linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * Implement the default iomap interfaces

 *

 * (C) Copyright 2004 Linus Torvalds

 */

#include <linux/pci.h>

#include <linux/io.h>

​

#include <linux/export.h>

​

/*

 * Read/write from/to an (offsettable) iomem cookie. It might be a PIO

 * access or a MMIO access, these functions don't care. The info is

 * encoded in the hardware mapping set up by the mapping functions

 * (or the cookie itself, depending on implementation and hw).

 *

 * The generic routines don't assume any hardware mappings, and just

 * encode the PIO/MMIO as part of the cookie. They coldly assume that

 * the MMIO IO mappings are not in the low address range.

 *

 * Architectures for which this is not true can't use this generic

 * implementation and should do their own copy.

 */

​

#ifndef HAVE_ARCH_PIO_SIZE

/*

 * We encode the physical PIO addresses (0-0xffff) into the

 * pointer by offsetting them with a constant (0x10000) and

 * assuming that all the low addresses are always PIO. That means

 * we can do some sanity checks on the low bits, and don't

 * need to just take things for granted.

 */

#define PIO_OFFSET  0x10000UL

#define PIO_MASK    0x0ffffUL

#define PIO_RESERVED    0x40000UL

#endif

​

static void bad_io_access(unsigned long port, const char *access)

{

    static int count = 10;

    if (count) {

        count--;

        WARN(1, KERN_ERR "Bad IO access at port %#lx (%s)\n", port, access);

    }

}

​

/*

 * Ugly macros are a way of life.

 */

#define IO_COND(addr, is_pio, is_mmio) do {         \

    unsigned long port = (unsigned long __force)addr;   \

    if (port >= PIO_RESERVED) {             \

        is_mmio;                    \

    } else if (port > PIO_OFFSET) {             \

        port &= PIO_MASK;               \

        is_pio;                     \

    } else                          \

        bad_io_access(port, #is_pio );          \

} while (0)

​

#ifndef pio_read16be

#define pio_read16be(port) swab16(inw(port))