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The parameter does not support any > other platform. For example, Meteor Lake has a similar C1/C1E limitation, > but the parameter does not support Meteor Lake. This indicates that the > parameter is not very useful. > > Generally, independent C1 and C1E are important for server platforms where > low latency is key. However, they are not as important for client platforms, > like Alder Lake, where C1E providing better energy savings is generally > preferred. > > The parameter was originally introduced for Sapphire Rapids Xeon: > da0e58c038e6 intel_idle: add 'preferred_cstates' module argument > > Later it was added to Alder Lake: > d1cf8bbfed1ed ("intel_idle: Add AlderLake support") > > But it was removed from Sapphire Rapids when firmware fixed the C1/C1E > limitation: > 1548fac47a114 ("intel_idle: make SPR C1 and C1E be independent") > > So Alder Lake is the only platform left where this parameter has any effect. > Remove this parameter to simplify the driver and reduce maintenance burden. > > Signed-off-by: Artem Bityutskiy > Link: https://patch.msgid.link/20251215111300.132803-1-dedekind1@gmail.com > Signed-off-by: Rafael J. Wysocki > Origin: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git a36dc37b5672 > Signed-off-by: Jan Beulich Acked-by: Roger Pau Monné Thanks, Roger.