arm64: smccc: replace custom COUNT_ARGS() & CONCATENATE() implementations

Replace custom implementation of the macros from args.h.

Link: https://lkml.kernel.org/r/20230718211147.18647-4-andriy.shevchenko@linux.intel.comSigned-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: Daniel Latypov <dlatypov@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Gow <davidgow@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

include/linux/arm-smccc.h

@@ -5,6 +5,7 @@
 #ifndef __LINUX_ARM_SMCCC_H
 #define __LINUX_ARM_SMCCC_H
 
+#include <linux/args.h>
 #include <linux/init.h>
 #include <uapi/linux/const.h>
 
@@ -413,31 +414,26 @@ asmlinkage void __arm_smccc_hvc(unsigned long a0, unsigned long a1,
 
 #endif
 
-#define ___count_args(_0, _1, _2, _3, _4, _5, _6, _7, _8, x, ...) x
+#define __constraint_read_2	"r" (arg0)
+#define __constraint_read_3	__constraint_read_2, "r" (arg1)
+#define __constraint_read_4	__constraint_read_3, "r" (arg2)
+#define __constraint_read_5	__constraint_read_4, "r" (arg3)
+#define __constraint_read_6	__constraint_read_5, "r" (arg4)
+#define __constraint_read_7	__constraint_read_6, "r" (arg5)
+#define __constraint_read_8	__constraint_read_7, "r" (arg6)
+#define __constraint_read_9	__constraint_read_8, "r" (arg7)
 
-#define __count_args(...)						\
-	___count_args(__VA_ARGS__, 7, 6, 5, 4, 3, 2, 1, 0)
-
-#define __constraint_read_0	"r" (arg0)
-#define __constraint_read_1	__constraint_read_0, "r" (arg1)
-#define __constraint_read_2	__constraint_read_1, "r" (arg2)
-#define __constraint_read_3	__constraint_read_2, "r" (arg3)
-#define __constraint_read_4	__constraint_read_3, "r" (arg4)
-#define __constraint_read_5	__constraint_read_4, "r" (arg5)
-#define __constraint_read_6	__constraint_read_5, "r" (arg6)
-#define __constraint_read_7	__constraint_read_6, "r" (arg7)
-
-#define __declare_arg_0(a0, res)					\
+#define __declare_arg_2(a0, res)					\
 	struct arm_smccc_res   *___res = res;				\
 	register unsigned long arg0 asm("r0") = (u32)a0
 
-#define __declare_arg_1(a0, a1, res)					\
+#define __declare_arg_3(a0, a1, res)					\
 	typeof(a1) __a1 = a1;						\
 	struct arm_smccc_res   *___res = res;				\
 	register unsigned long arg0 asm("r0") = (u32)a0;			\
 	register typeof(a1) arg1 asm("r1") = __a1
 
-#define __declare_arg_2(a0, a1, a2, res)				\
+#define __declare_arg_4(a0, a1, a2, res)				\
 	typeof(a1) __a1 = a1;						\
 	typeof(a2) __a2 = a2;						\
 	struct arm_smccc_res   *___res = res;				\
@@ -445,7 +441,7 @@ asmlinkage void __arm_smccc_hvc(unsigned long a0, unsigned long a1,
 	register typeof(a1) arg1 asm("r1") = __a1;			\
 	register typeof(a2) arg2 asm("r2") = __a2
 
-#define __declare_arg_3(a0, a1, a2, a3, res)				\
+#define __declare_arg_5(a0, a1, a2, a3, res)				\
 	typeof(a1) __a1 = a1;						\
 	typeof(a2) __a2 = a2;						\
 	typeof(a3) __a3 = a3;						\
@@ -455,34 +451,26 @@ asmlinkage void __arm_smccc_hvc(unsigned long a0, unsigned long a1,
 	register typeof(a2) arg2 asm("r2") = __a2;			\
 	register typeof(a3) arg3 asm("r3") = __a3
 
-#define __declare_arg_4(a0, a1, a2, a3, a4, res)			\
+#define __declare_arg_6(a0, a1, a2, a3, a4, res)			\
 	typeof(a4) __a4 = a4;						\
-	__declare_arg_3(a0, a1, a2, a3, res);				\
+	__declare_arg_5(a0, a1, a2, a3, res);				\
 	register typeof(a4) arg4 asm("r4") = __a4
 
-#define __declare_arg_5(a0, a1, a2, a3, a4, a5, res)			\
+#define __declare_arg_7(a0, a1, a2, a3, a4, a5, res)			\
 	typeof(a5) __a5 = a5;						\
-	__declare_arg_4(a0, a1, a2, a3, a4, res);			\
+	__declare_arg_6(a0, a1, a2, a3, a4, res);			\
 	register typeof(a5) arg5 asm("r5") = __a5
 
-#define __declare_arg_6(a0, a1, a2, a3, a4, a5, a6, res)		\
+#define __declare_arg_8(a0, a1, a2, a3, a4, a5, a6, res)		\
 	typeof(a6) __a6 = a6;						\
-	__declare_arg_5(a0, a1, a2, a3, a4, a5, res);			\
+	__declare_arg_7(a0, a1, a2, a3, a4, a5, res);			\
 	register typeof(a6) arg6 asm("r6") = __a6
 
-#define __declare_arg_7(a0, a1, a2, a3, a4, a5, a6, a7, res)		\
+#define __declare_arg_9(a0, a1, a2, a3, a4, a5, a6, a7, res)		\
 	typeof(a7) __a7 = a7;						\
-	__declare_arg_6(a0, a1, a2, a3, a4, a5, a6, res);		\
+	__declare_arg_8(a0, a1, a2, a3, a4, a5, a6, res);		\
 	register typeof(a7) arg7 asm("r7") = __a7
 
-#define ___declare_args(count, ...) __declare_arg_ ## count(__VA_ARGS__)
-#define __declare_args(count, ...)  ___declare_args(count, __VA_ARGS__)
-
-#define ___constraints(count)						\
-	: __constraint_read_ ## count					\
-	: smccc_sve_clobbers "memory"
-#define __constraints(count)	___constraints(count)
-
 /*
  * We have an output list that is not necessarily used, and GCC feels
  * entitled to optimise the whole sequence away. "volatile" is what
@@ -494,11 +482,14 @@ asmlinkage void __arm_smccc_hvc(unsigned long a0, unsigned long a1,
 		register unsigned long r1 asm("r1");			\
 		register unsigned long r2 asm("r2");			\
 		register unsigned long r3 asm("r3"); 			\
-		__declare_args(__count_args(__VA_ARGS__), __VA_ARGS__);	\
+		CONCATENATE(__declare_arg_,				\
+			    COUNT_ARGS(__VA_ARGS__))(__VA_ARGS__);	\
 		asm volatile(SMCCC_SVE_CHECK				\
 			     inst "\n" :				\
 			     "=r" (r0), "=r" (r1), "=r" (r2), "=r" (r3)	\
-			     __constraints(__count_args(__VA_ARGS__)));	\
+			     : CONCATENATE(__constraint_read_,		\
+					   COUNT_ARGS(__VA_ARGS__))	\
+			     : smccc_sve_clobbers "memory");		\
 		if (___res)						\
 			*___res = (typeof(*___res)){r0, r1, r2, r3};	\
 	} while (0)
@@ -542,8 +533,12 @@ asmlinkage void __arm_smccc_hvc(unsigned long a0, unsigned long a1,
  */
 #define __fail_smccc_1_1(...)						\
 	do {								\
-		__declare_args(__count_args(__VA_ARGS__), __VA_ARGS__);	\
-		asm ("" : __constraints(__count_args(__VA_ARGS__)));	\
+		CONCATENATE(__declare_arg_,				\
+			    COUNT_ARGS(__VA_ARGS__))(__VA_ARGS__);	\
+		asm ("" :						\
+		     : CONCATENATE(__constraint_read_,			\
+				   COUNT_ARGS(__VA_ARGS__))		\
+		     : smccc_sve_clobbers "memory");			\
 		if (___res)						\
 			___res->a0 = SMCCC_RET_NOT_SUPPORTED;		\
 	} while (0)