1 /*- 2 * Copyright (c) 2014 Andrew Turner 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 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. 13 * 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 24 * SUCH DAMAGE. 25 * 26 */ 27 28 #include "opt_platform.h" 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/limits.h> 36 #include <sys/proc.h> 37 #include <sys/sf_buf.h> 38 #include <sys/signal.h> 39 #include <sys/sysent.h> 40 #include <sys/unistd.h> 41 42 #include <vm/vm.h> 43 #include <vm/vm_page.h> 44 #include <vm/vm_map.h> 45 #include <vm/uma.h> 46 #include <vm/uma_int.h> 47 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> 53 54 #ifdef VFP 55 #include <machine/vfp.h> 56 #endif 57 58 #include <dev/psci/psci.h> 59 60 /* 61 * Finish a fork operation, with process p2 nearly set up. 62 * Copy and update the pcb, set up the stack so that the child 63 * ready to run and return to user mode. 64 */ 65 void 66 cpu_fork(struct thread *td1, struct proc *p2, struct thread *td2, int flags) 67 { 68 struct pcb *pcb2; 69 struct trapframe *tf; 70 71 if ((flags & RFPROC) == 0) 72 return; 73 74 if (td1 == curthread) { 75 /* 76 * Save the tpidr_el0 and the vfp state, these normally happen 77 * in cpu_switch, but if userland changes these then forks 78 * this may not have happened. 79 */ 80 td1->td_pcb->pcb_tpidr_el0 = READ_SPECIALREG(tpidr_el0); 81 td1->td_pcb->pcb_tpidrro_el0 = READ_SPECIALREG(tpidrro_el0); 82 #ifdef VFP 83 if ((td1->td_pcb->pcb_fpflags & PCB_FP_STARTED) != 0) 84 vfp_save_state(td1, td1->td_pcb); 85 #endif 86 } 87 88 pcb2 = (struct pcb *)(td2->td_kstack + 89 td2->td_kstack_pages * PAGE_SIZE) - 1; 90 91 td2->td_pcb = pcb2; 92 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2)); 93 94 tf = (struct trapframe *)STACKALIGN((struct trapframe *)pcb2 - 1); 95 bcopy(td1->td_frame, tf, sizeof(*tf)); 96 tf->tf_x[0] = 0; 97 tf->tf_x[1] = 0; 98 tf->tf_spsr = td1->td_frame->tf_spsr & (PSR_M_32 | PSR_DAIF); 99 100 td2->td_frame = tf; 101 102 /* Set the return value registers for fork() */ 103 td2->td_pcb->pcb_x[8] = (uintptr_t)fork_return; 104 td2->td_pcb->pcb_x[9] = (uintptr_t)td2; 105 td2->td_pcb->pcb_x[PCB_LR] = (uintptr_t)fork_trampoline; 106 td2->td_pcb->pcb_sp = (uintptr_t)td2->td_frame; 107 td2->td_pcb->pcb_fpusaved = &td2->td_pcb->pcb_fpustate; 108 td2->td_pcb->pcb_vfpcpu = UINT_MAX; 109 110 /* Setup to release spin count in fork_exit(). */ 111 td2->td_md.md_spinlock_count = 1; 112 td2->td_md.md_saved_daif = td1->td_md.md_saved_daif & ~DAIF_I_MASKED; 113 } 114 115 void 116 cpu_reset(void) 117 { 118 119 psci_reset(); 120 121 printf("cpu_reset failed"); 122 while(1) 123 __asm volatile("wfi" ::: "memory"); 124 } 125 126 void 127 cpu_thread_swapin(struct thread *td) 128 { 129 } 130 131 void 132 cpu_thread_swapout(struct thread *td) 133 { 134 } 135 136 void 137 cpu_set_syscall_retval(struct thread *td, int error) 138 { 139 struct trapframe *frame; 140 141 frame = td->td_frame; 142 143 switch (error) { 144 case 0: 145 frame->tf_x[0] = td->td_retval[0]; 146 frame->tf_x[1] = td->td_retval[1]; 147 frame->tf_spsr &= ~PSR_C; /* carry bit */ 148 break; 149 case ERESTART: 150 frame->tf_elr -= 4; 151 break; 152 case EJUSTRETURN: 153 break; 154 default: 155 frame->tf_spsr |= PSR_C; /* carry bit */ 156 frame->tf_x[0] = SV_ABI_ERRNO(td->td_proc, error); 157 break; 158 } 159 } 160 161 /* 162 * Initialize machine state, mostly pcb and trap frame for a new 163 * thread, about to return to userspace. Put enough state in the new 164 * thread's PCB to get it to go back to the fork_return(), which 165 * finalizes the thread state and handles peculiarities of the first 166 * return to userspace for the new thread. 167 */ 168 void 169 cpu_copy_thread(struct thread *td, struct thread *td0) 170 { 171 bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe)); 172 bcopy(td0->td_pcb, td->td_pcb, sizeof(struct pcb)); 173 174 td->td_pcb->pcb_x[8] = (uintptr_t)fork_return; 175 td->td_pcb->pcb_x[9] = (uintptr_t)td; 176 td->td_pcb->pcb_x[PCB_LR] = (uintptr_t)fork_trampoline; 177 td->td_pcb->pcb_sp = (uintptr_t)td->td_frame; 178 td->td_pcb->pcb_fpusaved = &td->td_pcb->pcb_fpustate; 179 td->td_pcb->pcb_vfpcpu = UINT_MAX; 180 181 /* Setup to release spin count in fork_exit(). */ 182 td->td_md.md_spinlock_count = 1; 183 td->td_md.md_saved_daif = td0->td_md.md_saved_daif & ~DAIF_I_MASKED; 184 } 185 186 /* 187 * Set that machine state for performing an upcall that starts 188 * the entry function with the given argument. 189 */ 190 void 191 cpu_set_upcall(struct thread *td, void (*entry)(void *), void *arg, 192 stack_t *stack) 193 { 194 struct trapframe *tf = td->td_frame; 195 196 /* 32bits processes use r13 for sp */ 197 if (td->td_frame->tf_spsr & PSR_M_32) 198 tf->tf_x[13] = STACKALIGN((uintptr_t)stack->ss_sp + stack->ss_size); 199 else 200 tf->tf_sp = STACKALIGN((uintptr_t)stack->ss_sp + stack->ss_size); 201 tf->tf_elr = (register_t)entry; 202 tf->tf_x[0] = (register_t)arg; 203 } 204 205 int 206 cpu_set_user_tls(struct thread *td, void *tls_base) 207 { 208 struct pcb *pcb; 209 210 if ((uintptr_t)tls_base >= VM_MAXUSER_ADDRESS) 211 return (EINVAL); 212 213 pcb = td->td_pcb; 214 if (td->td_frame->tf_spsr & PSR_M_32) { 215 /* 32bits arm stores the user TLS into tpidrro */ 216 pcb->pcb_tpidrro_el0 = (register_t)tls_base; 217 pcb->pcb_tpidr_el0 = (register_t)tls_base; 218 if (td == curthread) { 219 WRITE_SPECIALREG(tpidrro_el0, tls_base); 220 WRITE_SPECIALREG(tpidr_el0, tls_base); 221 } 222 } else { 223 pcb->pcb_tpidr_el0 = (register_t)tls_base; 224 if (td == curthread) 225 WRITE_SPECIALREG(tpidr_el0, tls_base); 226 } 227 228 return (0); 229 } 230 231 void 232 cpu_thread_exit(struct thread *td) 233 { 234 } 235 236 void 237 cpu_thread_alloc(struct thread *td) 238 { 239 240 td->td_pcb = (struct pcb *)(td->td_kstack + 241 td->td_kstack_pages * PAGE_SIZE) - 1; 242 td->td_frame = (struct trapframe *)STACKALIGN( 243 (struct trapframe *)td->td_pcb - 1); 244 } 245 246 void 247 cpu_thread_free(struct thread *td) 248 { 249 } 250 251 void 252 cpu_thread_clean(struct thread *td) 253 { 254 } 255 256 /* 257 * Intercept the return address from a freshly forked process that has NOT 258 * been scheduled yet. 259 * 260 * This is needed to make kernel threads stay in kernel mode. 261 */ 262 void 263 cpu_fork_kthread_handler(struct thread *td, void (*func)(void *), void *arg) 264 { 265 266 td->td_pcb->pcb_x[8] = (uintptr_t)func; 267 td->td_pcb->pcb_x[9] = (uintptr_t)arg; 268 td->td_pcb->pcb_x[PCB_LR] = (uintptr_t)fork_trampoline; 269 td->td_pcb->pcb_sp = (uintptr_t)td->td_frame; 270 td->td_pcb->pcb_fpusaved = &td->td_pcb->pcb_fpustate; 271 td->td_pcb->pcb_vfpcpu = UINT_MAX; 272 } 273 274 void 275 cpu_exit(struct thread *td) 276 { 277 } 278 279 bool 280 cpu_exec_vmspace_reuse(struct proc *p __unused, vm_map_t map __unused) 281 { 282 283 return (true); 284 } 285 286 int 287 cpu_procctl(struct thread *td __unused, int idtype __unused, id_t id __unused, 288 int com __unused, void *data __unused) 289 { 290 291 return (EINVAL); 292 } 293 294 void 295 swi_vm(void *v) 296 { 297 298 if (busdma_swi_pending != 0) 299 busdma_swi(); 300 } 301