[PATCH] RISC-V: Add support fo the zihintpause extension

[Palmer Dabbelt <palmer@rivosinc.com>]

This was recently added to binutils and with any luck will soon be in
Linux, without it sparse will fail when trying to build new kernels on
systems with new toolchains.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
I re-indented the other extensions to match, and this one is on top of
the Zicbom patch as I figured that'd be easier.
---
 target-riscv.c | 50 +++++++++++++++++++++++++++-----------------------
 1 file changed, 27 insertions(+), 23 deletions(-)

diff --git a/target-riscv.c b/target-riscv.c
index db0f7e57..23d28d0e 100644
--- a/target-riscv.c
+++ b/target-riscv.c
@@ -5,21 +5,22 @@
 #include <string.h>
 #include <stdio.h>
 
-#define RISCV_32BIT	(1 << 0)
-#define RISCV_64BIT	(1 << 1)
-#define RISCV_MUL	(1 << 2)
-#define RISCV_DIV	(1 << 3)
-#define RISCV_ATOMIC	(1 << 4)
-#define RISCV_FLOAT	(1 << 5)
-#define RISCV_DOUBLE	(1 << 6)
-#define RISCV_FDIV	(1 << 7)
-#define RISCV_COMP	(1 << 8)
-#define RISCV_EMBD	(1 << 9)
-#define RISCV_FPU	(RISCV_FLOAT|RISCV_DOUBLE|RISCV_FDIV)
-#define RISCV_GENERIC	(RISCV_MUL|RISCV_DIV|RISCV_ATOMIC|RISCV_FPU)
-#define RISCV_ZICSR	(1 << 10)
-#define RISCV_ZIFENCEI	(1 << 11)
-#define RISCV_ZICBOM	(1 << 12)
+#define RISCV_32BIT		(1 << 0)
+#define RISCV_64BIT		(1 << 1)
+#define RISCV_MUL		(1 << 2)
+#define RISCV_DIV		(1 << 3)
+#define RISCV_ATOMIC		(1 << 4)
+#define RISCV_FLOAT		(1 << 5)
+#define RISCV_DOUBLE		(1 << 6)
+#define RISCV_FDIV		(1 << 7)
+#define RISCV_COMP		(1 << 8)
+#define RISCV_EMBD		(1 << 9)
+#define RISCV_FPU		(RISCV_FLOAT|RISCV_DOUBLE|RISCV_FDIV)
+#define RISCV_GENERIC		(RISCV_MUL|RISCV_DIV|RISCV_ATOMIC|RISCV_FPU)
+#define RISCV_ZICSR		(1 << 10)
+#define RISCV_ZIFENCEI		(1 << 11)
+#define RISCV_ZICBOM		(1 << 12)
+#define RISCV_ZIHINTPAUSE	(1 << 13)
 
 static unsigned int riscv_flags;
 
@@ -35,14 +36,15 @@ static void parse_march_riscv(const char *arg)
 		{ "rv64i",	RISCV_64BIT },
 		{ "rv64g",	RISCV_64BIT|RISCV_GENERIC },
 	}, extensions[] = {
-		{ "m",		RISCV_MUL|RISCV_DIV },
-		{ "a",		RISCV_ATOMIC },
-		{ "f",		RISCV_FLOAT|RISCV_FDIV|RISCV_ZICSR },
-		{ "d",		RISCV_DOUBLE|RISCV_FDIV|RISCV_ZICSR },
-		{ "c",		RISCV_COMP },
-		{ "_zicsr",	RISCV_ZICSR },
-		{ "_zifencei",	RISCV_ZIFENCEI },
-		{ "_zicbom",	RISCV_ZICBOM },
+		{ "m",			RISCV_MUL|RISCV_DIV },
+		{ "a",			RISCV_ATOMIC },
+		{ "f",			RISCV_FLOAT|RISCV_FDIV|RISCV_ZICSR },
+		{ "d",			RISCV_DOUBLE|RISCV_FDIV|RISCV_ZICSR },
+		{ "c",			RISCV_COMP },
+		{ "_zicsr",		RISCV_ZICSR },
+		{ "_zifencei",		RISCV_ZIFENCEI },
+		{ "_zicbom",		RISCV_ZICBOM },
+		{ "_zihintpause",	RISCV_ZIHINTPAUSE },
 	};
 	int i;
 
@@ -135,6 +137,8 @@ static void predefine_riscv(const struct target *self)
 		predefine("__riscv_zifencei", 1, "1");
 	if (riscv_flags & RISCV_ZICBOM)
 		predefine("__riscv_zicbom", 1, "1");
+	if (riscv_flags & RISCV_ZIHINTPAUSE)
+		predefine("__riscv_zihintpause", 1, "1");
 
 	if (cmodel)
 		predefine_strong("__riscv_cmodel_%s", cmodel);
-- 
2.34.1