[RFC PATCH v4 02/18] ARM: kernel: fix __cpu_logical_map default initialization

[Nicolas Pitre]

On Fri, 17 May 2013, Lorenzo Pieralisi wrote:

> The __cpu_logical_map array is statically initialized to 0, which is a valid
> MPIDR value. To prevent issues with the current implementation, this patch
> defines an MPIDR_INVALID value, and statically initializes the
> __cpu_logical_map[] array to it. Entries in the arm_dt_init_cpu_maps()
> tmp_map array used to stash DT reg properties while parsing DT are initialized
> with the MPIDR_INVALID value as well for consistency.
> 
> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
> CC: Will Deacon <will.deacon at arm.com>

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


> ---
>  arch/arm/include/asm/cputype.h  | 2 ++
>  arch/arm/include/asm/smp_plat.h | 2 +-
>  arch/arm/kernel/devtree.c       | 2 +-
>  arch/arm/kernel/setup.c         | 2 +-
>  4 files changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h
> index 7652712..dba62cb 100644
> --- a/arch/arm/include/asm/cputype.h
> +++ b/arch/arm/include/asm/cputype.h
> @@ -32,6 +32,8 @@
>  
>  #define MPIDR_HWID_BITMASK 0xFFFFFF
>  
> +#define MPIDR_INVALID (~MPIDR_HWID_BITMASK)
> +
>  #define MPIDR_LEVEL_BITS 8
>  #define MPIDR_LEVEL_MASK ((1 << MPIDR_LEVEL_BITS) - 1)
>  
> diff --git a/arch/arm/include/asm/smp_plat.h b/arch/arm/include/asm/smp_plat.h
> index aaa61b6..e789832 100644
> --- a/arch/arm/include/asm/smp_plat.h
> +++ b/arch/arm/include/asm/smp_plat.h
> @@ -49,7 +49,7 @@ static inline int cache_ops_need_broadcast(void)
>  /*
>   * Logical CPU mapping.
>   */
> -extern int __cpu_logical_map[];
> +extern u32 __cpu_logical_map[];
>  #define cpu_logical_map(cpu)	__cpu_logical_map[cpu]
>  /*
>   * Retrieve logical cpu index corresponding to a given MPIDR[23:0]
> diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c
> index 904cad5..0905502 100644
> --- a/arch/arm/kernel/devtree.c
> +++ b/arch/arm/kernel/devtree.c
> @@ -82,7 +82,7 @@ void __init arm_dt_init_cpu_maps(void)
>  	u32 i, j, cpuidx = 1;
>  	u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
>  
> -	u32 tmp_map[NR_CPUS] = { [0 ... NR_CPUS-1] = UINT_MAX };
> +	u32 tmp_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
>  	bool bootcpu_valid = false;
>  	cpus = of_find_node_by_path("/cpus");
>  
> diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
> index 6ae71b7..eeac924 100644
> --- a/arch/arm/kernel/setup.c
> +++ b/arch/arm/kernel/setup.c
> @@ -457,7 +457,7 @@ void notrace cpu_init(void)
>  	    : "r14");
>  }
>  
> -int __cpu_logical_map[NR_CPUS];
> +u32 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
>  
>  void __init smp_setup_processor_id(void)
>  {
> -- 
> 1.8.2.2
> 
> 
> _______________________________________________
> devicetree-discuss mailing list
> devicetree-discuss at lists.ozlabs.org
> https://lists.ozlabs.org/listinfo/devicetree-discuss
>