powercap: intel_rapl: Allow interface drivers to configure rapl_defaults

RAPL default settings vary across different RAPL interfaces (MSR, TPMI,
MMIO). Currently, these defaults are stored in the common RAPL driver,
which requires interface-specific handling logic and makes the common
layer unnecessarily complex. There is no strong reason for the common
code to own these defaults, since they are inherently
interface-specific.

To prepare for moving default configuration into the individual
interface drivers,

 1. Move struct rapl_defaults into a shared header so that interface
    drivers can directly populate their own default settings.

 2. Change the @defaults field in struct rapl_if_priv from void * to
    const struct rapl_defaults * to improve type safety and readability
    and update the common driver to use the typed defaults structure.

 3. Update all internal getter functions and local pointers to use
    const struct rapl_defaults * to maintain const-correctness.

 4. Rename and export the common helper functions (check_unit,
    set_floor_freq, compute_time_window) so interface drivers may
    reuse or override them as appropriate.

No functional changes. This is a preparatory refactoring to allow
interface drivers to supply their own RAPL default settings.

Co-developed-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Link: https://patch.msgid.link/20260212233044.329790-9-sathyanarayanan.kuppuswamy@linux.intel.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 15 insertions, 2 deletions

diff --git a/include/linux/intel_rapl.h b/include/linux/intel_rapl.h
index fa1f328d6712..6d694099a3ad 100644
--- a/include/linux/intel_rapl.h
+++ b/include/linux/intel_rapl.h
@@ -128,6 +128,16 @@ struct reg_action {
 	int err;
 };
 
+struct rapl_defaults {
+	u8 floor_freq_reg_addr;
+	int (*check_unit)(struct rapl_domain *rd);
+	void (*set_floor_freq)(struct rapl_domain *rd, bool mode);
+	u64 (*compute_time_window)(struct rapl_domain *rd, u64 val, bool to_raw);
+	unsigned int dram_domain_energy_unit;
+	unsigned int psys_domain_energy_unit;
+	bool spr_psys_bits;
+};
+
 /**
  * struct rapl_if_priv: private data for different RAPL interfaces
  * @control_type:		Each RAPL interface must have its own powercap
@@ -142,7 +152,7 @@ struct reg_action {
  *				registers.
  * @write_raw:			Callback for writing RAPL interface specific
  *				registers.
- * @defaults:			internal pointer to interface default settings
+ * @defaults:			pointer to default settings
  * @rpi:			internal pointer to interface primitive info
  */
 struct rapl_if_priv {
@@ -154,7 +164,7 @@ struct rapl_if_priv {
 	int limits[RAPL_DOMAIN_MAX];
 	int (*read_raw)(int id, struct reg_action *ra, bool pmu_ctx);
 	int (*write_raw)(int id, struct reg_action *ra);
-	void *defaults;
+	const struct rapl_defaults *defaults;
 	void *rpi;
 };
 
@@ -211,6 +221,9 @@ void rapl_remove_package_cpuslocked(struct rapl_package *rp);
 struct rapl_package *rapl_find_package_domain(int id, struct rapl_if_priv *priv, bool id_is_cpu);
 struct rapl_package *rapl_add_package(int id, struct rapl_if_priv *priv, bool id_is_cpu);
 void rapl_remove_package(struct rapl_package *rp);
+int rapl_default_check_unit(struct rapl_domain *rd);
+void rapl_default_set_floor_freq(struct rapl_domain *rd, bool mode);
+u64 rapl_default_compute_time_window(struct rapl_domain *rd, u64 value, bool to_raw);
 
 #ifdef CONFIG_PERF_EVENTS
 int rapl_package_add_pmu(struct rapl_package *rp);