diff options
| author | Mark Rutland <mark.rutland@arm.com> | 2015-11-05 15:09:17 +0000 |
|---|---|---|
| committer | Alex Shi <alex.shi@linaro.org> | 2016-05-24 10:36:08 +0800 |
| commit | 69b965f5fc762f01a2cc30b6e88edec5d0caa0af (patch) | |
| tree | e2972ec7cb325d175a74c09f7f8d469384eeb39e /arch | |
| parent | 867ffcc58cbfb67f5cea958155c301bb9e83b634 (diff) | |
arm64: Add macros to read/write system registers
Rather than crafting custom macros for reading/writing each system
register provide generics accessors, read_sysreg and write_sysreg, for
this purpose.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Suzuki Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
(cherry picked from commit 3600c2fdc09a43a30909743569e35a29121602ed)
Signed-off-by: Alex Shi <alex.shi@linaro.org>
Conflicts:
arch/arm64/include/asm/sysreg.h
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/include/asm/sysreg.h | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index c94a18e3e54f..1f44a4b6280a 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -20,6 +20,10 @@ #ifndef __ASM_SYSREG_H #define __ASM_SYSREG_H +#include <linux/stringify.h> + +#include <asm/opcodes.h> + /* * ARMv8 ARM reserves the following encoding for system registers: * (Ref: ARMv8 ARM, Section: "System instruction class encoding overview", @@ -67,6 +71,8 @@ #else +#include <linux/types.h> + asm( " .irp num,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30\n" " .equ __reg_num_x\\num, \\num\n" @@ -91,6 +97,23 @@ static inline void config_sctlr_el1(u32 clear, u32 set) val |= set; asm volatile("msr sctlr_el1, %0" : : "r" (val)); } + +/* + * Unlike read_cpuid, calls to read_sysreg are never expected to be + * optimized away or replaced with synthetic values. + */ +#define read_sysreg(r) ({ \ + u64 __val; \ + asm volatile("mrs %0, " __stringify(r) : "=r" (__val)); \ + __val; \ +}) + +#define write_sysreg(v, r) do { \ + u64 __val = (u64)v; \ + asm volatile("msr " __stringify(r) ", %0" \ + : : "r" (__val)); \ +} while (0) + #endif #endif /* __ASM_SYSREG_H */ |