ARC: breakout aux handling into a separate header

ARC timers use aux registers for programming and this paves way for
moving ARC timer drivers into drivers/clocksource

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

1 files changed, 63 insertions, 0 deletions

diff --git a/include/soc/arc/aux.h b/include/soc/arc/aux.h
new file mode 100644
index 000000000000..8c3fb13e0452
--- /dev/null
+++ b/include/soc/arc/aux.h
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2016-2017 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#ifndef __SOC_ARC_AUX_H__
+#define __SOC_ARC_AUX_H__
+
+#ifdef CONFIG_ARC
+
+#define read_aux_reg(r)         __builtin_arc_lr(r)
+
+/* gcc builtin sr needs reg param to be long immediate */
+#define write_aux_reg(r, v)     __builtin_arc_sr((unsigned int)(v), r)
+
+#else   /* !CONFIG_ARC */
+
+static inline int read_aux_reg(u32 r)
+{
+        return 0;
+}
+
+/*
+ * function helps elide unused variable warning
+ * see: http://lists.infradead.org/pipermail/linux-snps-arc/2016-November/001748.html
+ */
+static inline void write_aux_reg(u32 r, u32 v)
+{
+        ;
+}
+
+#endif
+
+#define READ_BCR(reg, into)                             \
+{                                                       \
+        unsigned int tmp;                               \
+        tmp = read_aux_reg(reg);                        \
+        if (sizeof(tmp) == sizeof(into)) {              \
+                into = *((typeof(into) *)&tmp);         \
+        } else {                                        \
+                extern void bogus_undefined(void);      \
+                bogus_undefined();                      \
+        }                                               \
+}
+
+#define WRITE_AUX(reg, into)                            \
+{                                                       \
+        unsigned int tmp;                               \
+        if (sizeof(tmp) == sizeof(into)) {              \
+                tmp = (*(unsigned int *)&(into));       \
+                write_aux_reg(reg, tmp);                \
+        } else  {                                       \
+                extern void bogus_undefined(void);      \
+                bogus_undefined();                      \
+        }                                               \
+}
+
+
+#endif