--- /dev/null
+/*
+ * acpi_processor.c - ACPI processor enumeration support
+ *
+ * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
+ * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
+ * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
+ * Copyright (C) 2013, Intel Corporation
+ * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ *
+ * 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 <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+
+#include <acpi/processor.h>
+
+#include <asm/cpu.h>
+
+#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 == PHYS_CPUID_INVALID)
+ 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);
+ phys_cpuid_t phys_id;
+ int 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 == PHYS_CPUID_INVALID)
+ 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");
+}
Code Review / kvmfornfv.git / blobdiff