From c0379aec241c78fe07074fa7e63a5009a4e7944a Mon Sep 17 00:00:00 2001 From: Brian Brooks Date: Tue, 9 Jan 2018 16:39:07 -0600 Subject: Arm system counter cleanup Add some description and cleanup code that uses Arm system counter. Change-Id: Ie1fe00e3e4b5d98867617b7b0184ac526e333c53 Signed-off-by: Brian Brooks --- src/vppinfra/time.h | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-) (limited to 'src/vppinfra/time.h') diff --git a/src/vppinfra/time.h b/src/vppinfra/time.h index 288922d8a83..ead4b7d8ea4 100644 --- a/src/vppinfra/time.h +++ b/src/vppinfra/time.h @@ -114,6 +114,16 @@ clib_cpu_time_now (void) return (u64) lo + ((u64) hi2 << (u64) 32); } +#elif defined (__aarch64__) +always_inline u64 +clib_cpu_time_now (void) +{ + u64 vct; + /* User access to cntvct_el0 is enabled in Linux kernel since 3.12. */ + asm volatile ("mrs %0, cntvct_el0":"=r" (vct)); + return vct; +} + #elif defined (__arm__) #if defined(__ARM_ARCH_8A__) always_inline u64 @@ -164,18 +174,6 @@ clib_cpu_time_now (void) return ((u64) h << 32) | l; } -#elif defined (__aarch64__) -always_inline u64 -clib_cpu_time_now (void) -{ - u64 tsc; - - /* Works on Cavium ThunderX. Other platforms: YMMV */ - asm volatile ("mrs %0, cntvct_el0":"=r" (tsc)); - - return tsc; -} - #else #error "don't know how to read CPU time stamp" -- cgit 1.2.3-korg