--- /dev/null
+/*
+ * 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>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * 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; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#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/pci-aspm.h>
+#include <linux/dmar.h>
+#include <linux/acpi.h>
+#include <linux/slab.h>
+#include <linux/dmi.h>
+#include <acpi/apei.h> /* for acpi_hest_init() */
+
+#include "internal.h"
+
+#define _COMPONENT ACPI_PCI_COMPONENT
+ACPI_MODULE_NAME("pci_root");
+#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,
+ },
+};
+
+static DEFINE_MUTEX(osc_lock);
+
+/**
+ * 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)
+{
+ int ret;
+ struct acpi_device *device;
+
+ ret = acpi_bus_get_device(handle, &device);
+ if (ret)
+ 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" },
+};
+
+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" },
+};
+
+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 += snprintf(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 u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
+
+static acpi_status acpi_pci_run_osc(acpi_handle handle,
+ const u32 *capbuf, u32 *retval)
+{
+ struct acpi_osc_context context = {
+ .uuid_str = pci_osc_uuid_str,
+ .rev = 1,
+ .cap.length = 12,
+ .cap.pointer = (void *)capbuf,
+ };
+ acpi_status status;
+
+ status = acpi_run_osc(handle, &context);
+ if (ACPI_SUCCESS(status)) {
+ *retval = *((u32 *)(context.ret.pointer + 8));
+ kfree(context.ret.pointer);
+ }
+ return status;
+}
+
+static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
+ u32 support,
+ u32 *control)
+{
+ acpi_status status;
+ u32 result, capbuf[3];
+
+ support &= OSC_PCI_SUPPORT_MASKS;
+ support |= root->osc_support_set;
+
+ capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
+ capbuf[OSC_SUPPORT_DWORD] = support;
+ if (control) {
+ *control &= OSC_PCI_CONTROL_MASKS;
+ capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
+ } else {
+ /* Run _OSC query only with existing controls. */
+ capbuf[OSC_CONTROL_DWORD] = root->osc_control_set;
+ }
+
+ status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
+ if (ACPI_SUCCESS(status)) {
+ root->osc_support_set = support;
+ if (control)
+ *control = result;
+ }
+ return status;
+}
+
+static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
+{
+ acpi_status status;
+
+ mutex_lock(&osc_lock);
+ status = acpi_pci_query_osc(root, flags, NULL);
+ mutex_unlock(&osc_lock);
+ return status;
+}
+
+struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
+{
+ struct acpi_pci_root *root;
+ struct acpi_device *device;
+
+ if (acpi_bus_get_device(handle, &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)
+{
+ int dev, fn;
+ unsigned long long adr;
+ acpi_status status;
+ acpi_handle phandle;
+ struct pci_bus *pbus;
+ struct pci_dev *pdev = NULL;
+ struct acpi_handle_node *node, *tmp;
+ struct acpi_pci_root *root;
+ LIST_HEAD(device_list);
+
+ /*
+ * Walk up the ACPI CA namespace until we reach a PCI root bridge.
+ */
+ phandle = handle;
+ while (!acpi_is_root_bridge(phandle)) {
+ node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
+ if (!node)
+ goto out;
+
+ INIT_LIST_HEAD(&node->node);
+ node->handle = phandle;
+ list_add(&node->node, &device_list);
+
+ status = acpi_get_parent(phandle, &phandle);
+ if (ACPI_FAILURE(status))
+ goto out;
+ }
+
+ root = acpi_pci_find_root(phandle);
+ if (!root)
+ goto out;
+
+ pbus = root->bus;
+
+ /*
+ * Now, walk back down the PCI device tree until we return to our
+ * original handle. Assumes that everything between the PCI root
+ * bridge and the device we're looking for must be a P2P bridge.
+ */
+ list_for_each_entry(node, &device_list, node) {
+ acpi_handle hnd = node->handle;
+ status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
+ if (ACPI_FAILURE(status))
+ goto out;
+ dev = (adr >> 16) & 0xffff;
+ fn = adr & 0xffff;
+
+ pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
+ if (!pdev || hnd == handle)
+ break;
+
+ pbus = pdev->subordinate;
+ pci_dev_put(pdev);
+
+ /*
+ * This function may be called for a non-PCI device that has a
+ * PCI parent (eg. a disk under a PCI SATA controller). In that
+ * case pdev->subordinate will be NULL for the parent.
+ */
+ if (!pbus) {
+ dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
+ pdev = NULL;
+ break;
+ }
+ }
+out:
+ list_for_each_entry_safe(node, tmp, &device_list, node)
+ kfree(node);
+
+ return pdev;
+}
+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.
+ * @req: Mask of _OSC bits the control of is essential to the caller.
+ *
+ * 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.
+ **/
+acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
+{
+ struct acpi_pci_root *root;
+ acpi_status status = AE_OK;
+ u32 ctrl, capbuf[3];
+
+ if (!mask)
+ return AE_BAD_PARAMETER;
+
+ ctrl = *mask & OSC_PCI_CONTROL_MASKS;
+ if ((ctrl & req) != req)
+ return AE_TYPE;
+
+ root = acpi_pci_find_root(handle);
+ if (!root)
+ return AE_NOT_EXIST;
+
+ mutex_lock(&osc_lock);
+
+ *mask = ctrl | root->osc_control_set;
+ /* No need to evaluate _OSC if the control was already granted. */
+ if ((root->osc_control_set & ctrl) == ctrl)
+ goto out;
+
+ /* Need to check the available controls bits before requesting them. */
+ while (*mask) {
+ status = acpi_pci_query_osc(root, root->osc_support_set, mask);
+ if (ACPI_FAILURE(status))
+ goto out;
+ if (ctrl == *mask)
+ break;
+ decode_osc_control(root, "platform does not support",
+ ctrl & ~(*mask));
+ ctrl = *mask;
+ }
+
+ if ((ctrl & req) != req) {
+ decode_osc_control(root, "not requesting control; platform does not support",
+ req & ~(ctrl));
+ status = AE_SUPPORT;
+ goto out;
+ }
+
+ capbuf[OSC_QUERY_DWORD] = 0;
+ capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
+ capbuf[OSC_CONTROL_DWORD] = ctrl;
+ status = acpi_pci_run_osc(handle, capbuf, mask);
+ if (ACPI_SUCCESS(status))
+ root->osc_control_set = *mask;
+out:
+ mutex_unlock(&osc_lock);
+ return status;
+}
+EXPORT_SYMBOL(acpi_pci_osc_control_set);
+
+static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm)
+{
+ u32 support, control, requested;
+ 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 (dmi_match(DMI_SYS_VENDOR, "Apple Inc.")) {
+ root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
+ decode_osc_control(root, "OS assumes control of",
+ root->osc_control_set);
+ return;
+ }
+
+ /*
+ * 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;
+ 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;
+
+ decode_osc_support(root, "OS supports", support);
+ status = acpi_pci_osc_support(root, support);
+ if (ACPI_FAILURE(status)) {
+ dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
+ acpi_format_exception(status));
+ *no_aspm = 1;
+ return;
+ }
+
+ if (pcie_ports_disabled) {
+ dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
+ return;
+ }
+
+ 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;
+ }
+
+ control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
+ | OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
+ | OSC_PCI_EXPRESS_PME_CONTROL;
+
+ if (pci_aer_available()) {
+ if (aer_acpi_firmware_first())
+ dev_info(&device->dev,
+ "PCIe AER handled by firmware\n");
+ else
+ control |= OSC_PCI_EXPRESS_AER_CONTROL;
+ }
+
+ requested = control;
+ status = acpi_pci_osc_control_set(handle, &control,
+ OSC_PCI_EXPRESS_CAPABILITY_CONTROL);
+ if (ACPI_SUCCESS(status)) {
+ decode_osc_control(root, "OS now controls", 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 {
+ decode_osc_control(root, "OS requested", requested);
+ decode_osc_control(root, "platform willing to grant", control);
+ dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
+ acpi_format_exception(status));
+
+ /*
+ * 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;
+ }
+}
+
+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_BOOTING;
+
+ 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(PREFIX "%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);
+
+ 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);
+ if (device->wakeup.flags.run_wake)
+ device_set_run_wake(root->bus->bridge, true);
+
+ if (hotadd) {
+ pcibios_resource_survey_bus(root->bus);
+ pci_assign_unassigned_root_bus_resources(root->bus);
+ acpi_ioapic_add(root);
+ }
+
+ 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);
+
+ WARN_ON(acpi_ioapic_remove(root));
+
+ device_set_run_wake(root->bus->bridge, false);
+ pci_acpi_remove_bus_pm_notifier(device);
+
+ pci_remove_root_bus(root->bus);
+
+ dmar_device_remove(device->handle);
+
+ pci_unlock_rescan_remove();
+
+ kfree(root);
+}
+
+void __init acpi_pci_root_init(void)
+{
+ acpi_hest_init();
+ if (acpi_pci_disabled)
+ return;
+
+ pci_acpi_crs_quirks();
+ acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
+}
Code Review / kvmfornfv.git / blobdiff