linux/arch/arm/include/asm/smp_plat.h
Will Deacon eb50439b92 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>
2012-01-23 10:20:05 +00:00

53 lines
978 B
C

/*
* ARM specific SMP header, this contains our implementation
* details.
*/
#ifndef __ASMARM_SMP_PLAT_H
#define __ASMARM_SMP_PLAT_H
#include <asm/cputype.h>
/*
* Return true if we are running on a SMP platform
*/
static inline bool is_smp(void)
{
#ifndef CONFIG_SMP
return false;
#elif defined(CONFIG_SMP_ON_UP)
extern unsigned int smp_on_up;
return !!smp_on_up;
#else
return true;
#endif
}
/* all SMP configurations have the extended CPUID registers */
static inline int tlb_ops_need_broadcast(void)
{
if (!is_smp())
return 0;
return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 2;
}
#if !defined(CONFIG_SMP) || __LINUX_ARM_ARCH__ >= 7
#define cache_ops_need_broadcast() 0
#else
static inline int cache_ops_need_broadcast(void)
{
if (!is_smp())
return 0;
return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 1;
}
#endif
/*
* Logical CPU mapping.
*/
extern int __cpu_logical_map[];
#define cpu_logical_map(cpu) __cpu_logical_map[cpu]
#endif