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>

arch/arc/include/asm/arcregs.h

@@ -112,90 +112,7 @@
 
 #ifndef __ASSEMBLY__
 
-/*
+#include <soc/arc/aux.h>
- ******************************************************************
- *      Inline ASM macros to read/write AUX Regs
- *      Essentially invocation of lr/sr insns from "C"
- */
-
-#if 1
-
-#define read_aux_reg(reg)	__builtin_arc_lr(reg)
-
-/* gcc builtin sr needs reg param to be long immediate */
-#define write_aux_reg(reg_immed, val)		\
-		__builtin_arc_sr((unsigned int)(val), reg_immed)
-
-#else
-
-#define read_aux_reg(reg)		\
-({					\
-	unsigned int __ret;		\
-	__asm__ __volatile__(		\
-	"	lr    %0, [%1]"		\
-	: "=r"(__ret)			\
-	: "i"(reg));			\
-	__ret;				\
-})
-
-/*
- * Aux Reg address is specified as long immediate by caller
- * e.g.
- *    write_aux_reg(0x69, some_val);
- * This generates tightest code.
- */
-#define write_aux_reg(reg_imm, val)	\
-({					\
-	__asm__ __volatile__(		\
-	"	sr   %0, [%1]	\n"	\
-	:				\
-	: "ir"(val), "i"(reg_imm));	\
-})
-
-/*
- * Aux Reg address is specified in a variable
- *  * e.g.
- *      reg_num = 0x69
- *      write_aux_reg2(reg_num, some_val);
- * This has to generate glue code to load the reg num from
- *  memory to a reg hence not recommended.
- */
-#define write_aux_reg2(reg_in_var, val)		\
-({						\
-	unsigned int tmp;			\
-						\
-	__asm__ __volatile__(			\
-	"	ld   %0, [%2]	\n\t"		\
-	"	sr   %1, [%0]	\n\t"		\
-	: "=&r"(tmp)				\
-	: "r"(val), "memory"(&reg_in_var));	\
-})
-
-#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();			\
-	}						\
-}
 
 /* Helpers */
 #define TO_KB(bytes)		((bytes) >> 10)

arch/arc/include/asm/mcip.h

@@ -13,7 +13,7 @@
 
 #ifdef CONFIG_ISA_ARCV2
 
-#include <asm/arcregs.h>
+#include <soc/arc/aux.h>
 
 #define ARC_REG_MCIP_BCR	0x0d0
 #define ARC_REG_MCIP_CMD	0x600

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