io.h

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/*
 *  arch/arm/mach-rpc/include/mach/io.h
 *
 *  Copyright (C) 1997 Russell King
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Modifications:
 *  06-Dec-1997 RMK Created.
 */
#ifndef __ASM_ARM_ARCH_IO_H
#define __ASM_ARM_ARCH_IO_H

#include <mach/hardware.h>

#define IO_SPACE_LIMIT 0xffff

/*
 * We need PC style IO addressing for:
 *  - floppy (at 0x3f2,0x3f4,0x3f5,0x3f7)
 *  - parport (at 0x278-0x27a, 0x27b-0x27f, 0x778-0x77a)
 *  - 8250 serial (only for compile)
 *
 * These peripherals are found in an area of MMIO which looks very much
 * like an ISA bus, but with registers at the low byte of each word.
 */
#define __io(a)     (PCIO_BASE + ((a) << 2))

#endif