1 /*
2 * Copyright (C) 2016-2017 Andes Technology, Inc.
3 * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
4 */
5
6 /* Machine-dependent pthreads configuration and inline functions.
7 Copyright (C) 1997, 1998, 2000, 2002, 2003 Free Software Foundation, Inc.
8 Contributed by Philip Blundell <philb@gnu.org>.
9
10 The GNU C Library is free software; you can redistribute it and/or
11 modify it under the terms of the GNU Lesser General Public License as
12 published by the Free Software Foundation; either version 2.1 of the
13 License, or (at your option) any later version.
14
15 The GNU C Library is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 Lesser General Public License for more details.
19
20 You should have received a copy of the GNU Lesser General Public
21 License along with the GNU C Library; see the file COPYING.LIB. If not,
22 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 Boston, MA 02111-1307, USA. */
24
25 #ifndef _PT_MACHINE_H
26 #define _PT_MACHINE_H 1
27
28 #include <features.h>
29
30 #ifndef PT_EI
31 # define PT_EI __extern_always_inline
32 #endif
33
34 extern long int testandset (int *spinlock);
35 extern int __compare_and_swap (long int *p, long int oldval, long int newval);
36
37 /* Spinlock implementation; required. */
38 PT_EI long int
testandset(int * spinlock)39 testandset (int *spinlock)
40 {
41 unsigned int val;
42 unsigned int temp;
43 unsigned int offset = 0;
44
45 __asm__ __volatile__ (
46 "1:\n\t"
47 "llw %[val], [%[spinlock] + %[offset] << 0]\n\t"
48 "move %[temp], #0x1\n\t"
49 "beq %[val], %[temp], 2f\n\t"
50 "scw %[temp], [%[spinlock] + %[offset] << 0]\n\t"
51 "beqz %[temp], 1b\n\t"
52 "2:\n\t"
53 : [val] "=&r" (val), [temp] "=&r" (temp)
54 : [spinlock] "r" (spinlock), [offset] "r" (offset)
55 : "memory" ) ;
56
57 return val ;
58 }
59
60
61 /* Get some notion of the current stack. Need not be exactly the top
62 of the stack, just something somewhere in the current frame. */
63 #define CURRENT_STACK_FRAME stack_pointer
64 register char * stack_pointer __asm__ ("$sp");
65
66 #endif /* pt-machine.h */
67