1 /*- 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 5 * All rights reserved. 6 * 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. 10 * 11 * Redistribution and use in source and binary :forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 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. 26 * 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 37 * SUCH DAMAGE. 38 * 39 * from: @(#)vm_machdep.c 7.3 (Berkeley) 5/13/91 40 * Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$ 41 */ 42 43 #include "opt_compat.h" 44 45 #include <sys/cdefs.h> 46 __FBSDID("$FreeBSD$"); 47 48 #include <sys/param.h> 49 #include <sys/systm.h> 50 #include <sys/kernel.h> 51 #include <sys/malloc.h> 52 #include <sys/mbuf.h> 53 #include <sys/proc.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> 59 60 #include <machine/cpu.h> 61 #include <machine/frame.h> 62 #include <machine/pcb.h> 63 #include <machine/sysarch.h> 64 #include <sys/lock.h> 65 #include <sys/mutex.h> 66 67 #include <vm/vm.h> 68 #include <vm/pmap.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> 75 #include <vm/uma.h> 76 #include <vm/uma_int.h> 77 78 #include <machine/md_var.h> 79 #include <machine/vfp.h> 80 81 /* 82 * struct switchframe and trapframe must both be a multiple of 8 83 * for correct stack alignment. 84 */ 85 _Static_assert((sizeof(struct switchframe) % 8) == 0, "Bad alignment"); 86 _Static_assert((sizeof(struct trapframe) % 8) == 0, "Bad alignment"); 87 88 uint32_t initial_fpscr = VFPSCR_DN | VFPSCR_FZ; 89 90 /* 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. 94 */ 95 void 96 cpu_fork(register struct thread *td1, register struct proc *p2, 97 struct thread *td2, int flags) 98 { 99 struct pcb *pcb2; 100 struct trapframe *tf; 101 struct mdproc *mdp2; 102 103 if ((flags & RFPROC) == 0) 104 return; 105 106 /* Point the pcb to the top of the stack */ 107 pcb2 = (struct pcb *) 108 (td2->td_kstack + td2->td_kstack_pages * PAGE_SIZE) - 1; 109 #ifdef __XSCALE__ 110 #ifndef CPU_XSCALE_CORE3 111 pmap_use_minicache(td2->td_kstack, td2->td_kstack_pages * PAGE_SIZE); 112 #endif 113 #endif 114 #ifdef VFP 115 /* Store actual state of VFP */ 116 if (curthread == td1) { 117 critical_enter(); 118 vfp_store(&td1->td_pcb->pcb_vfpstate, false); 119 critical_exit(); 120 } 121 #endif 122 td2->td_pcb = pcb2; 123 124 /* Clone td1's pcb */ 125 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2)); 126 127 /* Point to mdproc and then copy over td1's contents */ 128 mdp2 = &p2->p_md; 129 bcopy(&td1->td_proc->p_md, mdp2, sizeof(*mdp2)); 130 131 /* Point the frame to the stack in front of pcb and copy td1's frame */ 132 td2->td_frame = (struct trapframe *)pcb2 - 1; 133 *td2->td_frame = *td1->td_frame; 134 135 /* 136 * Create a new fresh stack for the new process. 137 * Copy the trap frame for the return to user mode as if from a 138 * syscall. This copies most of the user mode register values. 139 */ 140 pmap_set_pcb_pagedir(vmspace_pmap(p2->p_vmspace), pcb2); 141 pcb2->pcb_regs.sf_r4 = (register_t)fork_return; 142 pcb2->pcb_regs.sf_r5 = (register_t)td2; 143 pcb2->pcb_regs.sf_lr = (register_t)fork_trampoline; 144 pcb2->pcb_regs.sf_sp = STACKALIGN(td2->td_frame); 145 #if __ARM_ARCH >= 6 146 pcb2->pcb_regs.sf_tpidrurw = (register_t)get_tls(); 147 #endif 148 149 pcb2->pcb_vfpcpu = -1; 150 pcb2->pcb_vfpstate.fpscr = initial_fpscr; 151 152 tf = td2->td_frame; 153 tf->tf_spsr &= ~PSR_C; 154 tf->tf_r0 = 0; 155 tf->tf_r1 = 0; 156 157 158 /* Setup to release spin count in fork_exit(). */ 159 td2->td_md.md_spinlock_count = 1; 160 td2->td_md.md_saved_cspr = PSR_SVC32_MODE; 161 #if __ARM_ARCH < 6 162 td2->td_md.md_tp = *(register_t *)ARM_TP_ADDRESS; 163 #endif 164 } 165 166 void 167 cpu_thread_swapin(struct thread *td) 168 { 169 } 170 171 void 172 cpu_thread_swapout(struct thread *td) 173 { 174 } 175 176 void 177 cpu_set_syscall_retval(struct thread *td, int error) 178 { 179 struct trapframe *frame; 180 int fixup; 181 #ifdef __ARMEB__ 182 u_int call; 183 #endif 184 185 frame = td->td_frame; 186 fixup = 0; 187 188 #ifdef __ARMEB__ 189 /* 190 * __syscall returns an off_t while most other syscalls return an 191 * int. As an off_t is 64-bits and an int is 32-bits we need to 192 * place the returned data into r1. As the lseek and freebsd6_lseek 193 * syscalls also return an off_t they do not need this fixup. 194 */ 195 call = frame->tf_r7; 196 if (call == SYS___syscall) { 197 register_t *ap = &frame->tf_r0; 198 register_t code = ap[_QUAD_LOWWORD]; 199 if (td->td_proc->p_sysent->sv_mask) 200 code &= td->td_proc->p_sysent->sv_mask; 201 fixup = (code != SYS_lseek); 202 } 203 #endif 204 205 switch (error) { 206 case 0: 207 if (fixup) { 208 frame->tf_r0 = 0; 209 frame->tf_r1 = td->td_retval[0]; 210 } else { 211 frame->tf_r0 = td->td_retval[0]; 212 frame->tf_r1 = td->td_retval[1]; 213 } 214 frame->tf_spsr &= ~PSR_C; /* carry bit */ 215 break; 216 case ERESTART: 217 /* 218 * Reconstruct the pc to point at the swi. 219 */ 220 #if __ARM_ARCH >= 7 221 if ((frame->tf_spsr & PSR_T) != 0) 222 frame->tf_pc -= THUMB_INSN_SIZE; 223 else 224 #endif 225 frame->tf_pc -= INSN_SIZE; 226 break; 227 case EJUSTRETURN: 228 /* nothing to do */ 229 break; 230 default: 231 frame->tf_r0 = SV_ABI_ERRNO(td->td_proc, error); 232 frame->tf_spsr |= PSR_C; /* carry bit */ 233 break; 234 } 235 } 236 237 /* 238 * Initialize machine state, mostly pcb and trap frame for a new 239 * thread, about to return to userspace. Put enough state in the new 240 * thread's PCB to get it to go back to the fork_return(), which 241 * finalizes the thread state and handles peculiarities of the first 242 * return to userspace for the new thread. 243 */ 244 void 245 cpu_copy_thread(struct thread *td, struct thread *td0) 246 { 247 248 bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe)); 249 bcopy(td0->td_pcb, td->td_pcb, sizeof(struct pcb)); 250 251 td->td_pcb->pcb_regs.sf_r4 = (register_t)fork_return; 252 td->td_pcb->pcb_regs.sf_r5 = (register_t)td; 253 td->td_pcb->pcb_regs.sf_lr = (register_t)fork_trampoline; 254 td->td_pcb->pcb_regs.sf_sp = STACKALIGN(td->td_frame); 255 256 td->td_frame->tf_spsr &= ~PSR_C; 257 td->td_frame->tf_r0 = 0; 258 259 /* Setup to release spin count in fork_exit(). */ 260 td->td_md.md_spinlock_count = 1; 261 td->td_md.md_saved_cspr = PSR_SVC32_MODE; 262 } 263 264 /* 265 * Set that machine state for performing an upcall that starts 266 * the entry function with the given argument. 267 */ 268 void 269 cpu_set_upcall(struct thread *td, void (*entry)(void *), void *arg, 270 stack_t *stack) 271 { 272 struct trapframe *tf = td->td_frame; 273 274 tf->tf_usr_sp = STACKALIGN((int)stack->ss_sp + stack->ss_size); 275 tf->tf_pc = (int)entry; 276 tf->tf_r0 = (int)arg; 277 tf->tf_spsr = PSR_USR32_MODE; 278 } 279 280 int 281 cpu_set_user_tls(struct thread *td, void *tls_base) 282 { 283 284 #if __ARM_ARCH >= 6 285 td->td_pcb->pcb_regs.sf_tpidrurw = (register_t)tls_base; 286 if (td == curthread) 287 set_tls(tls_base); 288 #else 289 td->td_md.md_tp = (register_t)tls_base; 290 if (td == curthread) { 291 critical_enter(); 292 *(register_t *)ARM_TP_ADDRESS = (register_t)tls_base; 293 critical_exit(); 294 } 295 #endif 296 return (0); 297 } 298 299 void 300 cpu_thread_exit(struct thread *td) 301 { 302 } 303 304 void 305 cpu_thread_alloc(struct thread *td) 306 { 307 td->td_pcb = (struct pcb *)(td->td_kstack + td->td_kstack_pages * 308 PAGE_SIZE) - 1; 309 /* 310 * Ensure td_frame is aligned to an 8 byte boundary as it will be 311 * placed into the stack pointer which must be 8 byte aligned in 312 * the ARM EABI. 313 */ 314 td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb) - 1; 315 316 #ifdef __XSCALE__ 317 #ifndef CPU_XSCALE_CORE3 318 pmap_use_minicache(td->td_kstack, td->td_kstack_pages * PAGE_SIZE); 319 #endif 320 #endif 321 } 322 323 void 324 cpu_thread_free(struct thread *td) 325 { 326 } 327 328 void 329 cpu_thread_clean(struct thread *td) 330 { 331 } 332 333 /* 334 * Intercept the return address from a freshly forked process that has NOT 335 * been scheduled yet. 336 * 337 * This is needed to make kernel threads stay in kernel mode. 338 */ 339 void 340 cpu_fork_kthread_handler(struct thread *td, void (*func)(void *), void *arg) 341 { 342 td->td_pcb->pcb_regs.sf_r4 = (register_t)func; /* function */ 343 td->td_pcb->pcb_regs.sf_r5 = (register_t)arg; /* first arg */ 344 } 345 346 /* 347 * Software interrupt handler for queued VM system processing. 348 */ 349 void 350 swi_vm(void *dummy) 351 { 352 353 if (busdma_swi_pending) 354 busdma_swi(); 355 } 356 357 void 358 cpu_exit(struct thread *td) 359 { 360 } 361 362