[PATCH v2 2/2] cpufreq: intel_pstate: Use HYBRID_SCALING_FACTOR_ADL for Bartlett Lake

[Henry Tseng <henrytseng@qnap.com>]

Bartlett Lake shares the same HWP-to-PERF_CTL scaling factor as Alder
Lake / Raptor Lake P-cores.  Add Bartlett Lake to
intel_hybrid_scaling_factor[] with HYBRID_SCALING_FACTOR_ADL so HWP
performance levels map to the correct CPU frequencies.

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

Because this CPU has no E-cores and does not report
X86_FEATURE_HYBRID_CPU, hwp_get_cpu_scaling() returns 100000 (the
default core scaling).  In intel_pstate_get_cpu_pstates(), the
condition cpu->pstate.scaling == perf_ctl_scaling then takes the
early path that simply multiplies HWP performance levels by 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: HWP_CAP highest = 73
  intel_pstate: CPU12: HWP-to-frequency scaling factor: 100000
  intel_pstate: set_policy cpuinfo.max 7300000 policy->max 7300000

With this patch, the registered HYBRID_SCALING_FACTOR_ADL (78741) is
used:

  intel_pstate: hybrid scaling factor: 78741
  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: 78741
  intel_pstate: set_policy cpuinfo.max 5500000 policy->max 5500000
  ...
  intel_pstate: CPU12: HWP_CAP highest = 73
  intel_pstate: CPU12: HWP-to-frequency scaling factor: 78741
  intel_pstate: set_policy cpuinfo.max 5700000 policy->max 5700000

The reported cpuinfo_max_freq (5.5/5.7 GHz) now matches the
datasheet's Max Turbo Frequency.

[1] 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>
---
 drivers/cpufreq/intel_pstate.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index d39592e86570..82e82a70cacb 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -3737,6 +3737,7 @@ 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),
 	{}
-- 
2.43.0