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>
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");
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)
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);
52 * PCI Express bus's AER Root service driver data structure
54 static struct pcie_port_service_id aer_id[] = {
58 .port_type = PCIE_RC_PORT,
59 .service_type = PCIE_PORT_SERVICE_AER,
61 { /* end: all zeroes */ }
64 static struct pci_error_handlers aer_error_handlers = {
65 .error_detected = aer_error_detected,
66 .resume = aer_error_resume,
69 static struct pcie_port_service_driver aerdrv = {
71 .id_table = &aer_id[0],
76 .suspend = aer_suspend,
79 .err_handler = &aer_error_handlers,
81 .reset_link = aer_root_reset,
85 * aer_irq - Root Port's ISR
86 * @irq: IRQ assigned to Root Port
87 * @context: pointer to Root Port data structure
88 * @r: pointer struct pt_regs
90 * Invoked when Root Port detects AER messages.
92 static irqreturn_t aer_irq(int irq, void *context, struct pt_regs * r)
94 unsigned int status, id;
95 struct pcie_device *pdev = (struct pcie_device *)context;
96 struct aer_rpc *rpc = get_service_data(pdev);
101 pos = pci_find_aer_capability(pdev->port);
103 * Must lock access to Root Error Status Reg, Root Error ID Reg,
104 * and Root error producer/consumer index
106 spin_lock_irqsave(&rpc->e_lock, flags);
108 /* Read error status */
109 pci_read_config_dword(pdev->port, pos + PCI_ERR_ROOT_STATUS, &status);
110 if (!(status & ROOT_ERR_STATUS_MASKS)) {
111 spin_unlock_irqrestore(&rpc->e_lock, flags);
115 /* Read error source and clear error status */
116 pci_read_config_dword(pdev->port, pos + PCI_ERR_ROOT_COR_SRC, &id);
117 pci_write_config_dword(pdev->port, pos + PCI_ERR_ROOT_STATUS, status);
119 /* Store error source for later DPC handler */
120 next_prod_idx = rpc->prod_idx + 1;
121 if (next_prod_idx == AER_ERROR_SOURCES_MAX)
123 if (next_prod_idx == rpc->cons_idx) {
125 * Error Storm Condition - possibly the same error occurred.
128 spin_unlock_irqrestore(&rpc->e_lock, flags);
131 rpc->e_sources[rpc->prod_idx].status = status;
132 rpc->e_sources[rpc->prod_idx].id = id;
133 rpc->prod_idx = next_prod_idx;
134 spin_unlock_irqrestore(&rpc->e_lock, flags);
136 /* Invoke DPC handler */
137 schedule_work(&rpc->dpc_handler);
143 * aer_alloc_rpc - allocate Root Port data structure
144 * @dev: pointer to the pcie_dev data structure
146 * Invoked when Root Port's AER service is loaded.
148 static struct aer_rpc* aer_alloc_rpc(struct pcie_device *dev)
152 if (!(rpc = (struct aer_rpc *)kmalloc(sizeof(struct aer_rpc),
156 memset(rpc, 0, sizeof(struct aer_rpc));
158 * Initialize Root lock access, e_lock, to Root Error Status Reg,
159 * Root Error ID Reg, and Root error producer/consumer index.
161 rpc->e_lock = SPIN_LOCK_UNLOCKED;
164 INIT_WORK(&rpc->dpc_handler, aer_isr, (void *)dev);
165 rpc->prod_idx = rpc->cons_idx = 0;
166 mutex_init(&rpc->rpc_mutex);
167 init_waitqueue_head(&rpc->wait_release);
169 /* Use PCIE bus function to store rpc into PCIE device */
170 set_service_data(dev, rpc);
176 * aer_remove - clean up resources
177 * @dev: pointer to the pcie_dev data structure
179 * Invoked when PCI Express bus unloads or AER probe fails.
181 static void aer_remove(struct pcie_device *dev)
183 struct aer_rpc *rpc = get_service_data(dev);
186 /* If register interrupt service, it must be free. */
188 free_irq(dev->irq, dev);
190 wait_event(rpc->wait_release, rpc->prod_idx == rpc->cons_idx);
192 aer_delete_rootport(rpc);
193 set_service_data(dev, NULL);
198 * aer_probe - initialize resources
199 * @dev: pointer to the pcie_dev data structure
200 * @id: pointer to the service id data structure
202 * Invoked when PCI Express bus loads AER service driver.
204 static int __devinit aer_probe (struct pcie_device *dev,
205 const struct pcie_port_service_id *id )
209 struct device *device = &dev->device;
212 if ((status = aer_init(dev)))
215 /* Alloc rpc data structure */
216 if (!(rpc = aer_alloc_rpc(dev))) {
217 printk(KERN_DEBUG "%s: Alloc rpc fails on PCIE device[%s]\n",
218 __FUNCTION__, device->bus_id);
223 /* Request IRQ ISR */
224 if ((status = request_irq(dev->irq, aer_irq, SA_SHIRQ, "aerdrv",
226 printk(KERN_DEBUG "%s: Request ISR fails on PCIE device[%s]\n",
227 __FUNCTION__, device->bus_id);
234 aer_enable_rootport(rpc);
240 * aer_root_reset - reset link on Root Port
241 * @dev: pointer to Root Port's pci_dev data structure
243 * Invoked by Port Bus driver when performing link reset at Root Port.
245 static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
251 pos = pci_find_aer_capability(dev);
253 /* Disable Root's interrupt in response to error messages */
254 pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, 0);
256 /* Assert Secondary Bus Reset */
257 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &p2p_ctrl);
258 p2p_ctrl |= PCI_CB_BRIDGE_CTL_CB_RESET;
259 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);
261 /* De-assert Secondary Bus Reset */
262 p2p_ctrl &= ~PCI_CB_BRIDGE_CTL_CB_RESET;
263 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);
266 * System software must wait for at least 100ms from the end
267 * of a reset of one or more device before it is permitted
268 * to issue Configuration Requests to those devices.
271 printk(KERN_DEBUG "Complete link reset at Root[%s]\n", dev->dev.bus_id);
273 /* Enable Root Port's interrupt in response to error messages */
274 pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, &status);
275 pci_write_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, status);
276 pci_write_config_dword(dev,
277 pos + PCI_ERR_ROOT_COMMAND,
278 ROOT_PORT_INTR_ON_MESG_MASK);
280 return PCI_ERS_RESULT_RECOVERED;
284 * aer_error_detected - update severity status
285 * @dev: pointer to Root Port's pci_dev data structure
286 * @error: error severity being notified by port bus
288 * Invoked by Port Bus driver during error recovery.
290 static pci_ers_result_t aer_error_detected(struct pci_dev *dev,
291 enum pci_channel_state error)
293 /* Root Port has no impact. Always recovers. */
294 return PCI_ERS_RESULT_CAN_RECOVER;
298 * aer_error_resume - clean up corresponding error status bits
299 * @dev: pointer to Root Port's pci_dev data structure
301 * Invoked by Port Bus driver during nonfatal recovery.
303 static void aer_error_resume(struct pci_dev *dev)
309 /* Clean up Root device status */
310 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
311 pci_read_config_word(dev, pos + PCI_EXP_DEVSTA, ®16);
312 pci_write_config_word(dev, pos + PCI_EXP_DEVSTA, reg16);
314 /* Clean AER Root Error Status */
315 pos = pci_find_aer_capability(dev);
316 pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, &status);
317 pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &mask);
318 if (dev->error_state == pci_channel_io_normal)
319 status &= ~mask; /* Clear corresponding nonfatal bits */
321 status &= mask; /* Clear corresponding fatal bits */
322 pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, status);
326 * aer_service_init - register AER root service driver
328 * Invoked when AER root service driver is loaded.
330 static int __init aer_service_init(void)
332 return pcie_port_service_register(&aerdrv);
336 * aer_service_exit - unregister AER root service driver
338 * Invoked when AER root service driver is unloaded.
340 static void __exit aer_service_exit(void)
342 pcie_port_service_unregister(&aerdrv);
345 module_init(aer_service_init);
346 module_exit(aer_service_exit);