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>
37 #include <machine/armreg.h>
39 __FBSDID("$FreeBSD$");
41 .macro clear_step_flag pcbflags, tmp
42 tbz \pcbflags, #PCB_SINGLE_STEP_SHIFT, 999f
44 bic \tmp, \tmp, #MDSCR_SS
50 .macro set_step_flag pcbflags, tmp
51 tbz \pcbflags, #PCB_SINGLE_STEP_SHIFT, 999f
53 orr \tmp, \tmp, #MDSCR_SS
60 * void cpu_throw(struct thread *old, struct thread *new)
63 /* Of old == NULL skip disabling stepping */
66 /* If we were single stepping, disable it */
68 ldr w5, [x4, #PCB_FLAGS]
69 clear_step_flag w5, x6
73 /* Backup the new thread pointer around a call to C code */
84 /* If we are single stepping, enable it */
85 ldr w5, [x4, #PCB_FLAGS]
88 /* Restore the registers */
89 ldp x5, x6, [x4, #PCB_SP]
92 ldr x6, [x4, #PCB_TPIDRRO]
94 ldp x8, x9, [x4, #PCB_REGS + 8 * 8]
95 ldp x10, x11, [x4, #PCB_REGS + 10 * 8]
96 ldp x12, x13, [x4, #PCB_REGS + 12 * 8]
97 ldp x14, x15, [x4, #PCB_REGS + 14 * 8]
98 ldp x16, x17, [x4, #PCB_REGS + 16 * 8]
99 ldr x19, [x4, #PCB_REGS + 19 * 8]
100 ldp x20, x21, [x4, #PCB_REGS + 20 * 8]
101 ldp x22, x23, [x4, #PCB_REGS + 22 * 8]
102 ldp x24, x25, [x4, #PCB_REGS + 24 * 8]
103 ldp x26, x27, [x4, #PCB_REGS + 26 * 8]
104 ldp x28, x29, [x4, #PCB_REGS + 28 * 8]
105 ldr lr, [x4, #PCB_LR]
111 * void cpu_switch(struct thread *old, struct thread *new, struct mtx *mtx)
116 * x3 to x7, x16 and x17 are caller saved
120 * Save the old context.
122 ldr x4, [x0, #TD_PCB]
124 /* Store the callee-saved registers */
125 stp x8, x9, [x4, #PCB_REGS + 8 * 8]
126 stp x10, x11, [x4, #PCB_REGS + 10 * 8]
127 stp x12, x13, [x4, #PCB_REGS + 12 * 8]
128 stp x14, x15, [x4, #PCB_REGS + 14 * 8]
129 stp x16, x17, [x4, #PCB_REGS + 16 * 8]
130 stp x18, x19, [x4, #PCB_REGS + 18 * 8]
131 stp x20, x21, [x4, #PCB_REGS + 20 * 8]
132 stp x22, x23, [x4, #PCB_REGS + 22 * 8]
133 stp x24, x25, [x4, #PCB_REGS + 24 * 8]
134 stp x26, x27, [x4, #PCB_REGS + 26 * 8]
135 stp x28, x29, [x4, #PCB_REGS + 28 * 8]
136 str lr, [x4, #PCB_LR]
137 /* And the old stack pointer */
140 str x6, [x4, #PCB_TPIDRRO]
142 stp x5, x6, [x4, #PCB_SP]
144 /* If we were single stepping, disable it */
145 ldr w5, [x4, #PCB_FLAGS]
146 clear_step_flag w5, x6
153 /* Load the pcb address */
161 /* Move the new pcb out of the way */
169 * Release the old thread.
171 stlr x2, [x0, #TD_LOCK]
172 #if defined(SCHED_ULE) && defined(SMP)
173 /* Spin if TD_LOCK points to a blocked_lock */
174 ldr x2, =_C_LABEL(blocked_lock)
176 ldar x3, [x1, #TD_LOCK]
181 /* If we are single stepping, enable it */
182 ldr w5, [x4, #PCB_FLAGS]
185 /* Restore the registers */
186 ldp x5, x6, [x4, #PCB_SP]
189 ldr x6, [x4, #PCB_TPIDRRO]
191 ldp x8, x9, [x4, #PCB_REGS + 8 * 8]
192 ldp x10, x11, [x4, #PCB_REGS + 10 * 8]
193 ldp x12, x13, [x4, #PCB_REGS + 12 * 8]
194 ldp x14, x15, [x4, #PCB_REGS + 14 * 8]
195 ldp x16, x17, [x4, #PCB_REGS + 16 * 8]
196 ldr x19, [x4, #PCB_REGS + 19 * 8]
197 ldp x20, x21, [x4, #PCB_REGS + 20 * 8]
198 ldp x22, x23, [x4, #PCB_REGS + 22 * 8]
199 ldp x24, x25, [x4, #PCB_REGS + 24 * 8]
200 ldp x26, x27, [x4, #PCB_REGS + 26 * 8]
201 ldp x28, x29, [x4, #PCB_REGS + 28 * 8]
202 ldr lr, [x4, #PCB_LR]
204 str xzr, [x4, #PCB_REGS + 18 * 8]
208 ENTRY(fork_trampoline)
212 mov fp, #0 /* Stack traceback stops here. */
213 bl _C_LABEL(fork_exit)
216 * Disable interrupts to avoid
217 * overwriting spsr_el1 and sp_el0 by an IRQ exception.
219 msr daifset, #(DAIF_D | DAIF_INTR)
221 /* Restore sp, lr, elr, and spsr */
222 ldp x18, lr, [sp, #TF_SP]
223 ldp x10, x11, [sp, #TF_ELR]
228 /* Restore the CPU registers */
229 ldp x0, x1, [sp, #TF_X + 0 * 8]
230 ldp x2, x3, [sp, #TF_X + 2 * 8]
231 ldp x4, x5, [sp, #TF_X + 4 * 8]
232 ldp x6, x7, [sp, #TF_X + 6 * 8]
233 ldp x8, x9, [sp, #TF_X + 8 * 8]
234 ldp x10, x11, [sp, #TF_X + 10 * 8]
235 ldp x12, x13, [sp, #TF_X + 12 * 8]
236 ldp x14, x15, [sp, #TF_X + 14 * 8]
237 ldp x16, x17, [sp, #TF_X + 16 * 8]
238 ldp x18, x19, [sp, #TF_X + 18 * 8]
239 ldp x20, x21, [sp, #TF_X + 20 * 8]
240 ldp x22, x23, [sp, #TF_X + 22 * 8]
241 ldp x24, x25, [sp, #TF_X + 24 * 8]
242 ldp x26, x27, [sp, #TF_X + 26 * 8]
243 ldp x28, x29, [sp, #TF_X + 28 * 8]
246 * No need for interrupts reenabling since PSR
247 * will be set to the desired value anyway.
254 /* Store the callee-saved registers */
255 stp x8, x9, [x0, #PCB_REGS + 8 * 8]
256 stp x10, x11, [x0, #PCB_REGS + 10 * 8]
257 stp x12, x13, [x0, #PCB_REGS + 12 * 8]
258 stp x14, x15, [x0, #PCB_REGS + 14 * 8]
259 stp x16, x17, [x0, #PCB_REGS + 16 * 8]
260 stp x18, x19, [x0, #PCB_REGS + 18 * 8]
261 stp x20, x21, [x0, #PCB_REGS + 20 * 8]
262 stp x22, x23, [x0, #PCB_REGS + 22 * 8]
263 stp x24, x25, [x0, #PCB_REGS + 24 * 8]
264 stp x26, x27, [x0, #PCB_REGS + 26 * 8]
265 stp x28, x29, [x0, #PCB_REGS + 28 * 8]
266 str lr, [x0, #PCB_LR]
267 /* And the old stack pointer */
270 str x6, [x0, #PCB_TPIDRRO]
272 stp x5, x6, [x0, #PCB_SP]
274 /* Store the VFP registers */
277 mov x1, x0 /* move pcb to the correct register */
278 mov x0, xzr /* td = NULL */