vppinfra - ARM: cycle count 64bits register is only available on ARMv8

Change-Id: I7d622e591020a482af68667f4d1ed2056258d2c8
Signed-off-by: Christophe Fontaine <christophe.fontaine@qosmos.com>

diff --git a/vppinfra/vppinfra/time.h b/vppinfra/vppinfra/time.h
index 29398f3..ffafaf7 100644 (file)
--- a/vppinfra/vppinfra/time.h
+++ b/vppinfra/vppinfra/time.h
@@ -113,13 +113,20 @@ always_inline u64 clib_cpu_time_now (void)
 }
 
 #elif defined (__arm__)
-#if defined(__ARM_ARCH_7A__)
-always_inline u64 clib_cpu_time_now (void)
+#if defined(__ARM_ARCH_8A__)
+always_inline u64 clib_cpu_time_now (void) /* We may run arm64 in aarch32 mode, to leverage 64bit counter */
 {
   u64 tsc;
   asm volatile("mrrc p15, 0, %Q0, %R0, c9" : "=r" (tsc));
   return tsc;
 }
+#elif defined(__ARM_ARCH_7A__)
+always_inline u64 clib_cpu_time_now (void)
+{
+  u32 tsc;
+  asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (tsc));
+  return (u64)tsc;
+}
 #else
 always_inline u64 clib_cpu_time_now (void)
 {