aboutsummaryrefslogtreecommitdiffstats
path: root/arch/m68k/kernel/sys_m68k.c
blob: 77896692eb0a69f34609cb4809e221fc84fb4bd3 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
/*
 * linux/arch/m68k/kernel/sys_m68k.c
 *
 * This file contains various random system calls that
 * have a non-standard calling sequence on the Linux/m68k
 * platform.
 */

#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/sem.h>
#include <linux/msg.h>
#include <linux/shm.h>
#include <linux/stat.h>
#include <linux/syscalls.h>
#include <linux/mman.h>
#include <linux/file.h>
#include <linux/ipc.h>

#include <asm/setup.h>
#include <asm/uaccess.h>
#include <asm/cachectl.h>
#include <asm/traps.h>
#include <asm/page.h>
#include <asm/unistd.h>
#include <linux/elf.h>
#include <asm/tlb.h>

asmlinkage int do_page_fault(struct pt_regs *regs, unsigned long address,
			     unsigned long error_code);

asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
	unsigned long prot, unsigned long flags,
	unsigned long fd, unsigned long pgoff)
{
	/*
	 * This is wrong for sun3 - there PAGE_SIZE is 8Kb,
	 * so we need to shift the argument down by 1; m68k mmap64(3)
	 * (in libc) expects the last argument of mmap2 in 4Kb units.
	 */
	return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);
}

/* Convert virtual (user) address VADDR to physical address PADDR */
#define virt_to_phys_040(vaddr)						\
({									\
  unsigned long _mmusr, _paddr;						\
									\
  __asm__ __volatile__ (".chip 68040\n\t"				\
			"ptestr (%1)\n\t"				\
			"movec %%mmusr,%0\n\t"				\
			".chip 68k"					\
			: "=r" (_mmusr)					\
			: "a" (vaddr));					\
  _paddr = (_mmusr & MMU_R_040) ? (_mmusr & PAGE_MASK) : 0;		\
  _paddr;								\
})

static inline int
cache_flush_040 (unsigned long addr, int scope, int cache, unsigned long len)
{
  unsigned long paddr, i;

  switch (scope)
    {
    case FLUSH_SCOPE_ALL:
      switch (cache)
	{
	case FLUSH_CACHE_DATA:
	  /* This nop is needed for some broken versions of the 68040.  */
	  __asm__ __volatile__ ("nop\n\t"
				".chip 68040\n\t"
				"cpusha %dc\n\t"
				".chip 68k");
	  break;
	case FLUSH_CACHE_INSN:
	  __asm__ __volatile__ ("nop\n\t"
				".chip 68040\n\t"
				"cpusha %ic\n\t"
				".chip 68k");
	  break;
	default:
	case FLUSH_CACHE_BOTH:
	  __asm__ __volatile__ ("nop\n\t"
				".chip 68040\n\t"
				"cpusha %bc\n\t"
				".chip 68k");
	  break;
	}
      break;

    case FLUSH_SCOPE_LINE:
      /* Find the physical address of the first mapped page in the
	 address range.  */
      if ((paddr = virt_to_phys_040(addr))) {
        paddr += addr & ~(PAGE_MASK | 15);
        len = (len + (addr & 15) + 15) >> 4;
      } else {
	unsigned long tmp = PAGE_SIZE - (addr & ~PAGE_MASK);

	if (len <= tmp)
	  return 0;
	addr += tmp;
	len -= tmp;
	tmp = PAGE_SIZE;
	for (;;)
	  {
	    if ((paddr = virt_to_phys_040(addr)))
	      break;
	    if (len <= tmp)
	      return 0;
	    addr += tmp;
	    len -= tmp;
	  }
	len = (len + 15) >> 4;
      }
      i = (PAGE_SIZE - (paddr & ~PAGE_MASK)) >> 4;
      while (len--)
	{
	  switch (cache)
	    {
	    case FLUSH_CACHE_DATA:
	      __asm__ __volatile__ ("nop\n\t"
				    ".chip 68040\n\t"
				    "cpushl %%dc,(%0)\n\t"
				    ".chip 68k"
				    : : "a" (paddr));
	      break;
	    case FLUSH_CACHE_INSN:
	      __asm__ __volatile__ ("nop\n\t"
				    ".chip 68040\n\t"
				    "cpushl %%ic,(%0)\n\t"
				    ".chip 68k"
				    : : "a" (paddr));
	      break;
	    default:
	    case FLUSH_CACHE_BOTH:
	      __asm__ __volatile__ ("nop\n\t"
				    ".chip 68040\n\t"
				    "cpushl %%bc,(%0)\n\t"
				    ".chip 68k"
				    : : "a" (paddr));
	      break;
	    }
	  if (!--i && len)
	    {
	      /*
	       * No need to page align here since it is done by
	       * virt_to_phys_040().
	       */
	      addr += PAGE_SIZE;
	      i = PAGE_SIZE / 16;
	      /* Recompute physical address when crossing a page
	         boundary. */
	      for (;;)
		{
		  if ((paddr = virt_to_phys_040(addr)))
		    break;
		  if (len <= i)
		    return 0;
		  len -= i;
		  addr += PAGE_SIZE;
		}
	    }
	  else
	    paddr += 16;
	}
      break;

    default:
    case FLUSH_SCOPE_PAGE:
      len += (addr & ~PAGE_MASK) + (PAGE_SIZE - 1);
      for (len >>= PAGE_SHIFT; len--; addr += PAGE_SIZE)
	{
	  if (!(paddr = virt_to_phys_040(addr)))
	    continue;
	  switch (cache)
	    {
	    case FLUSH_CACHE_DATA:
	      __asm__ __volatile__ ("nop\n\t"
				    ".chip 68040\n\t"
				    "cpushp %%dc,(%0)\n\t"
				    ".chip 68k"
				    : : "a" (paddr));
	      break;
	    case FLUSH_CACHE_INSN:
	      __asm__ __volatile__ ("nop\n\t"
				    ".chip 68040\n\t"
				    "cpushp %%ic,(%0)\n\t"
				    ".chip 68k"
				    : : "a" (paddr));
	      break;
	    default:
	    case FLUSH_CACHE_BOTH:
	      __asm__ __volatile__ ("nop\n\t"
				    ".chip 68040\n\t"
				    "cpushp %%bc,(%0)\n\t"
				    ".chip 68k"
				    : : "a" (paddr));
	      break;
	    }
	}
      break;
    }
  return 0;
}

#define virt_to_phys_060(vaddr)				\
({							\
  unsigned long paddr;					\
  __asm__ __volatile__ (".chip 68060\n\t"		\
			"plpar (%0)\n\t"		\
			".chip 68k"			\
			: "=a" (paddr)			\
			: "0" (vaddr));			\
  (paddr); /* XXX */					\
})

static inline int
cache_flush_060 (unsigned long addr, int scope, int cache, unsigned long len)
{
  unsigned long paddr, i;

  /*
   * 68060 manual says:
   *  cpush %dc : flush DC, remains valid (with our %cacr setup)
   *  cpush %ic : invalidate IC
   *  cpush %bc : flush DC + invalidate IC
   */
  switch (scope)
    {
    case FLUSH_SCOPE_ALL:
      switch (cache)
	{
	case FLUSH_CACHE_DATA:
	  __asm__ __volatile__ (".chip 68060\n\t"
				"cpusha %dc\n\t"
				".chip 68k");
	  break;
	case FLUSH_CACHE_INSN:
	  __asm__ __volatile__ (".chip 68060\n\t"
				"cpusha %ic\n\t"
				".chip 68k");
	  break;
	default:
	case FLUSH_CACHE_BOTH:
	  __asm__ __volatile__ (".chip 68060\n\t"
				"cpusha %bc\n\t"
				".chip 68k");
	  break;
	}
      break;

    case FLUSH_SCOPE_LINE:
      /* Find the physical address of the first mapped page in the
	 address range.  */
      len += addr & 15;
      addr &= -16;
      if (!(paddr = virt_to_phys_060(addr))) {
	unsigned long tmp = PAGE_SIZE - (addr & ~PAGE_MASK);

	if (len <= tmp)
	  return 0;
	addr += tmp;
	len -= tmp;
	tmp = PAGE_SIZE;
	for (;;)
	  {
	    if ((paddr = virt_to_phys_060(addr)))
	      break;
	    if (len <= tmp)
	      return 0;
	    addr += tmp;
	    len -= tmp;
	  }
      }
      len = (len + 15) >> 4;
      i = (PAGE_SIZE - (paddr & ~PAGE_MASK)) >> 4;
      while (len--)
	{
	  switch (cache)
	    {
	    case FLUSH_CACHE_DATA:
	      __asm__ __volatile__ (".chip 68060\n\t"
				    "cpushl %%dc,(%0)\n\t"
				    ".chip 68k"
				    : : "a" (paddr));
	      break;
	    case FLUSH_CACHE_INSN:
	      __asm__ __volatile__ (".chip 68060\n\t"
				    "cpushl %%ic,(%0)\n\t"
				    ".chip 68k"
				    : : "a" (paddr));
	      break;
	    default:
	    case FLUSH_CACHE_BOTH:
	      __asm__ __volatile__ (".chip 68060\n\t"
				    "cpushl %%bc,(%0)\n\t"
				    ".chip 68k"
				    : : "a" (paddr));
	      break;
	    }
	  if (!--i && len)
	    {

	      /*
	       * We just want to jump to the first cache line
	       * in the next page.
	       */
	      addr += PAGE_SIZE;
	      addr &= PAGE_MASK;

	      i = PAGE_SIZE / 16;
	      /* Recompute physical address when crossing a page
	         boundary. */
	      for (;;)
	        {
	          if ((paddr = virt_to_phys_060(addr)))
	            break;
	          if (len <= i)
	            return 0;
	          len -= i;
	          addr += PAGE_SIZE;
	        }
	    }
	  else
	    paddr += 16;
	}
      break;

    default:
    case FLUSH_SCOPE_PAGE:
      len += (addr & ~PAGE_MASK) + (PAGE_SIZE - 1);
      addr &= PAGE_MASK;	/* Workaround for bug in some
				   revisions of the 68060 */
      for (len >>= PAGE_SHIFT; len--; addr += PAGE_SIZE)
	{
	  if (!(paddr = virt_to_phys_060(addr)))
	    continue;
	  switch (cache)
	    {
	    case FLUSH_CACHE_DATA:
	      __asm__ __volatile__ (".chip 68060\n\t"
				    "cpushp %%dc,(%0)\n\t"
				    ".chip 68k"
				    : : "a" (paddr));
	      break;
	    case FLUSH_CACHE_INSN:
	      __asm__ __volatile__ (".chip 68060\n\t"
				    "cpushp %%ic,(%0)\n\t"
				    ".chip 68k"
				    : : "a" (paddr));
	      break;
	    default:
	    case FLUSH_CACHE_BOTH:
	      __asm__ __volatile__ (".chip 68060\n\t"
				    "cpushp %%bc,(%0)\n\t"
				    ".chip 68k"
				    : : "a" (paddr));
	      break;
	    }
	}
      break;
    }
  return 0;
}

/* sys_cacheflush -- flush (part of) the processor cache.  */
asmlinkage int
sys_cacheflush (unsigned long addr, int scope, int cache, unsigned long len)
{
	struct vm_area_struct *vma;
	int ret = -EINVAL;

	lock_kernel();
	if (scope < FLUSH_SCOPE_LINE || scope > FLUSH_SCOPE_ALL ||
	    cache & ~FLUSH_CACHE_BOTH)
		goto out;

	if (scope == FLUSH_SCOPE_ALL) {
		/* Only the superuser may explicitly flush the whole cache. */
		ret = -EPERM;
		if (!capable(CAP_SYS_ADMIN))
			goto out;
	} else {
		/*
		 * Verify that the specified address region actually belongs
		 * to this process.
		 */
		vma = find_vma (current->mm, addr);
		ret = -EINVAL;
		/* Check for overflow.  */
		if (addr + len < addr)
			goto out;
		if (vma == NULL || addr < vma->vm_start || addr + len > vma->vm_end)
			goto out;
	}

	if (CPU_IS_020_OR_030) {
		if (scope == FLUSH_SCOPE_LINE && len < 256) {
			unsigned long cacr;
			__asm__ ("movec %%cacr, %0" : "=r" (cacr));
			if (cache & FLUSH_CACHE_INSN)
				cacr |= 4;
			if (cache & FLUSH_CACHE_DATA)
				cacr |= 0x400;
			len >>= 2;
			while (len--) {
				__asm__ __volatile__ ("movec %1, %%caar\n\t"
						      "movec %0, %%cacr"
						      : /* no outputs */
						      : "r" (cacr), "r" (addr));
				addr += 4;
			}
		} else {
			/* Flush the whole cache, even if page granularity requested. */
			unsigned long cacr;
			__asm__ ("movec %%cacr, %0" : "=r" (cacr));
			if (cache & FLUSH_CACHE_INSN)
				cacr |= 8;
			if (cache & FLUSH_CACHE_DATA)
				cacr |= 0x800;
			__asm__ __volatile__ ("movec %0, %%cacr" : : "r" (cacr));
		}
		ret = 0;
		goto out;
	} else {
	    /*
	     * 040 or 060: don't blindly trust 'scope', someone could
	     * try to flush a few megs of memory.
	     */

	    if (len>=3*PAGE_SIZE && scope<FLUSH_SCOPE_PAGE)
	        scope=FLUSH_SCOPE_PAGE;
	    if (len>=10*PAGE_SIZE && scope<FLUSH_SCOPE_ALL)
	        scope=FLUSH_SCOPE_ALL;
	    if (CPU_IS_040) {
		ret = cache_flush_040 (addr, scope, cache, len);
	    } else if (CPU_IS_060) {
		ret = cache_flush_060 (addr, scope, cache, len);
	    }
	}
out:
	unlock_kernel();
	return ret;
}

asmlinkage int sys_getpagesize(void)
{
	return PAGE_SIZE;
}

/*
 * Do a system call from kernel instead of calling sys_execve so we
 * end up with proper pt_regs.
 */
int kernel_execve(const char *filename, char *const argv[], char *const envp[])
{
	register long __res asm ("%d0") = __NR_execve;
	register long __a asm ("%d1") = (long)(filename);
	register long __b asm ("%d2") = (long)(argv);
	register long __c asm ("%d3") = (long)(envp);
	asm volatile ("trap  #0" : "+d" (__res)
			: "d" (__a), "d" (__b), "d" (__c));
	return __res;
}

asmlinkage unsigned long sys_get_thread_area(void)
{
	return current_thread_info()->tp_value;
}

asmlinkage int sys_set_thread_area(unsigned long tp)
{
	current_thread_info()->tp_value = tp;
	return 0;
}

/* This syscall gets its arguments in A0 (mem), D2 (oldval) and
   D1 (newval).  */
asmlinkage int
sys_atomic_cmpxchg_32(unsigned long newval, int oldval, int d3, int d4, int d5,
		      unsigned long __user * mem)
{
	/* This was borrowed from ARM's implementation.  */
	for (;;) {
		struct mm_struct *mm = current->mm;
		pgd_t *pgd;
		pmd_t *pmd;
		pte_t *pte;
		spinlock_t *ptl;
		unsigned long mem_value;

		down_read(&mm->mmap_sem);
		pgd = pgd_offset(mm, (unsigned long)mem);
		if (!pgd_present(*pgd))
			goto bad_access;
		pmd = pmd_offset(pgd, (unsigned long)mem);
		if (!pmd_present(*pmd))
			goto bad_access;
		pte = pte_offset_map_lock(mm, pmd, (unsigned long)mem, &ptl);
		if (!pte_present(*pte) || !pte_dirty(*pte)
		    || !pte_write(*pte)) {
			pte_unmap_unlock(pte, ptl);
			goto bad_access;
		}

		mem_value = *mem;
		if (mem_value == oldval)
			*mem = newval;

		pte_unmap_unlock(pte, ptl);
		up_read(&mm->mmap_sem);
		return mem_value;

	      bad_access:
		up_read(&mm->mmap_sem);
		/* This is not necessarily a bad access, we can get here if
		   a memory we're trying to write to should be copied-on-write.
		   Make the kernel do the necessary page stuff, then re-iterate.
		   Simulate a write access fault to do that.  */
		{
			/* The first argument of the function corresponds to
			   D1, which is the first field of struct pt_regs.  */
			struct pt_regs *fp = (struct pt_regs *)&newval;

			/* '3' is an RMW flag.  */
			if (do_page_fault(fp, (unsigned long)mem, 3))
				/* If the do_page_fault() failed, we don't
				   have anything meaningful to return.
				   There should be a SIGSEGV pending for
				   the process.  */
				return 0xdeadbeef;
		}
	}
}

asmlinkage int sys_atomic_barrier(void)
{
	/* no code needed for uniprocs */
	return 0;
}