root/arch/c6x/include/asm/cmpxchg.h

INCLUDED FROM

DEFINITIONS

1. __xchg

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  *  Port on Texas Instruments TMS320C6x architecture
   4  *
   5  *  Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
   6  *  Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
   7  */
   8 #ifndef _ASM_C6X_CMPXCHG_H
   9 #define _ASM_C6X_CMPXCHG_H
  10 
  11 #include <linux/irqflags.h>
  12 
  13 /*
  14  * Misc. functions
  15  */
  16 static inline unsigned int __xchg(unsigned int x, volatile void *ptr, int size)
  17 {
  18         unsigned int tmp;
  19         unsigned long flags;
  20 
  21         local_irq_save(flags);
  22 
  23         switch (size) {
  24         case 1:
  25                 tmp = 0;
  26                 tmp = *((unsigned char *) ptr);
  27                 *((unsigned char *) ptr) = (unsigned char) x;
  28                 break;
  29         case 2:
  30                 tmp = 0;
  31                 tmp = *((unsigned short *) ptr);
  32                 *((unsigned short *) ptr) = x;
  33                 break;
  34         case 4:
  35                 tmp = 0;
  36                 tmp = *((unsigned int *) ptr);
  37                 *((unsigned int *) ptr) = x;
  38                 break;
  39         }
  40         local_irq_restore(flags);
  41         return tmp;
  42 }
  43 
  44 #define xchg(ptr, x) \
  45         ((__typeof__(*(ptr)))__xchg((unsigned int)(x), (void *) (ptr), \
  46                                     sizeof(*(ptr))))
  47 
  48 #include <asm-generic/cmpxchg-local.h>
  49 
  50 /*
  51  * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
  52  * them available.
  53  */
  54 #define cmpxchg_local(ptr, o, n)                                        \
  55         ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr),             \
  56                                                      (unsigned long)(o), \
  57                                                      (unsigned long)(n), \
  58                                                      sizeof(*(ptr))))
  59 #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
  60 
  61 #include <asm-generic/cmpxchg.h>
  62 
  63 #endif /* _ASM_C6X_CMPXCHG_H */