2 * Copyright (c) 2014 Andrew Turner
3 * Copyright (c) 2014 The FreeBSD Foundation
6 * This software was developed by Andrew Turner under sponsorship from
7 * the FreeBSD Foundation.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 #include "opt_kstack_pages.h"
34 #include "opt_sched.h"
36 #include <machine/asm.h>
38 __FBSDID("$FreeBSD$");
40 .macro clear_step_flag pcbflags, tmp
41 tbz \pcbflags, #PCB_SINGLE_STEP_SHIFT, 999f
49 .macro set_step_flag pcbflags, tmp
50 tbz \pcbflags, #PCB_SINGLE_STEP_SHIFT, 999f
59 * void cpu_throw(struct thread *old, struct thread *new)
62 /* Of old == NULL skip disabling stepping */
65 /* If we were single stepping, disable it */
67 ldr w5, [x4, #PCB_FLAGS]
68 clear_step_flag w5, x6
72 /* Backup the new thread pointer around a call to C code */
83 /* If we are single stepping, enable it */
84 ldr w5, [x4, #PCB_FLAGS]
87 /* Restore the registers */
88 ldp x5, x6, [x4, #PCB_SP]
91 ldr x6, [x4, #PCB_TPIDRRO]
93 ldp x8, x9, [x4, #PCB_REGS + 8 * 8]
94 ldp x10, x11, [x4, #PCB_REGS + 10 * 8]
95 ldp x12, x13, [x4, #PCB_REGS + 12 * 8]
96 ldp x14, x15, [x4, #PCB_REGS + 14 * 8]
97 ldp x16, x17, [x4, #PCB_REGS + 16 * 8]
98 ldr x19, [x4, #PCB_REGS + 19 * 8]
99 ldp x20, x21, [x4, #PCB_REGS + 20 * 8]
100 ldp x22, x23, [x4, #PCB_REGS + 22 * 8]
101 ldp x24, x25, [x4, #PCB_REGS + 24 * 8]
102 ldp x26, x27, [x4, #PCB_REGS + 26 * 8]
103 ldp x28, x29, [x4, #PCB_REGS + 28 * 8]
104 ldr lr, [x4, #PCB_LR]
110 * void cpu_switch(struct thread *old, struct thread *new, struct mtx *mtx)
115 * x3 to x7, x16 and x17 are caller saved
119 * Save the old context.
121 ldr x4, [x0, #TD_PCB]
123 /* Store the callee-saved registers */
124 stp x8, x9, [x4, #PCB_REGS + 8 * 8]
125 stp x10, x11, [x4, #PCB_REGS + 10 * 8]
126 stp x12, x13, [x4, #PCB_REGS + 12 * 8]
127 stp x14, x15, [x4, #PCB_REGS + 14 * 8]
128 stp x16, x17, [x4, #PCB_REGS + 16 * 8]
129 stp x18, x19, [x4, #PCB_REGS + 18 * 8]
130 stp x20, x21, [x4, #PCB_REGS + 20 * 8]
131 stp x22, x23, [x4, #PCB_REGS + 22 * 8]
132 stp x24, x25, [x4, #PCB_REGS + 24 * 8]
133 stp x26, x27, [x4, #PCB_REGS + 26 * 8]
134 stp x28, x29, [x4, #PCB_REGS + 28 * 8]
135 str lr, [x4, #PCB_LR]
136 /* And the old stack pointer */
139 str x6, [x4, #PCB_TPIDRRO]
141 stp x5, x6, [x4, #PCB_SP]
143 /* If we were single stepping, disable it */
144 ldr w5, [x4, #PCB_FLAGS]
145 clear_step_flag w5, x6
152 /* Load the pcb address */
160 /* Move the new pcb out of the way */
168 * Release the old thread.
170 stlr x2, [x0, #TD_LOCK]
171 #if defined(SCHED_ULE) && defined(SMP)
172 /* Spin if TD_LOCK points to a blocked_lock */
173 ldr x2, =_C_LABEL(blocked_lock)
175 ldar x3, [x1, #TD_LOCK]
180 /* If we are single stepping, enable it */
181 ldr w5, [x4, #PCB_FLAGS]
184 /* Restore the registers */
185 ldp x5, x6, [x4, #PCB_SP]
188 ldr x6, [x4, #PCB_TPIDRRO]
190 ldp x8, x9, [x4, #PCB_REGS + 8 * 8]
191 ldp x10, x11, [x4, #PCB_REGS + 10 * 8]
192 ldp x12, x13, [x4, #PCB_REGS + 12 * 8]
193 ldp x14, x15, [x4, #PCB_REGS + 14 * 8]
194 ldp x16, x17, [x4, #PCB_REGS + 16 * 8]
195 ldr x19, [x4, #PCB_REGS + 19 * 8]
196 ldp x20, x21, [x4, #PCB_REGS + 20 * 8]
197 ldp x22, x23, [x4, #PCB_REGS + 22 * 8]
198 ldp x24, x25, [x4, #PCB_REGS + 24 * 8]
199 ldp x26, x27, [x4, #PCB_REGS + 26 * 8]
200 ldp x28, x29, [x4, #PCB_REGS + 28 * 8]
201 ldr lr, [x4, #PCB_LR]
203 str xzr, [x4, #PCB_REGS + 18 * 8]
205 .Lcpu_switch_panic_str:
206 .asciz "cpu_switch: %p\0"
209 ENTRY(fork_trampoline)
213 mov fp, #0 /* Stack traceback stops here. */
214 bl _C_LABEL(fork_exit)
216 /* Restore the registers other than x0 and x1 */
217 ldp x2, x3, [sp, #TF_X + 2 * 8]
218 ldp x4, x5, [sp, #TF_X + 4 * 8]
219 ldp x6, x7, [sp, #TF_X + 6 * 8]
220 ldp x8, x9, [sp, #TF_X + 8 * 8]
221 ldp x10, x11, [sp, #TF_X + 10 * 8]
222 ldp x12, x13, [sp, #TF_X + 12 * 8]
223 ldp x14, x15, [sp, #TF_X + 14 * 8]
224 ldp x16, x17, [sp, #TF_X + 16 * 8]
225 ldr x19, [sp, #TF_X + 19 * 8]
226 ldp x20, x21, [sp, #TF_X + 20 * 8]
227 ldp x22, x23, [sp, #TF_X + 22 * 8]
228 ldp x24, x25, [sp, #TF_X + 24 * 8]
229 ldp x26, x27, [sp, #TF_X + 26 * 8]
230 ldp x28, x29, [sp, #TF_X + 28 * 8]
233 * Disable interrupts to avoid
234 * overwriting spsr_el1 and sp_el0 by an IRQ exception.
238 /* Restore sp and lr */
239 ldp x0, x1, [sp, #TF_SP]
243 /* Restore elr and spsr */
244 ldp x0, x1, [sp, #TF_ELR]
248 /* Finally x0 and x1 */
249 ldp x0, x1, [sp, #TF_X + 0 * 8]
250 ldr x18, [sp, #TF_X + 18 * 8]
253 * No need for interrupts reenabling since PSR
254 * will be set to the desired value anyway.
261 /* Store the callee-saved registers */
262 stp x8, x9, [x0, #PCB_REGS + 8 * 8]
263 stp x10, x11, [x0, #PCB_REGS + 10 * 8]
264 stp x12, x13, [x0, #PCB_REGS + 12 * 8]
265 stp x14, x15, [x0, #PCB_REGS + 14 * 8]
266 stp x16, x17, [x0, #PCB_REGS + 16 * 8]
267 stp x18, x19, [x0, #PCB_REGS + 18 * 8]
268 stp x20, x21, [x0, #PCB_REGS + 20 * 8]
269 stp x22, x23, [x0, #PCB_REGS + 22 * 8]
270 stp x24, x25, [x0, #PCB_REGS + 24 * 8]
271 stp x26, x27, [x0, #PCB_REGS + 26 * 8]
272 stp x28, x29, [x0, #PCB_REGS + 28 * 8]
273 str lr, [x0, #PCB_LR]
274 /* And the old stack pointer */
277 str x6, [x0, #PCB_TPIDRRO]
279 stp x5, x6, [x0, #PCB_SP]
281 /* Store the VFP registers */
284 mov x1, x0 /* move pcb to the correct register */
285 mov x0, xzr /* td = NULL */