/* * acpi_processor.c - ACPI processor enumeration support * * Copyright (C) 2001, 2002 Andy Grover * Copyright (C) 2001, 2002 Paul Diefenbaugh * Copyright (C) 2004 Dominik Brodowski * Copyright (C) 2004 Anil S Keshavamurthy * Copyright (C) 2013, Intel Corporation * Rafael J. Wysocki * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published * by the Free Software Foundation. */ #include #include #include #include #include #include #include #include "internal.h" #define _COMPONENT ACPI_PROCESSOR_COMPONENT ACPI_MODULE_NAME("processor"); DEFINE_PER_CPU(struct acpi_processor *, processors); EXPORT_PER_CPU_SYMBOL(processors); /* -------------------------------------------------------------------------- Errata Handling -------------------------------------------------------------------------- */ struct acpi_processor_errata errata __read_mostly; EXPORT_SYMBOL_GPL(errata); static int acpi_processor_errata_piix4(struct pci_dev *dev) { u8 value1 = 0; u8 value2 = 0; if (!dev) return -EINVAL; /* * Note that 'dev' references the PIIX4 ACPI Controller. */ switch (dev->revision) { case 0: ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n")); break; case 1: ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n")); break; case 2: ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n")); break; case 3: ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n")); break; default: ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n")); break; } switch (dev->revision) { case 0: /* PIIX4 A-step */ case 1: /* PIIX4 B-step */ /* * See specification changes #13 ("Manual Throttle Duty Cycle") * and #14 ("Enabling and Disabling Manual Throttle"), plus * erratum #5 ("STPCLK# Deassertion Time") from the January * 2002 PIIX4 specification update. Applies to only older * PIIX4 models. */ errata.piix4.throttle = 1; case 2: /* PIIX4E */ case 3: /* PIIX4M */ /* * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA * Livelock") from the January 2002 PIIX4 specification update. * Applies to all PIIX4 models. */ /* * BM-IDE * ------ * Find the PIIX4 IDE Controller and get the Bus Master IDE * Status register address. We'll use this later to read * each IDE controller's DMA status to make sure we catch all * DMA activity. */ dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB, PCI_ANY_ID, PCI_ANY_ID, NULL); if (dev) { errata.piix4.bmisx = pci_resource_start(dev, 4); pci_dev_put(dev); } /* * Type-F DMA * ---------- * Find the PIIX4 ISA Controller and read the Motherboard * DMA controller's status to see if Type-F (Fast) DMA mode * is enabled (bit 7) on either channel. Note that we'll * disable C3 support if this is enabled, as some legacy * devices won't operate well if fast DMA is disabled. */ dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_0, PCI_ANY_ID, PCI_ANY_ID, NULL); if (dev) { pci_read_config_byte(dev, 0x76, &value1); pci_read_config_byte(dev, 0x77, &value2); if ((value1 & 0x80) || (value2 & 0x80)) errata.piix4.fdma = 1; pci_dev_put(dev); } break; } if (errata.piix4.bmisx) ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Bus master activity detection (BM-IDE) erratum enabled\n")); if (errata.piix4.fdma) ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Type-F DMA livelock erratum (C3 disabled)\n")); return 0; } static int acpi_processor_errata(void) { int result = 0; struct pci_dev *dev = NULL; /* * PIIX4 */ dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID, PCI_ANY_ID, NULL); if (dev) { result = acpi_processor_errata_piix4(dev); pci_dev_put(dev); } return result; } /* -------------------------------------------------------------------------- Initialization -------------------------------------------------------------------------- */ #ifdef CONFIG_ACPI_HOTPLUG_CPU static int acpi_processor_hotadd_init(struct acpi_processor *pr) { unsigned long long sta; acpi_status status; int ret; if (pr->phys_id == -1) return -ENODEV; status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta); if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT)) return -ENODEV; cpu_maps_update_begin(); cpu_hotplug_begin(); ret = acpi_map_cpu(pr->handle, pr->phys_id, &pr->id); if (ret) goto out; ret = arch_register_cpu(pr->id); if (ret) { acpi_unmap_cpu(pr->id); goto out; } /* * CPU got hot-added, but cpu_data is not initialized yet. Set a flag * to delay cpu_idle/throttling initialization and do it when the CPU * gets online for the first time. */ pr_info("CPU%d has been hot-added\n", pr->id); pr->flags.need_hotplug_init = 1; out: cpu_hotplug_done(); cpu_maps_update_done(); return ret; } #else static inline int acpi_processor_hotadd_init(struct acpi_processor *pr) { return -ENODEV; } #endif /* CONFIG_ACPI_HOTPLUG_CPU */ static int acpi_processor_get_info(struct acpi_device *device) { union acpi_object object = { 0 }; struct acpi_buffer buffer = { sizeof(union acpi_object), &object }; struct acpi_processor *pr = acpi_driver_data(device); int phys_id, cpu_index, device_declaration = 0; acpi_status status = AE_OK; static int cpu0_initialized; unsigned long long value; acpi_processor_errata(); /* * Check to see if we have bus mastering arbitration control. This * is required for proper C3 usage (to maintain cache coherency). */ if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) { pr->flags.bm_control = 1; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Bus mastering arbitration control present\n")); } else ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No bus mastering arbitration control\n")); if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) { /* Declared with "Processor" statement; match ProcessorID */ status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer); if (ACPI_FAILURE(status)) { dev_err(&device->dev, "Failed to evaluate processor object (0x%x)\n", status); return -ENODEV; } pr->acpi_id = object.processor.proc_id; } else { /* * Declared with "Device" statement; match _UID. * Note that we don't handle string _UIDs yet. */ status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID, NULL, &value); if (ACPI_FAILURE(status)) { dev_err(&device->dev, "Failed to evaluate processor _UID (0x%x)\n", status); return -ENODEV; } device_declaration = 1; pr->acpi_id = value; } phys_id = acpi_get_phys_id(pr->handle, device_declaration, pr->acpi_id); if (phys_id < 0) acpi_handle_debug(pr->handle, "failed to get CPU physical ID.\n"); pr->phys_id = phys_id; cpu_index = acpi_map_cpuid(pr->phys_id, pr->acpi_id); if (!cpu0_initialized && !acpi_has_cpu_in_madt()) { cpu0_initialized = 1; /* * Handle UP system running SMP kernel, with no CPU * entry in MADT */ if ((cpu_index == -1) && (num_online_cpus() == 1)) cpu_index = 0; } pr->id = cpu_index; /* * Extra Processor objects may be enumerated on MP systems with * less than the max # of CPUs. They should be ignored _iff * they are physically not present. */ if (pr->id == -1) { int ret = acpi_processor_hotadd_init(pr); if (ret) return ret; } /* * On some boxes several processors use the same processor bus id. * But they are located in different scope. For example: * \_SB.SCK0.CPU0 * \_SB.SCK1.CPU0 * Rename the processor device bus id. And the new bus id will be * generated as the following format: * CPU+CPU ID. */ sprintf(acpi_device_bid(device), "CPU%X", pr->id); ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id, pr->acpi_id)); if (!object.processor.pblk_address) ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n")); else if (object.processor.pblk_length != 6) dev_err(&device->dev, "Invalid PBLK length [%d]\n", object.processor.pblk_length); else { pr->throttling.address = object.processor.pblk_address; pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset; pr->throttling.duty_width = acpi_gbl_FADT.duty_width; pr->pblk = object.processor.pblk_address; /* * We don't care about error returns - we just try to mark * these reserved so that nobody else is confused into thinking * that this region might be unused.. * * (In particular, allocating the IO range for Cardbus) */ request_region(pr->throttling.address, 6, "ACPI CPU throttle"); } /* * If ACPI describes a slot number for this CPU, we can use it to * ensure we get the right value in the "physical id" field * of /proc/cpuinfo */ status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value); if (ACPI_SUCCESS(status)) arch_fix_phys_package_id(pr->id, value); return 0; } /* * Do not put anything in here which needs the core to be online. * For example MSR access or setting up things which check for cpuinfo_x86 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc. * Such things have to be put in and set up by the processor driver's .probe(). */ static DEFINE_PER_CPU(void *, processor_device_array); static int acpi_processor_add(struct acpi_device *device, const struct acpi_device_id *id) { struct acpi_processor *pr; struct device *dev; int result = 0; pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL); if (!pr) return -ENOMEM; if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) { result = -ENOMEM; goto err_free_pr; } pr->handle = device->handle; strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME); strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS); device->driver_data = pr; result = acpi_processor_get_info(device); if (result) /* Processor is not physically present or unavailable */ return 0; #ifdef CONFIG_SMP if (pr->id >= setup_max_cpus && pr->id != 0) return 0; #endif BUG_ON(pr->id >= nr_cpu_ids); /* * Buggy BIOS check. * ACPI id of processors can be reported wrongly by the BIOS. * Don't trust it blindly */ if (per_cpu(processor_device_array, pr->id) != NULL && per_cpu(processor_device_array, pr->id) != device) { dev_warn(&device->dev, "BIOS reported wrong ACPI id %d for the processor\n", pr->id); /* Give up, but do not abort the namespace scan. */ goto err; } /* * processor_device_array is not cleared on errors to allow buggy BIOS * checks. */ per_cpu(processor_device_array, pr->id) = device; per_cpu(processors, pr->id) = pr; dev = get_cpu_device(pr->id); if (!dev) { result = -ENODEV; goto err; } result = acpi_bind_one(dev, device); if (result) goto err; pr->dev = dev; /* Trigger the processor driver's .probe() if present. */ if (device_attach(dev) >= 0) return 1; dev_err(dev, "Processor driver could not be attached\n"); acpi_unbind_one(dev); err: free_cpumask_var(pr->throttling.shared_cpu_map); device->driver_data = NULL; per_cpu(processors, pr->id) = NULL; err_free_pr: kfree(pr); return result; } #ifdef CONFIG_ACPI_HOTPLUG_CPU /* -------------------------------------------------------------------------- Removal -------------------------------------------------------------------------- */ static void acpi_processor_remove(struct acpi_device *device) { struct acpi_processor *pr; if (!device || !acpi_driver_data(device)) return; pr = acpi_driver_data(device); if (pr->id >= nr_cpu_ids) goto out; /* * The only reason why we ever get here is CPU hot-removal. The CPU is * already offline and the ACPI device removal locking prevents it from * being put back online at this point. * * Unbind the driver from the processor device and detach it from the * ACPI companion object. */ device_release_driver(pr->dev); acpi_unbind_one(pr->dev); /* Clean up. */ per_cpu(processor_device_array, pr->id) = NULL; per_cpu(processors, pr->id) = NULL; cpu_maps_update_begin(); cpu_hotplug_begin(); /* Remove the CPU. */ arch_unregister_cpu(pr->id); acpi_unmap_cpu(pr->id); cpu_hotplug_done(); cpu_maps_update_done(); try_offline_node(cpu_to_node(pr->id)); out: free_cpumask_var(pr->throttling.shared_cpu_map); kfree(pr); } #endif /* CONFIG_ACPI_HOTPLUG_CPU */ /* * The following ACPI IDs are known to be suitable for representing as * processor devices. */ static const struct acpi_device_id processor_device_ids[] = { { ACPI_PROCESSOR_OBJECT_HID, }, { ACPI_PROCESSOR_DEVICE_HID, }, { } }; static struct acpi_scan_handler __refdata processor_handler = { .ids = processor_device_ids, .attach = acpi_processor_add, #ifdef CONFIG_ACPI_HOTPLUG_CPU .detach = acpi_processor_remove, #endif .hotplug = { .enabled = true, }, }; void __init acpi_processor_init(void) { acpi_scan_add_handler_with_hotplug(&processor_handler, "processor"); }