[PATCH] riscv: fix scratch register clearing in M-mode.

[Greentime Hu]

This patch fixes that the sscratch register clearing in M-mode. It cleared
sscratch register in M-mode, but it should clear mscratch register. That will
cause kernel trap if the CPU core doesn't support S-mode when trying to access
sscratch.

Fixes: 9e80635619b5 ("riscv: clear the instruction cache and all registers when booting")
Signed-off-by: Greentime Hu <greentime.hu@xxxxxxxxxx>
---
 arch/riscv/kernel/head.S | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 84a6f0a4b120..797802c73dee 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -246,7 +246,7 @@ ENTRY(reset_regs)
 	li	t4, 0
 	li	t5, 0
 	li	t6, 0
-	csrw	sscratch, 0
+	csrw	CSR_SCRATCH, 0
 
 #ifdef CONFIG_FPU
 	csrr	t0, CSR_MISA
-- 
2.17.1