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-rw-r--r--include/asm-blackfin/delay.h44
1 files changed, 44 insertions, 0 deletions
diff --git a/include/asm-blackfin/delay.h b/include/asm-blackfin/delay.h
new file mode 100644
index 000000000000..52e7a10d7ff8
--- /dev/null
+++ b/include/asm-blackfin/delay.h
@@ -0,0 +1,44 @@
+#ifndef _BLACKFIN_DELAY_H
+#define _BLACKFIN_DELAY_H
+
+static inline void __delay(unsigned long loops)
+{
+
+/* FIXME: Currently the assembler doesn't recognize Loop Register Clobbers,
+ uncomment this as soon those are implemented */
+/*
+ __asm__ __volatile__ ( "\t LSETUP (1f,1f) LC0= %0\n\t"
+ "1:\t NOP;\n\t"
+ : :"a" (loops)
+ : "LT0","LB0","LC0");
+
+*/
+
+ __asm__ __volatile__("[--SP] = LC0;\n\t"
+ "[--SP] = LT0;\n\t"
+ "[--SP] = LB0;\n\t"
+ "LSETUP (1f,1f) LC0 = %0;\n\t"
+ "1:\t NOP;\n\t"
+ "LB0 = [SP++];\n\t"
+ "LT0 = [SP++];\n\t"
+ "LC0 = [SP++];\n"
+ :
+ :"a" (loops));
+}
+
+#include <linux/param.h> /* needed for HZ */
+
+/*
+ * Use only for very small delays ( < 1 msec). Should probably use a
+ * lookup table, really, as the multiplications take much too long with
+ * short delays. This is a "reasonable" implementation, though (and the
+ * first constant multiplications gets optimized away if the delay is
+ * a constant)
+ */
+static inline void udelay(unsigned long usecs)
+{
+ extern unsigned long loops_per_jiffy;
+ __delay(usecs * loops_per_jiffy / (1000000 / HZ));
+}
+
+#endif /* defined(_BLACKFIN_DELAY_H) */