[PATCH 1/2] ARM: hyp-stub: improve ABI
flat view
STALE3572d
REVIEWED: 1 (1M)
From: mark.rutland@arm.com (Mark Rutland)
Date: 2016-12-14 11:49:54
Also in:
kvmarm
1 review trailer.
On Wed, Dec 14, 2016 at 10:46:30AM +0000, Russell King wrote:
Improve the hyp-stub ABI to allow it to do more than just get/set the vectors. We follow the example in ARM64, where r0 is used as an opcode with the other registers as an argument. Signed-off-by: Russell King <redacted>
This looks good to me, though I'd suggest s/ABI/calling convention/, as this isn't strictly speaking an ABI. So FWIW: Acked-by: Mark Rutland <mark.rutland@arm.com> Thanks, Mark.
quoted hunk ↗ jump to hunk
--- arch/arm/kernel/hyp-stub.S | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-)diff --git a/arch/arm/kernel/hyp-stub.S b/arch/arm/kernel/hyp-stub.S index 15d073ae5da2..f3e9ba5fb642 100644 --- a/arch/arm/kernel/hyp-stub.S +++ b/arch/arm/kernel/hyp-stub.S@@ -22,6 +22,9 @@ #include <asm/assembler.h> #include <asm/virt.h> +#define HVC_GET_VECTORS 0 +#define HVC_SET_VECTORS 1 + #ifndef ZIMAGE /* * For the kernel proper, we need to find out the CPU boot mode long after@@ -202,9 +205,19 @@ ARM_BE8(orr r7, r7, #(1 << 25)) @ HSCTLR.EE ENDPROC(__hyp_stub_install_secondary) __hyp_stub_do_trap: - cmp r0, #-1 - mrceq p15, 4, r0, c12, c0, 0 @ get HVBAR - mcrne p15, 4, r0, c12, c0, 0 @ set HVBAR + teq r0, #HVC_GET_VECTORS + bne 1f + mrc p15, 4, r0, c12, c0, 0 @ get HVBAR + b __hyp_stub_exit + +1: teq r0, #HVC_SET_VECTORS + bne 1f + mcr p15, 4, r1, c12, c0, 0 @ set HVBAR + b __hyp_stub_exit + +1: mov r0, #-1 + +__hyp_stub_exit: __ERET ENDPROC(__hyp_stub_do_trap)@@ -231,10 +244,14 @@ ENDPROC(__hyp_stub_do_trap) * initialisation entry point. */ ENTRY(__hyp_get_vectors) - mov r0, #-1 + mov r0, #HVC_GET_VECTORS + __HVC(0) + ret lr ENDPROC(__hyp_get_vectors) - @ fall through + ENTRY(__hyp_set_vectors) + mov r1, r0 + mov r0, #HVC_SET_VECTORS __HVC(0) ret lr ENDPROC(__hyp_set_vectors)-- 2.7.4