1. 根目录:
2. arch
3. m68k
4. include
5. asm
6. io_no.h

#ifndef _M68KNOMMU_IO_H
#define _M68KNOMMU_IO_H

#ifdef __KERNEL__

#include <asm/virtconvert.h>
#include <asm-generic/iomap.h>

/*
 * These are for ISA/PCI shared memory _only_ and should never be used
 * on any other type of memory, including Zorro memory. They are meant to
 * access the bus in the bus byte order which is little-endian!.
 *
 * readX/writeX() are used to access memory mapped devices. On some
 * architectures the memory mapped IO stuff needs to be accessed
 * differently. On the m68k architecture, we just read/write the
 * memory location directly.
 */
/* ++roman: The assignments to temp. vars avoid that gcc sometimes generates
 * two accesses to memory, which may be undesirable for some devices.
 */

/*
 * swap functions are sometimes needed to interface little-endian hardware
 */
static inline unsigned short _swapw(volatile unsigned short v)
{
    return ((v << 8) | (v >> 8));
}

static inline unsigned int _swapl(volatile unsigned long v)
{
    return ((v << 24) | ((v & 0xff00) << 8) | ((v & 0xff0000) >> 8) | (v >> 24));
}

#define readb(addr) \
    ({ unsigned char __v = (*(volatile unsigned char *) (addr)); __v; })
#define readw(addr) \
    ({ unsigned short __v = (*(volatile unsigned short *) (addr)); __v; })
#define readl(addr) \
    ({ unsigned int __v = (*(volatile unsigned int *) (addr)); __v; })

#define writeb(b,addr) (void)((*(volatile unsigned char *) (addr)) = (b))
#define writew(b,addr) (void)((*(volatile unsigned short *) (addr)) = (b))
#define writel(b,addr) (void)((*(volatile unsigned int *) (addr)) = (b))

#define __raw_readb readb
#define __raw_readw readw
#define __raw_readl readl
#define __raw_writeb writeb
#define __raw_writew writew
#define __raw_writel writel

static inline void io_outsb(unsigned int addr, const void *buf, int len)
{
	volatile unsigned char *ap = (volatile unsigned char *) addr;
	unsigned char *bp = (unsigned char *) buf;
	while (len--)
		*ap = *bp++;
}

static inline void io_outsw(unsigned int addr, const void *buf, int len)
{
	volatile unsigned short *ap = (volatile unsigned short *) addr;
	unsigned short *bp = (unsigned short *) buf;
	while (len--)
		*ap = _swapw(*bp++);
}

static inline void io_outsl(unsigned int addr, const void *buf, int len)
{
	volatile unsigned int *ap = (volatile unsigned int *) addr;
	unsigned int *bp = (unsigned int *) buf;
	while (len--)
		*ap = _swapl(*bp++);
}

static inline void io_insb(unsigned int addr, void *buf, int len)
{
	volatile unsigned char *ap = (volatile unsigned char *) addr;
	unsigned char *bp = (unsigned char *) buf;
	while (len--)
		*bp++ = *ap;
}

static inline void io_insw(unsigned int addr, void *buf, int len)
{
	volatile unsigned short *ap = (volatile unsigned short *) addr;
	unsigned short *bp = (unsigned short *) buf;
	while (len--)
		*bp++ = _swapw(*ap);
}

static inline void io_insl(unsigned int addr, void *buf, int len)
{
	volatile unsigned int *ap = (volatile unsigned int *) addr;
	unsigned int *bp = (unsigned int *) buf;
	while (len--)
		*bp++ = _swapl(*ap);
}

#define mmiowb()

/*
 *	make the short names macros so specific devices
 *	can override them as required
 */

#define memset_io(a,b,c)	memset((void *)(a),(b),(c))
#define memcpy_fromio(a,b,c)	memcpy((a),(void *)(b),(c))
#define memcpy_toio(a,b,c)	memcpy((void *)(a),(b),(c))

#define inb(addr)    readb(addr)
#define inw(addr)    readw(addr)
#define inl(addr)    readl(addr)
#define outb(x,addr) ((void) writeb(x,addr))
#define outw(x,addr) ((void) writew(x,addr))
#define outl(x,addr) ((void) writel(x,addr))

#define inb_p(addr)    inb(addr)
#define inw_p(addr)    inw(addr)
#define inl_p(addr)    inl(addr)
#define outb_p(x,addr) outb(x,addr)
#define outw_p(x,addr) outw(x,addr)
#define outl_p(x,addr) outl(x,addr)

#define outsb(a,b,l) io_outsb(a,b,l)
#define outsw(a,b,l) io_outsw(a,b,l)
#define outsl(a,b,l) io_outsl(a,b,l)

#define insb(a,b,l) io_insb(a,b,l)
#define insw(a,b,l) io_insw(a,b,l)
#define insl(a,b,l) io_insl(a,b,l)

#define IO_SPACE_LIMIT 0xffffffff


/* Values for nocacheflag and cmode */
#define IOMAP_FULL_CACHING		0
#define IOMAP_NOCACHE_SER		1
#define IOMAP_NOCACHE_NONSER		2
#define IOMAP_WRITETHROUGH		3

static inline void *__ioremap(unsigned long physaddr, unsigned long size, int cacheflag)
{
	return (void *) physaddr;
}
static inline void *ioremap(unsigned long physaddr, unsigned long size)
{
	return __ioremap(physaddr, size, IOMAP_NOCACHE_SER);
}
static inline void *ioremap_nocache(unsigned long physaddr, unsigned long size)
{
	return __ioremap(physaddr, size, IOMAP_NOCACHE_SER);
}
static inline void *ioremap_writethrough(unsigned long physaddr, unsigned long size)
{
	return __ioremap(physaddr, size, IOMAP_WRITETHROUGH);
}
static inline void *ioremap_fullcache(unsigned long physaddr, unsigned long size)
{
	return __ioremap(physaddr, size, IOMAP_FULL_CACHING);
}

#define	iounmap(addr)	do { } while(0)

/*
 * 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

static inline void __iomem *ioport_map(unsigned long port, unsigned int nr)
{
	return (void __iomem *) port;
}

static inline void ioport_unmap(void __iomem *p)
{
}

#endif /* __KERNEL__ */

#endif /* _M68KNOMMU_IO_H */