From 22a4e006be52fbd5249f46c36c4d8016c15b9fa7 Mon Sep 17 00:00:00 2001 From: Heinrich Schuchardt Date: Wed, 27 May 2020 20:04:24 +0200 Subject: [PATCH] arm: use correct argument size of special registers Compiling with clang on ARMv8 shows errors like: ./arch/arm/include/asm/system.h:162:32: note: use constraint modifier "w" asm volatile("msr sctlr_el1, %0" : : "r" (val) : "cc"); ^~ %w0 These errors are due to using an incorrect size for the variables used for writing to and reading from special registers which have 64 bits on ARMv8. Mask off reserved bits when reading the exception level. Signed-off-by: Heinrich Schuchardt --- arch/arm/include/asm/system.h | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h index 7a40b56..b8c1b4e 100644 --- a/arch/arm/include/asm/system.h +++ b/arch/arm/include/asm/system.h @@ -133,14 +133,16 @@ enum dcache_option { static inline unsigned int current_el(void) { - unsigned int el; + unsigned long el; + asm volatile("mrs %0, CurrentEL" : "=r" (el) : : "cc"); - return el >> 2; + return 3 & (el >> 2); } static inline unsigned int get_sctlr(void) { - unsigned int el, val; + unsigned int el; + unsigned long val; el = current_el(); if (el == 1) @@ -153,7 +155,7 @@ static inline unsigned int get_sctlr(void) return val; } -static inline void set_sctlr(unsigned int val) +static inline void set_sctlr(unsigned long val) { unsigned int el; -- 2.7.4