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(struct thread *td1, struct proc *p2, struct thread *td2, int flags) 97 { 98 struct pcb *pcb2; 99 struct trapframe *tf; 100 struct mdproc *mdp2; 101 102 if ((flags & RFPROC) == 0) 103 return; 104 105 /* Point the pcb to the top of the stack */ 106 pcb2 = (struct pcb *) 107 (td2->td_kstack + td2->td_kstack_pages * PAGE_SIZE) - 1; 108 #ifdef __XSCALE__ 109 #ifndef CPU_XSCALE_CORE3 110 pmap_use_minicache(td2->td_kstack, td2->td_kstack_pages * PAGE_SIZE); 111 #endif 112 #endif 113 #ifdef VFP 114 /* Store actual state of VFP */ 115 if (curthread == td1) { 116 critical_enter(); 117 vfp_store(&td1->td_pcb->pcb_vfpstate, false); 118 critical_exit(); 119 } 120 #endif 121 td2->td_pcb = pcb2; 122 123 /* Clone td1's pcb */ 124 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2)); 125 126 /* Point to mdproc and then copy over td1's contents */ 127 mdp2 = &p2->p_md; 128 bcopy(&td1->td_proc->p_md, mdp2, sizeof(*mdp2)); 129 130 /* 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; 133 134 /* 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. 138 */ 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); 144 #if __ARM_ARCH >= 6 145 pcb2->pcb_regs.sf_tpidrurw = (register_t)get_tls(); 146 #endif 147 148 pcb2->pcb_vfpcpu = -1; 149 pcb2->pcb_vfpstate.fpscr = initial_fpscr; 150 151 tf = td2->td_frame; 152 tf->tf_spsr &= ~PSR_C; 153 tf->tf_r0 = 0; 154 tf->tf_r1 = 0; 155 156 157 /* 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; 160 #if __ARM_ARCH < 6 161 td2->td_md.md_tp = *(register_t *)ARM_TP_ADDRESS; 162 #endif 163 } 164 165 void 166 cpu_thread_swapin(struct thread *td) 167 { 168 } 169 170 void 171 cpu_thread_swapout(struct thread *td) 172 { 173 } 174 175 void 176 cpu_set_syscall_retval(struct thread *td, int error) 177 { 178 struct trapframe *frame; 179 int fixup; 180 #ifdef __ARMEB__ 181 u_int call; 182 #endif 183 184 frame = td->td_frame; 185 fixup = 0; 186 187 #ifdef __ARMEB__ 188 /* 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. 193 */ 194 call = frame->tf_r7; 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); 201 } 202 #endif 203 204 switch (error) { 205 case 0: 206 if (fixup) { 207 frame->tf_r0 = 0; 208 frame->tf_r1 = td->td_retval[0]; 209 } else { 210 frame->tf_r0 = td->td_retval[0]; 211 frame->tf_r1 = td->td_retval[1]; 212 } 213 frame->tf_spsr &= ~PSR_C; /* carry bit */ 214 break; 215 case ERESTART: 216 /* 217 * Reconstruct the pc to point at the swi. 218 */ 219 #if __ARM_ARCH >= 7 220 if ((frame->tf_spsr & PSR_T) != 0) 221 frame->tf_pc -= THUMB_INSN_SIZE; 222 else 223 #endif 224 frame->tf_pc -= INSN_SIZE; 225 break; 226 case EJUSTRETURN: 227 /* nothing to do */ 228 break; 229 default: 230 frame->tf_r0 = SV_ABI_ERRNO(td->td_proc, error); 231 frame->tf_spsr |= PSR_C; /* carry bit */ 232 break; 233 } 234 } 235 236 /* 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. 242 */ 243 void 244 cpu_copy_thread(struct thread *td, struct thread *td0) 245 { 246 247 bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe)); 248 bcopy(td0->td_pcb, td->td_pcb, sizeof(struct pcb)); 249 250 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); 254 255 td->td_frame->tf_spsr &= ~PSR_C; 256 td->td_frame->tf_r0 = 0; 257 258 /* 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; 261 } 262 263 /* 264 * Set that machine state for performing an upcall that starts 265 * the entry function with the given argument. 266 */ 267 void 268 cpu_set_upcall(struct thread *td, void (*entry)(void *), void *arg, 269 stack_t *stack) 270 { 271 struct trapframe *tf = td->td_frame; 272 273 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; 277 } 278 279 int 280 cpu_set_user_tls(struct thread *td, void *tls_base) 281 { 282 283 #if __ARM_ARCH >= 6 284 td->td_pcb->pcb_regs.sf_tpidrurw = (register_t)tls_base; 285 if (td == curthread) 286 set_tls(tls_base); 287 #else 288 td->td_md.md_tp = (register_t)tls_base; 289 if (td == curthread) { 290 critical_enter(); 291 *(register_t *)ARM_TP_ADDRESS = (register_t)tls_base; 292 critical_exit(); 293 } 294 #endif 295 return (0); 296 } 297 298 void 299 cpu_thread_exit(struct thread *td) 300 { 301 } 302 303 void 304 cpu_thread_alloc(struct thread *td) 305 { 306 td->td_pcb = (struct pcb *)(td->td_kstack + td->td_kstack_pages * 307 PAGE_SIZE) - 1; 308 /* 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 311 * the ARM EABI. 312 */ 313 td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb) - 1; 314 315 #ifdef __XSCALE__ 316 #ifndef CPU_XSCALE_CORE3 317 pmap_use_minicache(td->td_kstack, td->td_kstack_pages * PAGE_SIZE); 318 #endif 319 #endif 320 } 321 322 void 323 cpu_thread_free(struct thread *td) 324 { 325 } 326 327 void 328 cpu_thread_clean(struct thread *td) 329 { 330 } 331 332 /* 333 * Intercept the return address from a freshly forked process that has NOT 334 * been scheduled yet. 335 * 336 * This is needed to make kernel threads stay in kernel mode. 337 */ 338 void 339 cpu_fork_kthread_handler(struct thread *td, void (*func)(void *), void *arg) 340 { 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 */ 343 } 344 345 /* 346 * Software interrupt handler for queued VM system processing. 347 */ 348 void 349 swi_vm(void *dummy) 350 { 351 352 if (busdma_swi_pending) 353 busdma_swi(); 354 } 355 356 void 357 cpu_exit(struct thread *td) 358 { 359 } 360 361