/* * include/asm-microblaze/system.h -- Low-level interrupt/thread ops * * Copyright (C) 2003 John Williams (jwilliams@itee.uq.edu.au) * based upon microblaze version * Copyright (C) 2001 NEC Corporation * Copyright (C) 2001 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> * Microblaze port by John Williams * Microblaze port by John Williams */ #ifndef __MICROBLAZE_SYSTEM_H__ #define __MICROBLAZE_SYSTEM_H__ #if 0 #include <linux/linkage.h> #endif #include <asm/ptrace.h> #define prepare_to_switch() do { } while (0) /* * 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 __sti() \ { \ register unsigned tmp; \ __asm__ __volatile__ (" \ mfs %0, rmsr; \ ori %0, %0, 2; \ mts rmsr, %0" \ : "=r" (tmp) \ : \ : "memory"); \ } #define __cli() \ { \ register unsigned tmp; \ __asm__ __volatile__ (" \ mfs %0, rmsr; \ andi %0, %0, ~2; \ mts rmsr, %0" \ : "=r" (tmp) \ : \ : "memory"); \ } #define __save_flags(flags) \ __asm__ __volatile__ ("mfs %0, rmsr" : "=r" (flags)) #define __restore_flags(flags) \ __asm__ __volatile__ ("mts rmsr, %0" :: "r" (flags)) #define __save_flags_cli(flags) \ { \ register unsigned tmp; \ __asm__ __volatile__ (" \ mfs %0, rmsr; \ andi %1, %0, ~2; \ mts rmsr, %1;" \ : "=r" (flags), "=r" (tmp) \ : \ : "memory"); \ } #define __save_flags_sti(flags) \ { \ register unsigned tmp; \ __asm__ __volatile__ (" \ mfs %0, rmsr; \ ori %1, %0, 2; \ mts rmsr, %1;" \ : "=r" (flags) ,"=r" (tmp) \ : \ : "memory"); \ } /* For spinlocks etc */ #define local_irq_save(flags) __save_flags_cli (flags) #define local_irq_set(flags) __save_flags_sti (flags) #define local_irq_restore(flags) __restore_flags (flags) #define local_irq_disable() __cli () #define local_irq_enable() __sti () #define cli() __cli () #define sti() __sti () #define save_flags(flags) __save_flags (flags) #define restore_flags(flags) __restore_flags (flags) #define save_flags_cli(flags) __save_flags_cli (flags) /* * Force strict CPU ordering. * Not really required on microblaze... */ #define nop() __asm__ __volatile__ ("nop") #define mb() __asm__ __volatile__ ("nop" ::: "memory") #define rmb() mb () #define wmb() mb () #define set_mb(var, value) do { var = value; mb(); } while (0) #define set_wmb(var, value) do { var = value; wmb (); } while (0) #ifdef CONFIG_SMP #define smp_mb() mb () #define smp_rmb() rmb () #define smp_wmb() wmb () #else #define smp_mb() barrier () #define smp_rmb() barrier () #define smp_wmb() barrier () #endif #define xchg(ptr, with) \ ((__typeof__ (*(ptr)))__xchg ((unsigned long)(with), (ptr), sizeof (*(ptr)))) #define tas(ptr) (xchg ((ptr), 1)) extern inline unsigned long __xchg (unsigned long with, __volatile__ void *ptr, int size) { unsigned long tmp, flags; save_flags_cli (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; } restore_flags (flags); return tmp; } #endif /* __MICROBLAZE_SYSTEM_H__ */