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

Nicolas Pitre nicolas.pitre at linaro.org
Sun Nov 18 22:08:20 EST 2012


On Thu, 15 Nov 2012, Lorenzo Pieralisi wrote:

> 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>

Acked-by: Nicolas Pitre <nico at linaro.org>

> ---
>  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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