2 * Copyright (c) 1982, 1986 The Regents of the University of California.
3 * Copyright (c) 1989, 1990 William Jolitz
4 * Copyright (c) 1994 John Dyson
7 * This code is derived from software contributed to Berkeley by
8 * the Systems Programming Group of the University of Utah Computer
9 * Science Department, and William Jolitz.
11 * Redistribution and use in source and binary :forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the University of
22 * California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 * from: @(#)vm_machdep.c 7.3 (Berkeley) 5/13/91
40 * Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$
43 #include "opt_compat.h"
45 #include <sys/cdefs.h>
46 __FBSDID("$FreeBSD$");
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/kernel.h>
51 #include <sys/malloc.h>
54 #include <sys/socketvar.h>
55 #include <sys/syscall.h>
56 #include <sys/sysctl.h>
57 #include <sys/sysent.h>
58 #include <sys/unistd.h>
60 #include <machine/cpu.h>
61 #include <machine/frame.h>
62 #include <machine/pcb.h>
63 #include <machine/sysarch.h>
65 #include <sys/mutex.h>
69 #include <vm/vm_extern.h>
70 #include <vm/vm_kern.h>
71 #include <vm/vm_page.h>
72 #include <vm/vm_map.h>
73 #include <vm/vm_param.h>
74 #include <vm/vm_pageout.h>
76 #include <vm/uma_int.h>
78 #include <machine/md_var.h>
79 #include <machine/vfp.h>
82 * struct switchframe and trapframe must both be a multiple of 8
83 * for correct stack alignment.
85 _Static_assert((sizeof(struct switchframe) % 8) == 0, "Bad alignment");
86 _Static_assert((sizeof(struct trapframe) % 8) == 0, "Bad alignment");
88 uint32_t initial_fpscr = VFPSCR_DN | VFPSCR_FZ;
91 * Finish a fork operation, with process p2 nearly set up.
92 * Copy and update the pcb, set up the stack so that the child
93 * ready to run and return to user mode.
96 cpu_fork(struct thread *td1, struct proc *p2, struct thread *td2, int flags)
102 if ((flags & RFPROC) == 0)
105 /* Point the pcb to the top of the stack */
106 pcb2 = (struct pcb *)
107 (td2->td_kstack + td2->td_kstack_pages * PAGE_SIZE) - 1;
109 #ifndef CPU_XSCALE_CORE3
110 pmap_use_minicache(td2->td_kstack, td2->td_kstack_pages * PAGE_SIZE);
114 /* Store actual state of VFP */
115 if (curthread == td1) {
117 vfp_store(&td1->td_pcb->pcb_vfpstate, false);
123 /* Clone td1's pcb */
124 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2));
126 /* Point to mdproc and then copy over td1's contents */
128 bcopy(&td1->td_proc->p_md, mdp2, sizeof(*mdp2));
130 /* Point the frame to the stack in front of pcb and copy td1's frame */
131 td2->td_frame = (struct trapframe *)pcb2 - 1;
132 *td2->td_frame = *td1->td_frame;
135 * Create a new fresh stack for the new process.
136 * Copy the trap frame for the return to user mode as if from a
137 * syscall. This copies most of the user mode register values.
139 pmap_set_pcb_pagedir(vmspace_pmap(p2->p_vmspace), pcb2);
140 pcb2->pcb_regs.sf_r4 = (register_t)fork_return;
141 pcb2->pcb_regs.sf_r5 = (register_t)td2;
142 pcb2->pcb_regs.sf_lr = (register_t)fork_trampoline;
143 pcb2->pcb_regs.sf_sp = STACKALIGN(td2->td_frame);
145 pcb2->pcb_regs.sf_tpidrurw = (register_t)get_tls();
148 pcb2->pcb_vfpcpu = -1;
149 pcb2->pcb_vfpstate.fpscr = initial_fpscr;
152 tf->tf_spsr &= ~PSR_C;
157 /* Setup to release spin count in fork_exit(). */
158 td2->td_md.md_spinlock_count = 1;
159 td2->td_md.md_saved_cspr = PSR_SVC32_MODE;
161 td2->td_md.md_tp = *(register_t *)ARM_TP_ADDRESS;
166 cpu_thread_swapin(struct thread *td)
171 cpu_thread_swapout(struct thread *td)
176 cpu_set_syscall_retval(struct thread *td, int error)
178 struct trapframe *frame;
184 frame = td->td_frame;
189 * __syscall returns an off_t while most other syscalls return an
190 * int. As an off_t is 64-bits and an int is 32-bits we need to
191 * place the returned data into r1. As the lseek and freebsd6_lseek
192 * syscalls also return an off_t they do not need this fixup.
195 if (call == SYS___syscall) {
196 register_t *ap = &frame->tf_r0;
197 register_t code = ap[_QUAD_LOWWORD];
198 if (td->td_proc->p_sysent->sv_mask)
199 code &= td->td_proc->p_sysent->sv_mask;
200 fixup = (code != SYS_lseek);
208 frame->tf_r1 = td->td_retval[0];
210 frame->tf_r0 = td->td_retval[0];
211 frame->tf_r1 = td->td_retval[1];
213 frame->tf_spsr &= ~PSR_C; /* carry bit */
217 * Reconstruct the pc to point at the swi.
220 if ((frame->tf_spsr & PSR_T) != 0)
221 frame->tf_pc -= THUMB_INSN_SIZE;
224 frame->tf_pc -= INSN_SIZE;
230 frame->tf_r0 = SV_ABI_ERRNO(td->td_proc, error);
231 frame->tf_spsr |= PSR_C; /* carry bit */
237 * Initialize machine state, mostly pcb and trap frame for a new
238 * thread, about to return to userspace. Put enough state in the new
239 * thread's PCB to get it to go back to the fork_return(), which
240 * finalizes the thread state and handles peculiarities of the first
241 * return to userspace for the new thread.
244 cpu_copy_thread(struct thread *td, struct thread *td0)
247 bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe));
248 bcopy(td0->td_pcb, td->td_pcb, sizeof(struct pcb));
250 td->td_pcb->pcb_regs.sf_r4 = (register_t)fork_return;
251 td->td_pcb->pcb_regs.sf_r5 = (register_t)td;
252 td->td_pcb->pcb_regs.sf_lr = (register_t)fork_trampoline;
253 td->td_pcb->pcb_regs.sf_sp = STACKALIGN(td->td_frame);
255 td->td_frame->tf_spsr &= ~PSR_C;
256 td->td_frame->tf_r0 = 0;
258 /* Setup to release spin count in fork_exit(). */
259 td->td_md.md_spinlock_count = 1;
260 td->td_md.md_saved_cspr = PSR_SVC32_MODE;
264 * Set that machine state for performing an upcall that starts
265 * the entry function with the given argument.
268 cpu_set_upcall(struct thread *td, void (*entry)(void *), void *arg,
271 struct trapframe *tf = td->td_frame;
273 tf->tf_usr_sp = STACKALIGN((int)stack->ss_sp + stack->ss_size);
274 tf->tf_pc = (int)entry;
275 tf->tf_r0 = (int)arg;
276 tf->tf_spsr = PSR_USR32_MODE;
280 cpu_set_user_tls(struct thread *td, void *tls_base)
284 td->td_pcb->pcb_regs.sf_tpidrurw = (register_t)tls_base;
288 td->td_md.md_tp = (register_t)tls_base;
289 if (td == curthread) {
291 *(register_t *)ARM_TP_ADDRESS = (register_t)tls_base;
299 cpu_thread_exit(struct thread *td)
304 cpu_thread_alloc(struct thread *td)
306 td->td_pcb = (struct pcb *)(td->td_kstack + td->td_kstack_pages *
309 * Ensure td_frame is aligned to an 8 byte boundary as it will be
310 * placed into the stack pointer which must be 8 byte aligned in
313 td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb) - 1;
316 #ifndef CPU_XSCALE_CORE3
317 pmap_use_minicache(td->td_kstack, td->td_kstack_pages * PAGE_SIZE);
323 cpu_thread_free(struct thread *td)
328 cpu_thread_clean(struct thread *td)
333 * Intercept the return address from a freshly forked process that has NOT
334 * been scheduled yet.
336 * This is needed to make kernel threads stay in kernel mode.
339 cpu_fork_kthread_handler(struct thread *td, void (*func)(void *), void *arg)
341 td->td_pcb->pcb_regs.sf_r4 = (register_t)func; /* function */
342 td->td_pcb->pcb_regs.sf_r5 = (register_t)arg; /* first arg */
346 * Software interrupt handler for queued VM system processing.
352 if (busdma_swi_pending)
357 cpu_exit(struct thread *td)