arm64: kvm: allows kvm cpu hotplug

[firefly-linux-kernel-4.4.55.git] / arch / arm64 / kvm / hyp-init.S

diff --git a/arch/arm64/kvm/hyp-init.S b/arch/arm64/kvm/hyp-init.S
index 034d152c3fbe7a6afce7f7ee827b1d6825b84cde..d87635e678b7edf2ea18a6a038d2db1dba802d8c 100644 (file)
--- a/arch/arm64/kvm/hyp-init.S
+++ b/arch/arm64/kvm/hyp-init.S
@@ -152,6 +152,44 @@ merged:
        eret
 ENDPROC(__kvm_hyp_init)
 
+       /*
+        * x0: HYP boot pgd
+        * x1: HYP phys_idmap_start
+        */
+ENTRY(__kvm_hyp_reset)
+       /* We're in trampoline code in VA, switch back to boot page tables */
+       msr     ttbr0_el2, x0
+       isb
+
+       /* Ensure the PA branch doesn't find a stale tlb entry or stale code. */
+       ic      iallu
+       tlbi    alle2
+       dsb     sy
+       isb
+
+       /* Branch into PA space */
+       adr     x0, 1f
+       bfi     x1, x0, #0, #PAGE_SHIFT
+       br      x1
+
+       /* We're now in idmap, disable MMU */
+1:     mrs     x0, sctlr_el2
+       ldr     x1, =SCTLR_ELx_FLAGS
+       bic     x0, x0, x1              // Clear SCTL_M and etc
+       msr     sctlr_el2, x0
+       isb
+
+       /* Invalidate the old TLBs */
+       tlbi    alle2
+       dsb     sy
+
+       /* Install stub vectors */
+       adr_l   x0, __hyp_stub_vectors
+       msr     vbar_el2, x0
+
+       eret
+ENDPROC(__kvm_hyp_reset)
+
        .ltorg
 
        .popsection