linux/include/asm-sh/system.h

#ifndef __ASM_SH_SYSTEM_H
#define __ASM_SH_SYSTEM_H

/*
 * Copyright (C) 1999, 2000  Niibe Yutaka  &  Kaz Kojima
 * Copyright (C) 2002 Paul Mundt
 */

#include <linux/irqflags.h>
#include <linux/compiler.h>
#include <linux/linkage.h>
#include <asm/types.h>
#include <asm/ptrace.h>

#define AT_VECTOR_SIZE_ARCH 1 /* entries in ARCH_DLINFO */

#if defined(CONFIG_CPU_SH4A) || defined(CONFIG_CPU_SH5)
#define __icbi()			\
{					\
	unsigned long __addr;		\
	__addr = 0xa8000000;		\
	__asm__ __volatile__(		\
		"icbi   %0\n\t"		\
		: /* no output */	\
		: "m" (__m(__addr)));	\
}
#endif

/*
 * A brief note on ctrl_barrier(), the control register write barrier.
 *
 * Legacy SH cores typically require a sequence of 8 nops after
 * modification of a control register in order for the changes to take
 * effect. On newer cores (like the sh4a and sh5) this is accomplished
 * with icbi.
 *
 * Also note that on sh4a in the icbi case we can forego a synco for the
 * write barrier, as it's not necessary for control registers.
 *
 * Historically we have only done this type of barrier for the MMUCR, but
 * it's also necessary for the CCR, so we make it generic here instead.
 */
#if defined(CONFIG_CPU_SH4A) || defined(CONFIG_CPU_SH5)
#define mb()		__asm__ __volatile__ ("synco": : :"memory")
#define rmb()		mb()
#define wmb()		__asm__ __volatile__ ("synco": : :"memory")
#define ctrl_barrier()	__icbi()
#define read_barrier_depends()	do { } while(0)
#else
#define mb()		__asm__ __volatile__ ("": : :"memory")
#define rmb()		mb()
#define wmb()		__asm__ __volatile__ ("": : :"memory")
#define ctrl_barrier()	__asm__ __volatile__ ("nop;nop;nop;nop;nop;nop;nop;nop")
#define read_barrier_depends()	do { } while(0)
#endif

#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 set_mb(var, value) do { (void)xchg(&var, value); } while (0)

static inline unsigned long xchg_u32(volatile u32 *m, unsigned long val)
{
	unsigned long flags, retval;

	local_irq_save(flags);
	retval = *m;
	*m = val;
	local_irq_restore(flags);
	return retval;
}

static inline unsigned long xchg_u8(volatile u8 *m, unsigned long val)
{
	unsigned long flags, retval;

	local_irq_save(flags);
	retval = *m;
	*m = val & 0xff;
	local_irq_restore(flags);
	return retval;
}

extern void __xchg_called_with_bad_pointer(void);

#define __xchg(ptr, x, size)				\
({							\
	unsigned long __xchg__res;			\
	volatile void *__xchg_ptr = (ptr);		\
	switch (size) {					\
	case 4:						\
		__xchg__res = xchg_u32(__xchg_ptr, x);	\
		break;					\
	case 1:						\
		__xchg__res = xchg_u8(__xchg_ptr, x);	\
		break;					\
	default:					\
		__xchg_called_with_bad_pointer();	\
		__xchg__res = x;			\
		break;					\
	}						\
							\
	__xchg__res;					\
})

#define xchg(ptr,x)	\
	((__typeof__(*(ptr)))__xchg((ptr),(unsigned long)(x), sizeof(*(ptr))))

static inline unsigned long __cmpxchg_u32(volatile int * m, unsigned long old,
	unsigned long new)
{
	__u32 retval;
	unsigned long flags;

	local_irq_save(flags);
	retval = *m;
	if (retval == old)
		*m = new;
	local_irq_restore(flags);       /* implies memory barrier  */
	return retval;
}

/* This function doesn't exist, so you'll get a linker error
 * if something tries to do an invalid cmpxchg(). */
extern void __cmpxchg_called_with_bad_pointer(void);

#define __HAVE_ARCH_CMPXCHG 1

static inline unsigned long __cmpxchg(volatile void * ptr, unsigned long old,
		unsigned long new, int size)
{
	switch (size) {
	case 4:
		return __cmpxchg_u32(ptr, old, new);
	}
	__cmpxchg_called_with_bad_pointer();
	return old;
}

#define cmpxchg(ptr,o,n)						 \
  ({									 \
     __typeof__(*(ptr)) _o_ = (o);					 \
     __typeof__(*(ptr)) _n_ = (n);					 \
     (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,		 \
				    (unsigned long)_n_, sizeof(*(ptr))); \
  })

extern void die(const char *str, struct pt_regs *regs, long err) __attribute__ ((noreturn));

extern void *set_exception_table_vec(unsigned int vec, void *handler);

static inline void *set_exception_table_evt(unsigned int evt, void *handler)
{
	return set_exception_table_vec(evt >> 5, handler);
}

/*
 * SH-2A has both 16 and 32-bit opcodes, do lame encoding checks.
 */
#ifdef CONFIG_CPU_SH2A
extern unsigned int instruction_size(unsigned int insn);
#elif defined(CONFIG_SUPERH32)
#define instruction_size(insn)	(2)
#else
#define instruction_size(insn)	(4)
#endif

/* XXX
 * disable hlt during certain critical i/o operations
 */
#define HAVE_DISABLE_HLT
void disable_hlt(void);
void enable_hlt(void);

void default_idle(void);
void per_cpu_trap_init(void);

asmlinkage void break_point_trap(void);

#ifdef CONFIG_SUPERH32
#define BUILD_TRAP_HANDLER(name)					\
asmlinkage void name##_trap_handler(unsigned long r4, unsigned long r5,	\
				    unsigned long r6, unsigned long r7,	\
				    struct pt_regs __regs)

#define TRAP_HANDLER_DECL				\
	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);	\
	unsigned int vec = regs->tra;
#else
#define BUILD_TRAP_HANDLER(name)	\
asmlinkage void name##_trap_handler(unsigned int vec, struct pt_regs *regs)
#define TRAP_HANDLER_DECL
#endif

BUILD_TRAP_HANDLER(address_error);
BUILD_TRAP_HANDLER(debug);
BUILD_TRAP_HANDLER(bug);

#define arch_align_stack(x) (x)

#ifdef CONFIG_SUPERH32
# include "system_32.h"
#else
# include "system_64.h"
#endif

#endif