From 82deae0fc8ba256c1061dd4de42f0ef6cb9f954f Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 9 Jun 2014 19:47:09 +0100 Subject: [PATCH] arm/arm64: Add new is_kernel_in_hyp_mode predicate With ARMv8.1 VHE extension, it will be possible to run the kernel at EL2 (aka HYP mode). In order for the kernel to easily find out where it is running, add a new predicate that returns whether or not the kernel is in HYP mode. For completeness, the 32bit code also get such a predicate (always returning false) so that code common to both architecture (timers, KVM) can use it transparently. Acked-by: Christoffer Dall Acked-by: Catalin Marinas Signed-off-by: Marc Zyngier --- arch/arm/include/asm/virt.h | 5 +++++ arch/arm64/include/asm/virt.h | 10 ++++++++++ 2 files changed, 15 insertions(+) diff --git a/arch/arm/include/asm/virt.h b/arch/arm/include/asm/virt.h index 5fdbfea6defb..d4ceaf5f299b 100644 --- a/arch/arm/include/asm/virt.h +++ b/arch/arm/include/asm/virt.h @@ -75,6 +75,11 @@ static inline bool is_hyp_mode_mismatched(void) return !!(__boot_cpu_mode & BOOT_CPU_MODE_MISMATCH); } +static inline bool is_kernel_in_hyp_mode(void) +{ + return false; +} + /* The section containing the hypervisor text */ extern char __hyp_text_start[]; extern char __hyp_text_end[]; diff --git a/arch/arm64/include/asm/virt.h b/arch/arm64/include/asm/virt.h index 7a5df5252dd7..9f22dd607958 100644 --- a/arch/arm64/include/asm/virt.h +++ b/arch/arm64/include/asm/virt.h @@ -23,6 +23,8 @@ #ifndef __ASSEMBLY__ +#include + /* * __boot_cpu_mode records what mode CPUs were booted in. * A correctly-implemented bootloader must start all CPUs in the same mode: @@ -50,6 +52,14 @@ static inline bool is_hyp_mode_mismatched(void) return __boot_cpu_mode[0] != __boot_cpu_mode[1]; } +static inline bool is_kernel_in_hyp_mode(void) +{ + u64 el; + + asm("mrs %0, CurrentEL" : "=r" (el)); + return el == CurrentEL_EL2; +} + /* The section containing the hypervisor text */ extern char __hyp_text_start[]; extern char __hyp_text_end[]; -- GitLab