/* * 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_CPUstatic int acpi_processor_hotadd_init(struct acpi_processor *pr){	unsigned long long sta;	acpi_status status;	int ret; 	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_lsapic(pr->handle, pr->apic_id, &pr->id);	if (ret)		goto out; 	ret = arch_register_cpu(pr->id);	if (ret) {		acpi_unmap_lsapic(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;}#elsestatic 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 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;	}	pr->apic_id = acpi_get_apicid(pr->handle, device_declaration,					pr->acpi_id);	cpu_index = acpi_map_cpuid(pr->apic_id, pr->acpi_id); 	/* Handle UP system running SMP kernel, with no LAPIC in MADT */	if (!cpu0_initialized && (cpu_index == -1) &&	    (num_online_cpus() == 1)) {		cpu_index = 0;	} 	cpu0_initialized = 1; 	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, pr->handle);	if (result)		goto err; 	pr->dev = dev;	dev->offline = pr->flags.need_hotplug_init; 	/* 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_lsapic(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");}