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/* Linux-specific atomic operations for PA Linux.
Copyright (C) 2008-2022 Free Software Foundation, Inc.
Based on code contributed by CodeSourcery for ARM EABI Linux.
Modifications for PA Linux by Helge Deller <deller@gmx.de>
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
#define EFAULT 14
#define EBUSY 16
#define ENOSYS 251
#define _ASM_EFAULT "-14"
typedef unsigned char u8;
typedef short unsigned int u16;
#ifdef __LP64__
typedef long unsigned int u64;
#else
typedef long long unsigned int u64;
#endif
/* PA-RISC 2.0 supports out-of-order execution for loads and stores.
Thus, we need to synchonize memory accesses. For more info, see:
"Advanced Performance Features of the 64-bit PA-8000" by Doug Hunt.
We implement byte, short and int versions of each atomic operation
using the kernel helper defined below. There is no support for
64-bit operations yet. */
/* Determine kernel LWS function call (0=32-bit, 1=64-bit userspace). */
#define LWS_CAS (sizeof(long) == 4 ? 0 : 1)
/* Kernel helper for compare-and-exchange a 32-bit value. */
static inline long
__kernel_cmpxchg (volatile void *mem, int oldval, int newval)
{
register unsigned long lws_mem asm("r26") = (unsigned long) (mem);
register int lws_old asm("r25") = oldval;
register int lws_new asm("r24") = newval;
register long lws_ret asm("r28");
register long lws_errno asm("r21");
asm volatile ( "ble 0xb0(%%sr2, %%r0) \n\t"
"ldi %2, %%r20 \n\t"
"cmpiclr,<> " _ASM_EFAULT ", %%r21, %%r0\n\t"
"iitlbp %%r0,(%%sr0, %%r0) \n\t"
: "=r" (lws_ret), "=r" (lws_errno)
: "i" (LWS_CAS), "r" (lws_mem), "r" (lws_old), "r" (lws_new)
: "r1", "r20", "r22", "r23", "r29", "r31", "memory"
);
/* If the kernel LWS call succeeded (lws_errno == 0), lws_ret contains
the old value from memory. If this value is equal to OLDVAL, the
new value was written to memory. If not, return -EBUSY. */
if (!lws_errno && lws_ret != oldval)
return -EBUSY;
return lws_errno;
}
static inline long
__kernel_cmpxchg2 (volatile void *mem, const void *oldval, const void *newval,
int val_size)
{
register unsigned long lws_mem asm("r26") = (unsigned long) (mem);
register unsigned long lws_old asm("r25") = (unsigned long) oldval;
register unsigned long lws_new asm("r24") = (unsigned long) newval;
register int lws_size asm("r23") = val_size;
register long lws_ret asm("r28");
register long lws_errno asm("r21");
asm volatile ( "ble 0xb0(%%sr2, %%r0) \n\t"
"ldi %6, %%r20 \n\t"
"cmpiclr,<> " _ASM_EFAULT ", %%r21, %%r0\n\t"
"iitlbp %%r0,(%%sr0, %%r0) \n\t"
: "=r" (lws_ret), "=r" (lws_errno), "+r" (lws_mem),
"+r" (lws_old), "+r" (lws_new), "+r" (lws_size)
: "i" (2)
: "r1", "r20", "r22", "r29", "r31", "fr4", "memory"
);
/* If the kernel LWS call is successful, lws_ret contains 0. */
if (__builtin_expect (lws_ret == 0, 1))
return 0;
/* If the kernel LWS call fails with no error, return -EBUSY */
if (__builtin_expect (!lws_errno, 0))
return -EBUSY;
return lws_errno;
}
#define HIDDEN __attribute__ ((visibility ("hidden")))
/* Big endian masks */
#define INVERT_MASK_1 24
#define INVERT_MASK_2 16
#define MASK_1 0xffu
#define MASK_2 0xffffu
#define FETCH_AND_OP_2(OP, PFX_OP, INF_OP, TYPE, WIDTH, INDEX) \
TYPE HIDDEN \
__sync_fetch_and_##OP##_##WIDTH (volatile void *ptr, TYPE val) \
{ \
TYPE tmp, newval; \
long failure; \
\
do { \
tmp = __atomic_load_n ((volatile TYPE *)ptr, __ATOMIC_RELAXED); \
newval = PFX_OP (tmp INF_OP val); \
failure = __kernel_cmpxchg2 (ptr, &tmp, &newval, INDEX); \
} while (failure != 0); \
\
return tmp; \
}
FETCH_AND_OP_2 (add, , +, u64, 8, 3)
FETCH_AND_OP_2 (sub, , -, u64, 8, 3)
FETCH_AND_OP_2 (or, , |, u64, 8, 3)
FETCH_AND_OP_2 (and, , &, u64, 8, 3)
FETCH_AND_OP_2 (xor, , ^, u64, 8, 3)
FETCH_AND_OP_2 (nand, ~, &, u64, 8, 3)
FETCH_AND_OP_2 (add, , +, u16, 2, 1)
FETCH_AND_OP_2 (sub, , -, u16, 2, 1)
FETCH_AND_OP_2 (or, , |, u16, 2, 1)
FETCH_AND_OP_2 (and, , &, u16, 2, 1)
FETCH_AND_OP_2 (xor, , ^, u16, 2, 1)
FETCH_AND_OP_2 (nand, ~, &, u16, 2, 1)
FETCH_AND_OP_2 (add, , +, u8, 1, 0)
FETCH_AND_OP_2 (sub, , -, u8, 1, 0)
FETCH_AND_OP_2 (or, , |, u8, 1, 0)
FETCH_AND_OP_2 (and, , &, u8, 1, 0)
FETCH_AND_OP_2 (xor, , ^, u8, 1, 0)
FETCH_AND_OP_2 (nand, ~, &, u8, 1, 0)
#define OP_AND_FETCH_2(OP, PFX_OP, INF_OP, TYPE, WIDTH, INDEX) \
TYPE HIDDEN \
__sync_##OP##_and_fetch_##WIDTH (volatile void *ptr, TYPE val) \
{ \
TYPE tmp, newval; \
long failure; \
\
do { \
tmp = __atomic_load_n ((volatile TYPE *)ptr, __ATOMIC_RELAXED); \
newval = PFX_OP (tmp INF_OP val); \
failure = __kernel_cmpxchg2 (ptr, &tmp, &newval, INDEX); \
} while (failure != 0); \
\
return PFX_OP (tmp INF_OP val); \
}
OP_AND_FETCH_2 (add, , +, u64, 8, 3)
OP_AND_FETCH_2 (sub, , -, u64, 8, 3)
OP_AND_FETCH_2 (or, , |, u64, 8, 3)
OP_AND_FETCH_2 (and, , &, u64, 8, 3)
OP_AND_FETCH_2 (xor, , ^, u64, 8, 3)
OP_AND_FETCH_2 (nand, ~, &, u64, 8, 3)
OP_AND_FETCH_2 (add, , +, u16, 2, 1)
OP_AND_FETCH_2 (sub, , -, u16, 2, 1)
OP_AND_FETCH_2 (or, , |, u16, 2, 1)
OP_AND_FETCH_2 (and, , &, u16, 2, 1)
OP_AND_FETCH_2 (xor, , ^, u16, 2, 1)
OP_AND_FETCH_2 (nand, ~, &, u16, 2, 1)
OP_AND_FETCH_2 (add, , +, u8, 1, 0)
OP_AND_FETCH_2 (sub, , -, u8, 1, 0)
OP_AND_FETCH_2 (or, , |, u8, 1, 0)
OP_AND_FETCH_2 (and, , &, u8, 1, 0)
OP_AND_FETCH_2 (xor, , ^, u8, 1, 0)
OP_AND_FETCH_2 (nand, ~, &, u8, 1, 0)
#define FETCH_AND_OP_WORD(OP, PFX_OP, INF_OP) \
unsigned int HIDDEN \
__sync_fetch_and_##OP##_4 (volatile void *ptr, unsigned int val) \
{ \
unsigned int tmp; \
long failure; \
\
do { \
tmp = __atomic_load_n ((volatile unsigned int *)ptr, \
__ATOMIC_RELAXED); \
failure = __kernel_cmpxchg (ptr, tmp, PFX_OP (tmp INF_OP val)); \
} while (failure != 0); \
\
return tmp; \
}
FETCH_AND_OP_WORD (add, , +)
FETCH_AND_OP_WORD (sub, , -)
FETCH_AND_OP_WORD (or, , |)
FETCH_AND_OP_WORD (and, , &)
FETCH_AND_OP_WORD (xor, , ^)
FETCH_AND_OP_WORD (nand, ~, &)
#define OP_AND_FETCH_WORD(OP, PFX_OP, INF_OP) \
unsigned int HIDDEN \
__sync_##OP##_and_fetch_4 (volatile void *ptr, unsigned int val) \
{ \
unsigned int tmp; \
long failure; \
\
do { \
tmp = __atomic_load_n ((volatile unsigned int *)ptr, \
__ATOMIC_RELAXED); \
failure = __kernel_cmpxchg (ptr, tmp, PFX_OP (tmp INF_OP val)); \
} while (failure != 0); \
\
return PFX_OP (tmp INF_OP val); \
}
OP_AND_FETCH_WORD (add, , +)
OP_AND_FETCH_WORD (sub, , -)
OP_AND_FETCH_WORD (or, , |)
OP_AND_FETCH_WORD (and, , &)
OP_AND_FETCH_WORD (xor, , ^)
OP_AND_FETCH_WORD (nand, ~, &)
typedef unsigned char bool;
#define COMPARE_AND_SWAP_2(TYPE, WIDTH, INDEX) \
TYPE HIDDEN \
__sync_val_compare_and_swap_##WIDTH (volatile void *ptr, TYPE oldval, \
TYPE newval) \
{ \
TYPE actual_oldval; \
long fail; \
\
while (1) \
{ \
actual_oldval = __atomic_load_n ((volatile TYPE *)ptr, \
__ATOMIC_RELAXED); \
\
if (__builtin_expect (oldval != actual_oldval, 0)) \
return actual_oldval; \
\
fail = __kernel_cmpxchg2 (ptr, &actual_oldval, &newval, INDEX); \
\
if (__builtin_expect (!fail, 1)) \
return actual_oldval; \
} \
} \
\
_Bool HIDDEN \
__sync_bool_compare_and_swap_##WIDTH (volatile void *ptr, \
TYPE oldval, TYPE newval) \
{ \
long failure = __kernel_cmpxchg2 (ptr, &oldval, &newval, INDEX); \
return (failure == 0); \
}
COMPARE_AND_SWAP_2 (u64, 8, 3)
COMPARE_AND_SWAP_2 (u16, 2, 1)
COMPARE_AND_SWAP_2 (u8, 1, 0)
unsigned int HIDDEN
__sync_val_compare_and_swap_4 (volatile void *ptr, unsigned int oldval,
unsigned int newval)
{
long fail;
unsigned int actual_oldval;
while (1)
{
actual_oldval = __atomic_load_n ((volatile unsigned int *)ptr,
__ATOMIC_RELAXED);
if (__builtin_expect (oldval != actual_oldval, 0))
return actual_oldval;
fail = __kernel_cmpxchg (ptr, actual_oldval, newval);
if (__builtin_expect (!fail, 1))
return actual_oldval;
}
}
_Bool HIDDEN
__sync_bool_compare_and_swap_4 (volatile void *ptr, unsigned int oldval,
unsigned int newval)
{
long failure = __kernel_cmpxchg (ptr, oldval, newval);
return (failure == 0);
}
#define SYNC_LOCK_TEST_AND_SET_2(TYPE, WIDTH, INDEX) \
TYPE HIDDEN \
__sync_lock_test_and_set_##WIDTH (volatile void *ptr, TYPE val) \
{ \
TYPE oldval; \
long failure; \
\
do { \
oldval = __atomic_load_n ((volatile TYPE *)ptr, \
__ATOMIC_RELAXED); \
failure = __kernel_cmpxchg2 (ptr, &oldval, &val, INDEX); \
} while (failure != 0); \
\
return oldval; \
}
SYNC_LOCK_TEST_AND_SET_2 (u64, 8, 3)
SYNC_LOCK_TEST_AND_SET_2 (u16, 2, 1)
SYNC_LOCK_TEST_AND_SET_2 (u8, 1, 0)
unsigned int HIDDEN
__sync_lock_test_and_set_4 (volatile void *ptr, unsigned int val)
{
long failure;
unsigned int oldval;
do {
oldval = __atomic_load_n ((volatile unsigned int *)ptr, __ATOMIC_RELAXED);
failure = __kernel_cmpxchg (ptr, oldval, val);
} while (failure != 0);
return oldval;
}
#define SYNC_LOCK_RELEASE_1(TYPE, WIDTH, INDEX) \
void HIDDEN \
__sync_lock_release_##WIDTH (volatile void *ptr) \
{ \
TYPE oldval, val = 0; \
long failure; \
\
do { \
oldval = __atomic_load_n ((volatile TYPE *)ptr, \
__ATOMIC_RELAXED); \
failure = __kernel_cmpxchg2 (ptr, &oldval, &val, INDEX); \
} while (failure != 0); \
}
SYNC_LOCK_RELEASE_1 (u64, 8, 3)
SYNC_LOCK_RELEASE_1 (u16, 2, 1)
SYNC_LOCK_RELEASE_1 (u8, 1, 0)
void HIDDEN
__sync_lock_release_4 (volatile void *ptr)
{
long failure;
unsigned int oldval;
do {
oldval = __atomic_load_n ((volatile unsigned int *)ptr, __ATOMIC_RELAXED);
failure = __kernel_cmpxchg (ptr, oldval, 0);
} while (failure != 0);
}
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