/*

 * (C) Copyright IBM Corporation 2007

 * All Rights Reserved.

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 * copy of this software and associated documentation files (the "Software"),

 * to deal in the Software without restriction, including without limitation

 * on the rights to use, copy, modify, merge, publish, distribute, sub

 * license, and/or sell copies of the Software, and to permit persons to whom

 * the Software is furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice (including the next

 * paragraph) shall be included in all copies or substantial portions of the

 * Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.  IN NO EVENT SHALL

 * IBM AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER

 * DEALINGS IN THE SOFTWARE.

 */

/**

 * \file linux_devmem.c

 * Access PCI subsystem using Linux's the old /dev/mem interface.

 *

 * \note

 * This is currently just a skeleton.  It only includes the /dev/mem based

 * function for reading the device ROM.

 *

 * \author Ian Romanick <idr@us.ibm.com>

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <stdlib.h>

#include <string.h>

#include <stdio.h>

#include <unistd.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <fcntl.h>

#include <sys/mman.h>

#include <dirent.h>

#include <errno.h>

#include "pciaccess.h"

#include "pciaccess_private.h"

#include "linux_devmem.h"

/**

 * Read a device's expansion ROM using /dev/mem.

 *

 * \note

 * This function could probably be used, as-is, on other platforms that have

 * a /dev/mem interface.

 *

 * \bugs

 * Before using the VGA special case code, this function should check that

 * VGA access are routed to the device.  Right?

 */

_pci_hidden int

pci_device_linux_devmem_read_rom(struct pci_device *dev, void *buffer)

{

    struct pci_device_private *priv = (struct pci_device_private *) dev;

    int fd;

    int err = 0;

    uint32_t rom_base_tmp;

    pciaddr_t rom_base;

    pciaddr_t rom_size;

    int PCI_ROM;

    /* Handle some special cases of legacy devices.

     */

    if (priv->base.rom_size == 0) {

	/* VGA ROMs are supposed to be at 0xC0000.

	 */

	if ((priv->base.device_class & 0x00ffff00) == 0x000030000) {

	    rom_base = 0x000C0000;

	    rom_size = 0x00010000;

	    PCI_ROM = 0;

	}

	else {

	    /* "Function not implemented."

	     */

	    return ENOSYS;

	}

    }

    else {

	rom_base = priv->rom_base;

	rom_size = priv->base.rom_size;

	PCI_ROM = 1;

    }

    /* Enable the device's ROM.

     */

    if (PCI_ROM) {

	err = pci_device_cfg_read_u32(& priv->base, & rom_base_tmp, 48);

	if (err) {

	    return err;

	}

	if ((rom_base_tmp & 0x000000001) == 0) {

	    err = pci_device_cfg_write_u32(& priv->base,

					   rom_base_tmp | 1, 48);

	    if (err) {

		return err;

	    }

	}

    }

    /* Read the portion of /dev/mem that corresponds to the device's ROM.

     */

    fd = open("/dev/mem", O_RDONLY, 0);

    if (fd < 0) {

	err = errno;

    }

    else {

	size_t bytes;

	for (bytes = 0; bytes < rom_size; /* empty */) {

	    const ssize_t got = pread(fd, buffer, rom_size - bytes,

				      rom_base + bytes);

	    if (got == -1) {

		err = errno;

		break;

	    }

	    bytes += got;

	}

	close(fd);

    }

    /* Disable the device's ROM.

     */

    if (PCI_ROM && ((rom_base_tmp & 0x000000001) == 0)) {

	const int tmp_err = pci_device_cfg_write_u32(& priv->base,

						     rom_base_tmp, 48);

	/* Prefer to return the first error that occurred.

	 */

	if (err == 0) {

	    err = tmp_err;

	}

    }

    return err;

}