cpufreq: intel_pstate: Use HYBRID_SCALING_FACTOR_ADL for Bartlett Lake

Bartlett Lake P-core only SKUs (e.g. Intel Core 9 273PE)
do not report X86_FEATURE_HYBRID_CPU and are not in
intel_hybrid_scaling_factor[].  In hwp_get_cpu_scaling(), the
non-hybrid fallback then applies core_get_scaling() (100000),
producing cpuinfo_max_freq values that exceed the documented Max
Turbo Frequency:

  intel_pstate: CPU0: PERF_CTL turbo = 57
  intel_pstate: CPU0: HWP_CAP guaranteed = 30
  intel_pstate: CPU0: HWP_CAP highest = 70
  intel_pstate: CPU0: HWP-to-frequency scaling factor: 100000
  intel_pstate: set_policy cpuinfo.max 7000000 policy->max 7000000
  ...
  intel_pstate: CPU12: PERF_CTL turbo = 57
  intel_pstate: CPU12: HWP_CAP guaranteed = 30
  intel_pstate: CPU12: HWP_CAP highest = 73
  intel_pstate: CPU12: HWP-to-frequency scaling factor: 100000
  intel_pstate: set_policy cpuinfo.max 7300000 policy->max 7300000
  ...

Per the Intel datasheet [1], the Intel Core 9 273PE specifies:

  Performance-cores:                                 12
  Efficient-cores:                                   0
  Max Turbo Frequency:                               5.7 GHz
  Intel Thermal Velocity Boost Frequency:            5.7 GHz
  Intel Turbo Boost Max Technology 3.0 Frequency:    5.6 GHz
  Performance-core Max Turbo Frequency:              5.4 GHz
  Performance-core Base Frequency:                   2.3 GHz

Bartlett Lake P-cores are Raptor Cove cores, per
commit d466304c4322 ("x86/cpu: Add CPU model number for Bartlett
Lake CPUs with Raptor Cove cores").  The Alder Lake and Raptor Lake
P-core entries in intel_hybrid_scaling_factor[] use
HYBRID_SCALING_FACTOR_ADL (78741).  The same factor applies to
Bartlett Lake.

Add Bartlett Lake to intel_hybrid_scaling_factor[] with
HYBRID_SCALING_FACTOR_ADL so HWP performance levels map to the
correct CPU frequencies matching the datasheet's Max Turbo Frequency.

Link: https://www.intel.com/content/www/us/en/products/sku/245717/intel-core-9-processor-273pe-36m-cache-up-to-5-70-ghz/specifications.html
Signed-off-by: Henry Tseng <henrytseng@qnap.com>
[ rjw: Changelog tweak ]
Link: https://patch.msgid.link/20260513102847.75179-1-henrytseng@qnap.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 978e2b604ac86df7eefb9184d67c404d9d621086..1f093e34643014a93b424397247b31837fe246ed 100644 (file)
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -3734,6 +3734,7 @@ static const struct x86_cpu_id intel_hybrid_scaling_factor[] = {
        X86_MATCH_VFM(INTEL_RAPTORLAKE, HYBRID_SCALING_FACTOR_ADL),
        X86_MATCH_VFM(INTEL_RAPTORLAKE_P, HYBRID_SCALING_FACTOR_ADL),
        X86_MATCH_VFM(INTEL_RAPTORLAKE_S, HYBRID_SCALING_FACTOR_ADL),
+       X86_MATCH_VFM(INTEL_BARTLETTLAKE, HYBRID_SCALING_FACTOR_ADL),
        X86_MATCH_VFM(INTEL_METEORLAKE_L, HYBRID_SCALING_FACTOR_MTL),
        X86_MATCH_VFM(INTEL_LUNARLAKE_M, HYBRID_SCALING_FACTOR_LNL),
        {}