summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/pci_root.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/acpi/pci_root.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/acpi/pci_root.c')
-rw-r--r--drivers/acpi/pci_root.c1085
1 files changed, 1085 insertions, 0 deletions
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
new file mode 100644
index 0000000000..84030804a7
--- /dev/null
+++ b/drivers/acpi/pci_root.c
@@ -0,0 +1,1085 @@
+// 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, buf);
+}
+
+static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
+{
+ decode_osc_bits(root, msg, word, pci_osc_support_bit,
+ ARRAY_SIZE(pci_osc_support_bit));
+}
+
+static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
+{
+ decode_osc_bits(root, msg, word, pci_osc_control_bit,
+ ARRAY_SIZE(pci_osc_control_bit));
+}
+
+static void decode_cxl_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
+{
+ decode_osc_bits(root, msg, word, cxl_osc_support_bit,
+ ARRAY_SIZE(cxl_osc_support_bit));
+}
+
+static void decode_cxl_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
+{
+ decode_osc_bits(root, msg, word, cxl_osc_control_bit,
+ ARRAY_SIZE(cxl_osc_control_bit));
+}
+
+static inline bool is_pcie(struct acpi_pci_root *root)
+{
+ return root->bridge_type == ACPI_BRIDGE_TYPE_PCIE;
+}
+
+static inline bool is_cxl(struct acpi_pci_root *root)
+{
+ return root->bridge_type == ACPI_BRIDGE_TYPE_CXL;
+}
+
+static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
+static u8 cxl_osc_uuid_str[] = "68F2D50B-C469-4d8A-BD3D-941A103FD3FC";
+
+static char *to_uuid(struct acpi_pci_root *root)
+{
+ if (is_cxl(root))
+ return cxl_osc_uuid_str;
+ return pci_osc_uuid_str;
+}
+
+static int cap_length(struct acpi_pci_root *root)
+{
+ if (is_cxl(root))
+ return sizeof(u32) * OSC_CXL_CAPABILITY_DWORDS;
+ return sizeof(u32) * OSC_PCI_CAPABILITY_DWORDS;
+}
+
+static acpi_status acpi_pci_run_osc(struct acpi_pci_root *root,
+ const u32 *capbuf, u32 *pci_control,
+ u32 *cxl_control)
+{
+ struct acpi_osc_context context = {
+ .uuid_str = to_uuid(root),
+ .rev = 1,
+ .cap.length = cap_length(root),
+ .cap.pointer = (void *)capbuf,
+ };
+ acpi_status status;
+
+ status = acpi_run_osc(root->device->handle, &context);
+ if (ACPI_SUCCESS(status)) {
+ *pci_control = acpi_osc_ctx_get_pci_control(&context);
+ if (is_cxl(root))
+ *cxl_control = acpi_osc_ctx_get_cxl_control(&context);
+ kfree(context.ret.pointer);
+ }
+ return status;
+}
+
+static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 support,
+ u32 *control, u32 cxl_support,
+ u32 *cxl_control)
+{
+ acpi_status status;
+ u32 pci_result, cxl_result, capbuf[OSC_CXL_CAPABILITY_DWORDS];
+
+ support |= root->osc_support_set;
+
+ capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
+ capbuf[OSC_SUPPORT_DWORD] = support;
+ capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
+
+ if (is_cxl(root)) {
+ cxl_support |= root->osc_ext_support_set;
+ capbuf[OSC_EXT_SUPPORT_DWORD] = cxl_support;
+ capbuf[OSC_EXT_CONTROL_DWORD] = *cxl_control | root->osc_ext_control_set;
+ }
+
+retry:
+ status = acpi_pci_run_osc(root, capbuf, &pci_result, &cxl_result);
+ if (ACPI_SUCCESS(status)) {
+ root->osc_support_set = support;
+ *control = pci_result;
+ if (is_cxl(root)) {
+ root->osc_ext_support_set = cxl_support;
+ *cxl_control = cxl_result;
+ }
+ } else if (is_cxl(root)) {
+ /*
+ * CXL _OSC is optional on CXL 1.1 hosts. Fall back to PCIe _OSC
+ * upon any failure using CXL _OSC.
+ */
+ root->bridge_type = ACPI_BRIDGE_TYPE_PCIE;
+ goto retry;
+ }
+ return status;
+}
+
+struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
+{
+ struct acpi_device *device = acpi_fetch_acpi_dev(handle);
+ struct acpi_pci_root *root;
+
+ if (!device || acpi_match_device_ids(device, root_device_ids))
+ return NULL;
+
+ root = acpi_driver_data(device);
+
+ return root;
+}
+EXPORT_SYMBOL_GPL(acpi_pci_find_root);
+
+struct acpi_handle_node {
+ struct list_head node;
+ acpi_handle handle;
+};
+
+/**
+ * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
+ * @handle: the handle in question
+ *
+ * Given an ACPI CA handle, the desired PCI device is located in the
+ * list of PCI devices.
+ *
+ * If the device is found, its reference count is increased and this
+ * function returns a pointer to its data structure. The caller must
+ * decrement the reference count by calling pci_dev_put().
+ * If no device is found, %NULL is returned.
+ */
+struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
+{
+ struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
+ struct acpi_device_physical_node *pn;
+ struct pci_dev *pci_dev = NULL;
+
+ if (!adev)
+ return NULL;
+
+ mutex_lock(&adev->physical_node_lock);
+
+ list_for_each_entry(pn, &adev->physical_node_list, node) {
+ if (dev_is_pci(pn->dev)) {
+ get_device(pn->dev);
+ pci_dev = to_pci_dev(pn->dev);
+ break;
+ }
+ }
+
+ mutex_unlock(&adev->physical_node_lock);
+
+ return pci_dev;
+}
+EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
+
+/**
+ * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
+ * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
+ * @mask: Mask of _OSC bits to request control of, place to store control mask.
+ * @support: _OSC supported capability.
+ * @cxl_mask: Mask of CXL _OSC control bits, place to store control mask.
+ * @cxl_support: CXL _OSC supported capability.
+ *
+ * Run _OSC query for @mask and if that is successful, compare the returned
+ * mask of control bits with @req. If all of the @req bits are set in the
+ * returned mask, run _OSC request for it.
+ *
+ * The variable at the @mask address may be modified regardless of whether or
+ * not the function returns success. On success it will contain the mask of
+ * _OSC bits the BIOS has granted control of, but its contents are meaningless
+ * on failure.
+ **/
+static acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask,
+ u32 support, u32 *cxl_mask,
+ u32 cxl_support)
+{
+ u32 req = OSC_PCI_EXPRESS_CAPABILITY_CONTROL;
+ struct acpi_pci_root *root;
+ acpi_status status;
+ u32 ctrl, cxl_ctrl = 0, capbuf[OSC_CXL_CAPABILITY_DWORDS];
+
+ if (!mask)
+ return AE_BAD_PARAMETER;
+
+ root = acpi_pci_find_root(handle);
+ if (!root)
+ return AE_NOT_EXIST;
+
+ ctrl = *mask;
+ *mask |= root->osc_control_set;
+
+ if (is_cxl(root)) {
+ cxl_ctrl = *cxl_mask;
+ *cxl_mask |= root->osc_ext_control_set;
+ }
+
+ /* Need to check the available controls bits before requesting them. */
+ do {
+ u32 pci_missing = 0, cxl_missing = 0;
+
+ status = acpi_pci_query_osc(root, support, mask, cxl_support,
+ cxl_mask);
+ if (ACPI_FAILURE(status))
+ return status;
+ if (is_cxl(root)) {
+ if (ctrl == *mask && cxl_ctrl == *cxl_mask)
+ break;
+ pci_missing = ctrl & ~(*mask);
+ cxl_missing = cxl_ctrl & ~(*cxl_mask);
+ } else {
+ if (ctrl == *mask)
+ break;
+ pci_missing = ctrl & ~(*mask);
+ }
+ if (pci_missing)
+ decode_osc_control(root, "platform does not support",
+ pci_missing);
+ if (cxl_missing)
+ decode_cxl_osc_control(root, "CXL platform does not support",
+ cxl_missing);
+ ctrl = *mask;
+ cxl_ctrl = *cxl_mask;
+ } while (*mask || *cxl_mask);
+
+ /* No need to request _OSC if the control was already granted. */
+ if ((root->osc_control_set & ctrl) == ctrl &&
+ (root->osc_ext_control_set & cxl_ctrl) == cxl_ctrl)
+ return AE_OK;
+
+ if ((ctrl & req) != req) {
+ decode_osc_control(root, "not requesting control; platform does not support",
+ req & ~(ctrl));
+ return AE_SUPPORT;
+ }
+
+ capbuf[OSC_QUERY_DWORD] = 0;
+ capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
+ capbuf[OSC_CONTROL_DWORD] = ctrl;
+ if (is_cxl(root)) {
+ capbuf[OSC_EXT_SUPPORT_DWORD] = root->osc_ext_support_set;
+ capbuf[OSC_EXT_CONTROL_DWORD] = cxl_ctrl;
+ }
+
+ status = acpi_pci_run_osc(root, capbuf, mask, cxl_mask);
+ if (ACPI_FAILURE(status))
+ return status;
+
+ root->osc_control_set = *mask;
+ root->osc_ext_control_set = *cxl_mask;
+ return AE_OK;
+}
+
+static u32 calculate_support(void)
+{
+ u32 support;
+
+ /*
+ * All supported architectures that use ACPI have support for
+ * PCI domains, so we indicate this in _OSC support capabilities.
+ */
+ support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
+ support |= OSC_PCI_HPX_TYPE_3_SUPPORT;
+ if (pci_ext_cfg_avail())
+ support |= OSC_PCI_EXT_CONFIG_SUPPORT;
+ if (pcie_aspm_support_enabled())
+ support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
+ if (pci_msi_enabled())
+ support |= OSC_PCI_MSI_SUPPORT;
+ if (IS_ENABLED(CONFIG_PCIE_EDR))
+ support |= OSC_PCI_EDR_SUPPORT;
+
+ return support;
+}
+
+/*
+ * Background on hotplug support, and making it depend on only
+ * CONFIG_HOTPLUG_PCI_PCIE vs. also considering CONFIG_MEMORY_HOTPLUG:
+ *
+ * CONFIG_ACPI_HOTPLUG_MEMORY does depend on CONFIG_MEMORY_HOTPLUG, but
+ * there is no existing _OSC for memory hotplug support. The reason is that
+ * ACPI memory hotplug requires the OS to acknowledge / coordinate with
+ * memory plug events via a scan handler. On the CXL side the equivalent
+ * would be if Linux supported the Mechanical Retention Lock [1], or
+ * otherwise had some coordination for the driver of a PCI device
+ * undergoing hotplug to be consulted on whether the hotplug should
+ * proceed or not.
+ *
+ * The concern is that if Linux says no to supporting CXL hotplug then
+ * the BIOS may say no to giving the OS hotplug control of any other PCIe
+ * device. So the question here is not whether hotplug is enabled, it's
+ * whether it is handled natively by the at all OS, and if
+ * CONFIG_HOTPLUG_PCI_PCIE is enabled then the answer is "yes".
+ *
+ * Otherwise, the plan for CXL coordinated remove, since the kernel does
+ * not support blocking hotplug, is to require the memory device to be
+ * disabled before hotplug is attempted. When CONFIG_MEMORY_HOTPLUG is
+ * disabled that step will fail and the remove attempt cancelled by the
+ * user. If that is not honored and the card is removed anyway then it
+ * does not matter if CONFIG_MEMORY_HOTPLUG is enabled or not, it will
+ * cause a crash and other badness.
+ *
+ * Therefore, just say yes to CXL hotplug and require removal to
+ * be coordinated by userspace unless and until the kernel grows better
+ * mechanisms for doing "managed" removal of devices in consultation with
+ * the driver.
+ *
+ * [1]: https://lore.kernel.org/all/20201122014203.4706-1-ashok.raj@intel.com/
+ */
+static u32 calculate_cxl_support(void)
+{
+ u32 support;
+
+ support = OSC_CXL_2_0_PORT_DEV_REG_ACCESS_SUPPORT;
+ support |= OSC_CXL_1_1_PORT_REG_ACCESS_SUPPORT;
+ if (pci_aer_available())
+ support |= OSC_CXL_PROTOCOL_ERR_REPORTING_SUPPORT;
+ if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
+ support |= OSC_CXL_NATIVE_HP_SUPPORT;
+
+ return support;
+}
+
+static u32 calculate_control(void)
+{
+ u32 control;
+
+ control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
+ | OSC_PCI_EXPRESS_PME_CONTROL;
+
+ if (IS_ENABLED(CONFIG_PCIEASPM))
+ control |= OSC_PCI_EXPRESS_LTR_CONTROL;
+
+ if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
+ control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
+
+ if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
+ control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
+
+ if (pci_aer_available())
+ control |= OSC_PCI_EXPRESS_AER_CONTROL;
+
+ /*
+ * Per the Downstream Port Containment Related Enhancements ECN to
+ * the PCI Firmware Spec, r3.2, sec 4.5.1, table 4-5,
+ * OSC_PCI_EXPRESS_DPC_CONTROL indicates the OS supports both DPC
+ * and EDR.
+ */
+ if (IS_ENABLED(CONFIG_PCIE_DPC) && IS_ENABLED(CONFIG_PCIE_EDR))
+ control |= OSC_PCI_EXPRESS_DPC_CONTROL;
+
+ return control;
+}
+
+static u32 calculate_cxl_control(void)
+{
+ u32 control = 0;
+
+ if (IS_ENABLED(CONFIG_MEMORY_FAILURE))
+ control |= OSC_CXL_ERROR_REPORTING_CONTROL;
+
+ return control;
+}
+
+static bool os_control_query_checks(struct acpi_pci_root *root, u32 support)
+{
+ struct acpi_device *device = root->device;
+
+ if (pcie_ports_disabled) {
+ dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
+ return false;
+ }
+
+ if ((support & ACPI_PCIE_REQ_SUPPORT) != ACPI_PCIE_REQ_SUPPORT) {
+ decode_osc_support(root, "not requesting OS control; OS requires",
+ ACPI_PCIE_REQ_SUPPORT);
+ return false;
+ }
+
+ return true;
+}
+
+static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm)
+{
+ u32 support, control = 0, requested = 0;
+ u32 cxl_support = 0, cxl_control = 0, cxl_requested = 0;
+ acpi_status status;
+ struct acpi_device *device = root->device;
+ acpi_handle handle = device->handle;
+
+ /*
+ * Apple always return failure on _OSC calls when _OSI("Darwin") has
+ * been called successfully. We know the feature set supported by the
+ * platform, so avoid calling _OSC at all
+ */
+ if (x86_apple_machine) {
+ root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
+ decode_osc_control(root, "OS assumes control of",
+ root->osc_control_set);
+ return;
+ }
+
+ support = calculate_support();
+
+ decode_osc_support(root, "OS supports", support);
+
+ if (os_control_query_checks(root, support))
+ requested = control = calculate_control();
+
+ if (is_cxl(root)) {
+ cxl_support = calculate_cxl_support();
+ decode_cxl_osc_support(root, "OS supports", cxl_support);
+ cxl_requested = cxl_control = calculate_cxl_control();
+ }
+
+ status = acpi_pci_osc_control_set(handle, &control, support,
+ &cxl_control, cxl_support);
+ if (ACPI_SUCCESS(status)) {
+ if (control)
+ decode_osc_control(root, "OS now controls", control);
+ if (cxl_control)
+ decode_cxl_osc_control(root, "OS now controls",
+ cxl_control);
+
+ if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
+ /*
+ * We have ASPM control, but the FADT indicates that
+ * it's unsupported. Leave existing configuration
+ * intact and prevent the OS from touching it.
+ */
+ dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
+ *no_aspm = 1;
+ }
+ } else {
+ /*
+ * We want to disable ASPM here, but aspm_disabled
+ * needs to remain in its state from boot so that we
+ * properly handle PCIe 1.1 devices. So we set this
+ * flag here, to defer the action until after the ACPI
+ * root scan.
+ */
+ *no_aspm = 1;
+
+ /* _OSC is optional for PCI host bridges */
+ if (status == AE_NOT_FOUND && !is_pcie(root))
+ return;
+
+ if (control) {
+ decode_osc_control(root, "OS requested", requested);
+ decode_osc_control(root, "platform willing to grant", control);
+ }
+ if (cxl_control) {
+ decode_cxl_osc_control(root, "OS requested", cxl_requested);
+ decode_cxl_osc_control(root, "platform willing to grant",
+ cxl_control);
+ }
+
+ dev_info(&device->dev, "_OSC: platform retains control of PCIe features (%s)\n",
+ acpi_format_exception(status));
+ }
+}
+
+static int acpi_pci_root_add(struct acpi_device *device,
+ const struct acpi_device_id *not_used)
+{
+ unsigned long long segment, bus;
+ acpi_status status;
+ int result;
+ struct acpi_pci_root *root;
+ acpi_handle handle = device->handle;
+ int no_aspm = 0;
+ bool hotadd = system_state == SYSTEM_RUNNING;
+ const char *acpi_hid;
+
+ root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
+ if (!root)
+ return -ENOMEM;
+
+ segment = 0;
+ status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
+ &segment);
+ if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
+ dev_err(&device->dev, "can't evaluate _SEG\n");
+ result = -ENODEV;
+ goto end;
+ }
+
+ /* Check _CRS first, then _BBN. If no _BBN, default to zero. */
+ root->secondary.flags = IORESOURCE_BUS;
+ status = try_get_root_bridge_busnr(handle, &root->secondary);
+ if (ACPI_FAILURE(status)) {
+ /*
+ * We need both the start and end of the downstream bus range
+ * to interpret _CBA (MMCONFIG base address), so it really is
+ * supposed to be in _CRS. If we don't find it there, all we
+ * can do is assume [_BBN-0xFF] or [0-0xFF].
+ */
+ root->secondary.end = 0xFF;
+ dev_warn(&device->dev,
+ FW_BUG "no secondary bus range in _CRS\n");
+ status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
+ NULL, &bus);
+ if (ACPI_SUCCESS(status))
+ root->secondary.start = bus;
+ else if (status == AE_NOT_FOUND)
+ root->secondary.start = 0;
+ else {
+ dev_err(&device->dev, "can't evaluate _BBN\n");
+ result = -ENODEV;
+ goto end;
+ }
+ }
+
+ root->device = device;
+ root->segment = segment & 0xFFFF;
+ strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
+ strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
+ device->driver_data = root;
+
+ if (hotadd && dmar_device_add(handle)) {
+ result = -ENXIO;
+ goto end;
+ }
+
+ pr_info("%s [%s] (domain %04x %pR)\n",
+ acpi_device_name(device), acpi_device_bid(device),
+ root->segment, &root->secondary);
+
+ root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
+
+ acpi_hid = acpi_device_hid(root->device);
+ if (strcmp(acpi_hid, "PNP0A08") == 0)
+ root->bridge_type = ACPI_BRIDGE_TYPE_PCIE;
+ else if (strcmp(acpi_hid, "ACPI0016") == 0)
+ root->bridge_type = ACPI_BRIDGE_TYPE_CXL;
+ else
+ dev_dbg(&device->dev, "Assuming non-PCIe host bridge\n");
+
+ negotiate_os_control(root, &no_aspm);
+
+ /*
+ * TBD: Need PCI interface for enumeration/configuration of roots.
+ */
+
+ /*
+ * Scan the Root Bridge
+ * --------------------
+ * Must do this prior to any attempt to bind the root device, as the
+ * PCI namespace does not get created until this call is made (and
+ * thus the root bridge's pci_dev does not exist).
+ */
+ root->bus = pci_acpi_scan_root(root);
+ if (!root->bus) {
+ dev_err(&device->dev,
+ "Bus %04x:%02x not present in PCI namespace\n",
+ root->segment, (unsigned int)root->secondary.start);
+ device->driver_data = NULL;
+ result = -ENODEV;
+ goto remove_dmar;
+ }
+
+ if (no_aspm)
+ pcie_no_aspm();
+
+ pci_acpi_add_bus_pm_notifier(device);
+ device_set_wakeup_capable(root->bus->bridge, device->wakeup.flags.valid);
+
+ if (hotadd) {
+ pcibios_resource_survey_bus(root->bus);
+ pci_assign_unassigned_root_bus_resources(root->bus);
+ /*
+ * This is only called for the hotadd case. For the boot-time
+ * case, we need to wait until after PCI initialization in
+ * order to deal with IOAPICs mapped in on a PCI BAR.
+ *
+ * This is currently x86-specific, because acpi_ioapic_add()
+ * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
+ * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
+ * (see drivers/acpi/Kconfig).
+ */
+ acpi_ioapic_add(root->device->handle);
+ }
+
+ pci_lock_rescan_remove();
+ pci_bus_add_devices(root->bus);
+ pci_unlock_rescan_remove();
+ return 1;
+
+remove_dmar:
+ if (hotadd)
+ dmar_device_remove(handle);
+end:
+ kfree(root);
+ return result;
+}
+
+static void acpi_pci_root_remove(struct acpi_device *device)
+{
+ struct acpi_pci_root *root = acpi_driver_data(device);
+
+ pci_lock_rescan_remove();
+
+ pci_stop_root_bus(root->bus);
+
+ pci_ioapic_remove(root);
+ device_set_wakeup_capable(root->bus->bridge, false);
+ pci_acpi_remove_bus_pm_notifier(device);
+
+ pci_remove_root_bus(root->bus);
+ WARN_ON(acpi_ioapic_remove(root));
+
+ dmar_device_remove(device->handle);
+
+ pci_unlock_rescan_remove();
+
+ kfree(root);
+}
+
+/*
+ * Following code to support acpi_pci_root_create() is copied from
+ * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
+ * and ARM64.
+ */
+static void acpi_pci_root_validate_resources(struct device *dev,
+ struct list_head *resources,
+ unsigned long type)
+{
+ LIST_HEAD(list);
+ struct resource *res1, *res2, *root = NULL;
+ struct resource_entry *tmp, *entry, *entry2;
+
+ BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
+ root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
+
+ list_splice_init(resources, &list);
+ resource_list_for_each_entry_safe(entry, tmp, &list) {
+ bool free = false;
+ resource_size_t end;
+
+ res1 = entry->res;
+ if (!(res1->flags & type))
+ goto next;
+
+ /* Exclude non-addressable range or non-addressable portion */
+ end = min(res1->end, root->end);
+ if (end <= res1->start) {
+ dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
+ res1);
+ free = true;
+ goto next;
+ } else if (res1->end != end) {
+ dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
+ res1, (unsigned long long)end + 1,
+ (unsigned long long)res1->end);
+ res1->end = end;
+ }
+
+ resource_list_for_each_entry(entry2, resources) {
+ res2 = entry2->res;
+ if (!(res2->flags & type))
+ continue;
+
+ /*
+ * I don't like throwing away windows because then
+ * our resources no longer match the ACPI _CRS, but
+ * the kernel resource tree doesn't allow overlaps.
+ */
+ if (resource_union(res1, res2, res2)) {
+ dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
+ res2, res1);
+ free = true;
+ goto next;
+ }
+ }
+
+next:
+ resource_list_del(entry);
+ if (free)
+ resource_list_free_entry(entry);
+ else
+ resource_list_add_tail(entry, resources);
+ }
+}
+
+static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
+ struct resource_entry *entry)
+{
+#ifdef PCI_IOBASE
+ struct resource *res = entry->res;
+ resource_size_t cpu_addr = res->start;
+ resource_size_t pci_addr = cpu_addr - entry->offset;
+ resource_size_t length = resource_size(res);
+ unsigned long port;
+
+ if (pci_register_io_range(fwnode, cpu_addr, length))
+ goto err;
+
+ port = pci_address_to_pio(cpu_addr);
+ if (port == (unsigned long)-1)
+ goto err;
+
+ res->start = port;
+ res->end = port + length - 1;
+ entry->offset = port - pci_addr;
+
+ if (pci_remap_iospace(res, cpu_addr) < 0)
+ goto err;
+
+ pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
+ return;
+err:
+ res->flags |= IORESOURCE_DISABLED;
+#endif
+}
+
+int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
+{
+ int ret;
+ struct list_head *list = &info->resources;
+ struct acpi_device *device = info->bridge;
+ struct resource_entry *entry, *tmp;
+ unsigned long flags;
+
+ flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
+ ret = acpi_dev_get_resources(device, list,
+ acpi_dev_filter_resource_type_cb,
+ (void *)flags);
+ if (ret < 0)
+ dev_warn(&device->dev,
+ "failed to parse _CRS method, error code %d\n", ret);
+ else if (ret == 0)
+ dev_dbg(&device->dev,
+ "no IO and memory resources present in _CRS\n");
+ else {
+ resource_list_for_each_entry_safe(entry, tmp, list) {
+ if (entry->res->flags & IORESOURCE_IO)
+ acpi_pci_root_remap_iospace(&device->fwnode,
+ entry);
+
+ if (entry->res->flags & IORESOURCE_DISABLED)
+ resource_list_destroy_entry(entry);
+ else
+ entry->res->name = info->name;
+ }
+ acpi_pci_root_validate_resources(&device->dev, list,
+ IORESOURCE_MEM);
+ acpi_pci_root_validate_resources(&device->dev, list,
+ IORESOURCE_IO);
+ }
+
+ return ret;
+}
+
+static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
+{
+ struct resource_entry *entry, *tmp;
+ struct resource *res, *conflict, *root = NULL;
+
+ resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
+ res = entry->res;
+ if (res->flags & IORESOURCE_MEM)
+ root = &iomem_resource;
+ else if (res->flags & IORESOURCE_IO)
+ root = &ioport_resource;
+ else
+ continue;
+
+ /*
+ * Some legacy x86 host bridge drivers use iomem_resource and
+ * ioport_resource as default resource pool, skip it.
+ */
+ if (res == root)
+ continue;
+
+ conflict = insert_resource_conflict(root, res);
+ if (conflict) {
+ dev_info(&info->bridge->dev,
+ "ignoring host bridge window %pR (conflicts with %s %pR)\n",
+ res, conflict->name, conflict);
+ resource_list_destroy_entry(entry);
+ }
+ }
+}
+
+static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
+{
+ struct resource *res;
+ struct resource_entry *entry, *tmp;
+
+ if (!info)
+ return;
+
+ resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
+ res = entry->res;
+ if (res->parent &&
+ (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
+ release_resource(res);
+ resource_list_destroy_entry(entry);
+ }
+
+ info->ops->release_info(info);
+}
+
+static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
+{
+ struct resource *res;
+ struct resource_entry *entry;
+
+ resource_list_for_each_entry(entry, &bridge->windows) {
+ res = entry->res;
+ if (res->flags & IORESOURCE_IO)
+ pci_unmap_iospace(res);
+ if (res->parent &&
+ (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
+ release_resource(res);
+ }
+ __acpi_pci_root_release_info(bridge->release_data);
+}
+
+struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
+ struct acpi_pci_root_ops *ops,
+ struct acpi_pci_root_info *info,
+ void *sysdata)
+{
+ int ret, busnum = root->secondary.start;
+ struct acpi_device *device = root->device;
+ int node = acpi_get_node(device->handle);
+ struct pci_bus *bus;
+ struct pci_host_bridge *host_bridge;
+ union acpi_object *obj;
+
+ info->root = root;
+ info->bridge = device;
+ info->ops = ops;
+ INIT_LIST_HEAD(&info->resources);
+ snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
+ root->segment, busnum);
+
+ if (ops->init_info && ops->init_info(info))
+ goto out_release_info;
+ if (ops->prepare_resources)
+ ret = ops->prepare_resources(info);
+ else
+ ret = acpi_pci_probe_root_resources(info);
+ if (ret < 0)
+ goto out_release_info;
+
+ pci_acpi_root_add_resources(info);
+ pci_add_resource(&info->resources, &root->secondary);
+ bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
+ sysdata, &info->resources);
+ if (!bus)
+ goto out_release_info;
+
+ host_bridge = to_pci_host_bridge(bus->bridge);
+ if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
+ host_bridge->native_pcie_hotplug = 0;
+ if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
+ host_bridge->native_shpc_hotplug = 0;
+ if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
+ host_bridge->native_aer = 0;
+ if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
+ host_bridge->native_pme = 0;
+ if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
+ host_bridge->native_ltr = 0;
+ if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL))
+ host_bridge->native_dpc = 0;
+
+ if (!(root->osc_ext_control_set & OSC_CXL_ERROR_REPORTING_CONTROL))
+ host_bridge->native_cxl_error = 0;
+
+ /*
+ * Evaluate the "PCI Boot Configuration" _DSM Function. If it
+ * exists and returns 0, we must preserve any PCI resource
+ * assignments made by firmware for this host bridge.
+ */
+ obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 1,
+ DSM_PCI_PRESERVE_BOOT_CONFIG, NULL);
+ if (obj && obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 0)
+ host_bridge->preserve_config = 1;
+ ACPI_FREE(obj);
+
+ acpi_dev_power_up_children_with_adr(device);
+
+ pci_scan_child_bus(bus);
+ pci_set_host_bridge_release(host_bridge, acpi_pci_root_release_info,
+ info);
+ if (node != NUMA_NO_NODE)
+ dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
+ return bus;
+
+out_release_info:
+ __acpi_pci_root_release_info(info);
+ return NULL;
+}
+
+void __init acpi_pci_root_init(void)
+{
+ if (acpi_pci_disabled)
+ return;
+
+ pci_acpi_crs_quirks();
+ acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
+}