#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"); \
})
#define arch_align_stack(x) (x)
#endif /* _H8300_SYSTEM_H */
