src/northbridge/intel/pineview/ram_calc.c

/*
 * This file is part of the coreboot project.
 *
 * Copyright (C) 2007-2009 coresystems GmbH
 * Copyright (C) 2015  Damien Zammit <damien@zamaudio.com>
 *
 * 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.
 */

#define __SIMPLE_DEVICE__

#include <arch/io.h>
#include <device/device.h>
#include <device/pci_def.h>
#include <console/console.h>
#include <cbmem.h>
#include <northbridge/intel/pineview/pineview.h>

u8 decode_pciebar(u32 *const base, u32 *const len)
{
	*base = 0;
	*len = 0;
	const pci_devfn_t dev = PCI_DEV(0,0,0);
	u32 pciexbar = 0;
	u32 pciexbar_reg;
	u32 reg32;
	int max_buses;
	const struct {
		u16 num_buses;
		u32 addr_mask;
	} busmask[] = {
		{256, 0xf0000000},
		{128, 0xf8000000},
		{64,  0xfc000000},
		{0,   0},
	};

	if (!dev)
		return 0;

	pciexbar_reg = pci_read_config32(dev, PCIEXBAR);

	// MMCFG not supported or not enabled.
	if (!(pciexbar_reg & (1 << 0))) {
		printk(BIOS_WARNING, "WARNING: MMCONF not set\n");
		return 0;
	}

	reg32 = (pciexbar_reg >> 1) & 3;
	pciexbar = pciexbar_reg & busmask[reg32].addr_mask;
	max_buses = busmask[reg32].num_buses;

	if (!pciexbar) {
		printk(BIOS_WARNING, "WARNING: pciexbar invalid\n");
		return 0;
	}

	*base = pciexbar;
	*len = max_buses << 20;
	return 1;
}

/** Decodes used Graphics Mode Select (GMS) to kilobytes. */
u32 decode_igd_memory_size(const u32 gms)
{
	const u32 gmssize[] = {
		0, 1, 4, 8, 16, 32, 48, 64, 128, 256
	};

	if (gms > 9) {
		printk(BIOS_DEBUG, "Bad Graphics Mode Select (GMS) value.\n");
		return 0;
	}
	return gmssize[gms] << 10;
}

/** Decodes used Graphics Stolen Memory (GSM) to kilobytes. */
u32 decode_igd_gtt_size(const u32 gsm)
{
	const u8 gsmsize[] = {
		0, 1, 0, 0,
	};

	if (gsm > 3) {
		printk(BIOS_DEBUG, "Bad Graphics Stolen Memory (GSM) value.\n");
		return 0;
	}
	return (u32)(gsmsize[gsm] << 10);
}