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-rw-r--r--gcell/src/lib/runtime/spu/gc_delay.c58
1 files changed, 58 insertions, 0 deletions
diff --git a/gcell/src/lib/runtime/spu/gc_delay.c b/gcell/src/lib/runtime/spu/gc_delay.c
new file mode 100644
index 000000000..21ee587f8
--- /dev/null
+++ b/gcell/src/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 "gc_delay.h"
+#include <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
+ }
+}
+