diff options
| author | Nathan Lynch <ntl@pobox.com> | 2008-07-27 15:24:54 +1000 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2008-07-28 16:30:52 +1000 |
| commit | e9efed3b80a83e44b98fc626f3268ae072550b84 (patch) | |
| tree | cbe7cc897dc112e2eb93f9bbded5aa3a8e6e0bf3 | |
| parent | 440a0857e32a05979fb01fc59ea454a723e80e4b (diff) | |
| download | linux-stable-e9efed3b80a83e44b98fc626f3268ae072550b84.tar.gz linux-stable-e9efed3b80a83e44b98fc626f3268ae072550b84.tar.bz2 linux-stable-e9efed3b80a83e44b98fc626f3268ae072550b84.zip | |
powerpc: Make core id information available to userspace
Existing Open Firmware practice is to report each processor core as a
separate node in the device tree. Report the value of the "reg" OF
property corresponding to a logical CPU's device node as the core_id
attribute in /sys/devices/system/cpu/cpu*/topology/core_id.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| -rw-r--r-- | arch/powerpc/kernel/smp.c | 23 | ||||
| -rw-r--r-- | include/asm-powerpc/smp.h | 1 | ||||
| -rw-r--r-- | include/asm-powerpc/topology.h | 1 |
3 files changed, 25 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index f7a2f81b5b7d..5337ca7bb649 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -380,6 +380,29 @@ int __cpuinit __cpu_up(unsigned int cpu) return 0; } +/* Return the value of the reg property corresponding to the given + * logical cpu. + */ +int cpu_to_core_id(int cpu) +{ + struct device_node *np; + const int *reg; + int id = -1; + + np = of_get_cpu_node(cpu, NULL); + if (!np) + goto out; + + reg = of_get_property(np, "reg", NULL); + if (!reg) + goto out; + + id = *reg; +out: + of_node_put(np); + return id; +} + /* Must be called when no change can occur to cpu_present_map, * i.e. during cpu online or offline. */ diff --git a/include/asm-powerpc/smp.h b/include/asm-powerpc/smp.h index 32e910006250..4d28e1e4521b 100644 --- a/include/asm-powerpc/smp.h +++ b/include/asm-powerpc/smp.h @@ -63,6 +63,7 @@ extern int smp_hw_index[]; DECLARE_PER_CPU(cpumask_t, cpu_sibling_map); DECLARE_PER_CPU(cpumask_t, cpu_core_map); +extern int cpu_to_core_id(int cpu); /* Since OpenPIC has only 4 IPIs, we use slightly different message numbers. * diff --git a/include/asm-powerpc/topology.h b/include/asm-powerpc/topology.h index f00e8e551738..c32da6f97999 100644 --- a/include/asm-powerpc/topology.h +++ b/include/asm-powerpc/topology.h @@ -109,6 +109,7 @@ static inline void sysfs_remove_device_from_node(struct sys_device *dev, #define topology_thread_siblings(cpu) (per_cpu(cpu_sibling_map, cpu)) #define topology_core_siblings(cpu) (per_cpu(cpu_core_map, cpu)) +#define topology_core_id(cpu) (cpu_to_core_id(cpu)) #endif #endif |