#ifndef _H8300_SYSTEM_H #define _H8300_SYSTEM_H #include <linux/linkage.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. This * also clears the TS-flag if the task we switched to has used the * math co-processor latest. */ /* * switch_to() saves the extra registers, that are not saved * automatically by SAVE_SWITCH_STACK in resume(), ie. d0-d5 and * a0-a1. Some of these are used by schedule() and its predecessors * and so we might get see unexpected behaviors when a task returns * with unexpected register values. * * syscall stores these registers itself and none of them are used * by syscall after the function in the syscall has been called. * * Beware that resume now expects *next to be in d1 and the offset of * tss to be in a1. This saves a few instructions as we no longer have * to push them onto the stack and read them back right after. * * 02/17/96 - Jes Sorensen (jds@kom.auc.dk) * * Changed 96/09/19 by Andreas Schwab * pass prev in a0, next in a1, offset of tss in d1, and whether * the mm structures are shared in d2 (to avoid atc flushing). * * H8/300 Porting 2002/09/04 Yoshinori Sato */ asmlinkage void resume(void); #define switch_to(prev,next,last) { \ void *_last; \ __asm__ __volatile__( \ "mov.l %1, er0\n\t" \ "mov.l %2, er1\n\t" \ "mov.l %3, er2\n\t" \ "jsr @_resume\n\t" \ "mov.l er2,%0\n\t" \ : "=r" (_last) \ : "r" (&(prev->thread)), \ "r" (&(next->thread)), \ "g" (prev) \ : "cc", "er0", "er1", "er2", "er3"); \ (last) = _last; \ } #define __sti() asm volatile ("andc #0x7f,ccr") #define __cli() asm volatile ("orc #0x80,ccr") #define __save_flags(x) \ asm volatile ("stc ccr,%w0":"=r" (x)) #define __restore_flags(x) \ asm volatile ("ldc %w0,ccr": :"r" (x)) #define irqs_disabled() \ ({ \ unsigned char flags; \ __save_flags(flags); \ ((flags & 0x80) == 0x80); \ }) #define iret() __asm__ __volatile__ ("rte": : :"memory", "sp", "cc") /* For spinlocks etc */ #define local_irq_disable() __cli() #define local_irq_enable() __sti() #define local_irq_save(x) ({ __save_flags(x); local_irq_disable(); }) #define local_irq_restore(x) __restore_flags(x) #define local_save_flags(x) __save_flags(x) /* * Force strict CPU ordering. * Not really required on H8... */ #define nop() asm volatile ("nop"::) #define mb() asm volatile ("" : : :"memory") #define rmb() asm volatile ("" : : :"memory") #define wmb() asm volatile ("" : : :"memory") #define set_mb(var, value) do { xchg(&var, value); } while (0) #ifdef CONFIG_SMP #define smp_mb() mb() #define smp_rmb() rmb() #define smp_wmb() wmb() #define smp_read_barrier_depends() read_barrier_depends() #else #define smp_mb() barrier() #define smp_rmb() barrier() #define smp_wmb() barrier() #define smp_read_barrier_depends() do { } while(0) #endif #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr)))) struct __xchg_dummy { unsigned long a[100]; }; #define __xg(x) ((volatile struct __xchg_dummy *)(x)) static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) { unsigned long tmp, flags; local_irq_save(flags); switch (size) { case 1: __asm__ __volatile__ ("mov.b %2,%0\n\t" "mov.b %1,%2" : "=&r" (tmp) : "r" (x), "m" (*__xg(ptr)) : "memory"); break; case 2: __asm__ __volatile__ ("mov.w %2,%0\n\t" "mov.w %1,%2" : "=&r" (tmp) : "r" (x), "m" (*__xg(ptr)) : "memory"); break; case 4: __asm__ __volatile__ ("mov.l %2,%0\n\t" "mov.l %1,%2" : "=&r" (tmp) : "r" (x), "m" (*__xg(ptr)) : "memory"); break; default: tmp = 0; } local_irq_restore(flags); return tmp; } #define HARD_RESET_NOW() ({ \ local_irq_disable(); \ asm("jmp @@0"); \ }) #include <asm-generic/cmpxchg-local.h> /* * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make * them available. */ #define cmpxchg_local(ptr, o, n) \ ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\ (unsigned long)(n), sizeof(*(ptr)))) #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) #ifndef CONFIG_SMP #include <asm-generic/cmpxchg.h> #endif #define arch_align_stack(x) (x) #endif /* _H8300_SYSTEM_H */