// SPDX-License-Identifier: GPL-2.0 /* * PCI support in ACPI * * Copyright (C) 2005 David Shaohua Li * Copyright (C) 2004 Tom Long Nguyen * Copyright (C) 2004 Intel Corp. */ #include #include #include #include #include #include #include #include #include #include #include #include "pci.h" /* * The GUID is defined in the PCI Firmware Specification available here: * https://www.pcisig.com/members/downloads/pcifw_r3_1_13Dec10.pdf */ const guid_t pci_acpi_dsm_guid = GUID_INIT(0xe5c937d0, 0x3553, 0x4d7a, 0x91, 0x17, 0xea, 0x4d, 0x19, 0xc3, 0x43, 0x4d); #if defined(CONFIG_PCI_QUIRKS) && defined(CONFIG_ARM64) static int acpi_get_rc_addr(struct acpi_device *adev, struct resource *res) { struct device *dev = &adev->dev; struct resource_entry *entry; struct list_head list; unsigned long flags; int ret; INIT_LIST_HEAD(&list); flags = IORESOURCE_MEM; ret = acpi_dev_get_resources(adev, &list, acpi_dev_filter_resource_type_cb, (void *) flags); if (ret < 0) { dev_err(dev, "failed to parse _CRS method, error code %d\n", ret); return ret; } if (ret == 0) { dev_err(dev, "no IO and memory resources present in _CRS\n"); return -EINVAL; } entry = list_first_entry(&list, struct resource_entry, node); *res = *entry->res; acpi_dev_free_resource_list(&list); return 0; } static acpi_status acpi_match_rc(acpi_handle handle, u32 lvl, void *context, void **retval) { u16 *segment = context; unsigned long long uid; acpi_status status; status = acpi_evaluate_integer(handle, "_UID", NULL, &uid); if (ACPI_FAILURE(status) || uid != *segment) return AE_CTRL_DEPTH; *(acpi_handle *)retval = handle; return AE_CTRL_TERMINATE; } int acpi_get_rc_resources(struct device *dev, const char *hid, u16 segment, struct resource *res) { struct acpi_device *adev; acpi_status status; acpi_handle handle; int ret; status = acpi_get_devices(hid, acpi_match_rc, &segment, &handle); if (ACPI_FAILURE(status)) { dev_err(dev, "can't find _HID %s device to locate resources\n", hid); return -ENODEV; } ret = acpi_bus_get_device(handle, &adev); if (ret) return ret; ret = acpi_get_rc_addr(adev, res); if (ret) { dev_err(dev, "can't get resource from %s\n", dev_name(&adev->dev)); return ret; } return 0; } #endif phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle) { acpi_status status = AE_NOT_EXIST; unsigned long long mcfg_addr; if (handle) status = acpi_evaluate_integer(handle, METHOD_NAME__CBA, NULL, &mcfg_addr); if (ACPI_FAILURE(status)) return 0; return (phys_addr_t)mcfg_addr; } static acpi_status decode_type0_hpx_record(union acpi_object *record, struct hotplug_params *hpx) { int i; union acpi_object *fields = record->package.elements; u32 revision = fields[1].integer.value; switch (revision) { case 1: if (record->package.count != 6) return AE_ERROR; for (i = 2; i < 6; i++) if (fields[i].type != ACPI_TYPE_INTEGER) return AE_ERROR; hpx->t0 = &hpx->type0_data; hpx->t0->revision = revision; hpx->t0->cache_line_size = fields[2].integer.value; hpx->t0->latency_timer = fields[3].integer.value; hpx->t0->enable_serr = fields[4].integer.value; hpx->t0->enable_perr = fields[5].integer.value; break; default: printk(KERN_WARNING "%s: Type 0 Revision %d record not supported\n", __func__, revision); return AE_ERROR; } return AE_OK; } static acpi_status decode_type1_hpx_record(union acpi_object *record, struct hotplug_params *hpx) { int i; union acpi_object *fields = record->package.elements; u32 revision = fields[1].integer.value; switch (revision) { case 1: if (record->package.count != 5) return AE_ERROR; for (i = 2; i < 5; i++) if (fields[i].type != ACPI_TYPE_INTEGER) return AE_ERROR; hpx->t1 = &hpx->type1_data; hpx->t1->revision = revision; hpx->t1->max_mem_read = fields[2].integer.value; hpx->t1->avg_max_split = fields[3].integer.value; hpx->t1->tot_max_split = fields[4].integer.value; break; default: printk(KERN_WARNING "%s: Type 1 Revision %d record not supported\n", __func__, revision); return AE_ERROR; } return AE_OK; } static acpi_status decode_type2_hpx_record(union acpi_object *record, struct hotplug_params *hpx) { int i; union acpi_object *fields = record->package.elements; u32 revision = fields[1].integer.value; switch (revision) { case 1: if (record->package.count != 18) return AE_ERROR; for (i = 2; i < 18; i++) if (fields[i].type != ACPI_TYPE_INTEGER) return AE_ERROR; hpx->t2 = &hpx->type2_data; hpx->t2->revision = revision; hpx->t2->unc_err_mask_and = fields[2].integer.value; hpx->t2->unc_err_mask_or = fields[3].integer.value; hpx->t2->unc_err_sever_and = fields[4].integer.value; hpx->t2->unc_err_sever_or = fields[5].integer.value; hpx->t2->cor_err_mask_and = fields[6].integer.value; hpx->t2->cor_err_mask_or = fields[7].integer.value; hpx->t2->adv_err_cap_and = fields[8].integer.value; hpx->t2->adv_err_cap_or = fields[9].integer.value; hpx->t2->pci_exp_devctl_and = fields[10].integer.value; hpx->t2->pci_exp_devctl_or = fields[11].integer.value; hpx->t2->pci_exp_lnkctl_and = fields[12].integer.value; hpx->t2->pci_exp_lnkctl_or = fields[13].integer.value; hpx->t2->sec_unc_err_sever_and = fields[14].integer.value; hpx->t2->sec_unc_err_sever_or = fields[15].integer.value; hpx->t2->sec_unc_err_mask_and = fields[16].integer.value; hpx->t2->sec_unc_err_mask_or = fields[17].integer.value; break; default: printk(KERN_WARNING "%s: Type 2 Revision %d record not supported\n", __func__, revision); return AE_ERROR; } return AE_OK; } static acpi_status acpi_run_hpx(acpi_handle handle, struct hotplug_params *hpx) { acpi_status status; struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; union acpi_object *package, *record, *fields; u32 type; int i; /* Clear the return buffer with zeros */ memset(hpx, 0, sizeof(struct hotplug_params)); status = acpi_evaluate_object(handle, "_HPX", NULL, &buffer); if (ACPI_FAILURE(status)) return status; package = (union acpi_object *)buffer.pointer; if (package->type != ACPI_TYPE_PACKAGE) { status = AE_ERROR; goto exit; } for (i = 0; i < package->package.count; i++) { record = &package->package.elements[i]; if (record->type != ACPI_TYPE_PACKAGE) { status = AE_ERROR; goto exit; } fields = record->package.elements; if (fields[0].type != ACPI_TYPE_INTEGER || fields[1].type != ACPI_TYPE_INTEGER) { status = AE_ERROR; goto exit; } type = fields[0].integer.value; switch (type) { case 0: status = decode_type0_hpx_record(record, hpx); if (ACPI_FAILURE(status)) goto exit; break; case 1: status = decode_type1_hpx_record(record, hpx); if (ACPI_FAILURE(status)) goto exit; break; case 2: status = decode_type2_hpx_record(record, hpx); if (ACPI_FAILURE(status)) goto exit; break; default: printk(KERN_ERR "%s: Type %d record not supported\n", __func__, type); status = AE_ERROR; goto exit; } } exit: kfree(buffer.pointer); return status; } static acpi_status acpi_run_hpp(acpi_handle handle, struct hotplug_params *hpp) { acpi_status status; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; union acpi_object *package, *fields; int i; memset(hpp, 0, sizeof(struct hotplug_params)); status = acpi_evaluate_object(handle, "_HPP", NULL, &buffer); if (ACPI_FAILURE(status)) return status; package = (union acpi_object *) buffer.pointer; if (package->type != ACPI_TYPE_PACKAGE || package->package.count != 4) { status = AE_ERROR; goto exit; } fields = package->package.elements; for (i = 0; i < 4; i++) { if (fields[i].type != ACPI_TYPE_INTEGER) { status = AE_ERROR; goto exit; } } hpp->t0 = &hpp->type0_data; hpp->t0->revision = 1; hpp->t0->cache_line_size = fields[0].integer.value; hpp->t0->latency_timer = fields[1].integer.value; hpp->t0->enable_serr = fields[2].integer.value; hpp->t0->enable_perr = fields[3].integer.value; exit: kfree(buffer.pointer); return status; } /* pci_get_hp_params * * @dev - the pci_dev for which we want parameters * @hpp - allocated by the caller */ int pci_get_hp_params(struct pci_dev *dev, struct hotplug_params *hpp) { acpi_status status; acpi_handle handle, phandle; struct pci_bus *pbus; if (acpi_pci_disabled) return -ENODEV; handle = NULL; for (pbus = dev->bus; pbus; pbus = pbus->parent) { handle = acpi_pci_get_bridge_handle(pbus); if (handle) break; } /* * _HPP settings apply to all child buses, until another _HPP is * encountered. If we don't find an _HPP for the input pci dev, * look for it in the parent device scope since that would apply to * this pci dev. */ while (handle) { status = acpi_run_hpx(handle, hpp); if (ACPI_SUCCESS(status)) return 0; status = acpi_run_hpp(handle, hpp); if (ACPI_SUCCESS(status)) return 0; if (acpi_is_root_bridge(handle)) break; status = acpi_get_parent(handle, &phandle); if (ACPI_FAILURE(status)) break; handle = phandle; } return -ENODEV; } /** * pciehp_is_native - Check whether a hotplug port is handled by the OS * @bridge: Hotplug port to check * * Returns true if the given @bridge is handled by the native PCIe hotplug * driver. */ bool pciehp_is_native(struct pci_dev *bridge) { const struct pci_host_bridge *host; u32 slot_cap; if (!IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE)) return false; pcie_capability_read_dword(bridge, PCI_EXP_SLTCAP, &slot_cap); if (!(slot_cap & PCI_EXP_SLTCAP_HPC)) return false; if (pcie_ports_native) return true; host = pci_find_host_bridge(bridge->bus); return host->native_pcie_hotplug; } /** * shpchp_is_native - Check whether a hotplug port is handled by the OS * @bridge: Hotplug port to check * * Returns true if the given @bridge is handled by the native SHPC hotplug * driver. */ bool shpchp_is_native(struct pci_dev *bridge) { return bridge->shpc_managed; } /** * pci_acpi_wake_bus - Root bus wakeup notification fork function. * @context: Device wakeup context. */ static void pci_acpi_wake_bus(struct acpi_device_wakeup_context *context) { struct acpi_device *adev; struct acpi_pci_root *root; adev = container_of(context, struct acpi_device, wakeup.context); root = acpi_driver_data(adev); pci_pme_wakeup_bus(root->bus); } /** * pci_acpi_wake_dev - PCI device wakeup notification work function. * @context: Device wakeup context. */ static void pci_acpi_wake_dev(struct acpi_device_wakeup_context *context) { struct pci_dev *pci_dev; pci_dev = to_pci_dev(context->dev); if (pci_dev->pme_poll) pci_dev->pme_poll = false; if (pci_dev->current_state == PCI_D3cold) { pci_wakeup_event(pci_dev); pm_request_resume(&pci_dev->dev); return; } /* Clear PME Status if set. */ if (pci_dev->pme_support) pci_check_pme_status(pci_dev); pci_wakeup_event(pci_dev); pm_request_resume(&pci_dev->dev); pci_pme_wakeup_bus(pci_dev->subordinate); } /** * pci_acpi_add_bus_pm_notifier - Register PM notifier for root PCI bus. * @dev: PCI root bridge ACPI device. */ acpi_status pci_acpi_add_bus_pm_notifier(struct acpi_device *dev) { return acpi_add_pm_notifier(dev, NULL, pci_acpi_wake_bus); } /** * pci_acpi_add_pm_notifier - Register PM notifier for given PCI device. * @dev: ACPI device to add the notifier for. * @pci_dev: PCI device to check for the PME status if an event is signaled. */ acpi_status pci_acpi_add_pm_notifier(struct acpi_device *dev, struct pci_dev *pci_dev) { return acpi_add_pm_notifier(dev, &pci_dev->dev, pci_acpi_wake_dev); } /* * _SxD returns the D-state with the highest power * (lowest D-state number) supported in the S-state "x". * * If the devices does not have a _PRW * (Power Resources for Wake) supporting system wakeup from "x" * then the OS is free to choose a lower power (higher number * D-state) than the return value from _SxD. * * But if _PRW is enabled at S-state "x", the OS * must not choose a power lower than _SxD -- * unless the device has an _SxW method specifying * the lowest power (highest D-state number) the device * may enter while still able to wake the system. * * ie. depending on global OS policy: * * if (_PRW at S-state x) * choose from highest power _SxD to lowest power _SxW * else // no _PRW at S-state x * choose highest power _SxD or any lower power */ static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev) { int acpi_state, d_max; if (pdev->no_d3cold) d_max = ACPI_STATE_D3_HOT; else d_max = ACPI_STATE_D3_COLD; acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL, d_max); if (acpi_state < 0) return PCI_POWER_ERROR; switch (acpi_state) { case ACPI_STATE_D0: return PCI_D0; case ACPI_STATE_D1: return PCI_D1; case ACPI_STATE_D2: return PCI_D2; case ACPI_STATE_D3_HOT: return PCI_D3hot; case ACPI_STATE_D3_COLD: return PCI_D3cold; } return PCI_POWER_ERROR; } static struct acpi_device *acpi_pci_find_companion(struct device *dev); static bool acpi_pci_bridge_d3(struct pci_dev *dev) { const struct fwnode_handle *fwnode; struct acpi_device *adev; struct pci_dev *root; u8 val; if (!dev->is_hotplug_bridge) return false; /* * Look for a special _DSD property for the root port and if it * is set we know the hierarchy behind it supports D3 just fine. */ root = pci_find_pcie_root_port(dev); if (!root) return false; adev = ACPI_COMPANION(&root->dev); if (root == dev) { /* * It is possible that the ACPI companion is not yet bound * for the root port so look it up manually here. */ if (!adev && !pci_dev_is_added(root)) adev = acpi_pci_find_companion(&root->dev); } if (!adev) return false; fwnode = acpi_fwnode_handle(adev); if (fwnode_property_read_u8(fwnode, "HotPlugSupportInD3", &val)) return false; return val == 1; } static bool acpi_pci_power_manageable(struct pci_dev *dev) { struct acpi_device *adev = ACPI_COMPANION(&dev->dev); return adev ? acpi_device_power_manageable(adev) : false; } static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state) { struct acpi_device *adev = ACPI_COMPANION(&dev->dev); static const u8 state_conv[] = { [PCI_D0] = ACPI_STATE_D0, [PCI_D1] = ACPI_STATE_D1, [PCI_D2] = ACPI_STATE_D2, [PCI_D3hot] = ACPI_STATE_D3_HOT, [PCI_D3cold] = ACPI_STATE_D3_COLD, }; int error = -EINVAL; /* If the ACPI device has _EJ0, ignore the device */ if (!adev || acpi_has_method(adev->handle, "_EJ0")) return -ENODEV; switch (state) { case PCI_D3cold: if (dev_pm_qos_flags(&dev->dev, PM_QOS_FLAG_NO_POWER_OFF) == PM_QOS_FLAGS_ALL) { error = -EBUSY; break; } /* Fall through */ case PCI_D0: case PCI_D1: case PCI_D2: case PCI_D3hot: error = acpi_device_set_power(adev, state_conv[state]); } if (!error) pci_dbg(dev, "power state changed by ACPI to %s\n", acpi_power_state_string(state_conv[state])); return error; } static pci_power_t acpi_pci_get_power_state(struct pci_dev *dev) { struct acpi_device *adev = ACPI_COMPANION(&dev->dev); static const pci_power_t state_conv[] = { [ACPI_STATE_D0] = PCI_D0, [ACPI_STATE_D1] = PCI_D1, [ACPI_STATE_D2] = PCI_D2, [ACPI_STATE_D3_HOT] = PCI_D3hot, [ACPI_STATE_D3_COLD] = PCI_D3cold, }; int state; if (!adev || !acpi_device_power_manageable(adev)) return PCI_UNKNOWN; if (acpi_device_get_power(adev, &state) || state == ACPI_STATE_UNKNOWN) return PCI_UNKNOWN; return state_conv[state]; } static int acpi_pci_propagate_wakeup(struct pci_bus *bus, bool enable) { while (bus->parent) { if (acpi_pm_device_can_wakeup(&bus->self->dev)) return acpi_pm_set_bridge_wakeup(&bus->self->dev, enable); bus = bus->parent; } /* We have reached the root bus. */ if (bus->bridge) { if (acpi_pm_device_can_wakeup(bus->bridge)) return acpi_pm_set_bridge_wakeup(bus->bridge, enable); } return 0; } static int acpi_pci_wakeup(struct pci_dev *dev, bool enable) { if (acpi_pm_device_can_wakeup(&dev->dev)) return acpi_pm_set_device_wakeup(&dev->dev, enable); return acpi_pci_propagate_wakeup(dev->bus, enable); } static bool acpi_pci_need_resume(struct pci_dev *dev) { struct acpi_device *adev = ACPI_COMPANION(&dev->dev); /* * In some cases (eg. Samsung 305V4A) leaving a bridge in suspend over * system-wide suspend/resume confuses the platform firmware, so avoid * doing that. According to Section 16.1.6 of ACPI 6.2, endpoint * devices are expected to be in D3 before invoking the S3 entry path * from the firmware, so they should not be affected by this issue. */ if (pci_is_bridge(dev) && acpi_target_system_state() != ACPI_STATE_S0) return true; if (!adev || !acpi_device_power_manageable(adev)) return false; if (device_may_wakeup(&dev->dev) != !!adev->wakeup.prepare_count) return true; if (acpi_target_system_state() == ACPI_STATE_S0) return false; return !!adev->power.flags.dsw_present; } static const struct pci_platform_pm_ops acpi_pci_platform_pm = { .bridge_d3 = acpi_pci_bridge_d3, .is_manageable = acpi_pci_power_manageable, .set_state = acpi_pci_set_power_state, .get_state = acpi_pci_get_power_state, .choose_state = acpi_pci_choose_state, .set_wakeup = acpi_pci_wakeup, .need_resume = acpi_pci_need_resume, }; void acpi_pci_add_bus(struct pci_bus *bus) { union acpi_object *obj; struct pci_host_bridge *bridge; if (acpi_pci_disabled || !bus->bridge || !ACPI_HANDLE(bus->bridge)) return; acpi_pci_slot_enumerate(bus); acpiphp_enumerate_slots(bus); /* * For a host bridge, check its _DSM for function 8 and if * that is available, mark it in pci_host_bridge. */ if (!pci_is_root_bus(bus)) return; obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 3, RESET_DELAY_DSM, NULL); if (!obj) return; if (obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 1) { bridge = pci_find_host_bridge(bus); bridge->ignore_reset_delay = 1; } ACPI_FREE(obj); } void acpi_pci_remove_bus(struct pci_bus *bus) { if (acpi_pci_disabled || !bus->bridge) return; acpiphp_remove_slots(bus); acpi_pci_slot_remove(bus); } /* ACPI bus type */ static struct acpi_device *acpi_pci_find_companion(struct device *dev) { struct pci_dev *pci_dev = to_pci_dev(dev); bool check_children; u64 addr; check_children = pci_is_bridge(pci_dev); /* Please ref to ACPI spec for the syntax of _ADR */ addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn); return acpi_find_child_device(ACPI_COMPANION(dev->parent), addr, check_children); } /** * pci_acpi_optimize_delay - optimize PCI D3 and D3cold delay from ACPI * @pdev: the PCI device whose delay is to be updated * @handle: ACPI handle of this device * * Update the d3_delay and d3cold_delay of a PCI device from the ACPI _DSM * control method of either the device itself or the PCI host bridge. * * Function 8, "Reset Delay," applies to the entire hierarchy below a PCI * host bridge. If it returns one, the OS may assume that all devices in * the hierarchy have already completed power-on reset delays. * * Function 9, "Device Readiness Durations," applies only to the object * where it is located. It returns delay durations required after various * events if the device requires less time than the spec requires. Delays * from this function take precedence over the Reset Delay function. * * These _DSM functions are defined by the draft ECN of January 28, 2014, * titled "ACPI additions for FW latency optimizations." */ static void pci_acpi_optimize_delay(struct pci_dev *pdev, acpi_handle handle) { struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus); int value; union acpi_object *obj, *elements; if (bridge->ignore_reset_delay) pdev->d3cold_delay = 0; obj = acpi_evaluate_dsm(handle, &pci_acpi_dsm_guid, 3, FUNCTION_DELAY_DSM, NULL); if (!obj) return; if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 5) { elements = obj->package.elements; if (elements[0].type == ACPI_TYPE_INTEGER) { value = (int)elements[0].integer.value / 1000; if (value < PCI_PM_D3COLD_WAIT) pdev->d3cold_delay = value; } if (elements[3].type == ACPI_TYPE_INTEGER) { value = (int)elements[3].integer.value / 1000; if (value < PCI_PM_D3_WAIT) pdev->d3_delay = value; } } ACPI_FREE(obj); } static void pci_acpi_set_untrusted(struct pci_dev *dev) { u8 val; if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT) return; if (device_property_read_u8(&dev->dev, "ExternalFacingPort", &val)) return; /* * These root ports expose PCIe (including DMA) outside of the * system so make sure we treat them and everything behind as * untrusted. */ if (val) dev->untrusted = 1; } static void pci_acpi_setup(struct device *dev) { struct pci_dev *pci_dev = to_pci_dev(dev); struct acpi_device *adev = ACPI_COMPANION(dev); if (!adev) return; pci_acpi_optimize_delay(pci_dev, adev->handle); pci_acpi_set_untrusted(pci_dev); pci_acpi_add_pm_notifier(adev, pci_dev); if (!adev->wakeup.flags.valid) return; device_set_wakeup_capable(dev, true); /* * For bridges that can do D3 we enable wake automatically (as * we do for the power management itself in that case). The * reason is that the bridge may have additional methods such as * _DSW that need to be called. */ if (pci_dev->bridge_d3) device_wakeup_enable(dev); acpi_pci_wakeup(pci_dev, false); } static void pci_acpi_cleanup(struct device *dev) { struct acpi_device *adev = ACPI_COMPANION(dev); struct pci_dev *pci_dev = to_pci_dev(dev); if (!adev) return; pci_acpi_remove_pm_notifier(adev); if (adev->wakeup.flags.valid) { if (pci_dev->bridge_d3) device_wakeup_disable(dev); device_set_wakeup_capable(dev, false); } } static bool pci_acpi_bus_match(struct device *dev) { return dev_is_pci(dev); } static struct acpi_bus_type acpi_pci_bus = { .name = "PCI", .match = pci_acpi_bus_match, .find_companion = acpi_pci_find_companion, .setup = pci_acpi_setup, .cleanup = pci_acpi_cleanup, }; static struct fwnode_handle *(*pci_msi_get_fwnode_cb)(struct device *dev); /** * pci_msi_register_fwnode_provider - Register callback to retrieve fwnode * @fn: Callback matching a device to a fwnode that identifies a PCI * MSI domain. * * This should be called by irqchip driver, which is the parent of * the MSI domain to provide callback interface to query fwnode. */ void pci_msi_register_fwnode_provider(struct fwnode_handle *(*fn)(struct device *)) { pci_msi_get_fwnode_cb = fn; } /** * pci_host_bridge_acpi_msi_domain - Retrieve MSI domain of a PCI host bridge * @bus: The PCI host bridge bus. * * This function uses the callback function registered by * pci_msi_register_fwnode_provider() to retrieve the irq_domain with * type DOMAIN_BUS_PCI_MSI of the specified host bridge bus. * This returns NULL on error or when the domain is not found. */ struct irq_domain *pci_host_bridge_acpi_msi_domain(struct pci_bus *bus) { struct fwnode_handle *fwnode; if (!pci_msi_get_fwnode_cb) return NULL; fwnode = pci_msi_get_fwnode_cb(&bus->dev); if (!fwnode) return NULL; return irq_find_matching_fwnode(fwnode, DOMAIN_BUS_PCI_MSI); } static int __init acpi_pci_init(void) { int ret; if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_MSI) { pr_info("ACPI FADT declares the system doesn't support MSI, so disable it\n"); pci_no_msi(); } if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) { pr_info("ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n"); pcie_no_aspm(); } ret = register_acpi_bus_type(&acpi_pci_bus); if (ret) return 0; pci_set_platform_pm(&acpi_pci_platform_pm); acpi_pci_slot_init(); acpiphp_init(); return 0; } arch_initcall(acpi_pci_init);