Re: [PATCH] intel_idle: Add Jasper Lake and Elkhart Lake support

["Zhang, Rui" <rui.zhang@intel.com>]

BTW, Add Rafael.

On Fri, 2024-07-26 at 14:51 +0800, Zhang, Rui wrote:
> On Fri, 2024-07-26 at 14:26 +0800, Kai-Heng Feng wrote:
> > Without proper C-state support, the CPU can take long time to exit
> > to
> > C0
> > to handle IRQ and perform DMA.
> 
> Can you provide more details?
> 
> Say, what cstate is entered w/ and w/o this patch?
> 
> can you show the output of "grep .
> /sys/devices/system/cpu/cpu0/cpuidle/state*/*" without this patch?
> 
> > 
> > The data collect via wult shows the latency is similar to Broxton,
> > so
> > use the existing table to support C-state on JSL and EHL.
> 
> so you have done cstate measurement on the EHL using wult?
> can you share more details about the measurement results?
> 
> thanks,
> rui
> 
> > 
> > Link: https://bugzilla.kernel.org/show_bug.cgi?id=219023
> > Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
> > ---
> >  drivers/idle/intel_idle.c | 2 ++
> >  1 file changed, 2 insertions(+)
> > 
> > diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
> > index 9aab7abc2ae9..eb6975a1d083 100644
> > --- a/drivers/idle/intel_idle.c
> > +++ b/drivers/idle/intel_idle.c
> > @@ -1538,6 +1538,8 @@ static const struct x86_cpu_id
> > intel_idle_ids[]
> > __initconst = {
> >         X86_MATCH_VFM(INTEL_ATOM_GOLDMONT,      &idle_cpu_bxt),
> >         X86_MATCH_VFM(INTEL_ATOM_GOLDMONT_PLUS, &idle_cpu_bxt),
> >         X86_MATCH_VFM(INTEL_ATOM_GOLDMONT_D,    &idle_cpu_dnv),
> > +       X86_MATCH_VFM(INTEL_ATOM_TREMONT,       &idle_cpu_bxt),
> > +       X86_MATCH_VFM(INTEL_ATOM_TREMONT_L,     &idle_cpu_bxt),
> >         X86_MATCH_VFM(INTEL_ATOM_TREMONT_D,     &idle_cpu_snr),
> >         X86_MATCH_VFM(INTEL_ATOM_CRESTMONT,     &idle_cpu_grr),
> >         X86_MATCH_VFM(INTEL_ATOM_CRESTMONT_X,   &idle_cpu_srf),
>