arm: Use common cpu_topology structure and functions.

Currently, ARM32 and ARM64 uses different data structures to represent
their cpu topologies. Since, we are moving the ARM64 topology to common
code to be used by other architectures, we can reuse that for ARM32 as
well.

Take this opprtunity to remove the redundant functions from ARM32 and
reuse the common code instead.

To: Russell King <linux@armlinux.org.uk>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Sudeep Holla <sudeep.holla@arm.com> (on TC2)
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>

Author: atishp04

arch/arm/include/asm/topology.h

@@ -5,26 +5,6 @@
 #ifdef CONFIG_ARM_CPU_TOPOLOGY
 
 #include <linux/cpumask.h>
-
-struct cputopo_arm {
-	int thread_id;
-	int core_id;
-	int socket_id;
-	cpumask_t thread_sibling;
-	cpumask_t core_sibling;
-};
-
-extern struct cputopo_arm cpu_topology[NR_CPUS];
-
-#define topology_physical_package_id(cpu)	(cpu_topology[cpu].socket_id)
-#define topology_core_id(cpu)		(cpu_topology[cpu].core_id)
-#define topology_core_cpumask(cpu)	(&cpu_topology[cpu].core_sibling)
-#define topology_sibling_cpumask(cpu)	(&cpu_topology[cpu].thread_sibling)
-
-void init_cpu_topology(void);
-void store_cpu_topology(unsigned int cpuid);
-const struct cpumask *cpu_coregroup_mask(int cpu);
-
 #include <linux/arch_topology.h>
 
 /* Replace task scheduler's default frequency-invariant accounting */

arch/arm/kernel/topology.c

@@ -177,17 +177,6 @@ static inline void parse_dt_topology(void) {}
 static inline void update_cpu_capacity(unsigned int cpuid) {}
 #endif
 
- /*
- * cpu topology table
- */
-struct cputopo_arm cpu_topology[NR_CPUS];
-EXPORT_SYMBOL_GPL(cpu_topology);
-
-const struct cpumask *cpu_coregroup_mask(int cpu)
-{
-	return &cpu_topology[cpu].core_sibling;
-}
-
 /*
  * The current assumption is that we can power gate each core independently.
  * This will be superseded by DT binding once available.
@@ -197,40 +186,14 @@ const struct cpumask *cpu_corepower_mask(int cpu)
 	return &cpu_topology[cpu].thread_sibling;
 }
 
-static void update_siblings_masks(unsigned int cpuid)
-{
-	struct cputopo_arm *cpu_topo, *cpuid_topo = &cpu_topology[cpuid];
-	int cpu;
-
-	/* update core and thread sibling masks */
-	for_each_possible_cpu(cpu) {
-		cpu_topo = &cpu_topology[cpu];
-
-		if (cpuid_topo->socket_id != cpu_topo->socket_id)
-			continue;
-
-		cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
-		if (cpu != cpuid)
-			cpumask_set_cpu(cpu, &cpuid_topo->core_sibling);
-
-		if (cpuid_topo->core_id != cpu_topo->core_id)
-			continue;
-
-		cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling);
-		if (cpu != cpuid)
-			cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
-	}
-	smp_wmb();
-}
-
 /*
  * store_cpu_topology is called at boot when only one cpu is running
  * and with the mutex cpu_hotplug.lock locked, when several cpus have booted,
  * which prevents simultaneous write access to cpu_topology array
  */
 void store_cpu_topology(unsigned int cpuid)
 {
-	struct cputopo_arm *cpuid_topo = &cpu_topology[cpuid];
+	struct cpu_topology *cpuid_topo = &cpu_topology[cpuid];
 	unsigned int mpidr;
 
 	/* If the cpu topology has been already set, just return */
@@ -250,12 +213,12 @@ void store_cpu_topology(unsigned int cpuid)
 			/* core performance interdependency */
 			cpuid_topo->thread_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
 			cpuid_topo->core_id = MPIDR_AFFINITY_LEVEL(mpidr, 1);
-			cpuid_topo->socket_id = MPIDR_AFFINITY_LEVEL(mpidr, 2);
+			cpuid_topo->package_id = MPIDR_AFFINITY_LEVEL(mpidr, 2);
 		} else {
 			/* largely independent cores */
 			cpuid_topo->thread_id = -1;
 			cpuid_topo->core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
-			cpuid_topo->socket_id = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+			cpuid_topo->package_id = MPIDR_AFFINITY_LEVEL(mpidr, 1);
 		}
 	} else {
 		/*
@@ -265,7 +228,7 @@ void store_cpu_topology(unsigned int cpuid)
 		 */
 		cpuid_topo->thread_id = -1;
 		cpuid_topo->core_id = 0;
-		cpuid_topo->socket_id = -1;
+		cpuid_topo->package_id = -1;
 	}
 
 	update_siblings_masks(cpuid);
@@ -275,7 +238,7 @@ void store_cpu_topology(unsigned int cpuid)
 	pr_info("CPU%u: thread %d, cpu %d, socket %d, mpidr %x\n",
 		cpuid, cpu_topology[cpuid].thread_id,
 		cpu_topology[cpuid].core_id,
-		cpu_topology[cpuid].socket_id, mpidr);
+		cpu_topology[cpuid].package_id, mpidr);
 }
 
 static inline int cpu_corepower_flags(void)
@@ -298,18 +261,7 @@ static struct sched_domain_topology_level arm_topology[] = {
  */
 void __init init_cpu_topology(void)
 {
-	unsigned int cpu;
-
-	/* init core mask and capacity */
-	for_each_possible_cpu(cpu) {
-		struct cputopo_arm *cpu_topo = &(cpu_topology[cpu]);
-
-		cpu_topo->thread_id = -1;
-		cpu_topo->core_id =  -1;
-		cpu_topo->socket_id = -1;
-		cpumask_clear(&cpu_topo->core_sibling);
-		cpumask_clear(&cpu_topo->thread_sibling);
-	}
+	reset_cpu_topology();
 	smp_wmb();
 
 	parse_dt_topology();

drivers/base/arch_topology.c

@@ -423,6 +423,7 @@ static int __init parse_dt_topology(void)
 	of_node_put(cn);
 	return ret;
 }
+#endif
 
 /*
  * cpu topology table
@@ -488,7 +489,7 @@ static void clear_cpu_topology(int cpu)
 	cpumask_set_cpu(cpu, &cpu_topo->thread_sibling);
 }
 
-static void __init reset_cpu_topology(void)
+void __init reset_cpu_topology(void)
 {
 	unsigned int cpu;
 
@@ -523,6 +524,7 @@ __weak int __init parse_acpi_topology(void)
 	return 0;
 }
 
+#if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
 void __init init_cpu_topology(void)
 {
 	reset_cpu_topology();

include/linux/arch_topology.h

@@ -54,11 +54,9 @@ extern struct cpu_topology cpu_topology[NR_CPUS];
 void init_cpu_topology(void);
 void store_cpu_topology(unsigned int cpuid);
 const struct cpumask *cpu_coregroup_mask(int cpu);
-#endif
-
-#if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
 void update_siblings_masks(unsigned int cpu);
-#endif
 void remove_cpu_topology(unsigned int cpuid);
+void reset_cpu_topology(void);
+#endif
 
 #endif /* _LINUX_ARCH_TOPOLOGY_H_ */