/* * drivers/pci/pcie/aer/aerdrv.c * * This file is subject to the terms and conditions of the GNU General Public * License.  See the file "COPYING" in the main directory of this archive * for more details. * * This file implements the AER root port service driver. The driver will * register an irq handler. When root port triggers an AER interrupt, the irq * handler will collect root port status and schedule a work. * * Copyright (C) 2006 Intel Corp. *	Tom Long Nguyen (tom.l.nguyen@intel.com) *	Zhang Yanmin (yanmin.zhang@intel.com) * */#include <linux/module.h>#include <linux/pci.h>#include <linux/kernel.h>#include <linux/errno.h>#include <linux/pm.h>#include <linux/init.h>#include <linux/interrupt.h>#include <linux/delay.h>#include <linux/pcieport_if.h>#include "aerdrv.h"/* * Version Information */#define DRIVER_VERSION "v1.0"#define DRIVER_AUTHOR "tom.l.nguyen@intel.com"#define DRIVER_DESC "Root Port Advanced Error Reporting Driver"MODULE_AUTHOR(DRIVER_AUTHOR);MODULE_DESCRIPTION(DRIVER_DESC);MODULE_LICENSE("GPL");static int __devinit aer_probe (struct pcie_device *dev,	const struct pcie_port_service_id *id );static void aer_remove(struct pcie_device *dev);static int aer_suspend(struct pcie_device *dev, pm_message_t state){return 0;}static int aer_resume(struct pcie_device *dev) {return 0;}static pci_ers_result_t aer_error_detected(struct pci_dev *dev,	enum pci_channel_state error);static void aer_error_resume(struct pci_dev *dev);static pci_ers_result_t aer_root_reset(struct pci_dev *dev);/* * PCI Express bus's AER Root service driver data structure */static struct pcie_port_service_id aer_id[] = {	{	.vendor 	= PCI_ANY_ID,	.device 	= PCI_ANY_ID,	.port_type 	= PCIE_RC_PORT,	.service_type 	= PCIE_PORT_SERVICE_AER,	},	{ /* end: all zeroes */ }};static struct pci_error_handlers aer_error_handlers = {	.error_detected = aer_error_detected,	.resume = aer_error_resume,};static struct pcie_port_service_driver aerdriver = {	.name		= "aer",	.id_table	= &aer_id[0],	.probe		= aer_probe,	.remove		= aer_remove,	.suspend	= aer_suspend,	.resume		= aer_resume,	.err_handler	= &aer_error_handlers,	.reset_link	= aer_root_reset,};static int pcie_aer_disable;void pci_no_aer(void){	pcie_aer_disable = 1;	/* has priority over 'forceload' */}/** * aer_irq - Root Port's ISR * @irq: IRQ assigned to Root Port * @context: pointer to Root Port data structure * * Invoked when Root Port detects AER messages. **/static irqreturn_t aer_irq(int irq, void *context){	unsigned int status, id;	struct pcie_device *pdev = (struct pcie_device *)context;	struct aer_rpc *rpc = get_service_data(pdev);	int next_prod_idx;	unsigned long flags;	int pos;	pos = pci_find_aer_capability(pdev->port);	/*	 * Must lock access to Root Error Status Reg, Root Error ID Reg,	 * and Root error producer/consumer index	 */	spin_lock_irqsave(&rpc->e_lock, flags);	/* Read error status */	pci_read_config_dword(pdev->port, pos + PCI_ERR_ROOT_STATUS, &status);	if (!(status & ROOT_ERR_STATUS_MASKS)) {		spin_unlock_irqrestore(&rpc->e_lock, flags);		return IRQ_NONE;	}	/* Read error source and clear error status */	pci_read_config_dword(pdev->port, pos + PCI_ERR_ROOT_COR_SRC, &id);	pci_write_config_dword(pdev->port, pos + PCI_ERR_ROOT_STATUS, status);	/* Store error source for later DPC handler */	next_prod_idx = rpc->prod_idx + 1;	if (next_prod_idx == AER_ERROR_SOURCES_MAX)		next_prod_idx = 0;	if (next_prod_idx == rpc->cons_idx) {		/*		 * Error Storm Condition - possibly the same error occurred.		 * Drop the error.		 */		spin_unlock_irqrestore(&rpc->e_lock, flags);		return IRQ_HANDLED;	}	rpc->e_sources[rpc->prod_idx].status =  status;	rpc->e_sources[rpc->prod_idx].id = id;	rpc->prod_idx = next_prod_idx;	spin_unlock_irqrestore(&rpc->e_lock, flags);	/*  Invoke DPC handler */	schedule_work(&rpc->dpc_handler);	return IRQ_HANDLED;}/** * aer_alloc_rpc - allocate Root Port data structure * @dev: pointer to the pcie_dev data structure * * Invoked when Root Port's AER service is loaded. **/static struct aer_rpc* aer_alloc_rpc(struct pcie_device *dev){	struct aer_rpc *rpc;	if (!(rpc = kzalloc(sizeof(struct aer_rpc),		GFP_KERNEL)))		return NULL;	/*	 * Initialize Root lock access, e_lock, to Root Error Status Reg,	 * Root Error ID Reg, and Root error producer/consumer index.	 */	spin_lock_init(&rpc->e_lock);	rpc->rpd = dev;	INIT_WORK(&rpc->dpc_handler, aer_isr);	rpc->prod_idx = rpc->cons_idx = 0;	mutex_init(&rpc->rpc_mutex);	init_waitqueue_head(&rpc->wait_release);	/* Use PCIE bus function to store rpc into PCIE device */	set_service_data(dev, rpc);	return rpc;}/** * aer_remove - clean up resources * @dev: pointer to the pcie_dev data structure * * Invoked when PCI Express bus unloads or AER probe fails. **/static void aer_remove(struct pcie_device *dev){	struct aer_rpc *rpc = get_service_data(dev);	if (rpc) {		/* If register interrupt service, it must be free. */		if (rpc->isr)			free_irq(dev->irq, dev);		wait_event(rpc->wait_release, rpc->prod_idx == rpc->cons_idx);		aer_delete_rootport(rpc);		set_service_data(dev, NULL);	}}/** * aer_probe - initialize resources * @dev: pointer to the pcie_dev data structure * @id: pointer to the service id data structure * * Invoked when PCI Express bus loads AER service driver. **/static int __devinit aer_probe (struct pcie_device *dev,				const struct pcie_port_service_id *id ){	int status;	struct aer_rpc *rpc;	struct device *device = &dev->device;	/* Init */	if ((status = aer_init(dev)))		return status;	/* Alloc rpc data structure */	if (!(rpc = aer_alloc_rpc(dev))) {		printk(KERN_DEBUG "%s: Alloc rpc fails on PCIE device[%s]\n",			__FUNCTION__, device->bus_id);		aer_remove(dev);		return -ENOMEM;	}	/* Request IRQ ISR */	if ((status = request_irq(dev->irq, aer_irq, IRQF_SHARED, "aerdrv",				dev))) {		printk(KERN_DEBUG "%s: Request ISR fails on PCIE device[%s]\n",			__FUNCTION__, device->bus_id);		aer_remove(dev);		return status;	}	rpc->isr = 1;	aer_enable_rootport(rpc);	return status;}/** * aer_root_reset - reset link on Root Port * @dev: pointer to Root Port's pci_dev data structure * * Invoked by Port Bus driver when performing link reset at Root Port. **/static pci_ers_result_t aer_root_reset(struct pci_dev *dev){	u16 p2p_ctrl;	u32 status;	int pos;	pos = pci_find_aer_capability(dev);	/* Disable Root's interrupt in response to error messages */	pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, 0);	/* Assert Secondary Bus Reset */	pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &p2p_ctrl);	p2p_ctrl |= PCI_CB_BRIDGE_CTL_CB_RESET;	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);	/* De-assert Secondary Bus Reset */	p2p_ctrl &= ~PCI_CB_BRIDGE_CTL_CB_RESET;	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);	/*	 * System software must wait for at least 100ms from the end	 * of a reset of one or more device before it is permitted	 * to issue Configuration Requests to those devices.	 */	msleep(200);	printk(KERN_DEBUG "Complete link reset at Root[%s]\n", dev->dev.bus_id);	/* Enable Root Port's interrupt in response to error messages */	pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, &status);	pci_write_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, status);	pci_write_config_dword(dev,		pos + PCI_ERR_ROOT_COMMAND,		ROOT_PORT_INTR_ON_MESG_MASK);	return PCI_ERS_RESULT_RECOVERED;}/** * aer_error_detected - update severity status * @dev: pointer to Root Port's pci_dev data structure * @error: error severity being notified by port bus * * Invoked by Port Bus driver during error recovery. **/static pci_ers_result_t aer_error_detected(struct pci_dev *dev,			enum pci_channel_state error){	/* Root Port has no impact. Always recovers. */	return PCI_ERS_RESULT_CAN_RECOVER;}/** * aer_error_resume - clean up corresponding error status bits * @dev: pointer to Root Port's pci_dev data structure * * Invoked by Port Bus driver during nonfatal recovery. **/static void aer_error_resume(struct pci_dev *dev){	int pos;	u32 status, mask;	u16 reg16;	/* Clean up Root device status */	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);	pci_read_config_word(dev, pos + PCI_EXP_DEVSTA, &reg16);	pci_write_config_word(dev, pos + PCI_EXP_DEVSTA, reg16);	/* Clean AER Root Error Status */	pos = pci_find_aer_capability(dev);	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, &status);	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &mask);	if (dev->error_state == pci_channel_io_normal)		status &= ~mask; /* Clear corresponding nonfatal bits */	else		status &= mask; /* Clear corresponding fatal bits */	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, status);}/** * aer_service_init - register AER root service driver * * Invoked when AER root service driver is loaded. **/static int __init aer_service_init(void){	if (pcie_aer_disable)		return -ENXIO;	return pcie_port_service_register(&aerdriver);}/** * aer_service_exit - unregister AER root service driver * * Invoked when AER root service driver is unloaded. **/static void __exit aer_service_exit(void){	pcie_port_service_unregister(&aerdriver);}module_init(aer_service_init);module_exit(aer_service_exit);