diff options
author | Nathan Lynch <ntl@pobox.com> | 2008-07-27 01:24:54 -0400 |
---|---|---|
committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2008-07-28 02:30:52 -0400 |
commit | e9efed3b80a83e44b98fc626f3268ae072550b84 (patch) | |
tree | cbe7cc897dc112e2eb93f9bbded5aa3a8e6e0bf3 /arch/powerpc | |
parent | 440a0857e32a05979fb01fc59ea454a723e80e4b (diff) |
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>
Diffstat (limited to 'arch/powerpc')
-rw-r--r-- | arch/powerpc/kernel/smp.c | 23 |
1 files changed, 23 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) | |||
380 | return 0; | 380 | return 0; |
381 | } | 381 | } |
382 | 382 | ||
383 | /* Return the value of the reg property corresponding to the given | ||
384 | * logical cpu. | ||
385 | */ | ||
386 | int cpu_to_core_id(int cpu) | ||
387 | { | ||
388 | struct device_node *np; | ||
389 | const int *reg; | ||
390 | int id = -1; | ||
391 | |||
392 | np = of_get_cpu_node(cpu, NULL); | ||
393 | if (!np) | ||
394 | goto out; | ||
395 | |||
396 | reg = of_get_property(np, "reg", NULL); | ||
397 | if (!reg) | ||
398 | goto out; | ||
399 | |||
400 | id = *reg; | ||
401 | out: | ||
402 | of_node_put(np); | ||
403 | return id; | ||
404 | } | ||
405 | |||
383 | /* Must be called when no change can occur to cpu_present_map, | 406 | /* Must be called when no change can occur to cpu_present_map, |
384 | * i.e. during cpu online or offline. | 407 | * i.e. during cpu online or offline. |
385 | */ | 408 | */ |