[net-next-2.6.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"

/*
 * 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 aerdrv = {
	.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,
};

/**
 * 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 = (struct aer_rpc *)kmalloc(sizeof(struct aer_rpc),
		GFP_KERNEL)))
		return NULL;

	memset(rpc, 0, sizeof(struct aer_rpc));
	/*
	 * Initialize Root lock access, e_lock, to Root Error Status Reg,
	 * Root Error ID Reg, and Root error producer/consumer index.
	 */
	rpc->e_lock = SPIN_LOCK_UNLOCKED;

	rpc->rpd = dev;
	INIT_WORK(&rpc->dpc_handler, aer_isr, (void *)dev);
	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, SA_SHIRQ, "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)
{
	return pcie_port_service_register(&aerdrv);
}

/**
 * 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(&aerdrv);
}

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"
	29
	30	/*
	31	* Version Information
	32	*/
	33	#define DRIVER_VERSION "v1.0"
	34	#define DRIVER_AUTHOR "tom.l.nguyen@intel.com"
	35	#define DRIVER_DESC "Root Port Advanced Error Reporting Driver"
	36	MODULE_AUTHOR(DRIVER_AUTHOR);
	37	MODULE_DESCRIPTION(DRIVER_DESC);
	38	MODULE_LICENSE("GPL");
	39
	40	static int __devinit aer_probe (struct pcie_device *dev,
	41	const struct pcie_port_service_id *id );
	42	static void aer_remove(struct pcie_device *dev);
	43	static int aer_suspend(struct pcie_device *dev, pm_message_t state)
	44	{return 0;}
	45	static int aer_resume(struct pcie_device *dev) {return 0;}
	46	static pci_ers_result_t aer_error_detected(struct pci_dev *dev,
	47	enum pci_channel_state error);
	48	static void aer_error_resume(struct pci_dev *dev);
	49	static pci_ers_result_t aer_root_reset(struct pci_dev *dev);
	50
	51	/*
	52	* PCI Express bus's AER Root service driver data structure
	53	*/
	54	static struct pcie_port_service_id aer_id[] = {
	55	{
	56	.vendor = PCI_ANY_ID,
	57	.device = PCI_ANY_ID,
	58	.port_type = PCIE_RC_PORT,
	59	.service_type = PCIE_PORT_SERVICE_AER,
	60	},
	61	{ /* end: all zeroes */ }
	62	};
	63
	64	static struct pci_error_handlers aer_error_handlers = {
65	.error_detected = aer_error_detected,
66	.resume = aer_error_resume,
67	};
68
69	static struct pcie_port_service_driver aerdrv = {
70	.name = "aer",
71	.id_table = &aer_id[0],
72
73	.probe = aer_probe,
74	.remove = aer_remove,
75
76	.suspend = aer_suspend,
77	.resume = aer_resume,
78
79	.err_handler = &aer_error_handlers,
80
81	.reset_link = aer_root_reset,
82	};
83
84	/**
85	* aer_irq - Root Port's ISR
86	* @irq: IRQ assigned to Root Port
87	* @context: pointer to Root Port data structure
6c2b374d ZY	88	*
	89	* Invoked when Root Port detects AER messages.
	90	**/
7d12e780	91	static irqreturn_t aer_irq(int irq, void *context)
6c2b374d ZY	92	{
	93	unsigned int status, id;
	94	struct pcie_device pdev = (struct pcie_device )context;
	95	struct aer_rpc *rpc = get_service_data(pdev);
	96	int next_prod_idx;
	97	unsigned long flags;
	98	int pos;
	99
	100	pos = pci_find_aer_capability(pdev->port);
	101	/*
	102	* Must lock access to Root Error Status Reg, Root Error ID Reg,
	103	* and Root error producer/consumer index
	104	*/
	105	spin_lock_irqsave(&rpc->e_lock, flags);
	106
	107	/* Read error status */
	108	pci_read_config_dword(pdev->port, pos + PCI_ERR_ROOT_STATUS, &status);
	109	if (!(status & ROOT_ERR_STATUS_MASKS)) {
	110	spin_unlock_irqrestore(&rpc->e_lock, flags);
	111	return IRQ_NONE;
	112	}
	113
	114	/* Read error source and clear error status */
	115	pci_read_config_dword(pdev->port, pos + PCI_ERR_ROOT_COR_SRC, &id);
	116	pci_write_config_dword(pdev->port, pos + PCI_ERR_ROOT_STATUS, status);
	117
	118	/* Store error source for later DPC handler */
	119	next_prod_idx = rpc->prod_idx + 1;
	120	if (next_prod_idx == AER_ERROR_SOURCES_MAX)
	121	next_prod_idx = 0;
	122	if (next_prod_idx == rpc->cons_idx) {
	123	/*
	124	* Error Storm Condition - possibly the same error occurred.
	125	* Drop the error.
	126	*/
	127	spin_unlock_irqrestore(&rpc->e_lock, flags);
	128	return IRQ_HANDLED;
	129	}
	130	rpc->e_sources[rpc->prod_idx].status = status;
	131	rpc->e_sources[rpc->prod_idx].id = id;
	132	rpc->prod_idx = next_prod_idx;
	133	spin_unlock_irqrestore(&rpc->e_lock, flags);
	134
	135	/* Invoke DPC handler */
	136	schedule_work(&rpc->dpc_handler);
	137
	138	return IRQ_HANDLED;
	139	}
	140
	141	/**
	142	* aer_alloc_rpc - allocate Root Port data structure
	143	* @dev: pointer to the pcie_dev data structure
	144	*
	145	* Invoked when Root Port's AER service is loaded.
	146	**/
	147	static struct aer_rpc* aer_alloc_rpc(struct pcie_device *dev)
	148	{
	149	struct aer_rpc *rpc;
	150
	151	if (!(rpc = (struct aer_rpc *)kmalloc(sizeof(struct aer_rpc),
	152	GFP_KERNEL)))
	153	return NULL;
	154
	155	memset(rpc, 0, sizeof(struct aer_rpc));
156	/*
157	* Initialize Root lock access, e_lock, to Root Error Status Reg,
158	* Root Error ID Reg, and Root error producer/consumer index.
159	*/
160	rpc->e_lock = SPIN_LOCK_UNLOCKED;
161
162	rpc->rpd = dev;
163	INIT_WORK(&rpc->dpc_handler, aer_isr, (void *)dev);
164	rpc->prod_idx = rpc->cons_idx = 0;
165	mutex_init(&rpc->rpc_mutex);
166	init_waitqueue_head(&rpc->wait_release);
167
168	/* Use PCIE bus function to store rpc into PCIE device */
169	set_service_data(dev, rpc);
170
171	return rpc;
172	}
173
174	/**
175	* aer_remove - clean up resources
176	* @dev: pointer to the pcie_dev data structure
177	*
178	* Invoked when PCI Express bus unloads or AER probe fails.
179	**/
180	static void aer_remove(struct pcie_device *dev)
181	{
182	struct aer_rpc *rpc = get_service_data(dev);
183
184	if (rpc) {
185	/* If register interrupt service, it must be free. */
186	if (rpc->isr)
187	free_irq(dev->irq, dev);
188
189	wait_event(rpc->wait_release, rpc->prod_idx == rpc->cons_idx);
190
191	aer_delete_rootport(rpc);
192	set_service_data(dev, NULL);
193	}
194	}
195
196	/**
197	* aer_probe - initialize resources
198	* @dev: pointer to the pcie_dev data structure
199	* @id: pointer to the service id data structure
200	*
201	* Invoked when PCI Express bus loads AER service driver.
202	**/
203	static int __devinit aer_probe (struct pcie_device *dev,
204	const struct pcie_port_service_id *id )
205	{
206	int status;
207	struct aer_rpc *rpc;
208	struct device *device = &dev->device;
209
210	/* Init */
211	if ((status = aer_init(dev)))
212	return status;
213
214	/* Alloc rpc data structure */
215	if (!(rpc = aer_alloc_rpc(dev))) {
216	printk(KERN_DEBUG "%s: Alloc rpc fails on PCIE device[%s]\n",
217	__FUNCTION__, device->bus_id);
218	aer_remove(dev);
219	return -ENOMEM;
220	}
221
222	/* Request IRQ ISR */
223	if ((status = request_irq(dev->irq, aer_irq, SA_SHIRQ, "aerdrv",
224	dev))) {
225	printk(KERN_DEBUG "%s: Request ISR fails on PCIE device[%s]\n",
226	__FUNCTION__, device->bus_id);
227	aer_remove(dev);
228	return status;
229	}
230
231	rpc->isr = 1;
232
233	aer_enable_rootport(rpc);
234
235	return status;
236	}
237
238	/**
239	* aer_root_reset - reset link on Root Port
240	* @dev: pointer to Root Port's pci_dev data structure
241	*
242	* Invoked by Port Bus driver when performing link reset at Root Port.
243	**/
244	static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
245	{
246	u16 p2p_ctrl;
247	u32 status;
248	int pos;
249
250	pos = pci_find_aer_capability(dev);
251
252	/* Disable Root's interrupt in response to error messages */
253	pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, 0);
254
255	/* Assert Secondary Bus Reset */
256	pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &p2p_ctrl);
257	p2p_ctrl \|= PCI_CB_BRIDGE_CTL_CB_RESET;
258	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);
259
260	/* De-assert Secondary Bus Reset */
261	p2p_ctrl &= ~PCI_CB_BRIDGE_CTL_CB_RESET;
262	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);
263
264	/*
265	* System software must wait for at least 100ms from the end
266	* of a reset of one or more device before it is permitted
267	* to issue Configuration Requests to those devices.
268	*/
269	msleep(200);
270	printk(KERN_DEBUG "Complete link reset at Root[%s]\n", dev->dev.bus_id);
271
272	/* Enable Root Port's interrupt in response to error messages */
273	pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, &status);
274	pci_write_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, status);
275	pci_write_config_dword(dev,
276	pos + PCI_ERR_ROOT_COMMAND,
277	ROOT_PORT_INTR_ON_MESG_MASK);
278
279	return PCI_ERS_RESULT_RECOVERED;
280	}
281
282	/**
283	* aer_error_detected - update severity status
284	* @dev: pointer to Root Port's pci_dev data structure
285	* @error: error severity being notified by port bus
286	*
287	* Invoked by Port Bus driver during error recovery.
288	**/
289	static pci_ers_result_t aer_error_detected(struct pci_dev *dev,
290	enum pci_channel_state error)
291	{
292	/* Root Port has no impact. Always recovers. */
293	return PCI_ERS_RESULT_CAN_RECOVER;
294	}
295
296	/**
297	* aer_error_resume - clean up corresponding error status bits
298	* @dev: pointer to Root Port's pci_dev data structure
299	*
300	* Invoked by Port Bus driver during nonfatal recovery.
301	**/
302	static void aer_error_resume(struct pci_dev *dev)
303	{
304	int pos;
305	u32 status, mask;
306	u16 reg16;
307
308	/* Clean up Root device status */
309	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
310	pci_read_config_word(dev, pos + PCI_EXP_DEVSTA, &reg16);
311	pci_write_config_word(dev, pos + PCI_EXP_DEVSTA, reg16);
312
313	/* Clean AER Root Error Status */
314	pos = pci_find_aer_capability(dev);
315	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, &status);
316	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &mask);
317	if (dev->error_state == pci_channel_io_normal)
318	status &= ~mask; /* Clear corresponding nonfatal bits */
319	else
320	status &= mask; /* Clear corresponding fatal bits */
321	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, status);
322	}
323
324	/**
325	* aer_service_init - register AER root service driver
326	*
327	* Invoked when AER root service driver is loaded.
328	**/
329	static int __init aer_service_init(void)
330	{
331	return pcie_port_service_register(&aerdrv);
332	}
333
334	/**
335	* aer_service_exit - unregister AER root service driver
336	*
337	* Invoked when AER root service driver is unloaded.
338	**/
339	static void __exit aer_service_exit(void)
340	{
341	pcie_port_service_unregister(&aerdrv);
342	}
343
344	module_init(aer_service_init);
345	module_exit(aer_service_exit);