src/northbridge/intel/sch/acpi.c

/*
 * This file is part of the coreboot project.
 *
 * Copyright (C) 2007-2009 coresystems GmbH
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <types.h>
#include <string.h>
#include <console/console.h>
#include <arch/acpi.h>
#include <arch/acpigen.h>
#include <device/device.h>
#include <device/pci.h>
#include <device/pci_ids.h>

unsigned long acpi_fill_mcfg(unsigned long current)
{
	device_t dev;
	u32 pciexbar = 0;
	u32 pciexbar_reg;
	int max_buses;

	dev = dev_find_device(0x8086, 0x27a0, 0);
	if (!dev)
		return current;

	pciexbar_reg = pci_read_config32(dev, 0x48);

	/* MMCFG not supported or not enabled. */
	if (!(pciexbar_reg & (1 << 0)))
		return current;

	switch ((pciexbar_reg >> 1) & 3) {
	case 0: /* 256MB */
		pciexbar = pciexbar_reg & ((1 << 31) | (1 << 30) | (1 << 29) |
					   (1 << 28));
		max_buses = 256;
		break;
	case 1: /* 128M */
		pciexbar = pciexbar_reg & ((1 << 31) | (1 << 30) | (1 << 29) |
					   (1 << 28) | (1 << 27));
		max_buses = 128;
		break;
	case 2: /* 64M */
		pciexbar = pciexbar_reg & ((1 << 31) | (1 << 30) | (1 << 29) |
					   (1 << 28) | (1 << 27) | (1 << 26));
		max_buses = 64;
		break;
	default: /* RSVD */
		return current;
	}

	if (!pciexbar)
		return current;

#if CONFIG_GENERATE_ACPI_TABLES
	current += acpi_create_mcfg_mmconfig((acpi_mcfg_mmconfig_t *) current,
					     pciexbar, 0x0, 0x0, max_buses - 1);
#endif
	return current;
}