Changeset 3fa509b in mainline for kernel/arch/arm32/include/cycle.h

Timestamp:

2013-01-19T23:59:25Z (11 years ago)

Author:

Jan Vesely <jano.vesely@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

9eec7bc

Parents:

4b28c70

Message:

arm32, armv7: Add reading of performance cycles counter.

Fix comment about WFE.

File:

• kernel/arch/arm32/include/cycle.h (modified) (2 diffs)

kernel/arch/arm32/include/cycle.h

@@ -38 +38 @@
 
 #include <trace.h>
+#include <arch/cp15.h>
 
 /** Return count of CPU cycles.
@@ -48 +49 @@
 NO_TRACE static inline uint64_t get_cycle(void)
 {
+#ifdef PROCESSOR_ARCH_armv7_a
+        if ((ID_PFR1_read() & ID_PFR1_GEN_TIMER_EXT_MASK) ==
+            ID_PFR1_GEN_TIMER_EXT) {
+            uint32_t low = 0, high = 0;
+            asm volatile( "MRRC p15, 0, %[low], %[high], c14": [low]"=r"(low), [high]"=r"(high));
+           return ((uint64_t)high << 32) | low;
+        } else {
+                return PMCCNTR_read();
+        }
+#endif
         return 0;
 }