 7f124aaf01
			
		
	
	
	7f124aaf01
	
	
	
		
			
			In ARM SMP systems the MPIDR register ([23:0] bits) is used to uniquely identify CPUs. In order to retrieve the logical CPU index corresponding to a given MPIDR value and guarantee a consistent translation throughout the kernel, this patch adds a look-up based on the MPIDR[23:0] so that kernel subsystems can use it whenever the logical cpu index corresponding to a given MPIDR value is needed. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Nicolas Pitre <nico@linaro.org>
		
			
				
	
	
		
			69 lines
		
	
	
	
		
			1.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			69 lines
		
	
	
	
		
			1.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * ARM specific SMP header, this contains our implementation
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|  * details.
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|  */
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| #ifndef __ASMARM_SMP_PLAT_H
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| #define __ASMARM_SMP_PLAT_H
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| 
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| #include <linux/cpumask.h>
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| #include <linux/err.h>
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| 
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| #include <asm/cputype.h>
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| 
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| /*
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|  * Return true if we are running on a SMP platform
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|  */
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| static inline bool is_smp(void)
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| {
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| #ifndef CONFIG_SMP
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| 	return false;
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| #elif defined(CONFIG_SMP_ON_UP)
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| 	extern unsigned int smp_on_up;
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| 	return !!smp_on_up;
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| #else
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| 	return true;
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| #endif
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| }
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| 
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| /* all SMP configurations have the extended CPUID registers */
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| static inline int tlb_ops_need_broadcast(void)
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| {
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| 	if (!is_smp())
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| 		return 0;
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| 
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| 	return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 2;
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| }
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| 
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| #if !defined(CONFIG_SMP) || __LINUX_ARM_ARCH__ >= 7
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| #define cache_ops_need_broadcast()	0
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| #else
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| static inline int cache_ops_need_broadcast(void)
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| {
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| 	if (!is_smp())
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| 		return 0;
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| 
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| 	return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 1;
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| }
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| #endif
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| 
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| /*
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|  * Logical CPU mapping.
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|  */
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| extern int __cpu_logical_map[];
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| #define cpu_logical_map(cpu)	__cpu_logical_map[cpu]
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| /*
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|  * Retrieve logical cpu index corresponding to a given MPIDR[23:0]
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|  *  - mpidr: MPIDR[23:0] to be used for the look-up
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|  *
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|  * Returns the cpu logical index or -EINVAL on look-up error
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|  */
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| static inline int get_logical_index(u32 mpidr)
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| {
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| 	int cpu;
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| 	for (cpu = 0; cpu < nr_cpu_ids; cpu++)
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| 		if (cpu_logical_map(cpu) == mpidr)
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| 			return cpu;
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| 	return -EINVAL;
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| }
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| 
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| #endif
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