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 73 742: cmp x0, #HVC_SOFT_RESTART 75 b.ne 3f 76 mov x0, x2 77 mov x2, x4 78 mov x4, x1 79 mov x1, x3 80 br x4 // no return 81 82 /* Someone called kvm_call_hyp() against the hyp-stub... */ 833: mov x0, #ARM_EXCEPTION_HYP_GONE 84 859: eret 86ENDPROC(el1_sync) 87 88.macro invalid_vector label 89\label: 90 b \label 91ENDPROC(\label) 92.endm 93 94 invalid_vector el2_sync_invalid 95 invalid_vector el2_irq_invalid 96 invalid_vector el2_fiq_invalid 97 invalid_vector el2_error_invalid 98 invalid_vector el1_sync_invalid 99 invalid_vector el1_irq_invalid 100 invalid_vector el1_fiq_invalid 101 invalid_vector el1_error_invalid 102 103/* 104 * __hyp_set_vectors: Call this after boot to set the initial hypervisor 105 * vectors as part of hypervisor installation. On an SMP system, this should 106 * be called on each CPU. 107 * 108 * x0 must be the physical address of the new vector table, and must be 109 * 2KB aligned. 110 * 111 * Before calling this, you must check that the stub hypervisor is installed 112 * everywhere, by waiting for any secondary CPUs to be brought up and then 113 * checking that is_hyp_mode_available() is true. 114 * 115 * If not, there is a pre-existing hypervisor, some CPUs failed to boot, or 116 * something else went wrong... in such cases, trying to install a new 117 * hypervisor is unlikely to work as desired. 118 * 119 * When you call into your shiny new hypervisor, sp_el2 will contain junk, 120 * so you will need to set that to something sensible at the new hypervisor's 121 * initialisation entry point. 122 */ 123 124ENTRY(__hyp_get_vectors) 125 str lr, [sp, #-16]! 126 mov x0, #HVC_GET_VECTORS 127 hvc #0 128 ldr lr, [sp], #16 129 ret 130ENDPROC(__hyp_get_vectors) 131 132ENTRY(__hyp_set_vectors) 133 str lr, [sp, #-16]! 134 mov x1, x0 135 mov x0, #HVC_SET_VECTORS 136 hvc #0 137 ldr lr, [sp], #16 138 ret 139ENDPROC(__hyp_set_vectors) 140