On Thu, Aug 31, 2017 at 06:00:42PM +0100, Dave P Martin wrote: > diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S > index 877d42f..dd22ef2 100644 > --- a/arch/arm64/mm/proc.S > +++ b/arch/arm64/mm/proc.S > @@ -27,6 +27,7 @@ > #include <asm/pgtable-hwdef.h> > #include <asm/cpufeature.h> > #include <asm/alternative.h> > +#include <asm/sysreg.h> > > #ifdef CONFIG_ARM64_64K_PAGES > #define TCR_TG_FLAGS TCR_TG0_64K | TCR_TG1_64K > @@ -186,8 +187,17 @@ ENTRY(__cpu_setup) > tlbi vmalle1 // Invalidate local TLB > dsb nsh > > - mov x0, #3 << 20 > - msr cpacr_el1, x0 // Enable FP/ASIMD > + mov x0, #3 << 20 // FEN > + > + /* SVE */ > + mrs x5, id_aa64pfr0_el1 > + ubfx x5, x5, #ID_AA64PFR0_SVE_SHIFT, #4 > + cbz x5, 1f > + > + bic x0, x0, #CPACR_EL1_ZEN > + orr x0, x0, #CPACR_EL1_ZEN_EL1EN // SVE: trap for EL0, not EL1 > +1: msr cpacr_el1, x0 // Enable FP/ASIMD
For EL1, I wonder whether we could move this later to cpufeature.c. IIRC I tried to do the same with FPSIMD but hit an issue with EFI run-time services (I may be wrong though). -- Catalin _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
