Imported Upstream version 3.2.2

[debian/gnuradio] / gcell / lib / runtime / spu / gc_delay.c

diff --git a/gcell/lib/runtime/spu/gc_delay.c b/gcell/lib/runtime/spu/gc_delay.c
new file mode 100644 (file)
index 0000000..4d58935
--- /dev/null
+++ b/gcell/lib/runtime/spu/gc_delay.c
@@ -0,0 +1,58 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2007 Free Software Foundation, Inc.
+ * 
+ * This file is part of GNU Radio
+ * 
+ * GNU Radio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3, or (at your option)
+ * any later version.
+ * 
+ * GNU Radio is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <gcell/spu/gc_delay.h>
+#include <gcell/compiler.h>
+
+inline static void
+gc_udelay_1us(void)
+{
+  unsigned int i = 158;
+
+  do {  // 20 clocks per iteration of the loop
+    asm ("nop $127; nop $127; nop $127; nop $127; nop $127");
+    asm ("nop $127; nop $127; nop $127; nop $127; nop $127");
+    asm ("nop $127; nop $127; nop $127; nop $127; nop $127");
+    asm ("nop $127; nop $127");
+  } while(--i != 0);
+}
+
+void
+gc_udelay(unsigned int usecs)
+{
+  unsigned int i;
+  for (i = 0; i < usecs; i++)
+    gc_udelay_1us();
+}
+
+void
+gc_cdelay(unsigned int cpu_cycles)
+{
+  if (cpu_cycles < 40) // roughly the amount of overhead
+    return;
+  
+  cpu_cycles >>= 2;    // about 4 cycles / loop
+
+  while (cpu_cycles-- != 0){
+    asm ("nop $127");  // keeps compiler from removing the loop
+  }
+}
+