arch/arm64/kernel/process.c

   1 /*
   2  * Based on arch/arm/kernel/process.c
   3  *
   4  * Original Copyright (C) 1995  Linus Torvalds
   5  * Copyright (C) 1996-2000 Russell King - Converted to ARM.
   6  * Copyright (C) 2012 ARM Ltd.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <stdarg.h>
  22
  23 #include <linux/compat.h>
  24 #include <linux/export.h>
  25 #include <linux/sched.h>
  26 #include <linux/kernel.h>
  27 #include <linux/mm.h>
  28 #include <linux/stddef.h>
  29 #include <linux/unistd.h>
  30 #include <linux/user.h>
  31 #include <linux/delay.h>
  32 #include <linux/reboot.h>
  33 #include <linux/interrupt.h>
  34 #include <linux/kallsyms.h>
  35 #include <linux/init.h>
  36 #include <linux/cpu.h>
  37 #include <linux/elfcore.h>
  38 #include <linux/pm.h>
  39 #include <linux/tick.h>
  40 #include <linux/utsname.h>
  41 #include <linux/uaccess.h>
  42 #include <linux/random.h>
  43 #include <linux/hw_breakpoint.h>
  44 #include <linux/cpuidle.h>
  45 #include <linux/leds.h>
  46 #include <linux/personality.h>
  47 #include <linux/notifier.h>
  48 #include <linux/mtk_ram_console.h>
  49
  50 #include <asm/compat.h>
  51 #include <asm/cacheflush.h>
  52 #include <asm/fpsimd.h>
  53 #include <asm/mmu_context.h>
  54 #include <asm/processor.h>
  55 #include <asm/stacktrace.h>
  56
  57 extern void arch_reset(char mode, const char *cmd);
  58
  59 static void setup_restart(void)
  60 {
  61         /*
  62          * Tell the mm system that we are going to reboot -
  63          * we may need it to insert some 1:1 mappings so that
  64          * soft boot works.
  65          */
  66         setup_mm_for_reboot();
  67
  68         /* Clean and invalidate caches */
  69         flush_cache_all();
  70
  71         /* Turn D-cache off */
  72         cpu_cache_off();
  73
  74         /* Push out any further dirty data, and ensure cache is empty */
  75         flush_cache_all();
  76 }
  77
  78 void soft_restart(unsigned long addr)
  79 {
  80         setup_restart();
  81         cpu_reset(addr);
  82 }
  83
  84 /*
  85  * Function pointers to optional machine specific functions
  86  */
  87 void (*pm_power_off)(void);
  88 EXPORT_SYMBOL_GPL(pm_power_off);
  89
  90 void (*arm_pm_restart)(char str, const char *cmd);
  91 EXPORT_SYMBOL_GPL(arm_pm_restart);
  92
  93 /*
  94  * This is our default idle handler.
  95  */
  96
  97 void (*arm_pm_idle)(void);
  98
  99 static void default_idle(void)
 100 {
 101         if (arm_pm_idle)
 102                 arm_pm_idle();
 103         else
 104                 cpu_do_idle();
 105         local_irq_enable();
 106 }
 107
 108 void arch_cpu_idle_prepare(void)
 109 {
 110         local_fiq_enable();
 111 }
 112
 113 void arch_cpu_idle_enter(void)
 114 {
 115         idle_notifier_call_chain(IDLE_START);
 116         ledtrig_cpu(CPU_LED_IDLE_START);
 117 #ifdef CONFIG_PL310_ERRATA_769419
 118         wmb();
 119 #endif
 120 }
 121
 122 void arch_cpu_idle_exit(void)
 123 {
 124         ledtrig_cpu(CPU_LED_IDLE_END);
 125         idle_notifier_call_chain(IDLE_END);
 126 }
 127
 128 #ifdef CONFIG_HOTPLUG_CPU
 129 void arch_cpu_idle_dead(void)
 130 {
 131        cpu_die();
 132 }
 133 #endif
 134
 135 /*
 136  * Called from the core idle loop.
 137  */
 138 void arch_cpu_idle(void)
 139 {
 140         if (cpuidle_idle_call())
 141                 default_idle();
 142 }
 143
 144 void machine_shutdown(void)
 145 {
 146 #ifdef CONFIG_SMP
 147         smp_send_stop();
 148 #endif
 149 }
 150
 151 void machine_halt(void)
 152 {
 153         machine_shutdown();
 154         while (1);
 155 }
 156
 157 extern int reboot_pid;
 158 //static int reboot_pid = 0;
 159
 160 void machine_power_off(void)
 161 {
 162         struct task_struct *tsk;
 163         /* Disable interrupts first */
 164         local_irq_disable();
 165         local_fiq_disable();
 166
 167         machine_shutdown();
 168         if(reboot_pid > 1)
 169         {
 170                 tsk = find_task_by_vpid(reboot_pid);
 171                 if(tsk == NULL)
 172                         tsk = current;
 173                 dump_stack();
 174         }
 175         else
 176         {
 177                 tsk = current;
 178         }
 179
 180         if(tsk->real_parent)
 181         {
 182          if(tsk->real_parent->real_parent)
 183          {
 184            printk("machine_shutdown: start, Proess(%s:%d). father %s:%d. grandfather %s:%d.\n",
 185                 tsk->comm, tsk->pid,tsk->real_parent->comm,tsk->real_parent->pid,
 186                 tsk->real_parent->real_parent->comm,tsk->real_parent->real_parent->pid);
 187          }
 188          else
 189          {
 190            printk("machine_shutdown: start, Proess(%s:%d). father %s:%d.\n",
 191                 tsk->comm, tsk->pid,tsk->real_parent->comm,tsk->real_parent->pid);
 192          }
 193         }
 194         else
 195         {
 196           printk("machine_shutdown: start, Proess(%s:%d)\n", tsk->comm, tsk->pid);
 197         }
 198
 199 #ifdef CONFIG_MTK_EMMC_SUPPORT
 200         last_kmsg_store_to_emmc();
 201 #endif
 202         if (pm_power_off)
 203                 pm_power_off();
 204 }
 205
 206 void machine_restart(char *cmd)
 207 {
 208         struct task_struct *tsk;
 209
 210         /* Disable interrupts first */
 211         local_irq_disable();
 212         local_fiq_disable();
 213
 214         machine_shutdown();
 215
 216         if(reboot_pid > 1)
 217         {
 218                 tsk = find_task_by_vpid(reboot_pid);
 219                 if(tsk == NULL)
 220                         tsk = current;
 221                 dump_stack();
 222         }
 223         else
 224         {
 225                 tsk = current;
 226         }
 227
 228         if(tsk->real_parent)
 229         {
 230          if(tsk->real_parent->real_parent)
 231          {
 232            printk("machine_shutdown: start, Proess(%s:%d). father %s:%d. grandfather %s:%d.\n",
 233                 tsk->comm, tsk->pid,tsk->real_parent->comm,tsk->real_parent->pid,
 234                 tsk->real_parent->real_parent->comm,tsk->real_parent->real_parent->pid);
 235          }
 236          else
 237          {
 238            printk("machine_shutdown: start, Proess(%s:%d). father %s:%d.\n",
 239                 tsk->comm, tsk->pid,tsk->real_parent->comm,tsk->real_parent->pid);
 240          }
 241         }
 242         else
 243         {
 244           printk("machine_shutdown: start, Proess(%s:%d)\n", tsk->comm, tsk->pid);
 245         }
 246
 247         /* Now call the architecture specific reboot code. */
 248         if (arm_pm_restart)
 249                 arm_pm_restart('h', cmd);
 250 #ifndef CONFIG_MTK_FPGA
 251         else
 252                 arch_reset('h', cmd);
 253 #endif
 254         /*
 255          * Whoops - the architecture was unable to reboot.
 256          */
 257         printk("Reboot failed -- System halted\n");
 258         while (1);
 259 }
 260
 261 /*
 262  * dump a block of kernel memory from around the given address
 263  */
 264 static void show_data(unsigned long addr, int nbytes, const char *name)
 265 {
 266         int     i, j;
 267         int     nlines;
 268         u32     *p;
 269
 270         /*
 271          * don't attempt to dump non-kernel addresses or
 272          * values that are probably just small negative numbers
 273          */
 274         if (addr < PAGE_OFFSET || addr > -256UL)
 275                 return;
 276
 277         printk("\n%s: %#lx:\n", name, addr);
 278
 279         /*
 280          * round address down to a 32 bit boundary
 281          * and always dump a multiple of 32 bytes
 282          */
 283         p = (u32 *)(addr & ~(sizeof(u32) - 1));
 284         nbytes += (addr & (sizeof(u32) - 1));
 285         nlines = (nbytes + 31) / 32;
 286
 287
 288         for (i = 0; i < nlines; i++) {
 289                 /*
 290                  * just display low 16 bits of address to keep
 291                  * each line of the dump < 80 characters
 292                  */
 293                 printk("%04lx ", (unsigned long)p & 0xffff);
 294                 for (j = 0; j < 8; j++) {
 295                         u32     data;
 296                         if (probe_kernel_address(p, data)) {
 297                                 printk(" ********");
 298                         } else {
 299                                 printk(" %08x", data);
 300                         }
 301                         ++p;
 302                 }
 303                 printk("\n");
 304         }
 305 }
 306
 307 static void show_extra_register_data(struct pt_regs *regs, int nbytes)
 308 {
 309         mm_segment_t fs;
 310         unsigned int i;
 311
 312         fs = get_fs();
 313         set_fs(KERNEL_DS);
 314         show_data(regs->pc - nbytes, nbytes * 2, "PC");
 315         show_data(regs->regs[30] - nbytes, nbytes * 2, "LR");
 316         show_data(regs->sp - nbytes, nbytes * 2, "SP");
 317         for (i = 0; i < 30; i++) {
 318                 char name[4];
 319                 snprintf(name, sizeof(name), "X%u", i);
 320                 show_data(regs->regs[i] - nbytes, nbytes * 2, name);
 321         }
 322         set_fs(fs);
 323 }
 324
 325 void __show_regs(struct pt_regs *regs)
 326 {
 327         int i;
 328
 329         show_regs_print_info(KERN_DEFAULT);
 330         print_symbol("PC is at %s\n", instruction_pointer(regs));
 331         print_symbol("LR is at %s\n", regs->regs[30]);
 332         printk("pc : [<%016llx>] lr : [<%016llx>] pstate: %08llx\n",
 333                regs->pc, regs->regs[30], regs->pstate);
 334         printk("sp : %016llx\n", regs->sp);
 335         for (i = 29; i >= 0; i--) {
 336                 printk("x%-2d: %016llx ", i, regs->regs[i]);
 337                 if (i % 2 == 0)
 338                         printk("\n");
 339         }
 340         if (!user_mode(regs))
 341                 show_extra_register_data(regs, 128);
 342         printk("\n");
 343 }
 344
 345 void show_regs(struct pt_regs * regs)
 346 {
 347         printk("\n");
 348         __show_regs(regs);
 349 }
 350
 351 /*
 352  * Free current thread data structures etc..
 353  */
 354 void exit_thread(void)
 355 {
 356 }
 357
 358 void flush_thread(void)
 359 {
 360         fpsimd_flush_thread();
 361         flush_ptrace_hw_breakpoint(current);
 362 }
 363
 364 void release_thread(struct task_struct *dead_task)
 365 {
 366 }
 367
 368 int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
 369 {
 370         fpsimd_preserve_current_state();
 371         *dst = *src;
 372         return 0;
 373 }
 374
 375 asmlinkage void ret_from_fork(void) asm("ret_from_fork");
 376
 377 int copy_thread(unsigned long clone_flags, unsigned long stack_start,
 378                 unsigned long stk_sz, struct task_struct *p)
 379 {
 380         struct pt_regs *childregs = task_pt_regs(p);
 381         unsigned long tls = p->thread.tp_value;
 382
 383         memset(&p->thread.cpu_context, 0, sizeof(struct cpu_context));
 384
 385         if (likely(!(p->flags & PF_KTHREAD))) {
 386                 *childregs = *current_pt_regs();
 387                 childregs->regs[0] = 0;
 388                 if (is_compat_thread(task_thread_info(p))) {
 389                         if (stack_start)
 390                                 childregs->compat_sp = stack_start;
 391                 } else {
 392                         /*
 393                          * Read the current TLS pointer from tpidr_el0 as it may be
 394                          * out-of-sync with the saved value.
 395                          */
 396                         asm("mrs %0, tpidr_el0" : "=r" (tls));
 397                         if (stack_start) {
 398                                 /* 16-byte aligned stack mandatory on AArch64 */
 399                                 if (stack_start & 15)
 400                                         return -EINVAL;
 401                                 childregs->sp = stack_start;
 402                         }
 403                 }
 404                 /*
 405                  * If a TLS pointer was passed to clone (4th argument), use it
 406                  * for the new thread.
 407                  */
 408                 if (clone_flags & CLONE_SETTLS)
 409                         tls = childregs->regs[3];
 410         } else {
 411                 memset(childregs, 0, sizeof(struct pt_regs));
 412                 childregs->pstate = PSR_MODE_EL1h;
 413                 p->thread.cpu_context.x19 = stack_start;
 414                 p->thread.cpu_context.x20 = stk_sz;
 415         }
 416         p->thread.cpu_context.pc = (unsigned long)ret_from_fork;
 417         p->thread.cpu_context.sp = (unsigned long)childregs;
 418         p->thread.tp_value = tls;
 419
 420         ptrace_hw_copy_thread(p);
 421
 422         return 0;
 423 }
 424
 425 static void tls_thread_switch(struct task_struct *next)
 426 {
 427         unsigned long tpidr, tpidrro;
 428
 429         if (!is_compat_task()) {
 430                 asm("mrs %0, tpidr_el0" : "=r" (tpidr));
 431                 current->thread.tp_value = tpidr;
 432         }
 433
 434         if (is_compat_thread(task_thread_info(next))) {
 435                 tpidr = 0;
 436                 tpidrro = next->thread.tp_value;
 437         } else {
 438                 tpidr = next->thread.tp_value;
 439                 tpidrro = 0;
 440         }
 441
 442         asm(
 443         "       msr     tpidr_el0, %0\n"
 444         "       msr     tpidrro_el0, %1"
 445         : : "r" (tpidr), "r" (tpidrro));
 446 }
 447
 448 /*
 449  * Thread switching.
 450  */
 451 struct task_struct *__switch_to(struct task_struct *prev,
 452                                 struct task_struct *next)
 453 {
 454         struct task_struct *last;
 455
 456         fpsimd_thread_switch(next);
 457         tls_thread_switch(next);
 458         hw_breakpoint_thread_switch(next);
 459         contextidr_thread_switch(next);
 460
 461         /*
 462          * Complete any pending TLB or cache maintenance on this CPU in case
 463          * the thread migrates to a different CPU.
 464          */
 465         dsb();
 466
 467         /* the actual thread switch */
 468         last = cpu_switch_to(prev, next);
 469
 470         return last;
 471 }
 472
 473 unsigned long get_wchan(struct task_struct *p)
 474 {
 475         struct stackframe frame;
 476         int count = 0;
 477         if (!p || p == current || p->state == TASK_RUNNING)
 478                 return 0;
 479
 480         frame.fp = thread_saved_fp(p);
 481         frame.sp = thread_saved_sp(p);
 482         frame.pc = thread_saved_pc(p);
 483         do {
 484                 int ret = unwind_frame(&frame);
 485                 if (ret < 0)
 486                         return 0;
 487                 if (!in_sched_functions(frame.pc))
 488                         return frame.pc;
 489         } while (count ++ < 16);
 490         return 0;
 491 }
 492
 493 unsigned long arch_align_stack(unsigned long sp)
 494 {
 495         if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
 496                 sp -= get_random_int() & ~PAGE_MASK;
 497         return sp & ~0xf;
 498 }
 499
 500 static unsigned long randomize_base(unsigned long base)
 501 {
 502         unsigned long range_end = base + (STACK_RND_MASK << PAGE_SHIFT) + 1;
 503         return randomize_range(base, range_end, 0) ? : base;
 504 }
 505
 506 unsigned long arch_randomize_brk(struct mm_struct *mm)
 507 {
 508         return randomize_base(mm->brk);
 509 }
 510
 511 unsigned long randomize_et_dyn(unsigned long base)
 512 {
 513         return randomize_base(base);
 514 }