[PATCH v1 06/18] arm64/hyp-stub: Enable access to ALLINT

[Mark Brown]

In order to use NMIs we need to ensure that traps are disabled for it so
update HCRX_EL2 to ensure that TALLINT is not set when we detect support
for NMIs.

Signed-off-by: Mark Brown <broonie at kernel.org>
---
 arch/arm64/kernel/hyp-stub.S | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S
index 2ee18c860f2a..4e0b06467973 100644
--- a/arch/arm64/kernel/hyp-stub.S
+++ b/arch/arm64/kernel/hyp-stub.S
@@ -151,6 +151,18 @@ SYM_CODE_START_LOCAL(__finalise_el2)
 
 .Lskip_sme:
 
+	// NMIs
+	__check_override id_aa64pfr1 ID_AA64PFR1_EL1_NMI_SHIFT 4 .Linit_nmi .Lskip_nmi
+.Linit_nmi:
+	mrs	x1, id_aa64mmfr1_el1		// HCRX_EL2 present?
+	ubfx	x1, x1, #ID_AA64MMFR1_EL1_HCX_SHIFT, #4
+	cbz	x1, .Lskip_nmi
+
+	mrs_s	x1, SYS_HCRX_EL2
+	and	x1, x1, #~HCRX_EL2_TALLINT_MASK	// Don't trap ALLINT
+	msr_s	SYS_HCRX_EL2, x1
+.Lskip_nmi:
+
 	// nVHE? No way! Give me the real thing!
 	// Sanity check: MMU *must* be off
 	mrs	x1, sctlr_el2
-- 
2.30.2