On Mon, Dec 07, 2015 at 10:53:17AM +0000, Marc Zyngier wrote: > From: Mark Rutland <mark.rutl...@arm.com> > > Rather than crafting custom macros for reading/writing each system > register provide generics accessors, read_sysreg and write_sysreg, for > this purpose. > > Unlike read_cpuid, calls to read_exception_reg are never expected > to be optimized away or replaced with synthetic values.
What's read_exception_reg? Is it a macro somewhere? > diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h > index d48ab5b..c9c283a 100644 > --- a/arch/arm64/include/asm/sysreg.h > +++ b/arch/arm64/include/asm/sysreg.h > @@ -20,6 +20,8 @@ > #ifndef __ASM_SYSREG_H > #define __ASM_SYSREG_H > > +#include <linux/stringify.h> > + > #include <asm/opcodes.h> > > /* > @@ -208,6 +210,8 @@ > > #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" > @@ -232,6 +236,19 @@ static inline void config_sctlr_el1(u32 clear, u32 set) > val |= set; > asm volatile("msr sctlr_el1, %0" : : "r" (val)); > } > + > +#define read_sysreg(r) ({ \ > + u64 __val; \ > + asm volatile("mrs %0, " __stringify(r) : "=r" (__val)); \ > + __val; \ > +}) And maybe a comment here on why this is always volatile. Otherwise: Acked-by: Catalin Marinas <catalin.mari...@arm.com> -- Catalin -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html