On Thu, Aug 18, 2022 at 03:05:19PM +0200, Jan Beulich wrote: > From: Artem Bityutskiy <artem.bityuts...@linux.intel.com> > > This patch partially reverts the changes made by the following commit: > > da0e58c038e6 intel_idle: add 'preferred_cstates' module argument > > As that commit describes, on early Sapphire Rapids Xeon platforms the C1 and > C1E states were mutually exclusive, so that users could only have either C1 > and > C6, or C1E and C6. > > However, Intel firmware engineers managed to remove this limitation and make > C1 > and C1E to be completely independent, just like on previous Xeon platforms. > > Therefore, this patch: > * Removes commentary describing the old, and now non-existing SPR C1E > limitation. > * Marks SPR C1E as available by default. > * Removes the 'preferred_cstates' parameter handling for SPR. Both C1 and > C1E will be available regardless of 'preferred_cstates' value. > > We expect that all SPR systems are shipping with new firmware, which includes > the C1/C1E improvement. > > Signed-off-by: Artem Bityutskiy <artem.bityuts...@linux.intel.com> > Signed-off-by: Rafael J. Wysocki <rafael.j.wyso...@intel.com> > Origin: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git > 1548fac47a11 > Signed-off-by: Jan Beulich <jbeul...@suse.com>
Acked-by: Roger Pau Monné <roger....@citrix.com> I guess we need to be careful of running this on pre-production hardware then? Thanks, Roger.
