blob: e76d4d25e92302372d48d09503a64df555377409 [file] [log] [blame]
/*
* This file is part of the coreboot project.
*
* Copyright (C) 2014 Google Inc.
* Copyright (C) 2015 Intel Corporation.
* Copyright (C) 2016 Intel Corporation.
*
* 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.
*/
#include <arch/io.h>
#include <soc/bootblock.h>
#include <soc/pci_devs.h>
#include <soc/systemagent.h>
void bootblock_systemagent_early_init(void)
{
uint32_t reg;
/*
* The "io" variant of the config access is explicitly used to
* setup the PCIEXBAR because CONFIG_MMCONF_SUPPORT is set to
* to true. That way all subsequent non-explicit config accesses use
* MCFG. This code also assumes that bootblock_northbridge_init() is
* the first thing called in the non-asm boot block code. The final
* assumption is that no assembly code is using the
* CONFIG_MMCONF_SUPPORT option to do PCI config acceses.
*
* The PCIEXBAR is assumed to live in the memory mapped IO space under
* 4GiB.
*/
reg = 0;
pci_io_write_config32(SA_DEV_ROOT, PCIEXBAR + 4, reg);
reg = CONFIG_MMCONF_BASE_ADDRESS | 4 | 1; /* 64MiB - 0-63 buses. */
pci_io_write_config32(SA_DEV_ROOT, PCIEXBAR, reg);
}