xref: /freebsd/sys/arm64/arm64/exception.S (revision 780fb4a2)
1/*-
2 * Copyright (c) 2014 Andrew Turner
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 */
27
28#include <machine/asm.h>
29#include <machine/armreg.h>
30__FBSDID("$FreeBSD$");
31
32#include "assym.inc"
33
34	.text
35
36.macro	save_registers el
37.if \el == 1
38	mov	x18, sp
39	sub	sp, sp, #128
40.endif
41	sub	sp, sp, #(TF_SIZE + 16)
42	stp	x29, x30, [sp, #(TF_SIZE)]
43	stp	x28, x29, [sp, #(TF_X + 28 * 8)]
44	stp	x26, x27, [sp, #(TF_X + 26 * 8)]
45	stp	x24, x25, [sp, #(TF_X + 24 * 8)]
46	stp	x22, x23, [sp, #(TF_X + 22 * 8)]
47	stp	x20, x21, [sp, #(TF_X + 20 * 8)]
48	stp	x18, x19, [sp, #(TF_X + 18 * 8)]
49	stp	x16, x17, [sp, #(TF_X + 16 * 8)]
50	stp	x14, x15, [sp, #(TF_X + 14 * 8)]
51	stp	x12, x13, [sp, #(TF_X + 12 * 8)]
52	stp	x10, x11, [sp, #(TF_X + 10 * 8)]
53	stp	x8,  x9,  [sp, #(TF_X + 8  * 8)]
54	stp	x6,  x7,  [sp, #(TF_X + 6  * 8)]
55	stp	x4,  x5,  [sp, #(TF_X + 4  * 8)]
56	stp	x2,  x3,  [sp, #(TF_X + 2  * 8)]
57	stp	x0,  x1,  [sp, #(TF_X + 0  * 8)]
58	mrs	x10, elr_el1
59	mrs	x11, spsr_el1
60	mrs	x12, esr_el1
61.if \el == 0
62	mrs	x18, sp_el0
63.endif
64	str	x10, [sp, #(TF_ELR)]
65	stp	w11, w12, [sp, #(TF_SPSR)]
66	stp	x18,  lr, [sp, #(TF_SP)]
67	mrs	x18, tpidr_el1
68	add	x29, sp, #(TF_SIZE)
69.endm
70
71.macro	restore_registers el
72.if \el == 1
73	msr	daifset, #2
74	/*
75	 * Disable interrupts, x18 may change in the interrupt exception
76	 * handler.  For EL0 exceptions, do_ast already did this.
77	 */
78.endif
79	ldp	x18,  lr, [sp, #(TF_SP)]
80	ldp	x10, x11, [sp, #(TF_ELR)]
81.if \el == 0
82	msr	sp_el0, x18
83.endif
84	msr	spsr_el1, x11
85	msr	elr_el1, x10
86	ldp	x0,  x1,  [sp, #(TF_X + 0  * 8)]
87	ldp	x2,  x3,  [sp, #(TF_X + 2  * 8)]
88	ldp	x4,  x5,  [sp, #(TF_X + 4  * 8)]
89	ldp	x6,  x7,  [sp, #(TF_X + 6  * 8)]
90	ldp	x8,  x9,  [sp, #(TF_X + 8  * 8)]
91	ldp	x10, x11, [sp, #(TF_X + 10 * 8)]
92	ldp	x12, x13, [sp, #(TF_X + 12 * 8)]
93	ldp	x14, x15, [sp, #(TF_X + 14 * 8)]
94	ldp	x16, x17, [sp, #(TF_X + 16 * 8)]
95.if \el == 0
96	/*
97	 * We only restore the callee saved registers when returning to
98	 * userland as they may have been updated by a system call or signal.
99	 */
100	ldp	x18, x19, [sp, #(TF_X + 18 * 8)]
101	ldp	x20, x21, [sp, #(TF_X + 20 * 8)]
102	ldp	x22, x23, [sp, #(TF_X + 22 * 8)]
103	ldp	x24, x25, [sp, #(TF_X + 24 * 8)]
104	ldp	x26, x27, [sp, #(TF_X + 26 * 8)]
105	ldp	x28, x29, [sp, #(TF_X + 28 * 8)]
106.else
107	ldr	     x29, [sp, #(TF_X + 29 * 8)]
108.endif
109.if \el == 0
110	add	sp, sp, #(TF_SIZE + 16)
111.else
112	mov	sp, x18
113	mrs	x18, tpidr_el1
114.endif
115.endm
116
117.macro	do_ast
118	mrs	x19, daif
119	/* Make sure the IRQs are enabled before calling ast() */
120	bic	x19, x19, #PSR_I
1211:
122	/* Disable interrupts */
123	msr	daifset, #2
124
125	/* Read the current thread flags */
126	ldr	x1, [x18, #PC_CURTHREAD]	/* Load curthread */
127	ldr	x2, [x1, #TD_FLAGS]
128
129	/* Check if we have either bits set */
130	mov	x3, #((TDF_ASTPENDING|TDF_NEEDRESCHED) >> 8)
131	lsl	x3, x3, #8
132	and	x2, x2, x3
133	cbz	x2, 2f
134
135	/* Restore interrupts */
136	msr	daif, x19
137
138	/* handle the ast */
139	mov	x0, sp
140	bl	_C_LABEL(ast)
141
142	/* Re-check for new ast scheduled */
143	b	1b
1442:
145.endm
146
147ENTRY(handle_el1h_sync)
148	save_registers 1
149	ldr	x0, [x18, #PC_CURTHREAD]
150	mov	x1, sp
151	bl	do_el1h_sync
152	restore_registers 1
153	eret
154END(handle_el1h_sync)
155
156ENTRY(handle_el1h_irq)
157	save_registers 1
158	mov	x0, sp
159	bl	intr_irq_handler
160	restore_registers 1
161	eret
162END(handle_el1h_irq)
163
164ENTRY(handle_el0_sync)
165	save_registers 0
166	ldr	x0, [x18, #PC_CURTHREAD]
167	mov	x1, sp
168	str	x1, [x0, #TD_FRAME]
169	bl	do_el0_sync
170	do_ast
171	restore_registers 0
172	eret
173END(handle_el0_sync)
174
175ENTRY(handle_el0_irq)
176	save_registers 0
177	mov	x0, sp
178	bl	intr_irq_handler
179	do_ast
180	restore_registers 0
181	eret
182END(handle_el0_irq)
183
184ENTRY(handle_serror)
185	save_registers 0
186	mov	x0, sp
1871:	bl	do_serror
188	b	1b
189END(handle_serror)
190
191ENTRY(handle_empty_exception)
192	save_registers 0
193	mov	x0, sp
1941:	bl	unhandled_exception
195	b	1b
196END(handle_unhandled_exception)
197
198.macro	vempty
199	.align 7
200	b	handle_empty_exception
201.endm
202
203.macro	vector	name
204	.align 7
205	b	handle_\name
206.endm
207
208	.align 11
209	.globl exception_vectors
210exception_vectors:
211	vempty			/* Synchronous EL1t */
212	vempty			/* IRQ EL1t */
213	vempty			/* FIQ EL1t */
214	vempty			/* Error EL1t */
215
216	vector el1h_sync	/* Synchronous EL1h */
217	vector el1h_irq		/* IRQ EL1h */
218	vempty			/* FIQ EL1h */
219	vector serror		/* Error EL1h */
220
221	vector el0_sync		/* Synchronous 64-bit EL0 */
222	vector el0_irq		/* IRQ 64-bit EL0 */
223	vempty			/* FIQ 64-bit EL0 */
224	vector serror		/* Error 64-bit EL0 */
225
226	vector el0_sync		/* Synchronous 32-bit EL0 */
227	vector el0_irq		/* IRQ 32-bit EL0 */
228	vempty			/* FIQ 32-bit EL0 */
229	vector serror		/* Error 32-bit EL0 */
230
231