Merge "arm64: topology: add MPIDR-based detection" (5b147579) · Commits · e / devices / android_kernel_sony_msm8994

arch/arm64/include/asm/cputype.h

+5 −0

Original line number	Diff line number	Diff line
		@@ -18,6 +18,8 @@

		#define INVALID_HWID ULONG_MAX

		#define MPIDR_UP_BITMASK (0x1 << 30)
		#define MPIDR_MT_BITMASK (0x1 << 24)
		#define MPIDR_HWID_BITMASK 0xff00ffffff

		#define MPIDR_LEVEL_BITS_SHIFT 3
		@@ -30,6 +32,9 @@
		#define MPIDR_AFFINITY_LEVEL(mpidr, level) \
		((mpidr >> MPIDR_LEVEL_SHIFT(level)) & MPIDR_LEVEL_MASK)

		#define MPIDR_AFF_MASK(level) \
		((u64)MPIDR_LEVEL_MASK << MPIDR_LEVEL_SHIFT(level))

		#define read_cpuid(reg) ({ \
		u64 __val; \
		asm("mrs %0, " #reg : "=r" (__val)); \

arch/arm64/kernel/topology.c

+42 −4

Original line number	Diff line number	Diff line
		@@ -20,6 +20,8 @@
		#include <linux/of.h>
		#include <linux/sched.h>

		#include <asm/cputype.h>
		#include <asm/smp_plat.h>
		#include <asm/topology.h>

		static int __init get_cpu_for_node(struct device_node *node)
		@@ -220,10 +222,8 @@ static void update_siblings_masks(unsigned int cpuid)
		int cpu;

		if (cpuid_topo->cluster_id == -1) {
		/*
		* DT does not contain topology information for this cpu.
		*/
		pr_debug("CPU%u: No topology information configured\n", cpuid);
		/* No topology information for this cpu ?! */
		pr_err("CPU%u: No topology information configured\n", cpuid);
		return;
		}

		@@ -249,6 +249,44 @@ static void update_siblings_masks(unsigned int cpuid)

		void store_cpu_topology(unsigned int cpuid)
		{
		struct cpu_topology *cpuid_topo = &cpu_topology[cpuid];
		u64 mpidr;

		if (cpuid_topo->cluster_id != -1)
		goto topology_populated;

		mpidr = read_cpuid_mpidr();

		/* Create cpu topology mapping based on MPIDR. */
		if (mpidr & MPIDR_UP_BITMASK) {
		/* Uniprocessor system */
		cpuid_topo->thread_id = -1;
		cpuid_topo->core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
		cpuid_topo->cluster_id = 0;
		} else if (mpidr & MPIDR_MT_BITMASK) {
		/* Multiprocessor system : Multi-threads per core */
		cpuid_topo->thread_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
		cpuid_topo->core_id = MPIDR_AFFINITY_LEVEL(mpidr, 1);
		cpuid_topo->cluster_id =
		((mpidr & MPIDR_AFF_MASK(2)) >> mpidr_hash.shift_aff[2] \|
		(mpidr & MPIDR_AFF_MASK(3)) >> mpidr_hash.shift_aff[3])
		>> mpidr_hash.shift_aff[1] >> mpidr_hash.shift_aff[0];
		} else {
		/* Multiprocessor system : Single-thread per core */
		cpuid_topo->thread_id = -1;
		cpuid_topo->core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
		cpuid_topo->cluster_id =
		((mpidr & MPIDR_AFF_MASK(1)) >> mpidr_hash.shift_aff[1] \|
		(mpidr & MPIDR_AFF_MASK(2)) >> mpidr_hash.shift_aff[2] \|
		(mpidr & MPIDR_AFF_MASK(3)) >> mpidr_hash.shift_aff[3])
		>> mpidr_hash.shift_aff[0];
		}

		pr_debug("CPU%u: cluster %d core %d thread %d mpidr %llx\n",
		cpuid, cpuid_topo->cluster_id, cpuid_topo->core_id,
		cpuid_topo->thread_id, mpidr);

		topology_populated:
		update_siblings_masks(cpuid);
		}