1/* 2 * Hypervisor stub 3 * 4 * Copyright (C) 2012 ARM Ltd. 5 * Author: Marc Zyngier <marc.zyngier@arm.com> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19 20#include <linux/init.h> 21#include <linux/linkage.h> 22#include <linux/irqchip/arm-gic-v3.h> 23 24#include <asm/assembler.h> 25#include <asm/kvm_arm.h> 26#include <asm/kvm_asm.h> 27#include <asm/ptrace.h> 28#include <asm/virt.h> 29 30 .text 31 .align 11 32 33ENTRY(__hyp_stub_vectors) 34 ventry el2_sync_invalid // Synchronous EL2t 35 ventry el2_irq_invalid // IRQ EL2t 36 ventry el2_fiq_invalid // FIQ EL2t 37 ventry el2_error_invalid // Error EL2t 38 39 ventry el2_sync_invalid // Synchronous EL2h 40 ventry el2_irq_invalid // IRQ EL2h 41 ventry el2_fiq_invalid // FIQ EL2h 42 ventry el2_error_invalid // Error EL2h 43 44 ventry el1_sync // Synchronous 64-bit EL1 45 ventry el1_irq_invalid // IRQ 64-bit EL1 46 ventry el1_fiq_invalid // FIQ 64-bit EL1 47 ventry el1_error_invalid // Error 64-bit EL1 48 49 ventry el1_sync_invalid // Synchronous 32-bit EL1 50 ventry el1_irq_invalid // IRQ 32-bit EL1 51 ventry el1_fiq_invalid // FIQ 32-bit EL1 52 ventry el1_error_invalid // Error 32-bit EL1 53ENDPROC(__hyp_stub_vectors) 54 55 .align 11 56 57el1_sync: 58 mrs x30, esr_el2 59 lsr x30, x30, #ESR_ELx_EC_SHIFT 60 61 cmp x30, #ESR_ELx_EC_HVC64 62 b.ne 9f // Not an HVC trap 63 64 cmp x0, #HVC_GET_VECTORS 65 b.ne 1f 66 mrs x0, vbar_el2 67 b 9f 68 691: cmp x0, #HVC_SET_VECTORS 70 b.ne 2f 71 msr vbar_el2, x1 72 b 9f 73 74 /* Someone called kvm_call_hyp() against the hyp-stub... */ 752: mov x0, #ARM_EXCEPTION_HYP_GONE 76 779: eret 78ENDPROC(el1_sync) 79 80.macro invalid_vector label 81\label: 82 b \label 83ENDPROC(\label) 84.endm 85 86 invalid_vector el2_sync_invalid 87 invalid_vector el2_irq_invalid 88 invalid_vector el2_fiq_invalid 89 invalid_vector el2_error_invalid 90 invalid_vector el1_sync_invalid 91 invalid_vector el1_irq_invalid 92 invalid_vector el1_fiq_invalid 93 invalid_vector el1_error_invalid 94 95/* 96 * __hyp_set_vectors: Call this after boot to set the initial hypervisor 97 * vectors as part of hypervisor installation. On an SMP system, this should 98 * be called on each CPU. 99 * 100 * x0 must be the physical address of the new vector table, and must be 101 * 2KB aligned. 102 * 103 * Before calling this, you must check that the stub hypervisor is installed 104 * everywhere, by waiting for any secondary CPUs to be brought up and then 105 * checking that is_hyp_mode_available() is true. 106 * 107 * If not, there is a pre-existing hypervisor, some CPUs failed to boot, or 108 * something else went wrong... in such cases, trying to install a new 109 * hypervisor is unlikely to work as desired. 110 * 111 * When you call into your shiny new hypervisor, sp_el2 will contain junk, 112 * so you will need to set that to something sensible at the new hypervisor's 113 * initialisation entry point. 114 */ 115 116ENTRY(__hyp_get_vectors) 117 str lr, [sp, #-16]! 118 mov x0, #HVC_GET_VECTORS 119 hvc #0 120 ldr lr, [sp], #16 121 ret 122ENDPROC(__hyp_get_vectors) 123 124ENTRY(__hyp_set_vectors) 125 str lr, [sp, #-16]! 126 mov x1, x0 127 mov x0, #HVC_SET_VECTORS 128 hvc #0 129 ldr lr, [sp], #16 130 ret 131ENDPROC(__hyp_set_vectors) 132