From 923df96b9f31b7d08d8438ff9677326d9537accf Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Fri, 6 Jul 2012 15:46:45 +0100 Subject: ARM: 7451/1: arch timer: implement read_current_timer and get_cycles This patch implements read_current_timer using the architected timers when they are selected via CONFIG_ARM_ARCH_TIMER. If they are detected not to be usable at runtime, we return -ENXIO to the caller. Furthermore, if read_current_timer is exported then we can implement get_cycles in terms of it for use as both an entropy source and for implementing __udelay and friends. Tested-by: Shinya Kuribayashi Reviewed-by: Stephen Boyd Signed-off-by: Will Deacon Signed-off-by: Russell King --- arch/arm/include/asm/arch_timer.h | 3 +++ arch/arm/include/asm/timex.h | 10 ++++++---- 2 files changed, 9 insertions(+), 4 deletions(-) (limited to 'arch/arm/include/asm') diff --git a/arch/arm/include/asm/arch_timer.h b/arch/arm/include/asm/arch_timer.h index ed2e95d46e29..62e75475e57e 100644 --- a/arch/arm/include/asm/arch_timer.h +++ b/arch/arm/include/asm/arch_timer.h @@ -1,7 +1,10 @@ #ifndef __ASMARM_ARCH_TIMER_H #define __ASMARM_ARCH_TIMER_H +#include + #ifdef CONFIG_ARM_ARCH_TIMER +#define ARCH_HAS_READ_CURRENT_TIMER int arch_timer_of_register(void); int arch_timer_sched_clock_init(void); #else diff --git a/arch/arm/include/asm/timex.h b/arch/arm/include/asm/timex.h index 3be8de3adaba..ce119442277c 100644 --- a/arch/arm/include/asm/timex.h +++ b/arch/arm/include/asm/timex.h @@ -12,13 +12,15 @@ #ifndef _ASMARM_TIMEX_H #define _ASMARM_TIMEX_H +#include #include typedef unsigned long cycles_t; -static inline cycles_t get_cycles (void) -{ - return 0; -} +#ifdef ARCH_HAS_READ_CURRENT_TIMER +#define get_cycles() ({ cycles_t c; read_current_timer(&c) ? 0 : c; }) +#else +#define get_cycles() (0) +#endif #endif -- cgit v1.2.3