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/sched.h>
21 #include <linux/kernel.h>
22 #include <linux/errno.h>
24 #include <linux/init.h>
25 #include <linux/interrupt.h>
26 #include <linux/delay.h>
27 #include <linux/pcieport_if.h>
28 #include <linux/slab.h>
31 #include "../../pci.h"
36 #define DRIVER_VERSION "v1.0"
37 #define DRIVER_AUTHOR "tom.l.nguyen@intel.com"
38 #define DRIVER_DESC "Root Port Advanced Error Reporting Driver"
39 MODULE_AUTHOR(DRIVER_AUTHOR);
40 MODULE_DESCRIPTION(DRIVER_DESC);
41 MODULE_LICENSE("GPL");
43 static int __devinit aer_probe(struct pcie_device *dev);
44 static void aer_remove(struct pcie_device *dev);
45 static pci_ers_result_t aer_error_detected(struct pci_dev *dev,
46 enum pci_channel_state error);
47 static void aer_error_resume(struct pci_dev *dev);
48 static pci_ers_result_t aer_root_reset(struct pci_dev *dev);
50 static struct pci_error_handlers aer_error_handlers = {
51 .error_detected = aer_error_detected,
52 .resume = aer_error_resume,
55 static struct pcie_port_service_driver aerdriver = {
57 .port_type = PCI_EXP_TYPE_ROOT_PORT,
58 .service = PCIE_PORT_SERVICE_AER,
63 .err_handler = &aer_error_handlers,
65 .reset_link = aer_root_reset,
68 static int pcie_aer_disable;
72 pcie_aer_disable = 1; /* has priority over 'forceload' */
75 static int set_device_error_reporting(struct pci_dev *dev, void *data)
77 bool enable = *((bool *)data);
79 if ((dev->pcie_type == PCI_EXP_TYPE_ROOT_PORT) ||
80 (dev->pcie_type == PCI_EXP_TYPE_UPSTREAM) ||
81 (dev->pcie_type == PCI_EXP_TYPE_DOWNSTREAM)) {
83 pci_enable_pcie_error_reporting(dev);
85 pci_disable_pcie_error_reporting(dev);
89 pcie_set_ecrc_checking(dev);
95 * set_downstream_devices_error_reporting - enable/disable the error reporting bits on the root port and its downstream ports.
96 * @dev: pointer to root port's pci_dev data structure
97 * @enable: true = enable error reporting, false = disable error reporting.
99 static void set_downstream_devices_error_reporting(struct pci_dev *dev,
102 set_device_error_reporting(dev, &enable);
104 if (!dev->subordinate)
106 pci_walk_bus(dev->subordinate, set_device_error_reporting, &enable);
110 * aer_enable_rootport - enable Root Port's interrupts when receiving messages
111 * @rpc: pointer to a Root Port data structure
113 * Invoked when PCIe bus loads AER service driver.
115 static void aer_enable_rootport(struct aer_rpc *rpc)
117 struct pci_dev *pdev = rpc->rpd->port;
122 pos = pci_pcie_cap(pdev);
123 /* Clear PCIe Capability's Device Status */
124 pci_read_config_word(pdev, pos+PCI_EXP_DEVSTA, ®16);
125 pci_write_config_word(pdev, pos+PCI_EXP_DEVSTA, reg16);
127 /* Disable system error generation in response to error messages */
128 pci_read_config_word(pdev, pos + PCI_EXP_RTCTL, ®16);
129 reg16 &= ~(SYSTEM_ERROR_INTR_ON_MESG_MASK);
130 pci_write_config_word(pdev, pos + PCI_EXP_RTCTL, reg16);
132 aer_pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ERR);
133 /* Clear error status */
134 pci_read_config_dword(pdev, aer_pos + PCI_ERR_ROOT_STATUS, ®32);
135 pci_write_config_dword(pdev, aer_pos + PCI_ERR_ROOT_STATUS, reg32);
136 pci_read_config_dword(pdev, aer_pos + PCI_ERR_COR_STATUS, ®32);
137 pci_write_config_dword(pdev, aer_pos + PCI_ERR_COR_STATUS, reg32);
138 pci_read_config_dword(pdev, aer_pos + PCI_ERR_UNCOR_STATUS, ®32);
139 pci_write_config_dword(pdev, aer_pos + PCI_ERR_UNCOR_STATUS, reg32);
142 * Enable error reporting for the root port device and downstream port
145 set_downstream_devices_error_reporting(pdev, true);
147 /* Enable Root Port's interrupt in response to error messages */
148 pci_read_config_dword(pdev, aer_pos + PCI_ERR_ROOT_COMMAND, ®32);
149 reg32 |= ROOT_PORT_INTR_ON_MESG_MASK;
150 pci_write_config_dword(pdev, aer_pos + PCI_ERR_ROOT_COMMAND, reg32);
154 * aer_disable_rootport - disable Root Port's interrupts when receiving messages
155 * @rpc: pointer to a Root Port data structure
157 * Invoked when PCIe bus unloads AER service driver.
159 static void aer_disable_rootport(struct aer_rpc *rpc)
161 struct pci_dev *pdev = rpc->rpd->port;
166 * Disable error reporting for the root port device and downstream port
169 set_downstream_devices_error_reporting(pdev, false);
171 pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ERR);
172 /* Disable Root's interrupt in response to error messages */
173 pci_read_config_dword(pdev, pos + PCI_ERR_ROOT_COMMAND, ®32);
174 reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
175 pci_write_config_dword(pdev, pos + PCI_ERR_ROOT_COMMAND, reg32);
177 /* Clear Root's error status reg */
178 pci_read_config_dword(pdev, pos + PCI_ERR_ROOT_STATUS, ®32);
179 pci_write_config_dword(pdev, pos + PCI_ERR_ROOT_STATUS, reg32);
183 * aer_irq - Root Port's ISR
184 * @irq: IRQ assigned to Root Port
185 * @context: pointer to Root Port data structure
187 * Invoked when Root Port detects AER messages.
189 irqreturn_t aer_irq(int irq, void *context)
191 unsigned int status, id;
192 struct pcie_device *pdev = (struct pcie_device *)context;
193 struct aer_rpc *rpc = get_service_data(pdev);
198 pos = pci_find_ext_capability(pdev->port, PCI_EXT_CAP_ID_ERR);
200 * Must lock access to Root Error Status Reg, Root Error ID Reg,
201 * and Root error producer/consumer index
203 spin_lock_irqsave(&rpc->e_lock, flags);
205 /* Read error status */
206 pci_read_config_dword(pdev->port, pos + PCI_ERR_ROOT_STATUS, &status);
207 if (!(status & (PCI_ERR_ROOT_UNCOR_RCV|PCI_ERR_ROOT_COR_RCV))) {
208 spin_unlock_irqrestore(&rpc->e_lock, flags);
212 /* Read error source and clear error status */
213 pci_read_config_dword(pdev->port, pos + PCI_ERR_ROOT_ERR_SRC, &id);
214 pci_write_config_dword(pdev->port, pos + PCI_ERR_ROOT_STATUS, status);
216 /* Store error source for later DPC handler */
217 next_prod_idx = rpc->prod_idx + 1;
218 if (next_prod_idx == AER_ERROR_SOURCES_MAX)
220 if (next_prod_idx == rpc->cons_idx) {
222 * Error Storm Condition - possibly the same error occurred.
225 spin_unlock_irqrestore(&rpc->e_lock, flags);
228 rpc->e_sources[rpc->prod_idx].status = status;
229 rpc->e_sources[rpc->prod_idx].id = id;
230 rpc->prod_idx = next_prod_idx;
231 spin_unlock_irqrestore(&rpc->e_lock, flags);
233 /* Invoke DPC handler */
234 schedule_work(&rpc->dpc_handler);
238 EXPORT_SYMBOL_GPL(aer_irq);
241 * aer_alloc_rpc - allocate Root Port data structure
242 * @dev: pointer to the pcie_dev data structure
244 * Invoked when Root Port's AER service is loaded.
246 static struct aer_rpc *aer_alloc_rpc(struct pcie_device *dev)
250 rpc = kzalloc(sizeof(struct aer_rpc), GFP_KERNEL);
255 * Initialize Root lock access, e_lock, to Root Error Status Reg,
256 * Root Error ID Reg, and Root error producer/consumer index.
258 spin_lock_init(&rpc->e_lock);
261 INIT_WORK(&rpc->dpc_handler, aer_isr);
262 rpc->prod_idx = rpc->cons_idx = 0;
263 mutex_init(&rpc->rpc_mutex);
264 init_waitqueue_head(&rpc->wait_release);
266 /* Use PCIe bus function to store rpc into PCIe device */
267 set_service_data(dev, rpc);
273 * aer_remove - clean up resources
274 * @dev: pointer to the pcie_dev data structure
276 * Invoked when PCI Express bus unloads or AER probe fails.
278 static void aer_remove(struct pcie_device *dev)
280 struct aer_rpc *rpc = get_service_data(dev);
283 /* If register interrupt service, it must be free. */
285 free_irq(dev->irq, dev);
287 wait_event(rpc->wait_release, rpc->prod_idx == rpc->cons_idx);
289 aer_disable_rootport(rpc);
291 set_service_data(dev, NULL);
296 * aer_probe - initialize resources
297 * @dev: pointer to the pcie_dev data structure
298 * @id: pointer to the service id data structure
300 * Invoked when PCI Express bus loads AER service driver.
302 static int __devinit aer_probe(struct pcie_device *dev)
306 struct device *device = &dev->device;
309 status = aer_init(dev);
313 /* Alloc rpc data structure */
314 rpc = aer_alloc_rpc(dev);
316 dev_printk(KERN_DEBUG, device, "alloc rpc failed\n");
321 /* Request IRQ ISR */
322 status = request_irq(dev->irq, aer_irq, IRQF_SHARED, "aerdrv", dev);
324 dev_printk(KERN_DEBUG, device, "request IRQ failed\n");
331 aer_enable_rootport(rpc);
337 * aer_root_reset - reset link on Root Port
338 * @dev: pointer to Root Port's pci_dev data structure
340 * Invoked by Port Bus driver when performing link reset at Root Port.
342 static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
347 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
349 /* Disable Root's interrupt in response to error messages */
350 pci_read_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, ®32);
351 reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
352 pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, reg32);
354 aer_do_secondary_bus_reset(dev);
355 dev_printk(KERN_DEBUG, &dev->dev, "Root Port link has been reset\n");
357 /* Clear Root Error Status */
358 pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, ®32);
359 pci_write_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, reg32);
361 /* Enable Root Port's interrupt in response to error messages */
362 pci_read_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, ®32);
363 reg32 |= ROOT_PORT_INTR_ON_MESG_MASK;
364 pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, reg32);
366 return PCI_ERS_RESULT_RECOVERED;
370 * aer_error_detected - update severity status
371 * @dev: pointer to Root Port's pci_dev data structure
372 * @error: error severity being notified by port bus
374 * Invoked by Port Bus driver during error recovery.
376 static pci_ers_result_t aer_error_detected(struct pci_dev *dev,
377 enum pci_channel_state error)
379 /* Root Port has no impact. Always recovers. */
380 return PCI_ERS_RESULT_CAN_RECOVER;
384 * aer_error_resume - clean up corresponding error status bits
385 * @dev: pointer to Root Port's pci_dev data structure
387 * Invoked by Port Bus driver during nonfatal recovery.
389 static void aer_error_resume(struct pci_dev *dev)
395 /* Clean up Root device status */
396 pos = pci_pcie_cap(dev);
397 pci_read_config_word(dev, pos + PCI_EXP_DEVSTA, ®16);
398 pci_write_config_word(dev, pos + PCI_EXP_DEVSTA, reg16);
400 /* Clean AER Root Error Status */
401 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
402 pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, &status);
403 pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &mask);
404 if (dev->error_state == pci_channel_io_normal)
405 status &= ~mask; /* Clear corresponding nonfatal bits */
407 status &= mask; /* Clear corresponding fatal bits */
408 pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, status);
412 * aer_service_init - register AER root service driver
414 * Invoked when AER root service driver is loaded.
416 static int __init aer_service_init(void)
418 if (pcie_aer_disable)
420 if (!pci_msi_enabled())
422 return pcie_port_service_register(&aerdriver);
426 * aer_service_exit - unregister AER root service driver
428 * Invoked when AER root service driver is unloaded.
430 static void __exit aer_service_exit(void)
432 pcie_port_service_unregister(&aerdriver);
435 module_init(aer_service_init);
436 module_exit(aer_service_exit);