pcibios.c

MIPS处理器的bootloader,龙芯就是用的修改过的PMON2

/*	$Id: pcibios.c,v 1.2 2003/05/21 10:17:24 pefo Exp $ */

/*
 * Copyright (c) 2002 Opsycon AB  (www.opsycon.se)
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by Opsycon AB, Sweden.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */

#include <stdio.h>
#include <dev/pci/pcivar.h>
#include "pcibios.h"

int
pcibios_find_pci_device (
	u_int16_t VendorID,
	u_int16_t DeviceID,
	u_int16_t Index,
	u_int8_t *bus,
	u_int8_t *device_fn)
{
	u_int16_t vendid, devid;
	u_int8_t Bus, device;

	if (VendorID == 0xffff)
		return PCIBIOS_BAD_VENDOR_ID;

	for (Bus = 0; Bus <= 255; Bus++)
	{
		for (device = 0; device <= 31; device++)
		{
			/* If no device there, we'll hit the continue */
			if ((pcibios_read_config_word (Bus, device<<3, 0x0, &vendid)
				!= PCIBIOS_SUCCESSFUL) || (vendid != VendorID))
			    continue;

			if ((pcibios_read_config_word (Bus, device<<3, 0x2, &devid)
				!= PCIBIOS_SUCCESSFUL) || (devid != DeviceID))
			    continue;

			/* If we've gotten this far we've found a match */
			if (Index-- != 0)
				continue;

			*bus = Bus;
			*device_fn = device<<3;
			return PCIBIOS_SUCCESSFUL;
		}
	}

	/* If we haven't returned by this point, no match was found */
	return PCIBIOS_DEVICE_NOT_FOUND;
}

int
pcibios_find_pci_class_code (
	u_int32_t ClassCode,
	u_int16_t Index,
	u_int8_t *bus,
	u_int8_t *device_fn)
{
    u_int16_t vendid;
    u_int8_t Bus, device;
    u_int8_t dev_class;

    for (Bus = 0; Bus <= 255; Bus++)
    {
        for (device = 0; device <= 31; device++)
        {
            /* If no device there, we'll hit the continue */
            if ((pcibios_read_config_word (Bus, device<<3, 0x0, &vendid)
				!= PCIBIOS_SUCCESSFUL) || (vendid == 0xffff) ||
                (pcibios_read_config_byte (Bus, device<<3, 0xb, &dev_class)
				!= PCIBIOS_SUCCESSFUL) || (dev_class != ClassCode))
				continue;

            /* If we've gotten this far we've found a match */
            if (Index-- != 0)
				continue;

            *bus = Bus;
            *device_fn = device<<3;
			return PCIBIOS_SUCCESSFUL;
        }
    }  

    /* If we haven't returned by this point, no match was found */
    return PCIBIOS_DEVICE_NOT_FOUND;
}

int
pcibios_read_config_byte (
	u_int8_t bus,
	u_int8_t device_fn,
	u_int8_t where,
	u_int8_t *value)
{
	u_int32_t tag;

	tag = (bus << 16) + (device_fn << 8);

	*value = (u_int8_t)
		((_pci_conf_read(tag, where & ~0x3) >> ((where % 0x4) * 8)) & 0xff);

	return PCIBIOS_SUCCESSFUL;
}

int
pcibios_read_config_word (
	u_int8_t bus,
	u_int8_t device_fn,
	u_int8_t where,
	u_int16_t *value)
{
	u_int32_t tag;

	if (where & 0x01)
		return PCIBIOS_BAD_REGISTER_NUMBER;

	tag = (bus << 16) + (device_fn << 8);

	*value = (u_int16_t)
		((_pci_conf_read(tag, where & ~0x3) >> ((where % 0x4) * 8)) & 0xffff);

	return PCIBIOS_SUCCESSFUL;
}

int
pcibios_read_config_dword (
	u_int8_t bus,
	u_int8_t device_fn,
	u_int8_t where,
	u_int32_t *value)
{
	u_int32_t tag;

	if (where & 0x03)
		return PCIBIOS_BAD_REGISTER_NUMBER;

	tag = (bus << 16) + (device_fn << 8);

	*value = _pci_conf_read(tag, where);

	return PCIBIOS_SUCCESSFUL;
}

int
pcibios_write_config_byte (
	u_int8_t bus,
	u_int8_t device_fn,
	u_int8_t where,
	u_int8_t value)
{
	u_int32_t tag, old_value;

	tag = (bus << 16) + (device_fn << 8);

	/* get original value */
	old_value = _pci_conf_read(tag, where & ~0x3);

	/* mask out the desired byte */
	old_value &= (~(0x000000ff << ((where % 0x4) * 8)));

	/* or in the new byte */
	old_value |= (((u_int32_t)value) << ((where % 4) * 8));

	_pci_conf_write(tag, where & ~0x3, old_value);

	return PCIBIOS_SUCCESSFUL;
}

int
pcibios_write_config_word (
	u_int8_t bus,
	u_int8_t device_fn,
	u_int8_t where,
	u_int16_t value)
{
	u_int32_t tag, old_value;

	if (where & 0x01)
		return PCIBIOS_BAD_REGISTER_NUMBER;

	tag = (bus << 16) + (device_fn << 8);

	/* get original value */
	old_value = _pci_conf_read(tag, where & ~0x3);

	/* mask out the desired word */
	old_value &= (~(0x0000ffff << ((where % 0x2) * 8)));

	/* or in the new word */
	old_value |= (((u_int32_t)value) << ((where % 4) * 8));

	_pci_conf_write(tag, where & ~0x3, old_value);

	return PCIBIOS_SUCCESSFUL;
}

int
pcibios_write_config_dword (
	u_int8_t bus,
	u_int8_t device_fn,
	u_int8_t where,
	u_int32_t value)
{
	u_int32_t tag;

	if (where & 0x03)
		return PCIBIOS_BAD_REGISTER_NUMBER;

	tag = (bus << 16) + (device_fn << 8);

	_pci_conf_write(tag, where, value);

	return PCIBIOS_SUCCESSFUL;
}