Merge branch 'pm-cpufreq'

Merge cpufreq updates for 5.19-rc1:

 - Fix cpufreq governor clean up code to avoid using kfree() directly
   to free kobject-based items (Kevin Hao).

 - Prepare cpufreq for powerpc's asm/prom.h cleanup (Christophe Leroy).

 - Make intel_pstate notify frequency invariance code when no_turbo is
   turned on and off (Chen Yu).

 - Add Sapphire Rapids OOB mode support to intel_pstate (Srinivas
   Pandruvada).

 - Make cpufreq avoid unnecessary frequency updates due to mismatch
   between hardware and the frequency table (Viresh Kumar).

 - Make remove_cpu_dev_symlink() clear the real_cpus mask to simplify
   code (Viresh Kumar).

 - Rearrange cpufreq_offline() and cpufreq_remove_dev() to make the
   calling convention for some driver callbacks consistent (Rafael
   Wysocki).

 - Avoid accessing half-initialized cpufreq policies from the show()
   and store() sysfs functions (Schspa Shi).

 - Rearrange cpufreq_offline() to make the calling convention for some
   driver callbacks consistent (Schspa Shi).

 - Update CPPC handling in cpufreq (Pierre Gondois):

   * Add per_cpu efficiency_class to the CPPC driver.
   * Make the CPPC driver Register EM based on efficiency class
     information.
   * Adjust _OSC for flexible address space in the ACPI platform
     initialization code and always set CPPC _OSC bits if CPPC_LIB is
     supported.
   * Assume no transition latency if no PCCT in the CPPC driver.
   * Add fast_switch and dvfs_possible_from_any_cpu support to the CPPC
     driver.

* pm-cpufreq:
  cpufreq: CPPC: Enable dvfs_possible_from_any_cpu
  cpufreq: CPPC: Enable fast_switch
  ACPI: CPPC: Assume no transition latency if no PCCT
  ACPI: bus: Set CPPC _OSC bits for all and when CPPC_LIB is supported
  ACPI: CPPC: Check _OSC for flexible address space
  cpufreq: make interface functions and lock holding state clear
  cpufreq: Abort show()/store() for half-initialized policies
  cpufreq: Rearrange locking in cpufreq_remove_dev()
  cpufreq: Split cpufreq_offline()
  cpufreq: Reorganize checks in cpufreq_offline()
  cpufreq: Clear real_cpus mask from remove_cpu_dev_symlink()
  cpufreq: intel_pstate: Support Sapphire Rapids OOB mode
  Revert "cpufreq: Fix possible race in cpufreq online error path"
  cpufreq: CPPC: Register EM based on efficiency class information
  cpufreq: CPPC: Add per_cpu efficiency_class
  cpufreq: Avoid unnecessary frequency updates due to mismatch
  cpufreq: Fix possible race in cpufreq online error path
  cpufreq: intel_pstate: Handle no_turbo in frequency invariance
  cpufreq: Prepare cleanup of powerpc's asm/prom.h
  cpufreq: governor: Use kobject release() method to free dbs_data

Author: rafaeljw

arch/arm64/kernel/smp.c

@@ -512,6 +512,7 @@ struct acpi_madt_generic_interrupt *acpi_cpu_get_madt_gicc(int cpu)
 {
 	return &cpu_madt_gicc[cpu];
 }
+EXPORT_SYMBOL_GPL(acpi_cpu_get_madt_gicc);
 
 /*
  * acpi_map_gic_cpu_interface - parse processor MADT entry

drivers/acpi/bus.c

@@ -278,6 +278,20 @@ bool osc_sb_apei_support_acked;
 bool osc_pc_lpi_support_confirmed;
 EXPORT_SYMBOL_GPL(osc_pc_lpi_support_confirmed);
 
+/*
+ * ACPI 6.2 Section 6.2.11.2 'Platform-Wide OSPM Capabilities':
+ *   Starting with ACPI Specification 6.2, all _CPC registers can be in
+ *   PCC, System Memory, System IO, or Functional Fixed Hardware address
+ *   spaces. OSPM support for this more flexible register space scheme is
+ *   indicated by the “Flexible Address Space for CPPC Registers” _OSC bit.
+ *
+ * Otherwise (cf ACPI 6.1, s8.4.7.1.1.X), _CPC registers must be in:
+ * - PCC or Functional Fixed Hardware address space if defined
+ * - SystemMemory address space (NULL register) if not defined
+ */
+bool osc_cpc_flexible_adr_space_confirmed;
+EXPORT_SYMBOL_GPL(osc_cpc_flexible_adr_space_confirmed);
+
 /*
  * ACPI 6.4 Operating System Capabilities for USB.
  */
@@ -315,12 +329,15 @@ static void acpi_bus_osc_negotiate_platform_control(void)
 #endif
 #ifdef CONFIG_X86
 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_GENERIC_INITIATOR_SUPPORT;
-	if (boot_cpu_has(X86_FEATURE_HWP)) {
-		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_SUPPORT;
-		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPCV2_SUPPORT;
-	}
 #endif
 
+#ifdef CONFIG_ACPI_CPPC_LIB
+	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_SUPPORT;
+	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPCV2_SUPPORT;
+#endif
+
+	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_FLEXIBLE_ADR_SPACE;
+
 	if (IS_ENABLED(CONFIG_SCHED_MC_PRIO))
 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_DIVERSE_HIGH_SUPPORT;
 
@@ -341,10 +358,9 @@ static void acpi_bus_osc_negotiate_platform_control(void)
 		return;
 	}
 
-#ifdef CONFIG_X86
-	if (boot_cpu_has(X86_FEATURE_HWP))
-		osc_sb_cppc_not_supported = !(capbuf_ret[OSC_SUPPORT_DWORD] &
-				(OSC_SB_CPC_SUPPORT | OSC_SB_CPCV2_SUPPORT));
+#ifdef CONFIG_ACPI_CPPC_LIB
+	osc_sb_cppc_not_supported = !(capbuf_ret[OSC_SUPPORT_DWORD] &
+			(OSC_SB_CPC_SUPPORT | OSC_SB_CPCV2_SUPPORT));
 #endif
 
 	/*
@@ -366,6 +382,8 @@ static void acpi_bus_osc_negotiate_platform_control(void)
 			capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_PCLPI_SUPPORT;
 		osc_sb_native_usb4_support_confirmed =
 			capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_NATIVE_USB4_SUPPORT;
+		osc_cpc_flexible_adr_space_confirmed =
+			capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_CPC_FLEXIBLE_ADR_SPACE;
 	}
 
 	kfree(context.ret.pointer);

drivers/acpi/cppc_acpi.c

@@ -100,6 +100,16 @@ static DEFINE_PER_CPU(struct cpc_desc *, cpc_desc_ptr);
 				(cpc)->cpc_entry.reg.space_id ==	\
 				ACPI_ADR_SPACE_PLATFORM_COMM)
 
+/* Check if a CPC register is in SystemMemory */
+#define CPC_IN_SYSTEM_MEMORY(cpc) ((cpc)->type == ACPI_TYPE_BUFFER &&	\
+				(cpc)->cpc_entry.reg.space_id ==	\
+				ACPI_ADR_SPACE_SYSTEM_MEMORY)
+
+/* Check if a CPC register is in SystemIo */
+#define CPC_IN_SYSTEM_IO(cpc) ((cpc)->type == ACPI_TYPE_BUFFER &&	\
+				(cpc)->cpc_entry.reg.space_id ==	\
+				ACPI_ADR_SPACE_SYSTEM_IO)
+
 /* Evaluates to True if reg is a NULL register descriptor */
 #define IS_NULL_REG(reg) ((reg)->space_id ==  ACPI_ADR_SPACE_SYSTEM_MEMORY && \
 				(reg)->address == 0 &&			\
@@ -424,6 +434,24 @@ bool acpi_cpc_valid(void)
 }
 EXPORT_SYMBOL_GPL(acpi_cpc_valid);
 
+bool cppc_allow_fast_switch(void)
+{
+	struct cpc_register_resource *desired_reg;
+	struct cpc_desc *cpc_ptr;
+	int cpu;
+
+	for_each_possible_cpu(cpu) {
+		cpc_ptr = per_cpu(cpc_desc_ptr, cpu);
+		desired_reg = &cpc_ptr->cpc_regs[DESIRED_PERF];
+		if (!CPC_IN_SYSTEM_MEMORY(desired_reg) &&
+				!CPC_IN_SYSTEM_IO(desired_reg))
+			return false;
+	}
+
+	return true;
+}
+EXPORT_SYMBOL_GPL(cppc_allow_fast_switch);
+
 /**
  * acpi_get_psd_map - Map the CPUs in the freq domain of a given cpu
  * @cpu: Find all CPUs that share a domain with cpu.
@@ -736,6 +764,11 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
 				if (gas_t->address) {
 					void __iomem *addr;
 
+					if (!osc_cpc_flexible_adr_space_confirmed) {
+						pr_debug("Flexible address space capability not supported\n");
+						goto out_free;
+					}
+
 					addr = ioremap(gas_t->address, gas_t->bit_width/8);
 					if (!addr)
 						goto out_free;
@@ -758,6 +791,10 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
 						 gas_t->address);
 					goto out_free;
 				}
+				if (!osc_cpc_flexible_adr_space_confirmed) {
+					pr_debug("Flexible address space capability not supported\n");
+					goto out_free;
+				}
 			} else {
 				if (gas_t->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE || !cpc_ffh_supported()) {
 					/* Support only PCC, SystemMemory, SystemIO, and FFH type regs. */
@@ -1447,6 +1484,9 @@ EXPORT_SYMBOL_GPL(cppc_set_perf);
  * transition latency for performance change requests. The closest we have
  * is the timing information from the PCCT tables which provides the info
  * on the number and frequency of PCC commands the platform can handle.
+ *
+ * If desired_reg is in the SystemMemory or SystemIo ACPI address space,
+ * then assume there is no latency.
  */
 unsigned int cppc_get_transition_latency(int cpu_num)
 {
@@ -1472,7 +1512,9 @@ unsigned int cppc_get_transition_latency(int cpu_num)
 		return CPUFREQ_ETERNAL;
 
 	desired_reg = &cpc_desc->cpc_regs[DESIRED_PERF];
-	if (!CPC_IN_PCC(desired_reg))
+	if (CPC_IN_SYSTEM_MEMORY(desired_reg) || CPC_IN_SYSTEM_IO(desired_reg))
+		return 0;
+	else if (!CPC_IN_PCC(desired_reg))
 		return CPUFREQ_ETERNAL;
 
 	if (pcc_ss_id < 0)