1. 根目录:
2. arch
3. microblaze
4. include
5. asm
6. system.h

/*
 * Copyright (C) 2006 Atmark Techno, Inc.
 *
 * 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.
 */

#ifndef _ASM_MICROBLAZE_SYSTEM_H
#define _ASM_MICROBLAZE_SYSTEM_H

#include <asm/registers.h>
#include <asm/setup.h>
#include <asm/irqflags.h>
#include <asm/cache.h>

#include <asm-generic/cmpxchg.h>
#include <asm-generic/cmpxchg-local.h>

#define __ARCH_WANT_INTERRUPTS_ON_CTXSW

struct task_struct;
struct thread_info;

extern struct task_struct *_switch_to(struct thread_info *prev,
					struct thread_info *next);

#define switch_to(prev, next, last)					\
	do {								\
		(last) = _switch_to(task_thread_info(prev),		\
					task_thread_info(next));	\
	} while (0)

#define smp_read_barrier_depends()	do {} while (0)
#define read_barrier_depends()		do {} while (0)

#define nop()			asm volatile ("nop")
#define mb()			barrier()
#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)

#define smp_mb()		mb()
#define smp_rmb()		rmb()
#define smp_wmb()		wmb()

void __bad_xchg(volatile void *ptr, int size);

static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
								int size)
{
	unsigned long ret;
	unsigned long flags;

	switch (size) {
	case 1:
		local_irq_save(flags);
		ret = *(volatile unsigned char *)ptr;
		*(volatile unsigned char *)ptr = x;
		local_irq_restore(flags);
		break;

	case 4:
		local_irq_save(flags);
		ret = *(volatile unsigned long *)ptr;
		*(volatile unsigned long *)ptr = x;
		local_irq_restore(flags);
		break;
	default:
		__bad_xchg(ptr, size), ret = 0;
		break;
	}

	return ret;
}

void disable_hlt(void);
void enable_hlt(void);
void default_idle(void);

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

void free_init_pages(char *what, unsigned long begin, unsigned long end);
void free_initmem(void);
extern char *klimit;
extern void ret_from_fork(void);

extern void *alloc_maybe_bootmem(size_t size, gfp_t mask);
extern void *zalloc_maybe_bootmem(size_t size, gfp_t mask);

#ifdef CONFIG_DEBUG_FS
extern struct dentry *of_debugfs_root;
#endif

#define arch_align_stack(x) (x)

/*
 * MicroBlaze doesn't handle unaligned accesses in hardware.
 *
 * Based on this we force the IP header alignment in network drivers.
 */
#define NET_IP_ALIGN	2

#endif /* _ASM_MICROBLAZE_SYSTEM_H */