Re: [PATCH v2] eal/x86: add AMD vendor check to choose TSC calibration

[Thomas Monjalon <thomas@monjalon.net>]

23/11/2023 11:29, Ferruh Yigit:
> On 11/23/2023 7:27 AM, Sivaprasad Tummala wrote:
> > AMD Epyc processors doesn't support get_tsc_freq_arch().
> > The patch allows graceful return to allow fallback to
> > alternate TSC calibration.
> > 
> > Fixes: 3dbc565e81a0 ("timer: honor arch-specific TSC frequency query")
> > Cc: jerin.jacob@caviumnetworks.com
> > Cc: stable@dpdk.org
> > 
> > Signed-off-by: Sivaprasad Tummala <sivaprasad.tummala@amd.com>
> 
> Acked-by: Ferruh Yigit <ferruh.yigit@amd.com>

Applied

I don't want to block longer this fix,
but I am not satisfied with the implementation.
David, Ferruh, Bruce and Morten were proposing some abstractions
for CPU features identification.
I think we should start a new enum in rte_cpuflags.h defining some
common CPU features, example is timer calibration here.

The function get_tsc_freq_arch() was already doing some __cpuid calls,
so it's one more, but please could you work on abstracting it in EAL?

Thank you