From 4d2583dba13f9313f21fb58fb3a4c51b11770e44 Mon Sep 17 00:00:00 2001
From: Bin Meng <bmeng.cn@gmail.com>
Date: Wed, 10 Jul 2019 23:43:13 -0700
Subject: riscv: Access CSRs using CSR numbers

We should prefer accessing CSRs using their CSR numbers
because:
1. It compiles fine with older toolchains.
2. We can use latest CSR names in #define macro names of CSR
   numbers as-per RISC-V spec.
3. We can access newly added CSRs even if toolchain does not
   recognize newly added CSRs by name.

This commit is inspired from Linux kernel commit a3182c91ef4e
("RISC-V: Access CSRs using CSR numbers").

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
---
 arch/riscv/cpu/start.S | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

(limited to 'arch/riscv/cpu/start.S')

diff --git a/arch/riscv/cpu/start.S b/arch/riscv/cpu/start.S
index 60ac8c621e..e06db404f5 100644
--- a/arch/riscv/cpu/start.S
+++ b/arch/riscv/cpu/start.S
@@ -13,7 +13,6 @@
 #include <config.h>
 #include <common.h>
 #include <elf.h>
-#include <asm/csr.h>
 #include <asm/encoding.h>
 #include <generated/asm-offsets.h>
 
@@ -41,7 +40,7 @@ secondary_harts_relocation_error:
 .globl _start
 _start:
 #ifdef CONFIG_RISCV_MMODE
-	csrr	a0, mhartid
+	csrr	a0, CSR_MHARTID
 #endif
 
 	/* save hart id and dtb pointer */
-- 
cgit