io.h

来自「linux 内核源代码」· C头文件 代码 · 共 55 行

/*
 *  include/asm-s390/io.h
 *
 *  S390 version
 *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
 *    Author(s): Martin Schwidefsky ([e-mail])
 *
 *  Derived from "include/asm-i386/io.h"
 */

#ifndef _S390_IO_H
#define _S390_IO_H

#ifdef __KERNEL__

#include <asm/page.h>

#define IO_SPACE_LIMIT 0xffffffff

/*
 * Change virtual addresses to physical addresses and vv.
 * These are pretty trivial
 */
static inline unsigned long virt_to_phys(volatile void * address)
{
	unsigned long real_address;
	asm volatile(
		 "	lra	%0,0(%1)\n"
		 "	jz	0f\n"
		 "	la	%0,0\n"
                 "0:"
		 : "=a" (real_address) : "a" (address) : "cc");
        return real_address;
}

static inline void * phys_to_virt(unsigned long address)
{
	return (void *) address;
}

/*
 * Convert a physical pointer to a virtual kernel pointer for /dev/mem
 * access
 */
#define xlate_dev_mem_ptr(p)	__va(p)

/*
 * Convert a virtual cached pointer to an uncached pointer
 */
#define xlate_dev_kmem_ptr(p)	p

#endif /* __KERNEL__ */

#endif