/* * 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/acpi.h> #include <linux/slab.h> #include <acpi/acpi_bus.h> #include <acpi/acpi_drivers.h> #include <acpi/apei.h> #include "internal.h" #define PREFIX "ACPI: " #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); #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, }; 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_length > 0) && (address.resource_type == ACPI_BUS_NUMBER_RANGE)) { res->start = address.minimum; res->end = address.minimum + 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, int *clear_aspm) { u32 support, control, requested; acpi_status status; struct acpi_device *device = root->device; acpi_handle handle = device->handle; /* * 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. Clear it. */ *clear_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, clear_aspm = 0; 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; 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, &clear_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); result = -ENODEV; goto end; } if (clear_aspm) { dev_info(&device->dev, "Disabling ASPM (FADT indicates it is unsupported)\n"); pcie_clear_aspm(root->bus); } if (no_aspm) pcie_no_aspm(); pci_acpi_add_bus_pm_notifier(device, root->bus); if (device->wakeup.flags.run_wake) device_set_run_wake(root->bus->bridge, true); if (system_state != SYSTEM_BOOTING) { pcibios_resource_survey_bus(root->bus); pci_assign_unassigned_root_bus_resources(root->bus); } pci_bus_add_devices(root->bus); return 1; 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_stop_root_bus(root->bus); device_set_run_wake(root->bus->bridge, false); pci_acpi_remove_bus_pm_notifier(device); pci_remove_root_bus(root->bus); kfree(root); } void __init acpi_pci_root_init(void) { acpi_hest_init(); if (!acpi_pci_disabled) { pci_acpi_crs_quirks(); acpi_scan_add_handler(&pci_root_handler); } } /* Support root bridge hotplug */ static void handle_root_bridge_insertion(acpi_handle handle) { struct acpi_device *device; if (!acpi_bus_get_device(handle, &device)) { dev_printk(KERN_DEBUG, &device->dev, "acpi device already exists; ignoring notify\n"); return; } if (acpi_bus_scan(handle)) acpi_handle_err(handle, "cannot add bridge to acpi list\n"); } static void hotplug_event_root(void *data, u32 type) { acpi_handle handle = data; struct acpi_pci_root *root; acpi_scan_lock_acquire(); root = acpi_pci_find_root(handle); switch (type) { case ACPI_NOTIFY_BUS_CHECK: /* bus enumerate */ acpi_handle_printk(KERN_DEBUG, handle, "Bus check notify on %s\n", __func__); if (root) acpiphp_check_host_bridge(handle); else handle_root_bridge_insertion(handle); break; case ACPI_NOTIFY_DEVICE_CHECK: /* device check */ acpi_handle_printk(KERN_DEBUG, handle, "Device check notify on %s\n", __func__); if (!root) handle_root_bridge_insertion(handle); break; case ACPI_NOTIFY_EJECT_REQUEST: /* request device eject */ acpi_handle_printk(KERN_DEBUG, handle, "Device eject notify on %s\n", __func__); if (!root) break; get_device(&root->device->dev); acpi_scan_lock_release(); acpi_bus_device_eject(root->device, ACPI_NOTIFY_EJECT_REQUEST); return; default: acpi_handle_warn(handle, "notify_handler: unknown event type 0x%x\n", type); break; } acpi_scan_lock_release(); } static void handle_hotplug_event_root(acpi_handle handle, u32 type, void *context) { acpi_hotplug_execute(hotplug_event_root, handle, type); } static acpi_status __init find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv) { acpi_status status; int *count = (int *)context; if (!acpi_is_root_bridge(handle)) return AE_OK; (*count)++; status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY, handle_hotplug_event_root, NULL); if (ACPI_FAILURE(status)) acpi_handle_printk(KERN_DEBUG, handle, "notify handler is not installed, exit status: %u\n", (unsigned int)status); else acpi_handle_printk(KERN_DEBUG, handle, "notify handler is installed\n"); return AE_OK; } void __init acpi_pci_root_hp_init(void) { int num = 0; acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, ACPI_UINT32_MAX, find_root_bridges, NULL, &num, NULL); printk(KERN_DEBUG "Found %d acpi root devices\n", num); }