[linux-2.6-block.git] / arch / arm64 / kernel / hyp-stub.S

/*
 * Hypervisor stub
 *
 * Copyright (C) 2012 ARM Ltd.
 * Author:	Marc Zyngier <marc.zyngier@arm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/init.h>
#include <linux/linkage.h>
#include <linux/irqchip/arm-gic-v3.h>

#include <asm/assembler.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_asm.h>
#include <asm/ptrace.h>
#include <asm/virt.h>

	.text
	.align 11

ENTRY(__hyp_stub_vectors)
	ventry	el2_sync_invalid		// Synchronous EL2t
	ventry	el2_irq_invalid			// IRQ EL2t
	ventry	el2_fiq_invalid			// FIQ EL2t
	ventry	el2_error_invalid		// Error EL2t

	ventry	el2_sync_invalid		// Synchronous EL2h
	ventry	el2_irq_invalid			// IRQ EL2h
	ventry	el2_fiq_invalid			// FIQ EL2h
	ventry	el2_error_invalid		// Error EL2h

	ventry	el1_sync			// Synchronous 64-bit EL1
	ventry	el1_irq_invalid			// IRQ 64-bit EL1
	ventry	el1_fiq_invalid			// FIQ 64-bit EL1
	ventry	el1_error_invalid		// Error 64-bit EL1

	ventry	el1_sync_invalid		// Synchronous 32-bit EL1
	ventry	el1_irq_invalid			// IRQ 32-bit EL1
	ventry	el1_fiq_invalid			// FIQ 32-bit EL1
	ventry	el1_error_invalid		// Error 32-bit EL1
ENDPROC(__hyp_stub_vectors)

	.align 11

el1_sync:
	mrs	x30, esr_el2
	lsr	x30, x30, #ESR_ELx_EC_SHIFT

	cmp	x30, #ESR_ELx_EC_HVC64
	b.ne	9f				// Not an HVC trap

	cmp	x0, #HVC_GET_VECTORS
	b.ne	1f
	mrs	x0, vbar_el2
	b	9f

1:	cmp	x0, #HVC_SET_VECTORS
	b.ne	2f
	msr	vbar_el2, x1
	b	9f

2:	cmp	x0, #HVC_SOFT_RESTART
	b.ne	3f
	mov	x0, x2
	mov	x2, x4
	mov	x4, x1
	mov	x1, x3
	br	x4				// no return

	/* Someone called kvm_call_hyp() against the hyp-stub... */
3:	mov	x0, #ARM_EXCEPTION_HYP_GONE

9:	eret
ENDPROC(el1_sync)

.macro invalid_vector	label
\label:
	b \label
ENDPROC(\label)
.endm

	invalid_vector	el2_sync_invalid
	invalid_vector	el2_irq_invalid
	invalid_vector	el2_fiq_invalid
	invalid_vector	el2_error_invalid
	invalid_vector	el1_sync_invalid
	invalid_vector	el1_irq_invalid
	invalid_vector	el1_fiq_invalid
	invalid_vector	el1_error_invalid

/*
 * __hyp_set_vectors: Call this after boot to set the initial hypervisor
 * vectors as part of hypervisor installation.  On an SMP system, this should
 * be called on each CPU.
 *
 * x0 must be the physical address of the new vector table, and must be
 * 2KB aligned.
 *
 * Before calling this, you must check that the stub hypervisor is installed
 * everywhere, by waiting for any secondary CPUs to be brought up and then
 * checking that is_hyp_mode_available() is true.
 *
 * If not, there is a pre-existing hypervisor, some CPUs failed to boot, or
 * something else went wrong... in such cases, trying to install a new
 * hypervisor is unlikely to work as desired.
 *
 * When you call into your shiny new hypervisor, sp_el2 will contain junk,
 * so you will need to set that to something sensible at the new hypervisor's
 * initialisation entry point.
 */

ENTRY(__hyp_get_vectors)
	str	lr, [sp, #-16]!
	mov	x0, #HVC_GET_VECTORS
	hvc	#0
	ldr	lr, [sp], #16
	ret
ENDPROC(__hyp_get_vectors)

ENTRY(__hyp_set_vectors)
	str	lr, [sp, #-16]!
	mov	x1, x0
	mov	x0, #HVC_SET_VECTORS
	hvc	#0
	ldr	lr, [sp], #16
	ret
ENDPROC(__hyp_set_vectors)
Commit	Line	Data
712c6ff4 MZ	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>
021f6537	22	#include <linux/irqchip/arm-gic-v3.h>
712c6ff4 MZ	23
712c6ff4 MZ	24	#include <asm/assembler.h>
ad72e59f	25	#include <asm/kvm_arm.h>
c94b0cf2	26	#include <asm/kvm_asm.h>
712c6ff4 MZ	27	#include <asm/ptrace.h>
	28	#include <asm/virt.h>
	29
	30	.text
	31	.align 11
	32
	33	ENTRY(__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
	53	ENDPROC(__hyp_stub_vectors)
	54
	55	.align 11
	56
	57	el1_sync:
ad72e59f GL	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
	69	1: cmp x0, #HVC_SET_VECTORS
	70	b.ne 2f
	71	msr vbar_el2, x1
	72	b 9f
	73
f9076ecf GL	74	2: 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
c94b0cf2	82	/* Someone called kvm_call_hyp() against the hyp-stub... */
f9076ecf	83	3: mov x0, #ARM_EXCEPTION_HYP_GONE
ad72e59f GL	84
ad72e59f GL	85	9: eret
712c6ff4 MZ	86	ENDPROC(el1_sync)
	87
	88	.macro invalid_vector label
	89	\label:
	90	b \label
	91	ENDPROC(\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
	124	ENTRY(__hyp_get_vectors)
00a44cda	125	str lr, [sp, #-16]!
ad72e59f	126	mov x0, #HVC_GET_VECTORS
712c6ff4	127	hvc #0
00a44cda	128	ldr lr, [sp], #16
712c6ff4 MZ	129	ret
712c6ff4 MZ	130	ENDPROC(__hyp_get_vectors)
00a44cda JM	131
	132	ENTRY(__hyp_set_vectors)
	133	str lr, [sp, #-16]!
ad72e59f GL	134	mov x1, x0
ad72e59f GL	135	mov x0, #HVC_SET_VECTORS
00a44cda JM	136	hvc #0
	137	ldr lr, [sp], #16
	138	ret
712c6ff4	139	ENDPROC(__hyp_set_vectors)