From 2f899e03a94cac4b092e4c013c6afda73178cc9f Mon Sep 17 00:00:00 2001 From: Vadim Bendebury Date: Tue, 23 Oct 2012 18:04:32 +0000 Subject: [PATCH] x86: Add function to read time stamp counter Put this function in the u-boot-x86.h header file. We could instead create timer.h perhaps. We support setting a base time, and reading the time relative to this base. Signed-off-by: Vadim Bendebury Signed-off-by: Stefan Reinauer Signed-off-by: Simon Glass --- arch/x86/include/asm/u-boot-x86.h | 12 ++++++++++++ arch/x86/lib/timer.c | 17 +++++++++++++++++ 2 files changed, 29 insertions(+) diff --git a/arch/x86/include/asm/u-boot-x86.h b/arch/x86/include/asm/u-boot-x86.h index a4a5ae05d1..11be5c35b5 100644 --- a/arch/x86/include/asm/u-boot-x86.h +++ b/arch/x86/include/asm/u-boot-x86.h @@ -68,4 +68,16 @@ int video_init(void); void board_init_f_r_trampoline(ulong) __attribute__ ((noreturn)); void board_init_f_r(void) __attribute__ ((noreturn)); +/* Read the time stamp counter */ +static inline uint64_t rdtsc(void) +{ + uint32_t high, low; + __asm__ __volatile__("rdtsc" : "=a" (low), "=d" (high)); + return (((uint64_t)high) << 32) | low; +} + +/* board/... */ +void timer_set_tsc_base(uint64_t new_base); +uint64_t timer_get_tsc(void); + #endif /* _U_BOOT_I386_H_ */ diff --git a/arch/x86/lib/timer.c b/arch/x86/lib/timer.c index fd7032e92c..a13424b3e3 100644 --- a/arch/x86/lib/timer.c +++ b/arch/x86/lib/timer.c @@ -37,6 +37,7 @@ struct timer_isr_function { static struct timer_isr_function *first_timer_isr; static unsigned long system_ticks; +static uint64_t base_value; /* * register_timer_isr() allows multiple architecture and board specific @@ -98,3 +99,19 @@ ulong get_timer(ulong base) { return system_ticks - base; } + +void timer_set_tsc_base(uint64_t new_base) +{ + base_value = new_base; +} + +uint64_t timer_get_tsc(void) +{ + uint64_t time_now; + + time_now = rdtsc(); + if (!base_value) + base_value = time_now; + + return time_now - base_value; +} -- 2.39.5