[PATCH v3 1/5] ARM: kernel: smp_setup_processor_id() updates

Lorenzo Pieralisi lorenzo.pieralisi at arm.com
Thu Nov 15 07:46:50 EST 2012


This patch applies some basic changes to the smp_setup_processor_id()
ARM implementation to make the code that builds cpu_logical_map more
uniform across the kernel.

The function now prints the full extent of the boot CPU MPIDR[23:0] and
initializes the cpu_logical_map for CPUs up to nr_cpu_ids.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
---
 arch/arm/kernel/setup.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index da1d1aa..d0df6c8 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -426,13 +426,14 @@ int __cpu_logical_map[NR_CPUS];
 void __init smp_setup_processor_id(void)
 {
 	int i;
-	u32 cpu = is_smp() ? read_cpuid_mpidr() & 0xff : 0;
+	u32 mpidr = is_smp() ? read_cpuid_mpidr() & 0xffffff : 0;
+	u32 cpu = mpidr & 0xff;
 
 	cpu_logical_map(0) = cpu;
-	for (i = 1; i < NR_CPUS; ++i)
+	for (i = 1; i < nr_cpu_ids; ++i)
 		cpu_logical_map(i) = i == cpu ? 0 : i;
 
-	printk(KERN_INFO "Booting Linux on physical CPU %d\n", cpu);
+	printk(KERN_INFO "Booting Linux on physical CPU 0x%x\n", mpidr);
 }
 
 static void __init setup_processor(void)
-- 
1.7.12





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