io.h

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#ifndef _M68K_IO_H
#define _M68K_IO_H

#ifdef __KERNEL__

#include <linux/config.h>

#ifdef CONFIG_ATARI
#include <asm/atarihw.h>

#define SLOW_DOWN_IO	do { if (MACH_IS_ATARI) MFPDELAY(); } while (0)
#endif

#include <asm/virtconvert.h>

/*
 * These are for 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 undesireable for some devices.
 */
#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 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_p(addr) readb(addr)
#define inb(addr) readb(addr)

#define outb(x,addr) ((void) writeb(x,addr))
#define outb_p(x,addr) outb(x,addr)

#ifndef CONFIG_SUN3
#define IO_SPACE_LIMIT 0xffff
#else
#define IO_SPACE_LIMIT 0x0fffffff
#endif

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

extern void *__ioremap(unsigned long physaddr, unsigned long size, int cacheflag);
extern void __iounmap(void *addr, unsigned long size);

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

extern void iounmap(void *addr);

/* Nothing to do */

#define dma_cache_inv(_start,_size)		do { } while (0)
#define dma_cache_wback(_start,_size)		do { } while (0)
#define dma_cache_wback_inv(_start,_size)	do { } while (0)

#endif /* __KERNEL__ */

#endif /* _M68K_IO_H */