[linux-block.git] / drivers / pci / pcie / aer / aerdrv.c

/*
 * 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"
#include "../../pci.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);
static void aer_remove(struct pcie_device *dev);
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);

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",
	.port_type	= PCIE_ANY_PORT,
	.service	= PCIE_PORT_SERVICE_AER,

	.probe		= aer_probe,
	.remove		= aer_remove,

	.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.
 **/
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_ext_capability(pdev->port, PCI_EXT_CAP_ID_ERR);
	/*
	 * 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;
}
EXPORT_SYMBOL_GPL(aer_irq);

/**
 * 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;

	rpc = kzalloc(sizeof(struct aer_rpc), GFP_KERNEL);
	if (!rpc)
		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)
{
	int status;
	struct aer_rpc *rpc;
	struct device *device = &dev->device;

	/* Init */
	status = aer_init(dev);
	if (status)
		return status;

	/* Alloc rpc data structure */
	rpc = aer_alloc_rpc(dev);
	if (!rpc) {
		dev_printk(KERN_DEBUG, device, "alloc rpc failed\n");
		aer_remove(dev);
		return -ENOMEM;
	}

	/* Request IRQ ISR */
	status = request_irq(dev->irq, aer_irq, IRQF_SHARED, "aerdrv", dev);
	if (status) {
		dev_printk(KERN_DEBUG, device, "request IRQ failed\n");
		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_ext_capability(dev, PCI_EXT_CAP_ID_ERR);

	/* 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);
	dev_printk(KERN_DEBUG, &dev->dev, "Root Port link has been reset\n");

	/* 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_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
	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;
	if (!pci_msi_enabled())
		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);
Commit	Line	Data
6c2b374d ZY	1	/*
	2	* drivers/pci/pcie/aer/aerdrv.c
	3	*
	4	* This file is subject to the terms and conditions of the GNU General Public
	5	* License. See the file "COPYING" in the main directory of this archive
	6	* for more details.
	7	*
	8	* This file implements the AER root port service driver. The driver will
	9	* register an irq handler. When root port triggers an AER interrupt, the irq
	10	* handler will collect root port status and schedule a work.
	11	*
	12	* Copyright (C) 2006 Intel Corp.
	13	* Tom Long Nguyen (tom.l.nguyen@intel.com)
	14	* Zhang Yanmin (yanmin.zhang@intel.com)
	15	*
	16	*/
	17
	18	#include <linux/module.h>
	19	#include <linux/pci.h>
	20	#include <linux/kernel.h>
	21	#include <linux/errno.h>
	22	#include <linux/pm.h>
	23	#include <linux/init.h>
	24	#include <linux/interrupt.h>
	25	#include <linux/delay.h>
	26	#include <linux/pcieport_if.h>
	27
	28	#include "aerdrv.h"
5d9526d0	29	#include "../../pci.h"
6c2b374d ZY	30
	31	/*
	32	* Version Information
	33	*/
	34	#define DRIVER_VERSION "v1.0"
	35	#define DRIVER_AUTHOR "tom.l.nguyen@intel.com"
	36	#define DRIVER_DESC "Root Port Advanced Error Reporting Driver"
	37	MODULE_AUTHOR(DRIVER_AUTHOR);
	38	MODULE_DESCRIPTION(DRIVER_DESC);
	39	MODULE_LICENSE("GPL");
	40
c9a91883	41	static int __devinit aer_probe(struct pcie_device *dev);
6c2b374d	42	static void aer_remove(struct pcie_device *dev);
6c2b374d ZY	43	static pci_ers_result_t aer_error_detected(struct pci_dev *dev,
	44	enum pci_channel_state error);
	45	static void aer_error_resume(struct pci_dev *dev);
	46	static pci_ers_result_t aer_root_reset(struct pci_dev *dev);
	47
6c2b374d ZY	48	static struct pci_error_handlers aer_error_handlers = {
6c2b374d ZY	49	.error_detected = aer_error_detected,
c9a91883	50	.resume = aer_error_resume,
6c2b374d ZY	51	};
6c2b374d ZY	52
c1996c27	53	static struct pcie_port_service_driver aerdriver = {
6c2b374d	54	.name = "aer",
22106368 RW	55	.port_type = PCIE_ANY_PORT,
22106368 RW	56	.service = PCIE_PORT_SERVICE_AER,
6c2b374d ZY	57
	58	.probe = aer_probe,
	59	.remove = aer_remove,
	60
6c2b374d ZY	61	.err_handler = &aer_error_handlers,
	62
	63	.reset_link = aer_root_reset,
	64	};
	65
7f785763 RD	66	static int pcie_aer_disable;
	67
	68	void pci_no_aer(void)
	69	{
	70	pcie_aer_disable = 1; /* has priority over 'forceload' */
	71	}
	72
6c2b374d ZY	73	/**
	74	* aer_irq - Root Port's ISR
	75	* @irq: IRQ assigned to Root Port
	76	* @context: pointer to Root Port data structure
6c2b374d ZY	77	*
	78	* Invoked when Root Port detects AER messages.
	79	**/
634deb02	80	irqreturn_t aer_irq(int irq, void *context)
6c2b374d ZY	81	{
	82	unsigned int status, id;
	83	struct pcie_device pdev = (struct pcie_device )context;
	84	struct aer_rpc *rpc = get_service_data(pdev);
	85	int next_prod_idx;
	86	unsigned long flags;
	87	int pos;
	88
0927678f	89	pos = pci_find_ext_capability(pdev->port, PCI_EXT_CAP_ID_ERR);
6c2b374d ZY	90	/*
	91	* Must lock access to Root Error Status Reg, Root Error ID Reg,
	92	* and Root error producer/consumer index
	93	*/
	94	spin_lock_irqsave(&rpc->e_lock, flags);
	95
	96	/* Read error status */
	97	pci_read_config_dword(pdev->port, pos + PCI_ERR_ROOT_STATUS, &status);
	98	if (!(status & ROOT_ERR_STATUS_MASKS)) {
	99	spin_unlock_irqrestore(&rpc->e_lock, flags);
	100	return IRQ_NONE;
	101	}
	102
	103	/* Read error source and clear error status */
	104	pci_read_config_dword(pdev->port, pos + PCI_ERR_ROOT_COR_SRC, &id);
	105	pci_write_config_dword(pdev->port, pos + PCI_ERR_ROOT_STATUS, status);
	106
	107	/* Store error source for later DPC handler */
	108	next_prod_idx = rpc->prod_idx + 1;
	109	if (next_prod_idx == AER_ERROR_SOURCES_MAX)
	110	next_prod_idx = 0;
	111	if (next_prod_idx == rpc->cons_idx) {
	112	/*
	113	* Error Storm Condition - possibly the same error occurred.
	114	* Drop the error.
	115	*/
	116	spin_unlock_irqrestore(&rpc->e_lock, flags);
	117	return IRQ_HANDLED;
	118	}
	119	rpc->e_sources[rpc->prod_idx].status = status;
	120	rpc->e_sources[rpc->prod_idx].id = id;
	121	rpc->prod_idx = next_prod_idx;
	122	spin_unlock_irqrestore(&rpc->e_lock, flags);
	123
	124	/* Invoke DPC handler */
	125	schedule_work(&rpc->dpc_handler);
	126
	127	return IRQ_HANDLED;
	128	}
634deb02	129	EXPORT_SYMBOL_GPL(aer_irq);
6c2b374d ZY	130
	131	/**
	132	* aer_alloc_rpc - allocate Root Port data structure
	133	* @dev: pointer to the pcie_dev data structure
	134	*
	135	* Invoked when Root Port's AER service is loaded.
	136	**/
c9a91883	137	static struct aer_rpc aer_alloc_rpc(struct pcie_device dev)
6c2b374d ZY	138	{
	139	struct aer_rpc *rpc;
	140
c9a91883 HS	141	rpc = kzalloc(sizeof(struct aer_rpc), GFP_KERNEL);
c9a91883 HS	142	if (!rpc)
6c2b374d ZY	143	return NULL;
6c2b374d ZY	144
6c2b374d ZY	145	/*
	146	* Initialize Root lock access, e_lock, to Root Error Status Reg,
	147	* Root Error ID Reg, and Root error producer/consumer index.
	148	*/
f5609d7e	149	spin_lock_init(&rpc->e_lock);
6c2b374d ZY	150
6c2b374d ZY	151	rpc->rpd = dev;
65f27f38	152	INIT_WORK(&rpc->dpc_handler, aer_isr);
6c2b374d ZY	153	rpc->prod_idx = rpc->cons_idx = 0;
	154	mutex_init(&rpc->rpc_mutex);
	155	init_waitqueue_head(&rpc->wait_release);
	156
	157	/* Use PCIE bus function to store rpc into PCIE device */
	158	set_service_data(dev, rpc);
	159
	160	return rpc;
	161	}
	162
	163	/**
	164	* aer_remove - clean up resources
	165	* @dev: pointer to the pcie_dev data structure
	166	*
	167	* Invoked when PCI Express bus unloads or AER probe fails.
	168	**/
	169	static void aer_remove(struct pcie_device *dev)
	170	{
	171	struct aer_rpc *rpc = get_service_data(dev);
	172
	173	if (rpc) {
	174	/* If register interrupt service, it must be free. */
	175	if (rpc->isr)
	176	free_irq(dev->irq, dev);
	177
	178	wait_event(rpc->wait_release, rpc->prod_idx == rpc->cons_idx);
	179
	180	aer_delete_rootport(rpc);
	181	set_service_data(dev, NULL);
	182	}
	183	}
	184
	185	/**
	186	* aer_probe - initialize resources
	187	* @dev: pointer to the pcie_dev data structure
	188	* @id: pointer to the service id data structure
	189	*
	190	* Invoked when PCI Express bus loads AER service driver.
	191	**/
c9a91883	192	static int __devinit aer_probe(struct pcie_device *dev)
6c2b374d ZY	193	{
	194	int status;
	195	struct aer_rpc *rpc;
	196	struct device *device = &dev->device;
	197
	198	/* Init */
c9a91883 HS	199	status = aer_init(dev);
c9a91883 HS	200	if (status)
6c2b374d ZY	201	return status;
	202
	203	/* Alloc rpc data structure */
c9a91883 HS	204	rpc = aer_alloc_rpc(dev);
c9a91883 HS	205	if (!rpc) {
531f254e	206	dev_printk(KERN_DEBUG, device, "alloc rpc failed\n");
6c2b374d ZY	207	aer_remove(dev);
	208	return -ENOMEM;
	209	}
	210
	211	/* Request IRQ ISR */
c9a91883 HS	212	status = request_irq(dev->irq, aer_irq, IRQF_SHARED, "aerdrv", dev);
c9a91883 HS	213	if (status) {
531f254e	214	dev_printk(KERN_DEBUG, device, "request IRQ failed\n");
6c2b374d ZY	215	aer_remove(dev);
	216	return status;
	217	}
	218
	219	rpc->isr = 1;
	220
	221	aer_enable_rootport(rpc);
	222
	223	return status;
	224	}
	225
	226	/**
	227	* aer_root_reset - reset link on Root Port
	228	* @dev: pointer to Root Port's pci_dev data structure
	229	*
	230	* Invoked by Port Bus driver when performing link reset at Root Port.
	231	**/
	232	static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
	233	{
	234	u16 p2p_ctrl;
	235	u32 status;
	236	int pos;
	237
0927678f	238	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
6c2b374d ZY	239
	240	/* Disable Root's interrupt in response to error messages */
	241	pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, 0);
	242
	243	/* Assert Secondary Bus Reset */
	244	pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &p2p_ctrl);
	245	p2p_ctrl \|= PCI_CB_BRIDGE_CTL_CB_RESET;
	246	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);
	247
	248	/* De-assert Secondary Bus Reset */
	249	p2p_ctrl &= ~PCI_CB_BRIDGE_CTL_CB_RESET;
	250	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);
	251
	252	/*
	253	* System software must wait for at least 100ms from the end
	254	* of a reset of one or more device before it is permitted
	255	* to issue Configuration Requests to those devices.
	256	*/
	257	msleep(200);
531f254e	258	dev_printk(KERN_DEBUG, &dev->dev, "Root Port link has been reset\n");
6c2b374d ZY	259
	260	/* Enable Root Port's interrupt in response to error messages */
	261	pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, &status);
	262	pci_write_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, status);
	263	pci_write_config_dword(dev,
	264	pos + PCI_ERR_ROOT_COMMAND,
	265	ROOT_PORT_INTR_ON_MESG_MASK);
	266
	267	return PCI_ERS_RESULT_RECOVERED;
	268	}
	269
	270	/**
	271	* aer_error_detected - update severity status
	272	* @dev: pointer to Root Port's pci_dev data structure
	273	* @error: error severity being notified by port bus
	274	*
	275	* Invoked by Port Bus driver during error recovery.
	276	**/
	277	static pci_ers_result_t aer_error_detected(struct pci_dev *dev,
	278	enum pci_channel_state error)
	279	{
	280	/* Root Port has no impact. Always recovers. */
	281	return PCI_ERS_RESULT_CAN_RECOVER;
	282	}
	283
	284	/**
	285	* aer_error_resume - clean up corresponding error status bits
	286	* @dev: pointer to Root Port's pci_dev data structure
	287	*
	288	* Invoked by Port Bus driver during nonfatal recovery.
	289	**/
	290	static void aer_error_resume(struct pci_dev *dev)
	291	{
	292	int pos;
	293	u32 status, mask;
	294	u16 reg16;
	295
	296	/* Clean up Root device status */
	297	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
	298	pci_read_config_word(dev, pos + PCI_EXP_DEVSTA, &reg16);
	299	pci_write_config_word(dev, pos + PCI_EXP_DEVSTA, reg16);
	300
	301	/* Clean AER Root Error Status */
0927678f	302	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
6c2b374d ZY	303	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, &status);
	304	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &mask);
	305	if (dev->error_state == pci_channel_io_normal)
	306	status &= ~mask; /* Clear corresponding nonfatal bits */
	307	else
	308	status &= mask; /* Clear corresponding fatal bits */
	309	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, status);
	310	}
	311
	312	/**
	313	* aer_service_init - register AER root service driver
	314	*
	315	* Invoked when AER root service driver is loaded.
	316	**/
	317	static int __init aer_service_init(void)
	318	{
7f785763 RD	319	if (pcie_aer_disable)
7f785763 RD	320	return -ENXIO;
3e77a3f7 AK	321	if (!pci_msi_enabled())
3e77a3f7 AK	322	return -ENXIO;
c1996c27	323	return pcie_port_service_register(&aerdriver);
6c2b374d ZY	324	}
	325
	326	/**
	327	* aer_service_exit - unregister AER root service driver
	328	*
	329	* Invoked when AER root service driver is unloaded.
	330	**/
	331	static void __exit aer_service_exit(void)
	332	{
c1996c27	333	pcie_port_service_unregister(&aerdriver);
6c2b374d ZY	334	}
	335
	336	module_init(aer_service_init);
	337	module_exit(aer_service_exit);