2 * Copyright (c) 2014 Andrew Turner
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
28 #include "opt_platform.h"
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/limits.h>
37 #include <sys/sf_buf.h>
38 #include <sys/signal.h>
39 #include <sys/sysent.h>
40 #include <sys/unistd.h>
43 #include <vm/vm_page.h>
44 #include <vm/vm_map.h>
46 #include <vm/uma_int.h>
48 #include <machine/armreg.h>
49 #include <machine/cpu.h>
50 #include <machine/md_var.h>
51 #include <machine/pcb.h>
52 #include <machine/frame.h>
55 #include <machine/vfp.h>
58 uint32_t initial_fpcr = VFPCR_DN;
60 #include <dev/psci/psci.h>
63 * Finish a fork operation, with process p2 nearly set up.
64 * Copy and update the pcb, set up the stack so that the child
65 * ready to run and return to user mode.
68 cpu_fork(struct thread *td1, struct proc *p2, struct thread *td2, int flags)
73 if ((flags & RFPROC) == 0)
76 if (td1 == curthread) {
78 * Save the tpidr_el0 and the vfp state, these normally happen
79 * in cpu_switch, but if userland changes these then forks
80 * this may not have happened.
82 td1->td_pcb->pcb_tpidr_el0 = READ_SPECIALREG(tpidr_el0);
83 td1->td_pcb->pcb_tpidrro_el0 = READ_SPECIALREG(tpidrro_el0);
85 if ((td1->td_pcb->pcb_fpflags & PCB_FP_STARTED) != 0)
86 vfp_save_state(td1, td1->td_pcb);
90 pcb2 = (struct pcb *)(td2->td_kstack +
91 td2->td_kstack_pages * PAGE_SIZE) - 1;
94 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2));
96 /* Clear the debug register state. */
97 bzero(&pcb2->pcb_dbg_regs, sizeof(pcb2->pcb_dbg_regs));
99 tf = (struct trapframe *)STACKALIGN((struct trapframe *)pcb2 - 1);
100 bcopy(td1->td_frame, tf, sizeof(*tf));
103 tf->tf_spsr = td1->td_frame->tf_spsr & (PSR_M_32 | PSR_DAIF);
107 /* Set the return value registers for fork() */
108 td2->td_pcb->pcb_x[8] = (uintptr_t)fork_return;
109 td2->td_pcb->pcb_x[9] = (uintptr_t)td2;
110 td2->td_pcb->pcb_lr = (uintptr_t)fork_trampoline;
111 td2->td_pcb->pcb_sp = (uintptr_t)td2->td_frame;
112 td2->td_pcb->pcb_fpusaved = &td2->td_pcb->pcb_fpustate;
113 td2->td_pcb->pcb_vfpcpu = UINT_MAX;
115 /* Setup to release spin count in fork_exit(). */
116 td2->td_md.md_spinlock_count = 1;
117 td2->td_md.md_saved_daif = PSR_DAIF_DEFAULT;
119 #if defined(PERTHREAD_SSP)
120 /* Set the new canary */
121 arc4random_buf(&td2->td_md.md_canary, sizeof(td2->td_md.md_canary));
131 printf("cpu_reset failed");
133 __asm volatile("wfi" ::: "memory");
137 cpu_thread_swapin(struct thread *td)
142 cpu_thread_swapout(struct thread *td)
147 cpu_set_syscall_retval(struct thread *td, int error)
149 struct trapframe *frame;
151 frame = td->td_frame;
153 if (__predict_true(error == 0)) {
154 frame->tf_x[0] = td->td_retval[0];
155 frame->tf_x[1] = td->td_retval[1];
156 frame->tf_spsr &= ~PSR_C; /* carry bit */
167 frame->tf_spsr |= PSR_C; /* carry bit */
168 frame->tf_x[0] = error;
174 * Initialize machine state, mostly pcb and trap frame for a new
175 * thread, about to return to userspace. Put enough state in the new
176 * thread's PCB to get it to go back to the fork_return(), which
177 * finalizes the thread state and handles peculiarities of the first
178 * return to userspace for the new thread.
181 cpu_copy_thread(struct thread *td, struct thread *td0)
183 bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe));
184 bcopy(td0->td_pcb, td->td_pcb, sizeof(struct pcb));
186 td->td_pcb->pcb_x[8] = (uintptr_t)fork_return;
187 td->td_pcb->pcb_x[9] = (uintptr_t)td;
188 td->td_pcb->pcb_lr = (uintptr_t)fork_trampoline;
189 td->td_pcb->pcb_sp = (uintptr_t)td->td_frame;
190 td->td_pcb->pcb_fpflags &= ~(PCB_FP_STARTED | PCB_FP_KERN | PCB_FP_NOSAVE);
191 td->td_pcb->pcb_fpusaved = &td->td_pcb->pcb_fpustate;
192 td->td_pcb->pcb_vfpcpu = UINT_MAX;
194 /* Setup to release spin count in fork_exit(). */
195 td->td_md.md_spinlock_count = 1;
196 td->td_md.md_saved_daif = PSR_DAIF_DEFAULT;
198 #if defined(PERTHREAD_SSP)
199 /* Set the new canary */
200 arc4random_buf(&td->td_md.md_canary, sizeof(td->td_md.md_canary));
205 * Set that machine state for performing an upcall that starts
206 * the entry function with the given argument.
209 cpu_set_upcall(struct thread *td, void (*entry)(void *), void *arg,
212 struct trapframe *tf = td->td_frame;
214 /* 32bits processes use r13 for sp */
215 if (td->td_frame->tf_spsr & PSR_M_32)
216 tf->tf_x[13] = STACKALIGN((uintptr_t)stack->ss_sp + stack->ss_size);
218 tf->tf_sp = STACKALIGN((uintptr_t)stack->ss_sp + stack->ss_size);
219 tf->tf_elr = (register_t)entry;
220 tf->tf_x[0] = (register_t)arg;
224 cpu_set_user_tls(struct thread *td, void *tls_base)
228 if ((uintptr_t)tls_base >= VM_MAXUSER_ADDRESS)
232 if (td->td_frame->tf_spsr & PSR_M_32) {
233 /* 32bits arm stores the user TLS into tpidrro */
234 pcb->pcb_tpidrro_el0 = (register_t)tls_base;
235 pcb->pcb_tpidr_el0 = (register_t)tls_base;
236 if (td == curthread) {
237 WRITE_SPECIALREG(tpidrro_el0, tls_base);
238 WRITE_SPECIALREG(tpidr_el0, tls_base);
241 pcb->pcb_tpidr_el0 = (register_t)tls_base;
243 WRITE_SPECIALREG(tpidr_el0, tls_base);
250 cpu_thread_exit(struct thread *td)
255 cpu_thread_alloc(struct thread *td)
258 td->td_pcb = (struct pcb *)(td->td_kstack +
259 td->td_kstack_pages * PAGE_SIZE) - 1;
260 td->td_frame = (struct trapframe *)STACKALIGN(
261 (struct trapframe *)td->td_pcb - 1);
265 cpu_thread_free(struct thread *td)
270 cpu_thread_clean(struct thread *td)
275 * Intercept the return address from a freshly forked process that has NOT
276 * been scheduled yet.
278 * This is needed to make kernel threads stay in kernel mode.
281 cpu_fork_kthread_handler(struct thread *td, void (*func)(void *), void *arg)
284 td->td_pcb->pcb_x[8] = (uintptr_t)func;
285 td->td_pcb->pcb_x[9] = (uintptr_t)arg;
289 cpu_exit(struct thread *td)
294 cpu_exec_vmspace_reuse(struct proc *p __unused, vm_map_t map __unused)
301 cpu_procctl(struct thread *td __unused, int idtype __unused, id_t id __unused,
302 int com __unused, void *data __unused)