| 1 |
734 |
jeremybenn |
/* Linux-specific atomic operations for PA Linux.
|
| 2 |
|
|
Copyright (C) 2008, 2009, 2010 Free Software Foundation, Inc.
|
| 3 |
|
|
Based on code contributed by CodeSourcery for ARM EABI Linux.
|
| 4 |
|
|
Modifications for PA Linux by Helge Deller <deller@gmx.de>
|
| 5 |
|
|
|
| 6 |
|
|
This file is part of GCC.
|
| 7 |
|
|
|
| 8 |
|
|
GCC is free software; you can redistribute it and/or modify it under
|
| 9 |
|
|
the terms of the GNU General Public License as published by the Free
|
| 10 |
|
|
Software Foundation; either version 3, or (at your option) any later
|
| 11 |
|
|
version.
|
| 12 |
|
|
|
| 13 |
|
|
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
|
| 14 |
|
|
WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
| 15 |
|
|
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
| 16 |
|
|
for more details.
|
| 17 |
|
|
|
| 18 |
|
|
Under Section 7 of GPL version 3, you are granted additional
|
| 19 |
|
|
permissions described in the GCC Runtime Library Exception, version
|
| 20 |
|
|
3.1, as published by the Free Software Foundation.
|
| 21 |
|
|
|
| 22 |
|
|
You should have received a copy of the GNU General Public License and
|
| 23 |
|
|
a copy of the GCC Runtime Library Exception along with this program;
|
| 24 |
|
|
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
|
| 25 |
|
|
<http://www.gnu.org/licenses/>. */
|
| 26 |
|
|
|
| 27 |
|
|
#define EFAULT 14
|
| 28 |
|
|
#define EBUSY 16
|
| 29 |
|
|
#define ENOSYS 251
|
| 30 |
|
|
|
| 31 |
|
|
/* All PA-RISC implementations supported by linux have strongly
|
| 32 |
|
|
ordered loads and stores. Only cache flushes and purges can be
|
| 33 |
|
|
delayed. The data cache implementations are all globally
|
| 34 |
|
|
coherent. Thus, there is no need to synchonize memory accesses.
|
| 35 |
|
|
|
| 36 |
|
|
GCC automatically issues a asm memory barrier when it encounters
|
| 37 |
|
|
a __sync_synchronize builtin. Thus, we do not need to define this
|
| 38 |
|
|
builtin.
|
| 39 |
|
|
|
| 40 |
|
|
We implement byte, short and int versions of each atomic operation
|
| 41 |
|
|
using the kernel helper defined below. There is no support for
|
| 42 |
|
|
64-bit operations yet. */
|
| 43 |
|
|
|
| 44 |
|
|
/* A privileged instruction to crash a userspace program with SIGILL. */
|
| 45 |
|
|
#define ABORT_INSTRUCTION asm ("iitlbp %r0,(%sr0, %r0)")
|
| 46 |
|
|
|
| 47 |
|
|
/* Determine kernel LWS function call (0=32-bit, 1=64-bit userspace). */
|
| 48 |
|
|
#define LWS_CAS (sizeof(unsigned long) == 4 ? 0 : 1)
|
| 49 |
|
|
|
| 50 |
|
|
/* Kernel helper for compare-and-exchange a 32-bit value. */
|
| 51 |
|
|
static inline long
|
| 52 |
|
|
__kernel_cmpxchg (int oldval, int newval, int *mem)
|
| 53 |
|
|
{
|
| 54 |
|
|
register unsigned long lws_mem asm("r26") = (unsigned long) (mem);
|
| 55 |
|
|
register long lws_ret asm("r28");
|
| 56 |
|
|
register long lws_errno asm("r21");
|
| 57 |
|
|
register int lws_old asm("r25") = oldval;
|
| 58 |
|
|
register int lws_new asm("r24") = newval;
|
| 59 |
|
|
asm volatile ( "ble 0xb0(%%sr2, %%r0) \n\t"
|
| 60 |
|
|
"ldi %5, %%r20 \n\t"
|
| 61 |
|
|
: "=r" (lws_ret), "=r" (lws_errno), "=r" (lws_mem),
|
| 62 |
|
|
"=r" (lws_old), "=r" (lws_new)
|
| 63 |
|
|
: "i" (LWS_CAS), "2" (lws_mem), "3" (lws_old), "4" (lws_new)
|
| 64 |
|
|
: "r1", "r20", "r22", "r23", "r29", "r31", "memory"
|
| 65 |
|
|
);
|
| 66 |
|
|
if (__builtin_expect (lws_errno == -EFAULT || lws_errno == -ENOSYS, 0))
|
| 67 |
|
|
ABORT_INSTRUCTION;
|
| 68 |
|
|
|
| 69 |
|
|
/* If the kernel LWS call succeeded (lws_errno == 0), lws_ret contains
|
| 70 |
|
|
the old value from memory. If this value is equal to OLDVAL, the
|
| 71 |
|
|
new value was written to memory. If not, return -EBUSY. */
|
| 72 |
|
|
if (!lws_errno && lws_ret != oldval)
|
| 73 |
|
|
lws_errno = -EBUSY;
|
| 74 |
|
|
|
| 75 |
|
|
return lws_errno;
|
| 76 |
|
|
}
|
| 77 |
|
|
|
| 78 |
|
|
#define HIDDEN __attribute__ ((visibility ("hidden")))
|
| 79 |
|
|
|
| 80 |
|
|
/* Big endian masks */
|
| 81 |
|
|
#define INVERT_MASK_1 24
|
| 82 |
|
|
#define INVERT_MASK_2 16
|
| 83 |
|
|
|
| 84 |
|
|
#define MASK_1 0xffu
|
| 85 |
|
|
#define MASK_2 0xffffu
|
| 86 |
|
|
|
| 87 |
|
|
#define FETCH_AND_OP_WORD(OP, PFX_OP, INF_OP) \
|
| 88 |
|
|
int HIDDEN \
|
| 89 |
|
|
__sync_fetch_and_##OP##_4 (int *ptr, int val) \
|
| 90 |
|
|
{ \
|
| 91 |
|
|
int failure, tmp; \
|
| 92 |
|
|
\
|
| 93 |
|
|
do { \
|
| 94 |
|
|
tmp = *ptr; \
|
| 95 |
|
|
failure = __kernel_cmpxchg (tmp, PFX_OP (tmp INF_OP val), ptr); \
|
| 96 |
|
|
} while (failure != 0); \
|
| 97 |
|
|
\
|
| 98 |
|
|
return tmp; \
|
| 99 |
|
|
}
|
| 100 |
|
|
|
| 101 |
|
|
FETCH_AND_OP_WORD (add, , +)
|
| 102 |
|
|
FETCH_AND_OP_WORD (sub, , -)
|
| 103 |
|
|
FETCH_AND_OP_WORD (or, , |)
|
| 104 |
|
|
FETCH_AND_OP_WORD (and, , &)
|
| 105 |
|
|
FETCH_AND_OP_WORD (xor, , ^)
|
| 106 |
|
|
FETCH_AND_OP_WORD (nand, ~, &)
|
| 107 |
|
|
|
| 108 |
|
|
#define NAME_oldval(OP, WIDTH) __sync_fetch_and_##OP##_##WIDTH
|
| 109 |
|
|
#define NAME_newval(OP, WIDTH) __sync_##OP##_and_fetch_##WIDTH
|
| 110 |
|
|
|
| 111 |
|
|
/* Implement both __sync_<op>_and_fetch and __sync_fetch_and_<op> for
|
| 112 |
|
|
subword-sized quantities. */
|
| 113 |
|
|
|
| 114 |
|
|
#define SUBWORD_SYNC_OP(OP, PFX_OP, INF_OP, TYPE, WIDTH, RETURN) \
|
| 115 |
|
|
TYPE HIDDEN \
|
| 116 |
|
|
NAME##_##RETURN (OP, WIDTH) (TYPE *ptr, TYPE val) \
|
| 117 |
|
|
{ \
|
| 118 |
|
|
int *wordptr = (int *) ((unsigned long) ptr & ~3); \
|
| 119 |
|
|
unsigned int mask, shift, oldval, newval; \
|
| 120 |
|
|
int failure; \
|
| 121 |
|
|
\
|
| 122 |
|
|
shift = (((unsigned long) ptr & 3) << 3) ^ INVERT_MASK_##WIDTH; \
|
| 123 |
|
|
mask = MASK_##WIDTH << shift; \
|
| 124 |
|
|
\
|
| 125 |
|
|
do { \
|
| 126 |
|
|
oldval = *wordptr; \
|
| 127 |
|
|
newval = ((PFX_OP (((oldval & mask) >> shift) \
|
| 128 |
|
|
INF_OP (unsigned int) val)) << shift) & mask; \
|
| 129 |
|
|
newval |= oldval & ~mask; \
|
| 130 |
|
|
failure = __kernel_cmpxchg (oldval, newval, wordptr); \
|
| 131 |
|
|
} while (failure != 0); \
|
| 132 |
|
|
\
|
| 133 |
|
|
return (RETURN & mask) >> shift; \
|
| 134 |
|
|
}
|
| 135 |
|
|
|
| 136 |
|
|
SUBWORD_SYNC_OP (add, , +, unsigned short, 2, oldval)
|
| 137 |
|
|
SUBWORD_SYNC_OP (sub, , -, unsigned short, 2, oldval)
|
| 138 |
|
|
SUBWORD_SYNC_OP (or, , |, unsigned short, 2, oldval)
|
| 139 |
|
|
SUBWORD_SYNC_OP (and, , &, unsigned short, 2, oldval)
|
| 140 |
|
|
SUBWORD_SYNC_OP (xor, , ^, unsigned short, 2, oldval)
|
| 141 |
|
|
SUBWORD_SYNC_OP (nand, ~, &, unsigned short, 2, oldval)
|
| 142 |
|
|
|
| 143 |
|
|
SUBWORD_SYNC_OP (add, , +, unsigned char, 1, oldval)
|
| 144 |
|
|
SUBWORD_SYNC_OP (sub, , -, unsigned char, 1, oldval)
|
| 145 |
|
|
SUBWORD_SYNC_OP (or, , |, unsigned char, 1, oldval)
|
| 146 |
|
|
SUBWORD_SYNC_OP (and, , &, unsigned char, 1, oldval)
|
| 147 |
|
|
SUBWORD_SYNC_OP (xor, , ^, unsigned char, 1, oldval)
|
| 148 |
|
|
SUBWORD_SYNC_OP (nand, ~, &, unsigned char, 1, oldval)
|
| 149 |
|
|
|
| 150 |
|
|
#define OP_AND_FETCH_WORD(OP, PFX_OP, INF_OP) \
|
| 151 |
|
|
int HIDDEN \
|
| 152 |
|
|
__sync_##OP##_and_fetch_4 (int *ptr, int val) \
|
| 153 |
|
|
{ \
|
| 154 |
|
|
int tmp, failure; \
|
| 155 |
|
|
\
|
| 156 |
|
|
do { \
|
| 157 |
|
|
tmp = *ptr; \
|
| 158 |
|
|
failure = __kernel_cmpxchg (tmp, PFX_OP (tmp INF_OP val), ptr); \
|
| 159 |
|
|
} while (failure != 0); \
|
| 160 |
|
|
\
|
| 161 |
|
|
return PFX_OP (tmp INF_OP val); \
|
| 162 |
|
|
}
|
| 163 |
|
|
|
| 164 |
|
|
OP_AND_FETCH_WORD (add, , +)
|
| 165 |
|
|
OP_AND_FETCH_WORD (sub, , -)
|
| 166 |
|
|
OP_AND_FETCH_WORD (or, , |)
|
| 167 |
|
|
OP_AND_FETCH_WORD (and, , &)
|
| 168 |
|
|
OP_AND_FETCH_WORD (xor, , ^)
|
| 169 |
|
|
OP_AND_FETCH_WORD (nand, ~, &)
|
| 170 |
|
|
|
| 171 |
|
|
SUBWORD_SYNC_OP (add, , +, unsigned short, 2, newval)
|
| 172 |
|
|
SUBWORD_SYNC_OP (sub, , -, unsigned short, 2, newval)
|
| 173 |
|
|
SUBWORD_SYNC_OP (or, , |, unsigned short, 2, newval)
|
| 174 |
|
|
SUBWORD_SYNC_OP (and, , &, unsigned short, 2, newval)
|
| 175 |
|
|
SUBWORD_SYNC_OP (xor, , ^, unsigned short, 2, newval)
|
| 176 |
|
|
SUBWORD_SYNC_OP (nand, ~, &, unsigned short, 2, newval)
|
| 177 |
|
|
|
| 178 |
|
|
SUBWORD_SYNC_OP (add, , +, unsigned char, 1, newval)
|
| 179 |
|
|
SUBWORD_SYNC_OP (sub, , -, unsigned char, 1, newval)
|
| 180 |
|
|
SUBWORD_SYNC_OP (or, , |, unsigned char, 1, newval)
|
| 181 |
|
|
SUBWORD_SYNC_OP (and, , &, unsigned char, 1, newval)
|
| 182 |
|
|
SUBWORD_SYNC_OP (xor, , ^, unsigned char, 1, newval)
|
| 183 |
|
|
SUBWORD_SYNC_OP (nand, ~, &, unsigned char, 1, newval)
|
| 184 |
|
|
|
| 185 |
|
|
int HIDDEN
|
| 186 |
|
|
__sync_val_compare_and_swap_4 (int *ptr, int oldval, int newval)
|
| 187 |
|
|
{
|
| 188 |
|
|
int actual_oldval, fail;
|
| 189 |
|
|
|
| 190 |
|
|
while (1)
|
| 191 |
|
|
{
|
| 192 |
|
|
actual_oldval = *ptr;
|
| 193 |
|
|
|
| 194 |
|
|
if (__builtin_expect (oldval != actual_oldval, 0))
|
| 195 |
|
|
return actual_oldval;
|
| 196 |
|
|
|
| 197 |
|
|
fail = __kernel_cmpxchg (actual_oldval, newval, ptr);
|
| 198 |
|
|
|
| 199 |
|
|
if (__builtin_expect (!fail, 1))
|
| 200 |
|
|
return actual_oldval;
|
| 201 |
|
|
}
|
| 202 |
|
|
}
|
| 203 |
|
|
|
| 204 |
|
|
#define SUBWORD_VAL_CAS(TYPE, WIDTH) \
|
| 205 |
|
|
TYPE HIDDEN \
|
| 206 |
|
|
__sync_val_compare_and_swap_##WIDTH (TYPE *ptr, TYPE oldval, \
|
| 207 |
|
|
TYPE newval) \
|
| 208 |
|
|
{ \
|
| 209 |
|
|
int *wordptr = (int *)((unsigned long) ptr & ~3), fail; \
|
| 210 |
|
|
unsigned int mask, shift, actual_oldval, actual_newval; \
|
| 211 |
|
|
\
|
| 212 |
|
|
shift = (((unsigned long) ptr & 3) << 3) ^ INVERT_MASK_##WIDTH; \
|
| 213 |
|
|
mask = MASK_##WIDTH << shift; \
|
| 214 |
|
|
\
|
| 215 |
|
|
while (1) \
|
| 216 |
|
|
{ \
|
| 217 |
|
|
actual_oldval = *wordptr; \
|
| 218 |
|
|
\
|
| 219 |
|
|
if (__builtin_expect (((actual_oldval & mask) >> shift) \
|
| 220 |
|
|
!= (unsigned int) oldval, 0)) \
|
| 221 |
|
|
return (actual_oldval & mask) >> shift; \
|
| 222 |
|
|
\
|
| 223 |
|
|
actual_newval = (actual_oldval & ~mask) \
|
| 224 |
|
|
| (((unsigned int) newval << shift) & mask); \
|
| 225 |
|
|
\
|
| 226 |
|
|
fail = __kernel_cmpxchg (actual_oldval, actual_newval, \
|
| 227 |
|
|
wordptr); \
|
| 228 |
|
|
\
|
| 229 |
|
|
if (__builtin_expect (!fail, 1)) \
|
| 230 |
|
|
return (actual_oldval & mask) >> shift; \
|
| 231 |
|
|
} \
|
| 232 |
|
|
}
|
| 233 |
|
|
|
| 234 |
|
|
SUBWORD_VAL_CAS (unsigned short, 2)
|
| 235 |
|
|
SUBWORD_VAL_CAS (unsigned char, 1)
|
| 236 |
|
|
|
| 237 |
|
|
typedef unsigned char bool;
|
| 238 |
|
|
|
| 239 |
|
|
bool HIDDEN
|
| 240 |
|
|
__sync_bool_compare_and_swap_4 (int *ptr, int oldval, int newval)
|
| 241 |
|
|
{
|
| 242 |
|
|
int failure = __kernel_cmpxchg (oldval, newval, ptr);
|
| 243 |
|
|
return (failure == 0);
|
| 244 |
|
|
}
|
| 245 |
|
|
|
| 246 |
|
|
#define SUBWORD_BOOL_CAS(TYPE, WIDTH) \
|
| 247 |
|
|
bool HIDDEN \
|
| 248 |
|
|
__sync_bool_compare_and_swap_##WIDTH (TYPE *ptr, TYPE oldval, \
|
| 249 |
|
|
TYPE newval) \
|
| 250 |
|
|
{ \
|
| 251 |
|
|
TYPE actual_oldval \
|
| 252 |
|
|
= __sync_val_compare_and_swap_##WIDTH (ptr, oldval, newval); \
|
| 253 |
|
|
return (oldval == actual_oldval); \
|
| 254 |
|
|
}
|
| 255 |
|
|
|
| 256 |
|
|
SUBWORD_BOOL_CAS (unsigned short, 2)
|
| 257 |
|
|
SUBWORD_BOOL_CAS (unsigned char, 1)
|
| 258 |
|
|
|
| 259 |
|
|
int HIDDEN
|
| 260 |
|
|
__sync_lock_test_and_set_4 (int *ptr, int val)
|
| 261 |
|
|
{
|
| 262 |
|
|
int failure, oldval;
|
| 263 |
|
|
|
| 264 |
|
|
do {
|
| 265 |
|
|
oldval = *ptr;
|
| 266 |
|
|
failure = __kernel_cmpxchg (oldval, val, ptr);
|
| 267 |
|
|
} while (failure != 0);
|
| 268 |
|
|
|
| 269 |
|
|
return oldval;
|
| 270 |
|
|
}
|
| 271 |
|
|
|
| 272 |
|
|
#define SUBWORD_TEST_AND_SET(TYPE, WIDTH) \
|
| 273 |
|
|
TYPE HIDDEN \
|
| 274 |
|
|
__sync_lock_test_and_set_##WIDTH (TYPE *ptr, TYPE val) \
|
| 275 |
|
|
{ \
|
| 276 |
|
|
int failure; \
|
| 277 |
|
|
unsigned int oldval, newval, shift, mask; \
|
| 278 |
|
|
int *wordptr = (int *) ((unsigned long) ptr & ~3); \
|
| 279 |
|
|
\
|
| 280 |
|
|
shift = (((unsigned long) ptr & 3) << 3) ^ INVERT_MASK_##WIDTH; \
|
| 281 |
|
|
mask = MASK_##WIDTH << shift; \
|
| 282 |
|
|
\
|
| 283 |
|
|
do { \
|
| 284 |
|
|
oldval = *wordptr; \
|
| 285 |
|
|
newval = (oldval & ~mask) \
|
| 286 |
|
|
| (((unsigned int) val << shift) & mask); \
|
| 287 |
|
|
failure = __kernel_cmpxchg (oldval, newval, wordptr); \
|
| 288 |
|
|
} while (failure != 0); \
|
| 289 |
|
|
\
|
| 290 |
|
|
return (oldval & mask) >> shift; \
|
| 291 |
|
|
}
|
| 292 |
|
|
|
| 293 |
|
|
SUBWORD_TEST_AND_SET (unsigned short, 2)
|
| 294 |
|
|
SUBWORD_TEST_AND_SET (unsigned char, 1)
|
| 295 |
|
|
|
| 296 |
|
|
#define SYNC_LOCK_RELEASE(TYPE, WIDTH) \
|
| 297 |
|
|
void HIDDEN \
|
| 298 |
|
|
__sync_lock_release_##WIDTH (TYPE *ptr) \
|
| 299 |
|
|
{ \
|
| 300 |
|
|
*ptr = 0; \
|
| 301 |
|
|
}
|
| 302 |
|
|
|
| 303 |
|
|
SYNC_LOCK_RELEASE (int, 4)
|
| 304 |
|
|
SYNC_LOCK_RELEASE (short, 2)
|
| 305 |
|
|
SYNC_LOCK_RELEASE (char, 1)
|
