/* SPDX-License-Identifier: GPL-2.0-only */

#include <arch/hpet.h>
#include <cbmem.h>
#include <console/console.h>
#include <commonlib/bsd/helpers.h>
#include <device/pci_def.h>
#include <device/pci_ops.h>
#include <stdint.h>
#include <device/device.h>
#include <boot/tables.h>
#include <acpi/acpi.h>
#include <northbridge/intel/pineview/pineview.h>
#include <cpu/intel/smm_reloc.h>
#include <cpu/x86/smm.h>

/*
 * Reserve everything between A segment and 1MB:
 *
 * 0xa0000 - 0xbffff: legacy VGA
 * 0xc0000 - 0xcffff: VGA OPROM (needed by kernel)
 * 0xe0000 - 0xfffff: SeaBIOS, if used, otherwise DMI
 */

static void add_fixed_resources(struct device *dev, int index)
{
	mmio_range(dev, index++, HPET_BASE_ADDRESS, 0x00100000);
	mmio_from_to(dev, index++, 0xa0000, 0xc0000);
	reserved_ram_from_to(dev, index++, 0xc0000, 1 * MiB);
}

static void mch_domain_read_resources(struct device *dev)
{
	u64 tom, touud;
	u32 tolud;
	u16 index;

	struct device *mch = pcidev_on_root(0, 0);

	index = 3;

	pci_domain_read_resources(dev);

	/* Top of Upper Usable DRAM, including remap */
	touud = pci_read_config16(mch, TOUUD);
	touud <<= 20;

	/* Top of Lower Usable DRAM */
	tolud = pci_read_config16(mch, TOLUD) & 0xfff0;
	tolud <<= 16;

	/* Top of Memory - does not account for any UMA */
	tom = pci_read_config16(mch, TOM) & 0x01ff;
	tom <<= 27;

	printk(BIOS_DEBUG, "TOUUD 0x%llx TOLUD 0x%08x TOM 0x%llx ", touud, tolud, tom);

	/* Graphics memory */
	const u16 ggc = pci_read_config16(mch, GGC);
	const u32 gms_size = decode_igd_memory_size((ggc >> 4) & 0xf) * KiB;
	printk(BIOS_DEBUG, "%uM UMA", gms_size / MiB);

	/* GTT Graphics Stolen Memory Size (GGMS) */
	const u32 gsm_size = decode_igd_gtt_size((ggc >> 8) & 0xf) * KiB;
	printk(BIOS_DEBUG, " and %uM GTT\n", gsm_size / MiB);

	const u32 igd_base = pci_read_config32(mch, GBSM);
	const u32 gtt_base = pci_read_config32(mch, BGSM);

	/* Report the memory regions */
	ram_range(dev, index++, 0, 0xa0000);
	ram_from_to(dev, index++, 1 * MiB, (uintptr_t)cbmem_top());
	uintptr_t tseg_base;
	size_t tseg_size;
	smm_region(&tseg_base, &tseg_size);
	mmio_range(dev, index++, tseg_base, tseg_size);
	mmio_range(dev, index++, gtt_base,  gsm_size);
	mmio_range(dev, index++, igd_base,  gms_size);
	printk(BIOS_DEBUG, "Unused RAM between cbmem_top and TOM: 0x%lx\n",
	       tseg_base - (uintptr_t)cbmem_top());
	reserved_ram_from_to(dev, index++, (uintptr_t)cbmem_top(), tseg_base);

	/*
	 * If > 4GB installed then memory from TOLUD to 4GB
	 * is remapped above TOM, TOUUD will account for both
	 */
	upper_ram_end(dev, index++, touud);

	mmconf_resource(dev, index++);

	add_fixed_resources(dev, index);
}

void northbridge_write_smram(u8 smram)
{
	struct device *dev = pcidev_on_root(0, 0);

	if (!dev)
		die("could not find pci 00:00.0!\n");

	pci_write_config8(dev, SMRAM, smram);
}

static void mch_domain_set_resources(struct device *dev)
{
	struct resource *res;

	for (res = dev->resource_list; res; res = res->next)
		report_resource_stored(dev, res, "");

	assign_resources(dev->link_list);
}

static void mch_domain_init(struct device *dev)
{
	/* Enable SERR */
	pci_or_config16(dev, PCI_COMMAND, PCI_COMMAND_SERR);
}

static const char *northbridge_acpi_name(const struct device *dev)
{
	if (dev->path.type == DEVICE_PATH_DOMAIN)
		return "PCI0";

	if (!is_pci_dev_on_bus(dev, 0))
		return NULL;

	switch (dev->path.pci.devfn) {
	case PCI_DEVFN(0, 0):
		return "MCHC";
	}

	return NULL;
}

static struct device_operations pci_domain_ops = {
	.read_resources	= mch_domain_read_resources,
	.set_resources	= mch_domain_set_resources,
	.init		= mch_domain_init,
	.scan_bus	= pci_host_bridge_scan_bus,
	.acpi_fill_ssdt	= generate_cpu_entries,
	.acpi_name	= northbridge_acpi_name,
};

static struct device_operations cpu_bus_ops = {
	.read_resources   = noop_read_resources,
	.set_resources    = noop_set_resources,
	.init             = mp_cpu_bus_init,
};

static void enable_dev(struct device *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_pineview_ops = {
	.name = "Intel Pineview Northbridge",
	.enable_dev = enable_dev,
};