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From: "Rafael J. Wysocki" <rafael@kernel.org>
To: Linux PM <linux-pm@vger.kernel.org>
Cc: Henry Tseng <henrytseng@qnap.com>,
	Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
	LKML <linux-kernel@vger.kernel.org>
Subject: [PATCH v1] cpufreq: intel_pstate: Use correct scaling factor on Raptor Lake-E
Date: Tue, 12 May 2026 21:20:30 +0200	[thread overview]
Message-ID: <4523296.ejJDZkT8p0@rafael.j.wysocki> (raw)

From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>

Raptor Lake-E has the same processor ID as Raptor Lake-S, so there is
an entry in intel_hybrid_scaling_factor[] for it.  It does not contain
E-cores though and hybrid_get_cpu_type() returns 0 for its P-cores, so
they get the default "core" scaling factor.  However, the original
Raptor Lake scaling factor for P-cores still needs to be used for
mapping the HWP performance levels of the P-cores in Raptor Lake-E to
frequency, as though they were part of a real hybrid system.

To address this, update hwp_get_cpu_scaling() to return
hybrid_scaling_factor, which is the P-core scaling factor
retrieved from intel_hybrid_scaling_factor[], for all CPUs
that are not enumerated as E-cores.

Fixes: 9b18d536b124 ("cpufreq: intel_pstate: Use CPPC to get scaling factors")
Link: https://lore.kernel.org/all/20260511235328.2018458-1-srinivas.pandruvada@linux.intel.com/
Reported-by: Henry Tseng <henrytseng@qnap.com>
Closes: https://lore.kernel.org/linux-pm/20260508063032.3248602-1-henrytseng@qnap.com/
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: All applicable <stable@vger.kernel.org>
---
 drivers/cpufreq/intel_pstate.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -2279,7 +2279,7 @@ static int hwp_get_cpu_scaling(int cpu)
 		 * Return the hybrid scaling factor for P-cores and use the
 		 * default core scaling for E-cores.
 		 */
-		if (hybrid_get_cpu_type(cpu) == INTEL_CPU_TYPE_CORE)
+		if (hybrid_get_cpu_type(cpu) != INTEL_CPU_TYPE_ATOM)
 			return hybrid_scaling_factor;
 
 		return core_get_scaling();




                 reply	other threads:[~2026-05-12 19:20 UTC|newest]

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