powercap: intel_rapl: Make cpu optional for rapl_package

MSR RAPL Interface always removes a rapl_package when all the CPUs in
that rapl_package are offlined. This is because it relies on an online
CPU to access the MSR.

But for RAPL Interface using MMIO registers, when all the cpus within
the rapl_package are offlined,
1. the register can still be accessed
2. monitoring and setting the Power Pimits for the rapl_package is still
   meaningful because of uncore power.

This means that, a valid rapl_package doesn't rely on one or more cpus
being onlined.

For this sense, make cpu optional for rapl_package. A rapl_package can
be registered either using a CPU id to represent the physical
package/die, or using the physical package id directly.

Note that, the thermal throttling interrupt is not disabled via
MSR_IA32_PACKAGE_THERM_INTERRUPT for such rapl_package at the moment.
If it is still needed in the future, this can be achieved by selecting
an onlined CPU using the physical package id.

Note that, processor_thermal_rapl, the current MMIO RAPL Interface
driver, can also be converted to register using a package id instead.
But this is not done right now because processor_thermal_rapl driver
works on single-package systems only, and offlining the only package
will not happen. So keep the previous logic.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/include/linux/intel_rapl.h b/include/linux/intel_rapl.h
index d07b460bac3b..51509f35027b 100644
--- a/include/linux/intel_rapl.h
+++ b/include/linux/intel_rapl.h
@@ -135,8 +135,8 @@ struct rapl_if_priv {
 	u64 reg_unit;
 	u64 regs[RAPL_DOMAIN_MAX][RAPL_DOMAIN_REG_MAX];
 	int limits[RAPL_DOMAIN_MAX];
-	int (*read_raw)(int cpu, struct reg_action *ra);
-	int (*write_raw)(int cpu, struct reg_action *ra);
+	int (*read_raw)(int id, struct reg_action *ra);
+	int (*write_raw)(int id, struct reg_action *ra);
 	void *defaults;
 	void *rpi;
 };
@@ -161,8 +161,8 @@ struct rapl_package {
 	struct rapl_if_priv *priv;
 };
 
-struct rapl_package *rapl_find_package_domain(int cpu, struct rapl_if_priv *priv);
-struct rapl_package *rapl_add_package(int cpu, struct rapl_if_priv *priv);
+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);
 
 #endif /* __INTEL_RAPL_H__ */