/*
 * 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.
 */

#include <console/console.h>
#include <arch/io.h>
#include <stdint.h>
#include <device/device.h>
#include <device/pci.h>
#include <device/pci_ids.h>
#include <stdlib.h>
#include <string.h>
#include <cbmem.h>
#include <cpu/cpu.h>
#include <arch/acpi.h>
#include "sch.h"

static int get_pcie_bar(u32 *base)
{
	device_t dev;
	u32 pciexbar_reg;

	dev = dev_find_slot(0, PCI_DEVFN(0, 0));
	if (!dev)
		return 0;

	/* FIXME: Determine at runtime. */
#ifdef POULSBO_PRE_B1
	pciexbar_reg = sch_port_access_read(0, 0, 4);
#else
	pciexbar_reg = sch_port_access_read(2, 9, 4);
#endif

	if (!(pciexbar_reg & (1 << 0)))
		return 0;

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

	return 0;
}

static void add_fixed_resources(struct device *dev, int index)
{
	struct resource *resource;

	printk(BIOS_DEBUG, "Adding CMC shadow area\n");
	resource = new_resource(dev, index++);
	resource->base = (resource_t) CMC_SHADOW;
	resource->size = (resource_t) (64 * 1024);
	resource->flags = IORESOURCE_MEM | IORESOURCE_RESERVE |
	    IORESOURCE_FIXED | IORESOURCE_STORED | IORESOURCE_ASSIGNED;
}

static void pci_domain_set_resources(device_t dev)
{
	u32 pci_tolm;
	u8 reg8;
	u16 reg16;
	unsigned long long tomk, tolud, tomk_stolen;
	uint64_t uma_memory_base = 0, uma_memory_size = 0;
	uint64_t tseg_memory_base = 0, tseg_memory_size = 0;

	/* Can we find out how much memory we can use at most this way? */
	pci_tolm = find_pci_tolm(dev->link_list);
	printk(BIOS_DEBUG, "pci_tolm: 0x%x\n", pci_tolm);
	printk(BIOS_SPEW, "Base of stolen memory: 0x%08x\n",
	       pci_read_config32(dev_find_slot(0, PCI_DEVFN(2, 0)), 0x5c));

	tolud = sch_port_access_read(2, 8, 4);
	printk(BIOS_SPEW, "Top of Low Used DRAM: 0x%08llx\n", tolud);

	tomk = tolud / 1024;
	tomk_stolen = tomk;

	/* Note: subtract IGD device and TSEG. */
	reg8 = pci_read_config8(dev_find_slot(0, PCI_DEVFN(0, 0)), 0x9e);
	if (reg8 & 1) {
		int tseg_size = 0;
		printk(BIOS_DEBUG, "TSEG decoded, subtracting ");
		reg8 >>= 1;
		reg8 &= 3;
		switch (reg8) {
		case 0:
			tseg_size = 1024; /* TSEG = 1M */
			break;
		case 1:
			tseg_size = 2048; /* TSEG = 2M */
			break;
		case 2:
			tseg_size = 8192; /* TSEG = 8M */
			break;
		}

		printk(BIOS_DEBUG, "%dM\n", tseg_size >> 10);
		tomk_stolen -= tseg_size;

		/* For reserving TSEG memory in the memory map */
		tseg_memory_base = tomk_stolen * 1024ULL;
		tseg_memory_size = tseg_size * 1024ULL;
	}

	reg16 = pci_read_config16(dev_find_slot(0, PCI_DEVFN(2, 0)), GGC);
	if (!(reg16 & 2)) {
		int uma_size = 0;
		printk(BIOS_DEBUG, "IGD decoded, subtracting ");
		reg16 >>= 4;
		reg16 &= 7;
		switch (reg16) {
		case 1:
			uma_size = 1024;
			break;
		case 2:
			uma_size = 4096;
			break;
		case 3:
			uma_size = 8192;
			break;
		}
		printk(BIOS_DEBUG, "%dM UMA\n", uma_size >> 10);
		tomk_stolen -= uma_size;

		/* For reserving UMA memory in the memory map. */
		uma_memory_base = tomk_stolen * 1024ULL;
		uma_memory_size = uma_size * 1024ULL;
	}

	/*
	 * The following needs to be 2 lines, otherwise the second
	 * number is always 0.
	 */
	printk(BIOS_INFO, "Available memory: %dK", (u32) tomk);
	printk(BIOS_INFO, " (%dM)\n", (u32) (tomk >> 10));

	/* Report the memory regions. */
	ram_resource(dev, 3, 0, 640);
	ram_resource(dev, 4, 768, (tomk - 768));
	uma_resource(dev, 5, uma_memory_base >> 10, uma_memory_size >> 10);
	mmio_resource(dev, 6, tseg_memory_base >> 10, tseg_memory_size >> 10);

	add_fixed_resources(dev, 7);

	assign_resources(dev->link_list);

	set_late_cbmem_top(tomk * 1024 - uma_memory_size - tseg_memory_base);
}

/*
 * TODO: We could determine how many PCIe busses we need in the bar. For now
 * that number is hardcoded to a max of 64.
 * See e7525/northbridge.c for an example.
 */
static struct device_operations pci_domain_ops = {
	.read_resources		= pci_domain_read_resources,
	.set_resources		= pci_domain_set_resources,
	.enable_resources	= NULL,
	.init			= NULL,
	.scan_bus		= pci_domain_scan_bus,
	.ops_pci_bus		= pci_bus_default_ops,
};

static void mc_read_resources(device_t dev)
{
	u32 pcie_config_base;
	int buses;

	pci_dev_read_resources(dev);

	/*
	 * We use 0xcf as an unused index for our PCIe bar so that we find
	 * it again.
	 */
	buses = get_pcie_bar(&pcie_config_base);
	if (buses) {
		struct resource *resource = new_resource(dev, 0xcf);
		mmconf_resource_init(resource, pcie_config_base, buses);
	}
}

static void intel_set_subsystem(device_t dev, unsigned vendor, unsigned device)
{
	if (!vendor || !device) {
		pci_write_config32(dev, PCI_SUBSYSTEM_VENDOR_ID,
				   pci_read_config32(dev, PCI_VENDOR_ID));
	} else {
		pci_write_config32(dev, PCI_SUBSYSTEM_VENDOR_ID,
			((device & 0xffff) << 16) | (vendor & 0xffff));
	}
}

static struct pci_operations intel_pci_ops = {
	.set_subsystem = intel_set_subsystem,
};

static struct device_operations mc_ops = {
	.read_resources		= mc_read_resources,
	.set_resources		= pci_dev_set_resources,
	.enable_resources	= pci_dev_enable_resources,
	.acpi_fill_ssdt_generator = generate_cpu_entries,
	.scan_bus		= 0,
	.ops_pci		= &intel_pci_ops,
};

static const struct pci_driver mc_driver __pci_driver = {
	.ops	= &mc_ops,
	.vendor	= PCI_VENDOR_ID_INTEL,
	.device	= 0x8100,
};

static void cpu_bus_init(device_t dev)
{
	initialize_cpus(dev->link_list);
}

static struct device_operations cpu_bus_ops = {
	.read_resources		= DEVICE_NOOP,
	.set_resources		= DEVICE_NOOP,
	.enable_resources	= DEVICE_NOOP,
	.init			= cpu_bus_init,
	.scan_bus		= 0,
};

static void enable_dev(device_t dev)
{
	/* Set the operations if it is a special bus type. */
	if (dev->path.type == DEVICE_PATH_DOMAIN) {
		dev->ops = &pci_domain_ops;
	} else if (dev->path.type == DEVICE_PATH_CPU_CLUSTER) {
		dev->ops = &cpu_bus_ops;
	}
}

struct chip_operations northbridge_intel_sch_ops = {
	CHIP_NAME("Intel SCH Northbridge")
	.enable_dev = enable_dev,
};
