/* * include/asm-v850/system.h -- Low-level interrupt/thread ops * * Copyright (C) 2001,02,03 NEC Electronics Corporation * Copyright (C) 2001,02,03 Miles Bader <miles@gnu.org> * * This file is subject to the terms and conditions of the GNU General * Public License. See the file COPYING in the main directory of this * archive for more details. * * Written by Miles Bader <miles@gnu.org> */ #ifndef __V850_SYSTEM_H__ #define __V850_SYSTEM_H__ #include <linux/linkage.h> #include <asm/ptrace.h> /* * switch_to(n) should switch tasks to task ptr, first checking that * ptr isn't the current task, in which case it does nothing. */ struct thread_struct; extern void *switch_thread (struct thread_struct *last, struct thread_struct *next); #define switch_to(prev,next,last) \ do { \ if (prev != next) { \ (last) = switch_thread (&prev->thread, &next->thread); \ } \ } while (0) /* Enable/disable interrupts. */ #define local_irq_enable() __asm__ __volatile__ ("ei") #define local_irq_disable() __asm__ __volatile__ ("di") #define local_save_flags(flags) \ __asm__ __volatile__ ("stsr %1, %0" : "=r" (flags) : "i" (SR_PSW)) #define local_restore_flags(flags) \ __asm__ __volatile__ ("ldsr %0, %1" :: "r" (flags), "i" (SR_PSW)) /* For spinlocks etc */ #define local_irq_save(flags) \ do { local_save_flags (flags); local_irq_disable (); } while (0) #define local_irq_restore(flags) \ local_restore_flags (flags); static inline int irqs_disabled (void) { unsigned flags; local_save_flags (flags); return !!(flags & 0x20); } /* * Force strict CPU ordering. * Not really required on v850... */ #define nop() __asm__ __volatile__ ("nop") #define mb() __asm__ __volatile__ ("" ::: "memory") #define rmb() mb () #define wmb() mb () #define read_barrier_depends() ((void)0) #define set_rmb(var, value) do { xchg (&var, value); } while (0) #define set_mb(var, value) set_rmb (var, value) #define smp_mb() mb () #define smp_rmb() rmb () #define smp_wmb() wmb () #define smp_read_barrier_depends() read_barrier_depends() #define xchg(ptr, with) \ ((__typeof__ (*(ptr)))__xchg ((unsigned long)(with), (ptr), sizeof (*(ptr)))) #define tas(ptr) (xchg ((ptr), 1)) static inline unsigned long __xchg (unsigned long with, __volatile__ void *ptr, int size) { unsigned long tmp, flags; local_irq_save (flags); switch (size) { case 1: tmp = *(unsigned char *)ptr; *(unsigned char *)ptr = with; break; case 2: tmp = *(unsigned short *)ptr; *(unsigned short *)ptr = with; break; case 4: tmp = *(unsigned long *)ptr; *(unsigned long *)ptr = with; break; } local_irq_restore (flags); return tmp; } #define arch_align_stack(x) (x) #endif /* __V850_SYSTEM_H__ */