diff options
| author | Will Deacon <will.deacon@arm.com> | 2012-01-20 11:01:12 (GMT) |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2012-01-23 10:20:05 (GMT) |
| commit | eb50439b92b6298bf209a982f295ba9c0f7cb30b (patch) | |
| tree | 8678f4221e4a40907d9781753a8b95c96bbfded6 /arch/arm/kernel | |
| parent | a092f2b15399bb4d1aa4e83cffe775f0c946f323 (diff) | |
| download | linux-eb50439b92b6298bf209a982f295ba9c0f7cb30b.tar.xz | |
ARM: 7293/1: logical_cpu_map: decouple CPU mapping from SMP
It turns out that the logical CPU mapping is useful even when !CONFIG_SMP
for manipulation of devices like interrupt and power controllers when
running a UP kernel on a CPU other than 0. This can happen when kexecing
a UP image from an SMP kernel.
In the future, multi-cluster systems running AMP configurations will
require something similar for mapping cluster IDs, so it makes sense to
decouple this logic in preparation for this support.
Acked-by: Yang Bai <hamo.by@gmail.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reported-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/kernel')
| -rw-r--r-- | arch/arm/kernel/setup.c | 14 | ||||
| -rw-r--r-- | arch/arm/kernel/smp.c | 14 |
2 files changed, 14 insertions, 14 deletions
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index ab70c91..a255c39 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -426,6 +426,20 @@ void cpu_init(void) : "r14"); } +int __cpu_logical_map[NR_CPUS]; + +void __init smp_setup_processor_id(void) +{ + int i; + u32 cpu = is_smp() ? read_cpuid_mpidr() & 0xff : 0; + + cpu_logical_map(0) = cpu; + for (i = 1; i < NR_CPUS; ++i) + cpu_logical_map(i) = i == cpu ? 0 : i; + + printk(KERN_INFO "Booting Linux on physical CPU %d\n", cpu); +} + static void __init setup_processor(void) { struct proc_info_list *list; diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 26cdc49..cdeb727 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -233,20 +233,6 @@ void __ref cpu_die(void) } #endif /* CONFIG_HOTPLUG_CPU */ -int __cpu_logical_map[NR_CPUS]; - -void __init smp_setup_processor_id(void) -{ - int i; - u32 cpu = is_smp() ? read_cpuid_mpidr() & 0xff : 0; - - cpu_logical_map(0) = cpu; - for (i = 1; i < NR_CPUS; ++i) - cpu_logical_map(i) = i == cpu ? 0 : i; - - printk(KERN_INFO "Booting Linux on physical CPU %d\n", cpu); -} - /* * Called by both boot and secondaries to move global data into * per-processor storage. |