[PATCH] mips: only produce jr.hb if CPU support Release 2

[Yangyu Chen]

The jr.hb was introduced since MIPS32/64 Release 2. If this instruction
is executed on Release 1 CPU will lead to Reserved Instruction
Exception, so avoid this instruction when the CPU does not support
Release 2.

Signed-off-by: Yangyu Chen <cyy at cyyself.name>
---
 arch/mips/include/asm/system.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/mips/include/asm/system.h b/arch/mips/include/asm/system.h
index 89a2ac209f..aa6633ec9e 100644
--- a/arch/mips/include/asm/system.h
+++ b/arch/mips/include/asm/system.h
@@ -275,11 +275,13 @@ static inline void instruction_hazard_barrier(void)
 {
 	unsigned long tmp;
 
+#if defined(CONFIG_SUPPORTS_CPU_MIPS32_R2) || defined(CONFIG_SUPPORTS_CPU_MIPS64_R2)
 	asm volatile(
 	__stringify(PTR_LA) "\t%0, 1f\n"
 	"	jr.hb	%0\n"
 	"1:	.insn"
 	: "=&r"(tmp));
+#endif
 }
 
 #ifdef CONFIG_SYS_NONCACHED_MEMORY
-- 
2.40.1