2 * drivers/pci/pcie/aer/aerdrv.c
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
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.
12 * Copyright (C) 2006 Intel Corp.
13 * Tom Long Nguyen (tom.l.nguyen@intel.com)
14 * Zhang Yanmin (yanmin.zhang@intel.com)
18 #include <linux/module.h>
19 #include <linux/pci.h>
20 #include <linux/kernel.h>
21 #include <linux/errno.h>
23 #include <linux/init.h>
24 #include <linux/interrupt.h>
25 #include <linux/delay.h>
26 #include <linux/pcieport_if.h>
29 #include "../../pci.h"
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");
41 static int __devinit aer_probe (struct pcie_device *dev);
42 static void aer_remove(struct pcie_device *dev);
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);
48 static struct pci_error_handlers aer_error_handlers = {
49 .error_detected = aer_error_detected,
50 .resume = aer_error_resume,
53 static struct pcie_port_service_driver aerdriver = {
55 .port_type = PCIE_ANY_PORT,
56 .service = PCIE_PORT_SERVICE_AER,
61 .err_handler = &aer_error_handlers,
63 .reset_link = aer_root_reset,
66 static int pcie_aer_disable;
70 pcie_aer_disable = 1; /* has priority over 'forceload' */
74 * aer_irq - Root Port's ISR
75 * @irq: IRQ assigned to Root Port
76 * @context: pointer to Root Port data structure
78 * Invoked when Root Port detects AER messages.
80 static irqreturn_t aer_irq(int irq, void *context)
82 unsigned int status, id;
83 struct pcie_device *pdev = (struct pcie_device *)context;
84 struct aer_rpc *rpc = get_service_data(pdev);
89 pos = pci_find_ext_capability(pdev->port, PCI_EXT_CAP_ID_ERR);
91 * Must lock access to Root Error Status Reg, Root Error ID Reg,
92 * and Root error producer/consumer index
94 spin_lock_irqsave(&rpc->e_lock, flags);
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);
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);
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)
111 if (next_prod_idx == rpc->cons_idx) {
113 * Error Storm Condition - possibly the same error occurred.
116 spin_unlock_irqrestore(&rpc->e_lock, flags);
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);
124 /* Invoke DPC handler */
125 schedule_work(&rpc->dpc_handler);
131 * aer_alloc_rpc - allocate Root Port data structure
132 * @dev: pointer to the pcie_dev data structure
134 * Invoked when Root Port's AER service is loaded.
136 static struct aer_rpc* aer_alloc_rpc(struct pcie_device *dev)
140 if (!(rpc = kzalloc(sizeof(struct aer_rpc),
145 * Initialize Root lock access, e_lock, to Root Error Status Reg,
146 * Root Error ID Reg, and Root error producer/consumer index.
148 spin_lock_init(&rpc->e_lock);
151 INIT_WORK(&rpc->dpc_handler, aer_isr);
152 rpc->prod_idx = rpc->cons_idx = 0;
153 mutex_init(&rpc->rpc_mutex);
154 init_waitqueue_head(&rpc->wait_release);
156 /* Use PCIE bus function to store rpc into PCIE device */
157 set_service_data(dev, rpc);
163 * aer_remove - clean up resources
164 * @dev: pointer to the pcie_dev data structure
166 * Invoked when PCI Express bus unloads or AER probe fails.
168 static void aer_remove(struct pcie_device *dev)
170 struct aer_rpc *rpc = get_service_data(dev);
173 /* If register interrupt service, it must be free. */
175 free_irq(dev->irq, dev);
177 wait_event(rpc->wait_release, rpc->prod_idx == rpc->cons_idx);
179 aer_delete_rootport(rpc);
180 set_service_data(dev, NULL);
185 * aer_probe - initialize resources
186 * @dev: pointer to the pcie_dev data structure
187 * @id: pointer to the service id data structure
189 * Invoked when PCI Express bus loads AER service driver.
191 static int __devinit aer_probe (struct pcie_device *dev)
195 struct device *device = &dev->device;
198 if ((status = aer_init(dev)))
201 /* Alloc rpc data structure */
202 if (!(rpc = aer_alloc_rpc(dev))) {
203 dev_printk(KERN_DEBUG, device, "alloc rpc failed\n");
208 /* Request IRQ ISR */
209 if ((status = request_irq(dev->irq, aer_irq, IRQF_SHARED, "aerdrv",
211 dev_printk(KERN_DEBUG, device, "request IRQ failed\n");
218 aer_enable_rootport(rpc);
224 * aer_root_reset - reset link on Root Port
225 * @dev: pointer to Root Port's pci_dev data structure
227 * Invoked by Port Bus driver when performing link reset at Root Port.
229 static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
235 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
237 /* Disable Root's interrupt in response to error messages */
238 pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, 0);
240 /* Assert Secondary Bus Reset */
241 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &p2p_ctrl);
242 p2p_ctrl |= PCI_CB_BRIDGE_CTL_CB_RESET;
243 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);
245 /* De-assert Secondary Bus Reset */
246 p2p_ctrl &= ~PCI_CB_BRIDGE_CTL_CB_RESET;
247 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);
250 * System software must wait for at least 100ms from the end
251 * of a reset of one or more device before it is permitted
252 * to issue Configuration Requests to those devices.
255 dev_printk(KERN_DEBUG, &dev->dev, "Root Port link has been reset\n");
257 /* Enable Root Port's interrupt in response to error messages */
258 pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, &status);
259 pci_write_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, status);
260 pci_write_config_dword(dev,
261 pos + PCI_ERR_ROOT_COMMAND,
262 ROOT_PORT_INTR_ON_MESG_MASK);
264 return PCI_ERS_RESULT_RECOVERED;
268 * aer_error_detected - update severity status
269 * @dev: pointer to Root Port's pci_dev data structure
270 * @error: error severity being notified by port bus
272 * Invoked by Port Bus driver during error recovery.
274 static pci_ers_result_t aer_error_detected(struct pci_dev *dev,
275 enum pci_channel_state error)
277 /* Root Port has no impact. Always recovers. */
278 return PCI_ERS_RESULT_CAN_RECOVER;
282 * aer_error_resume - clean up corresponding error status bits
283 * @dev: pointer to Root Port's pci_dev data structure
285 * Invoked by Port Bus driver during nonfatal recovery.
287 static void aer_error_resume(struct pci_dev *dev)
293 /* Clean up Root device status */
294 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
295 pci_read_config_word(dev, pos + PCI_EXP_DEVSTA, ®16);
296 pci_write_config_word(dev, pos + PCI_EXP_DEVSTA, reg16);
298 /* Clean AER Root Error Status */
299 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
300 pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, &status);
301 pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &mask);
302 if (dev->error_state == pci_channel_io_normal)
303 status &= ~mask; /* Clear corresponding nonfatal bits */
305 status &= mask; /* Clear corresponding fatal bits */
306 pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, status);
310 * aer_service_init - register AER root service driver
312 * Invoked when AER root service driver is loaded.
314 static int __init aer_service_init(void)
316 if (pcie_aer_disable)
318 return pcie_port_service_register(&aerdriver);
322 * aer_service_exit - unregister AER root service driver
324 * Invoked when AER root service driver is unloaded.
326 static void __exit aer_service_exit(void)
328 pcie_port_service_unregister(&aerdriver);
331 module_init(aer_service_init);
332 module_exit(aer_service_exit);