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