path: root/drivers/acpi/pci_root.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
 *
 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
 */

#define pr_fmt(fmt) "ACPI: " fmt

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include <linux/pci.h>
#include <linux/pci-acpi.h>
#include <linux/dmar.h>
#include <linux/acpi.h>
#include <linux/slab.h>
#include <linux/dmi.h>
#include <linux/platform_data/x86/apple.h>
#include "internal.h"

#define ACPI_PCI_ROOT_CLASS		"pci_bridge"
#define ACPI_PCI_ROOT_DEVICE_NAME	"PCI Root Bridge"
static int acpi_pci_root_add(struct acpi_device *device,
			     const struct acpi_device_id *not_used);
static void acpi_pci_root_remove(struct acpi_device *device);

static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
{
	acpiphp_check_host_bridge(adev);
	return 0;
}

#define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
				| OSC_PCI_ASPM_SUPPORT \
				| OSC_PCI_CLOCK_PM_SUPPORT \
				| OSC_PCI_MSI_SUPPORT)

static const struct acpi_device_id root_device_ids[] = {
	{"PNP0A03", 0},
	{"", 0},
};

static struct acpi_scan_handler pci_root_handler = {
	.ids = root_device_ids,
	.attach = acpi_pci_root_add,
	.detach = acpi_pci_root_remove,
	.hotplug = {
		.enabled = true,
		.scan_dependent = acpi_pci_root_scan_dependent,
	},
};

/**
 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
 * @handle:  the ACPI CA node in question.
 *
 * Note: we could make this API take a struct acpi_device * instead, but
 * for now, it's more convenient to operate on an acpi_handle.
 */
int acpi_is_root_bridge(acpi_handle handle)
{
	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
	int ret;

	if (!device)
		return 0;

	ret = acpi_match_device_ids(device, root_device_ids);
	if (ret)
		return 0;
	else
		return 1;
}
EXPORT_SYMBOL_GPL(acpi_is_root_bridge);

static acpi_status
get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
{
	struct resource *res = data;
	struct acpi_resource_address64 address;
	acpi_status status;

	status = acpi_resource_to_address64(resource, &address);
	if (ACPI_FAILURE(status))
		return AE_OK;

	if ((address.address.address_length > 0) &&
	    (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
		res->start = address.address.minimum;
		res->end = address.address.minimum + address.address.address_length - 1;
	}

	return AE_OK;
}

static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
					     struct resource *res)
{
	acpi_status status;

	res->start = -1;
	status =
	    acpi_walk_resources(handle, METHOD_NAME__CRS,
				get_root_bridge_busnr_callback, res);
	if (ACPI_FAILURE(status))
		return status;
	if (res->start == -1)
		return AE_ERROR;
	return AE_OK;
}

struct pci_osc_bit_struct {
	u32 bit;
	char *desc;
};

static struct pci_osc_bit_struct pci_osc_support_bit[] = {
	{ OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
	{ OSC_PCI_ASPM_SUPPORT, "ASPM" },
	{ OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
	{ OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
	{ OSC_PCI_MSI_SUPPORT, "MSI" },
	{ OSC_PCI_EDR_SUPPORT, "EDR" },
	{ OSC_PCI_HPX_TYPE_3_SUPPORT, "HPX-Type3" },
};

static struct pci_osc_bit_struct pci_osc_control_bit[] = {
	{ OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
	{ OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
	{ OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
	{ OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
	{ OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
	{ OSC_PCI_EXPRESS_LTR_CONTROL, "LTR" },
	{ OSC_PCI_EXPRESS_DPC_CONTROL, "DPC" },
};

static struct pci_osc_bit_struct cxl_osc_support_bit[] = {
	{ OSC_CXL_1_1_PORT_REG_ACCESS_SUPPORT, "CXL11PortRegAccess" },
	{ OSC_CXL_2_0_PORT_DEV_REG_ACCESS_SUPPORT, "CXL20PortDevRegAccess" },
	{ OSC_CXL_PROTOCOL_ERR_REPORTING_SUPPORT, "CXLProtocolErrorReporting" },
	{ OSC_CXL_NATIVE_HP_SUPPORT, "CXLNativeHotPlug" },
};

static struct pci_osc_bit_struct cxl_osc_control_bit[] = {
	{ OSC_CXL_ERROR_REPORTING_CONTROL, "CXLMemErrorReporting" },
};

static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
			    struct pci_osc_bit_struct *table, int size)
{
	char buf[80];
	int i, len = 0;
	struct pci_osc_bit_struct *entry;

	buf[0] = '\0';
	for (i = 0, entry = table; i < size; i++, entry++)
		if (word & entry->bit)
			len += scnprintf(buf + len, sizeof(buf) - len, "%s%s",
					len ? " " : "", entry->desc);

	dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg