varies from system to system, > > but the reality is that the offset is never that big, and so the > > smaller mask is sufficient. > > Disagree. > > I want to use an offset of 26. > > > Finally, this may all be moot, because there is discussion that using > > the offset this way is simply erroneous. > > Disagree. > It works great. > As far as I know/recall I was the only person that responded to Rui's thread > "thermal/intel: introduce tcc cooling driver" [1] > And, I spent quite a bit of time doing so. > However, I agree the response seems different between the two systems > under test, Rui's and mine. > > [1] https://marc.info/?l=linux-pm&m=161070345329806&w=2 > > > stay tuned. > > O.K. > > ... Doug > > > > -Len > > > > > > On Sat, Jan 16, 2021 at 12:07 PM Doug Smythies <doug.smythies@gmail.com> wrote: > > > > > > The TCC offset mask is incorrect, resulting in > > > incorrect target temperature calculations, if > > > the offset is big enough to exceed the mask size. > > > > > > Signed-off-by: Doug Smythies <dsmythies@telus.net> > > > --- > > > tools/power/x86/turbostat/turbostat.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c > > > index 389ea5209a83..d7acdd4d16c4 100644 > > > --- a/tools/power/x86/turbostat/turbostat.c > > > +++ b/tools/power/x86/turbostat/turbostat.c > > > @@ -4823,7 +4823,7 @@ int read_tcc_activation_temp() > > > > > > target_c = (msr >> 16) & 0xFF; > > > > > > - offset_c = (msr >> 24) & 0xF; > > > + offset_c = (msr >> 24) & 0x3F; > > > > > > tcc = target_c - offset_c; > > > > > > -- > > > 2.25.1 > > > > > > > > > -- > > Len Brown, Intel Open Source Technology Center
-- Len Brown, Intel Open Source Technology Center
| |