arch/sh64/kernel/process.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * arch/sh64/kernel/process.c
   7  *
   8  * Copyright (C) 2000, 2001  Paolo Alberelli
   9  * Copyright (C) 2003  Paul Mundt
  10  * Copyright (C) 2003, 2004 Richard Curnow
  11  *
  12  * Started from SH3/4 version:
  13  *   Copyright (C) 1999, 2000  Niibe Yutaka & Kaz Kojima
  14  *
  15  *   In turn started from i386 version:
  16  *     Copyright (C) 1995  Linus Torvalds
  17  *
  18  */
  19
  20 /*
  21  * This file handles the architecture-dependent parts of process handling..
  22  */
  23
  24 /* Temporary flags/tests. All to be removed/undefined. BEGIN */
  25 #define IDLE_TRACE
  26 #define VM_SHOW_TABLES
  27 #define VM_TEST_FAULT
  28 #define VM_TEST_RTLBMISS
  29 #define VM_TEST_WTLBMISS
  30
  31 #undef VM_SHOW_TABLES
  32 #undef IDLE_TRACE
  33 /* Temporary flags/tests. All to be removed/undefined. END */
  34
  35 #define __KERNEL_SYSCALLS__
  36 #include <stdarg.h>
  37
  38 #include <linux/config.h>
  39 #include <linux/kernel.h>
  40 #include <linux/rwsem.h>
  41 #include <linux/mm.h>
  42 #include <linux/smp.h>
  43 #include <linux/smp_lock.h>
  44 #include <linux/ptrace.h>
  45 #include <linux/slab.h>
  46 #include <linux/vmalloc.h>
  47 #include <linux/user.h>
  48 #include <linux/a.out.h>
  49 #include <linux/interrupt.h>
  50 #include <linux/unistd.h>
  51 #include <linux/delay.h>
  52 #include <linux/reboot.h>
  53 #include <linux/init.h>
  54
  55 #include <asm/uaccess.h>
  56 #include <asm/pgtable.h>
  57 #include <asm/system.h>
  58 #include <asm/io.h>
  59 #include <asm/processor.h>              /* includes also <asm/registers.h> */
  60 #include <asm/mmu_context.h>
  61 #include <asm/elf.h>
  62 #include <asm/page.h>
  63
  64 #include <linux/irq.h>
  65
  66 struct task_struct *last_task_used_math = NULL;
  67
  68 #ifdef IDLE_TRACE
  69 #ifdef VM_SHOW_TABLES
  70 /* For testing */
  71 static void print_PTE(long base)
  72 {
  73         int i, skip=0;
  74         long long x, y, *p = (long long *) base;
  75
  76         for (i=0; i< 512; i++, p++){
  77                 if (*p == 0) {
  78                         if (!skip) {
  79                                 skip++;
  80                                 printk("(0s) ");
  81                         }
  82                 } else {
  83                         skip=0;
  84                         x = (*p) >> 32;
  85                         y = (*p) & 0xffffffff;
  86                         printk("%08Lx%08Lx ", x, y);
  87                         if (!((i+1)&0x3)) printk("\n");
  88                 }
  89         }
  90 }
  91
  92 /* For testing */
  93 static void print_DIR(long base)
  94 {
  95         int i, skip=0;
  96         long *p = (long *) base;
  97
  98         for (i=0; i< 512; i++, p++){
  99                 if (*p == 0) {
 100                         if (!skip) {
 101                                 skip++;
 102                                 printk("(0s) ");
 103                         }
 104                 } else {
 105                         skip=0;
 106                         printk("%08lx ", *p);
 107                         if (!((i+1)&0x7)) printk("\n");
 108                 }
 109         }
 110 }
 111
 112 /* For testing */
 113 static void print_vmalloc_first_tables(void)
 114 {
 115
 116 #define PRESENT 0x800   /* Bit 11 */
 117
 118         /*
 119          * Do it really dirty by looking at raw addresses,
 120          * raw offsets, no types. If we used pgtable/pgalloc
 121          * macros/definitions we could hide potential bugs.
 122          *
 123          * Note that pointers are 32-bit for CDC.
 124          */
 125         long pgdt, pmdt, ptet;
 126
 127         pgdt = (long) &swapper_pg_dir;
 128         printk("-->PGD (0x%08lx):\n", pgdt);
 129         print_DIR(pgdt);
 130         printk("\n");
 131
 132         /* VMALLOC pool is mapped at 0xc0000000, second (pointer) entry in PGD */
 133         pgdt += 4;
 134         pmdt = (long) (* (long *) pgdt);
 135         if (!(pmdt & PRESENT)) {
 136                 printk("No PMD\n");
 137                 return;
 138         } else pmdt &= 0xfffff000;
 139
 140         printk("-->PMD (0x%08lx):\n", pmdt);
 141         print_DIR(pmdt);
 142         printk("\n");
 143
 144         /* Get the pmdt displacement for 0xc0000000 */
 145         pmdt += 2048;
 146
 147         /* just look at first two address ranges ... */
 148         /* ... 0xc0000000 ... */
 149         ptet = (long) (* (long *) pmdt);
 150         if (!(ptet & PRESENT)) {
 151                 printk("No PTE0\n");
 152                 return;
 153         } else ptet &= 0xfffff000;
 154
 155         printk("-->PTE0 (0x%08lx):\n", ptet);
 156         print_PTE(ptet);
 157         printk("\n");
 158
 159         /* ... 0xc0001000 ... */
 160         ptet += 4;
 161         if (!(ptet & PRESENT)) {
 162                 printk("No PTE1\n");
 163                 return;
 164         } else ptet &= 0xfffff000;
 165         printk("-->PTE1 (0x%08lx):\n", ptet);
 166         print_PTE(ptet);
 167         printk("\n");
 168 }
 169 #else
 170 #define print_vmalloc_first_tables()
 171 #endif  /* VM_SHOW_TABLES */
 172
 173 static void test_VM(void)
 174 {
 175         void *a, *b, *c;
 176
 177 #ifdef VM_SHOW_TABLES
 178         printk("Initial PGD/PMD/PTE\n");
 179 #endif
 180         print_vmalloc_first_tables();
 181
 182         printk("Allocating 2 bytes\n");
 183         a = vmalloc(2);
 184         print_vmalloc_first_tables();
 185
 186         printk("Allocating 4100 bytes\n");
 187         b = vmalloc(4100);
 188         print_vmalloc_first_tables();
 189
 190         printk("Allocating 20234 bytes\n");
 191         c = vmalloc(20234);
 192         print_vmalloc_first_tables();
 193
 194 #ifdef VM_TEST_FAULT
 195         /* Here you may want to fault ! */
 196
 197 #ifdef VM_TEST_RTLBMISS
 198         printk("Ready to fault upon read.\n");
 199         if (* (char *) a) {
 200                 printk("RTLBMISSed on area a !\n");
 201         }
 202         printk("RTLBMISSed on area a !\n");
 203 #endif
 204
 205 #ifdef VM_TEST_WTLBMISS
 206         printk("Ready to fault upon write.\n");
 207         *((char *) b) = 'L';
 208         printk("WTLBMISSed on area b !\n");
 209 #endif
 210
 211 #endif  /* VM_TEST_FAULT */
 212
 213         printk("Deallocating the 4100 byte chunk\n");
 214         vfree(b);
 215         print_vmalloc_first_tables();
 216
 217         printk("Deallocating the 2 byte chunk\n");
 218         vfree(a);
 219         print_vmalloc_first_tables();
 220
 221         printk("Deallocating the last chunk\n");
 222         vfree(c);
 223         print_vmalloc_first_tables();
 224 }
 225
 226 extern unsigned long volatile jiffies;
 227 int once = 0;
 228 unsigned long old_jiffies;
 229 int pid = -1, pgid = -1;
 230
 231 void idle_trace(void)
 232 {
 233
 234         _syscall0(int, getpid)
 235         _syscall1(int, getpgid, int, pid)
 236
 237         if (!once) {
 238                 /* VM allocation/deallocation simple test */
 239                 test_VM();
 240                 pid = getpid();
 241
 242                 printk("Got all through to Idle !!\n");
 243                 printk("I'm now going to loop forever ...\n");
 244                 printk("Any ! below is a timer tick.\n");
 245                 printk("Any . below is a getpgid system call from pid = %d.\n", pid);
 246
 247
 248                 old_jiffies = jiffies;
 249                 once++;
 250         }
 251
 252         if (old_jiffies != jiffies) {
 253                 old_jiffies = jiffies - old_jiffies;
 254                 switch (old_jiffies) {
 255                 case 1:
 256                         printk("!");
 257                         break;
 258                 case 2:
 259                         printk("!!");
 260                         break;
 261                 case 3:
 262                         printk("!!!");
 263                         break;
 264                 case 4:
 265                         printk("!!!!");
 266                         break;
 267                 default:
 268                         printk("(%d!)", (int) old_jiffies);
 269                 }
 270                 old_jiffies = jiffies;
 271         }
 272         pgid = getpgid(pid);
 273         printk(".");
 274 }
 275 #else
 276 #define idle_trace()    do { } while (0)
 277 #endif  /* IDLE_TRACE */
 278
 279 static int hlt_counter = 1;
 280
 281 #define HARD_IDLE_TIMEOUT (HZ / 3)
 282
 283 void disable_hlt(void)
 284 {
 285         hlt_counter++;
 286 }
 287
 288 void enable_hlt(void)
 289 {
 290         hlt_counter--;
 291 }
 292
 293 static int __init nohlt_setup(char *__unused)
 294 {
 295         hlt_counter = 1;
 296         return 1;
 297 }
 298
 299 static int __init hlt_setup(char *__unused)
 300 {
 301         hlt_counter = 0;
 302         return 1;
 303 }
 304
 305 __setup("nohlt", nohlt_setup);
 306 __setup("hlt", hlt_setup);
 307
 308 static inline void hlt(void)
 309 {
 310         if (hlt_counter)
 311                 return;
 312
 313         __asm__ __volatile__ ("sleep" : : : "memory");
 314 }
 315
 316 /*
 317  * The idle loop on a uniprocessor SH..
 318  */
 319 void default_idle(void)
 320 {
 321         /* endless idle loop with no priority at all */
 322         while (1) {
 323                 if (hlt_counter) {
 324                         while (1)
 325                                 if (need_resched())
 326                                         break;
 327                 } else {
 328                         local_irq_disable();
 329                         while (!need_resched()) {
 330                                 local_irq_enable();
 331                                 idle_trace();
 332                                 hlt();
 333                                 local_irq_disable();
 334                         }
 335                         local_irq_enable();
 336                 }
 337                 schedule();
 338         }
 339 }
 340
 341 void cpu_idle(void)
 342 {
 343         default_idle();
 344 }
 345
 346 void machine_restart(char * __unused)
 347 {
 348         extern void phys_stext(void);
 349
 350         phys_stext();
 351 }
 352
 353 void machine_halt(void)
 354 {
 355         for (;;);
 356 }
 357
 358 void machine_power_off(void)
 359 {
 360         extern void enter_deep_standby(void);
 361
 362         enter_deep_standby();
 363 }
 364
 365 void show_regs(struct pt_regs * regs)
 366 {
 367         unsigned long long ah, al, bh, bl, ch, cl;
 368
 369         printk("\n");
 370
 371         ah = (regs->pc) >> 32;
 372         al = (regs->pc) & 0xffffffff;
 373         bh = (regs->regs[18]) >> 32;
 374         bl = (regs->regs[18]) & 0xffffffff;
 375         ch = (regs->regs[15]) >> 32;
 376         cl = (regs->regs[15]) & 0xffffffff;
 377         printk("PC  : %08Lx%08Lx LINK: %08Lx%08Lx SP  : %08Lx%08Lx\n",
 378                ah, al, bh, bl, ch, cl);
 379
 380         ah = (regs->sr) >> 32;
 381         al = (regs->sr) & 0xffffffff;
 382         asm volatile ("getcon   " __TEA ", %0" : "=r" (bh));
 383         asm volatile ("getcon   " __TEA ", %0" : "=r" (bl));
 384         bh = (bh) >> 32;
 385         bl = (bl) & 0xffffffff;
 386         asm volatile ("getcon   " __KCR0 ", %0" : "=r" (ch));
 387         asm volatile ("getcon   " __KCR0 ", %0" : "=r" (cl));
 388         ch = (ch) >> 32;
 389         cl = (cl) & 0xffffffff;
 390         printk("SR  : %08Lx%08Lx TEA : %08Lx%08Lx KCR0: %08Lx%08Lx\n",
 391                ah, al, bh, bl, ch, cl);
 392
 393         ah = (regs->regs[0]) >> 32;
 394         al = (regs->regs[0]) & 0xffffffff;
 395         bh = (regs->regs[1]) >> 32;
 396         bl = (regs->regs[1]) & 0xffffffff;
 397         ch = (regs->regs[2]) >> 32;
 398         cl = (regs->regs[2]) & 0xffffffff;
 399         printk("R0  : %08Lx%08Lx R1  : %08Lx%08Lx R2  : %08Lx%08Lx\n",
 400                ah, al, bh, bl, ch, cl);
 401
 402         ah = (regs->regs[3]) >> 32;
 403         al = (regs->regs[3]) & 0xffffffff;
 404         bh = (regs->regs[4]) >> 32;
 405         bl = (regs->regs[4]) & 0xffffffff;
 406         ch = (regs->regs[5]) >> 32;
 407         cl = (regs->regs[5]) & 0xffffffff;
 408         printk("R3  : %08Lx%08Lx R4  : %08Lx%08Lx R5  : %08Lx%08Lx\n",
 409                ah, al, bh, bl, ch, cl);
 410
 411         ah = (regs->regs[6]) >> 32;
 412         al = (regs->regs[6]) & 0xffffffff;
 413         bh = (regs->regs[7]) >> 32;
 414         bl = (regs->regs[7]) & 0xffffffff;
 415         ch = (regs->regs[8]) >> 32;
 416         cl = (regs->regs[8]) & 0xffffffff;
 417         printk("R6  : %08Lx%08Lx R7  : %08Lx%08Lx R8  : %08Lx%08Lx\n",
 418                ah, al, bh, bl, ch, cl);
 419
 420         ah = (regs->regs[9]) >> 32;
 421         al = (regs->regs[9]) & 0xffffffff;
 422         bh = (regs->regs[10]) >> 32;
 423         bl = (regs->regs[10]) & 0xffffffff;
 424         ch = (regs->regs[11]) >> 32;
 425         cl = (regs->regs[11]) & 0xffffffff;
 426         printk("R9  : %08Lx%08Lx R10 : %08Lx%08Lx R11 : %08Lx%08Lx\n",
 427                ah, al, bh, bl, ch, cl);
 428
 429         ah = (regs->regs[12]) >> 32;
 430         al = (regs->regs[12]) & 0xffffffff;
 431         bh = (regs->regs[13]) >> 32;
 432         bl = (regs->regs[13]) & 0xffffffff;
 433         ch = (regs->regs[14]) >> 32;
 434         cl = (regs->regs[14]) & 0xffffffff;
 435         printk("R12 : %08Lx%08Lx R13 : %08Lx%08Lx R14 : %08Lx%08Lx\n",
 436                ah, al, bh, bl, ch, cl);
 437
 438         ah = (regs->regs[16]) >> 32;
 439         al = (regs->regs[16]) & 0xffffffff;
 440         bh = (regs->regs[17]) >> 32;
 441         bl = (regs->regs[17]) & 0xffffffff;
 442         ch = (regs->regs[19]) >> 32;
 443         cl = (regs->regs[19]) & 0xffffffff;
 444         printk("R16 : %08Lx%08Lx R17 : %08Lx%08Lx R19 : %08Lx%08Lx\n",
 445                ah, al, bh, bl, ch, cl);
 446
 447         ah = (regs->regs[20]) >> 32;
 448         al = (regs->regs[20]) & 0xffffffff;
 449         bh = (regs->regs[21]) >> 32;
 450         bl = (regs->regs[21]) & 0xffffffff;
 451         ch = (regs->regs[22]) >> 32;
 452         cl = (regs->regs[22]) & 0xffffffff;
 453         printk("R20 : %08Lx%08Lx R21 : %08Lx%08Lx R22 : %08Lx%08Lx\n",
 454                ah, al, bh, bl, ch, cl);
 455
 456         ah = (regs->regs[23]) >> 32;
 457         al = (regs->regs[23]) & 0xffffffff;
 458         bh = (regs->regs[24]) >> 32;
 459         bl = (regs->regs[24]) & 0xffffffff;
 460         ch = (regs->regs[25]) >> 32;
 461         cl = (regs->regs[25]) & 0xffffffff;
 462         printk("R23 : %08Lx%08Lx R24 : %08Lx%08Lx R25 : %08Lx%08Lx\n",
 463                ah, al, bh, bl, ch, cl);
 464
 465         ah = (regs->regs[26]) >> 32;
 466         al = (regs->regs[26]) & 0xffffffff;
 467         bh = (regs->regs[27]) >> 32;
 468         bl = (regs->regs[27]) & 0xffffffff;
 469         ch = (regs->regs[28]) >> 32;
 470         cl = (regs->regs[28]) & 0xffffffff;
 471         printk("R26 : %08Lx%08Lx R27 : %08Lx%08Lx R28 : %08Lx%08Lx\n",
 472                ah, al, bh, bl, ch, cl);
 473
 474         ah = (regs->regs[29]) >> 32;
 475         al = (regs->regs[29]) & 0xffffffff;
 476         bh = (regs->regs[30]) >> 32;
 477         bl = (regs->regs[30]) & 0xffffffff;
 478         ch = (regs->regs[31]) >> 32;
 479         cl = (regs->regs[31]) & 0xffffffff;
 480         printk("R29 : %08Lx%08Lx R30 : %08Lx%08Lx R31 : %08Lx%08Lx\n",
 481                ah, al, bh, bl, ch, cl);
 482
 483         ah = (regs->regs[32]) >> 32;
 484         al = (regs->regs[32]) & 0xffffffff;
 485         bh = (regs->regs[33]) >> 32;
 486         bl = (regs->regs[33]) & 0xffffffff;
 487         ch = (regs->regs[34]) >> 32;
 488         cl = (regs->regs[34]) & 0xffffffff;
 489         printk("R32 : %08Lx%08Lx R33 : %08Lx%08Lx R34 : %08Lx%08Lx\n",
 490                ah, al, bh, bl, ch, cl);
 491
 492         ah = (regs->regs[35]) >> 32;
 493         al = (regs->regs[35]) & 0xffffffff;
 494         bh = (regs->regs[36]) >> 32;
 495         bl = (regs->regs[36]) & 0xffffffff;
 496         ch = (regs->regs[37]) >> 32;
 497         cl = (regs->regs[37]) & 0xffffffff;
 498         printk("R35 : %08Lx%08Lx R36 : %08Lx%08Lx R37 : %08Lx%08Lx\n",
 499                ah, al, bh, bl, ch, cl);
 500
 501         ah = (regs->regs[38]) >> 32;
 502         al = (regs->regs[38]) & 0xffffffff;
 503         bh = (regs->regs[39]) >> 32;
 504         bl = (regs->regs[39]) & 0xffffffff;
 505         ch = (regs->regs[40]) >> 32;
 506         cl = (regs->regs[40]) & 0xffffffff;
 507         printk("R38 : %08Lx%08Lx R39 : %08Lx%08Lx R40 : %08Lx%08Lx\n",
 508                ah, al, bh, bl, ch, cl);
 509
 510         ah = (regs->regs[41]) >> 32;
 511         al = (regs->regs[41]) & 0xffffffff;
 512         bh = (regs->regs[42]) >> 32;
 513         bl = (regs->regs[42]) & 0xffffffff;
 514         ch = (regs->regs[43]) >> 32;
 515         cl = (regs->regs[43]) & 0xffffffff;
 516         printk("R41 : %08Lx%08Lx R42 : %08Lx%08Lx R43 : %08Lx%08Lx\n",
 517                ah, al, bh, bl, ch, cl);
 518
 519         ah = (regs->regs[44]) >> 32;
 520         al = (regs->regs[44]) & 0xffffffff;
 521         bh = (regs->regs[45]) >> 32;
 522         bl = (regs->regs[45]) & 0xffffffff;
 523         ch = (regs->regs[46]) >> 32;
 524         cl = (regs->regs[46]) & 0xffffffff;
 525         printk("R44 : %08Lx%08Lx R45 : %08Lx%08Lx R46 : %08Lx%08Lx\n",
 526                ah, al, bh, bl, ch, cl);
 527
 528         ah = (regs->regs[47]) >> 32;
 529         al = (regs->regs[47]) & 0xffffffff;
 530         bh = (regs->regs[48]) >> 32;
 531         bl = (regs->regs[48]) & 0xffffffff;
 532         ch = (regs->regs[49]) >> 32;
 533         cl = (regs->regs[49]) & 0xffffffff;
 534         printk("R47 : %08Lx%08Lx R48 : %08Lx%08Lx R49 : %08Lx%08Lx\n",
 535                ah, al, bh, bl, ch, cl);
 536
 537         ah = (regs->regs[50]) >> 32;
 538         al = (regs->regs[50]) & 0xffffffff;
 539         bh = (regs->regs[51]) >> 32;
 540         bl = (regs->regs[51]) & 0xffffffff;
 541         ch = (regs->regs[52]) >> 32;
 542         cl = (regs->regs[52]) & 0xffffffff;
 543         printk("R50 : %08Lx%08Lx R51 : %08Lx%08Lx R52 : %08Lx%08Lx\n",
 544                ah, al, bh, bl, ch, cl);
 545
 546         ah = (regs->regs[53]) >> 32;
 547         al = (regs->regs[53]) & 0xffffffff;
 548         bh = (regs->regs[54]) >> 32;
 549         bl = (regs->regs[54]) & 0xffffffff;
 550         ch = (regs->regs[55]) >> 32;
 551         cl = (regs->regs[55]) & 0xffffffff;
 552         printk("R53 : %08Lx%08Lx R54 : %08Lx%08Lx R55 : %08Lx%08Lx\n",
 553                ah, al, bh, bl, ch, cl);
 554
 555         ah = (regs->regs[56]) >> 32;
 556         al = (regs->regs[56]) & 0xffffffff;
 557         bh = (regs->regs[57]) >> 32;
 558         bl = (regs->regs[57]) & 0xffffffff;
 559         ch = (regs->regs[58]) >> 32;
 560         cl = (regs->regs[58]) & 0xffffffff;
 561         printk("R56 : %08Lx%08Lx R57 : %08Lx%08Lx R58 : %08Lx%08Lx\n",
 562                ah, al, bh, bl, ch, cl);
 563
 564         ah = (regs->regs[59]) >> 32;
 565         al = (regs->regs[59]) & 0xffffffff;
 566         bh = (regs->regs[60]) >> 32;
 567         bl = (regs->regs[60]) & 0xffffffff;
 568         ch = (regs->regs[61]) >> 32;
 569         cl = (regs->regs[61]) & 0xffffffff;
 570         printk("R59 : %08Lx%08Lx R60 : %08Lx%08Lx R61 : %08Lx%08Lx\n",
 571                ah, al, bh, bl, ch, cl);
 572
 573         ah = (regs->regs[62]) >> 32;
 574         al = (regs->regs[62]) & 0xffffffff;
 575         bh = (regs->tregs[0]) >> 32;
 576         bl = (regs->tregs[0]) & 0xffffffff;
 577         ch = (regs->tregs[1]) >> 32;
 578         cl = (regs->tregs[1]) & 0xffffffff;
 579         printk("R62 : %08Lx%08Lx T0  : %08Lx%08Lx T1  : %08Lx%08Lx\n",
 580                ah, al, bh, bl, ch, cl);
 581
 582         ah = (regs->tregs[2]) >> 32;
 583         al = (regs->tregs[2]) & 0xffffffff;
 584         bh = (regs->tregs[3]) >> 32;
 585         bl = (regs->tregs[3]) & 0xffffffff;
 586         ch = (regs->tregs[4]) >> 32;
 587         cl = (regs->tregs[4]) & 0xffffffff;
 588         printk("T2  : %08Lx%08Lx T3  : %08Lx%08Lx T4  : %08Lx%08Lx\n",
 589                ah, al, bh, bl, ch, cl);
 590
 591         ah = (regs->tregs[5]) >> 32;
 592         al = (regs->tregs[5]) & 0xffffffff;
 593         bh = (regs->tregs[6]) >> 32;
 594         bl = (regs->tregs[6]) & 0xffffffff;
 595         ch = (regs->tregs[7]) >> 32;
 596         cl = (regs->tregs[7]) & 0xffffffff;
 597         printk("T5  : %08Lx%08Lx T6  : %08Lx%08Lx T7  : %08Lx%08Lx\n",
 598                ah, al, bh, bl, ch, cl);
 599
 600         /*
 601          * If we're in kernel mode, dump the stack too..
 602          */
 603         if (!user_mode(regs)) {
 604                 void show_stack(struct task_struct *tsk, unsigned long *sp);
 605                 unsigned long sp = regs->regs[15] & 0xffffffff;
 606                 struct task_struct *tsk = get_current();
 607
 608                 tsk->thread.kregs = regs;
 609
 610                 show_stack(tsk, (unsigned long *)sp);
 611         }
 612 }
 613
 614 struct task_struct * alloc_task_struct(void)
 615 {
 616         /* Get task descriptor pages */
 617         return (struct task_struct *)
 618                 __get_free_pages(GFP_KERNEL, get_order(THREAD_SIZE));
 619 }
 620
 621 void free_task_struct(struct task_struct *p)
 622 {
 623         free_pages((unsigned long) p, get_order(THREAD_SIZE));
 624 }
 625
 626 /*
 627  * Create a kernel thread
 628  */
 629
 630 /*
 631  * This is the mechanism for creating a new kernel thread.
 632  *
 633  * NOTE! Only a kernel-only process(ie the swapper or direct descendants
 634  * who haven't done an "execve()") should use this: it will work within
 635  * a system call from a "real" process, but the process memory space will
 636  * not be free'd until both the parent and the child have exited.
 637  */
 638 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 639 {
 640         /* A bit less processor dependent than older sh ... */
 641         unsigned int reply;
 642
 643 static __inline__ _syscall2(int,clone,unsigned long,flags,unsigned long,newsp)
 644 static __inline__ _syscall1(int,exit,int,ret)
 645
 646         reply = clone(flags | CLONE_VM, 0);
 647         if (!reply) {
 648                 /* Child */
 649                 reply = exit(fn(arg));
 650         }
 651
 652         return reply;
 653 }
 654
 655 /*
 656  * Free current thread data structures etc..
 657  */
 658 void exit_thread(void)
 659 {
 660         /* See arch/sparc/kernel/process.c for the precedent for doing this -- RPC.
 661
 662            The SH-5 FPU save/restore approach relies on last_task_used_math
 663            pointing to a live task_struct.  When another task tries to use the
 664            FPU for the 1st time, the FPUDIS trap handling (see
 665            arch/sh64/kernel/fpu.c) will save the existing FPU state to the
 666            FP regs field within last_task_used_math before re-loading the new
 667            task's FPU state (or initialising it if the FPU has been used
 668            before).  So if last_task_used_math is stale, and its page has already been
 669            re-allocated for another use, the consequences are rather grim. Unless we
 670            null it here, there is no other path through which it would get safely
 671            nulled. */
 672
 673 #ifdef CONFIG_SH_FPU
 674         if (last_task_used_math == current) {
 675                 last_task_used_math = NULL;
 676         }
 677 #endif
 678 }
 679
 680 void flush_thread(void)
 681 {
 682
 683         /* Called by fs/exec.c (flush_old_exec) to remove traces of a
 684          * previously running executable. */
 685 #ifdef CONFIG_SH_FPU
 686         if (last_task_used_math == current) {
 687                 last_task_used_math = NULL;
 688         }
 689         /* Force FPU state to be reinitialised after exec */
 690         clear_used_math();
 691 #endif
 692
 693         /* if we are a kernel thread, about to change to user thread,
 694          * update kreg
 695          */
 696         if(current->thread.kregs==&fake_swapper_regs) {
 697           current->thread.kregs =
 698              ((struct pt_regs *)(THREAD_SIZE + (unsigned long) current) - 1);
 699           current->thread.uregs = current->thread.kregs;
 700         }
 701 }
 702
 703 void release_thread(struct task_struct *dead_task)
 704 {
 705         /* do nothing */
 706 }
 707
 708 /* Fill in the fpu structure for a core dump.. */
 709 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
 710 {
 711 #ifdef CONFIG_SH_FPU
 712         int fpvalid;
 713         struct task_struct *tsk = current;
 714
 715         fpvalid = !!tsk_used_math(tsk);
 716         if (fpvalid) {
 717                 if (current == last_task_used_math) {
 718                         grab_fpu();
 719                         fpsave(&tsk->thread.fpu.hard);
 720                         release_fpu();
 721                         last_task_used_math = 0;
 722                         regs->sr |= SR_FD;
 723                 }
 724
 725                 memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
 726         }
 727
 728         return fpvalid;
 729 #else
 730         return 0; /* Task didn't use the fpu at all. */
 731 #endif
 732 }
 733
 734 asmlinkage void ret_from_fork(void);
 735
 736 int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
 737                 unsigned long unused,
 738                 struct task_struct *p, struct pt_regs *regs)
 739 {
 740         struct pt_regs *childregs;
 741         unsigned long long se;                  /* Sign extension */
 742
 743 #ifdef CONFIG_SH_FPU
 744         if(last_task_used_math == current) {
 745                 grab_fpu();
 746                 fpsave(&current->thread.fpu.hard);
 747                 release_fpu();
 748                 last_task_used_math = NULL;
 749                 regs->sr |= SR_FD;
 750         }
 751 #endif
 752         /* Copy from sh version */
 753         childregs = ((struct pt_regs *)(THREAD_SIZE + (unsigned long) p->thread_info )) - 1;
 754
 755         *childregs = *regs;
 756
 757         if (user_mode(regs)) {
 758                 childregs->regs[15] = usp;
 759                 p->thread.uregs = childregs;
 760         } else {
 761                 childregs->regs[15] = (unsigned long)p->thread_info + THREAD_SIZE;
 762         }
 763
 764         childregs->regs[9] = 0; /* Set return value for child */
 765         childregs->sr |= SR_FD; /* Invalidate FPU flag */
 766
 767         p->thread.sp = (unsigned long) childregs;
 768         p->thread.pc = (unsigned long) ret_from_fork;
 769
 770         /*
 771          * Sign extend the edited stack.
 772          * Note that thread.pc and thread.pc will stay
 773          * 32-bit wide and context switch must take care
 774          * of NEFF sign extension.
 775          */
 776
 777         se = childregs->regs[15];
 778         se = (se & NEFF_SIGN) ? (se | NEFF_MASK) : se;
 779         childregs->regs[15] = se;
 780
 781         return 0;
 782 }
 783
 784 /*
 785  * fill in the user structure for a core dump..
 786  */
 787 void dump_thread(struct pt_regs * regs, struct user * dump)
 788 {
 789         dump->magic = CMAGIC;
 790         dump->start_code = current->mm->start_code;
 791         dump->start_data  = current->mm->start_data;
 792         dump->start_stack = regs->regs[15] & ~(PAGE_SIZE - 1);
 793         dump->u_tsize = (current->mm->end_code - dump->start_code) >> PAGE_SHIFT;
 794         dump->u_dsize = (current->mm->brk + (PAGE_SIZE-1) - dump->start_data) >> PAGE_SHIFT;
 795         dump->u_ssize = (current->mm->start_stack - dump->start_stack +
 796                          PAGE_SIZE - 1) >> PAGE_SHIFT;
 797         /* Debug registers will come here. */
 798
 799         dump->regs = *regs;
 800
 801         dump->u_fpvalid = dump_fpu(regs, &dump->fpu);
 802 }
 803
 804 asmlinkage int sys_fork(unsigned long r2, unsigned long r3,
 805                         unsigned long r4, unsigned long r5,
 806                         unsigned long r6, unsigned long r7,
 807                         struct pt_regs *pregs)
 808 {
 809         return do_fork(SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
 810 }
 811
 812 asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
 813                          unsigned long r4, unsigned long r5,
 814                          unsigned long r6, unsigned long r7,
 815                          struct pt_regs *pregs)
 816 {
 817         if (!newsp)
 818                 newsp = pregs->regs[15];
 819         return do_fork(clone_flags, newsp, pregs, 0, 0, 0);
 820 }
 821
 822 /*
 823  * This is trivial, and on the face of it looks like it
 824  * could equally well be done in user mode.
 825  *
 826  * Not so, for quite unobvious reasons - register pressure.
 827  * In user mode vfork() cannot have a stack frame, and if
 828  * done by calling the "clone()" system call directly, you
 829  * do not have enough call-clobbered registers to hold all
 830  * the information you need.
 831  */
 832 asmlinkage int sys_vfork(unsigned long r2, unsigned long r3,
 833                          unsigned long r4, unsigned long r5,
 834                          unsigned long r6, unsigned long r7,
 835                          struct pt_regs *pregs)
 836 {
 837         return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
 838 }
 839
 840 /*
 841  * sys_execve() executes a new program.
 842  */
 843 asmlinkage int sys_execve(char *ufilename, char **uargv,
 844                           char **uenvp, unsigned long r5,
 845                           unsigned long r6, unsigned long r7,
 846                           struct pt_regs *pregs)
 847 {
 848         int error;
 849         char *filename;
 850
 851         lock_kernel();
 852         filename = getname((char __user *)ufilename);
 853         error = PTR_ERR(filename);
 854         if (IS_ERR(filename))
 855                 goto out;
 856
 857         error = do_execve(filename,
 858                           (char __user * __user *)uargv,
 859                           (char __user * __user *)uenvp,
 860                           pregs);
 861         if (error == 0) {
 862                 task_lock(current);
 863                 current->ptrace &= ~PT_DTRACE;
 864                 task_unlock(current);
 865         }
 866         putname(filename);
 867 out:
 868         unlock_kernel();
 869         return error;
 870 }
 871
 872 /*
 873  * These bracket the sleeping functions..
 874  */
 875 extern void interruptible_sleep_on(wait_queue_head_t *q);
 876
 877 #define mid_sched       ((unsigned long) interruptible_sleep_on)
 878
 879 static int in_sh64_switch_to(unsigned long pc)
 880 {
 881         extern char __sh64_switch_to_end;
 882         /* For a sleeping task, the PC is somewhere in the middle of the function,
 883            so we don't have to worry about masking the LSB off */
 884         return (pc >= (unsigned long) sh64_switch_to) &&
 885                (pc < (unsigned long) &__sh64_switch_to_end);
 886 }
 887
 888 unsigned long get_wchan(struct task_struct *p)
 889 {
 890         unsigned long schedule_fp;
 891         unsigned long sh64_switch_to_fp;
 892         unsigned long schedule_caller_pc;
 893         unsigned long pc;
 894
 895         if (!p || p == current || p->state == TASK_RUNNING)
 896                 return 0;
 897
 898         /*
 899          * The same comment as on the Alpha applies here, too ...
 900          */
 901         pc = thread_saved_pc(p);
 902
 903 #ifdef CONFIG_FRAME_POINTER
 904         if (in_sh64_switch_to(pc)) {
 905                 sh64_switch_to_fp = (long) p->thread.sp;
 906                 /* r14 is saved at offset 4 in the sh64_switch_to frame */
 907                 schedule_fp = *(unsigned long *) (long)(sh64_switch_to_fp + 4);
 908
 909                 /* and the caller of 'schedule' is (currently!) saved at offset 24
 910                    in the frame of schedule (from disasm) */
 911                 schedule_caller_pc = *(unsigned long *) (long)(schedule_fp + 24);
 912                 return schedule_caller_pc;
 913         }
 914 #endif
 915         return pc;
 916 }
 917
 918 /* Provide a /proc/asids file that lists out the
 919    ASIDs currently associated with the processes.  (If the DM.PC register is
 920    examined through the debug link, this shows ASID + PC.  To make use of this,
 921    the PID->ASID relationship needs to be known.  This is primarily for
 922    debugging.)
 923    */
 924
 925 #if defined(CONFIG_SH64_PROC_ASIDS)
 926 #include <linux/init.h>
 927 #include <linux/proc_fs.h>
 928
 929 static int
 930 asids_proc_info(char *buf, char **start, off_t fpos, int length, int *eof, void *data)
 931 {
 932         int len=0;
 933         struct task_struct *p;
 934         read_lock(&tasklist_lock);
 935         for_each_process(p) {
 936                 int pid = p->pid;
 937                 struct mm_struct *mm;
 938                 if (!pid) continue;
 939                 mm = p->mm;
 940                 if (mm) {
 941                         unsigned long asid, context;
 942                         context = mm->context;
 943                         asid = (context & 0xff);
 944                         len += sprintf(buf+len, "%5d : %02lx\n", pid, asid);
 945                 } else {
 946                         len += sprintf(buf+len, "%5d : (none)\n", pid);
 947                 }
 948         }
 949         read_unlock(&tasklist_lock);
 950         *eof = 1;
 951         return len;
 952 }
 953
 954 static int __init register_proc_asids(void)
 955 {
 956   create_proc_read_entry("asids", 0, NULL, asids_proc_info, NULL);
 957   return 0;
 958 }
 959
 960 __initcall(register_proc_asids);
 961 #endif
 962