1 files changed, 83 insertions, 0 deletions

diff --git a/nacl/cpucycles/celllinux.c b/nacl/cpucycles/celllinux.c
new file mode 100644
index 00000000..83a0c38a
--- /dev/null
+++ b/nacl/cpucycles/celllinux.c
@@ -0,0 +1,83 @@
+#include <time.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <spu_mfcio.h>
+
+static long myround(double u)
+{
+  long result = u;
+  while (result + 0.5 < u) result += 1;
+  while (result - 0.5 > u) result -= 1;
+  return result;
+}
+
+static long long microseconds(void)
+{
+  struct timeval t;
+  gettimeofday(&t,(struct timezone *) 0);
+  return t.tv_sec * (long long) 1000000 + t.tv_usec;
+}
+
+static long long timebase(void)
+{
+  unsigned long long result;
+  result = -spu_read_decrementer();
+  return 0xffffffff & result;
+}
+
+static double cpufrequency = 0;
+static long tbcycles = 0;
+
+static double guesstbcycles(void)
+{
+  long long tb0; long long us0;
+  long long tb1; long long us1;
+
+  tb0 = timebase();
+  us0 = microseconds();
+  do {
+    tb1 = timebase();
+    us1 = microseconds();
+  } while (us1 - us0 < 10000 || tb1 - tb0 < 1000);
+  if (tb1 <= tb0) return 0;
+  tb1 -= tb0;
+  us1 -= us0;
+  return (cpufrequency * 0.000001 * (double) us1) / (double) tb1;
+}
+
+static void init(void)
+{
+  int loop;
+  double guess1;
+  double guess2;
+
+  spu_write_decrementer(0xffffffff);
+
+  cpufrequency = 3192000000.0;
+
+  for (loop = 0;loop < 100;++loop) {
+    guess1 = guesstbcycles();
+    guess2 = guesstbcycles();
+    tbcycles = myround(guess1);
+    if (guess1 - tbcycles > 0.1) continue;
+    if (tbcycles - guess1 > 0.1) continue;
+    if (guess2 - tbcycles > 0.1) continue;
+    if (tbcycles - guess2 > 0.1) continue;
+    return;
+  }
+  tbcycles = 0;
+}
+
+long long cpucycles_celllinux(void)
+{
+  if (!tbcycles) init();
+  return timebase() * tbcycles;
+}
+
+long long cpucycles_celllinux_persecond(void)
+{
+  if (!tbcycles) init();
+  return cpufrequency;
+}