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/pci.h>
19 #include <linux/pci-acpi.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"
40 static int aer_probe(struct pcie_device
*dev
);
41 static void aer_remove(struct pcie_device
*dev
);
42 static pci_ers_result_t
aer_error_detected(struct pci_dev
*dev
,
43 enum pci_channel_state error
);
44 static void aer_error_resume(struct pci_dev
*dev
);
45 static pci_ers_result_t
aer_root_reset(struct pci_dev
*dev
);
47 static const struct pci_error_handlers aer_error_handlers
= {
48 .error_detected
= aer_error_detected
,
49 .resume
= aer_error_resume
,
52 static struct pcie_port_service_driver aerdriver
= {
54 .port_type
= PCI_EXP_TYPE_ROOT_PORT
,
55 .service
= PCIE_PORT_SERVICE_AER
,
60 .err_handler
= &aer_error_handlers
,
62 .reset_link
= aer_root_reset
,
65 static int pcie_aer_disable
;
69 pcie_aer_disable
= 1; /* has priority over 'forceload' */
72 bool pci_aer_available(void)
74 return !pcie_aer_disable
&& pci_msi_enabled();
77 static int set_device_error_reporting(struct pci_dev
*dev
, void *data
)
79 bool enable
= *((bool *)data
);
80 int type
= pci_pcie_type(dev
);
82 if ((type
== PCI_EXP_TYPE_ROOT_PORT
) ||
83 (type
== PCI_EXP_TYPE_UPSTREAM
) ||
84 (type
== PCI_EXP_TYPE_DOWNSTREAM
)) {
86 pci_enable_pcie_error_reporting(dev
);
88 pci_disable_pcie_error_reporting(dev
);
92 pcie_set_ecrc_checking(dev
);
98 * set_downstream_devices_error_reporting - enable/disable the error reporting bits on the root port and its downstream ports.
99 * @dev: pointer to root port's pci_dev data structure
100 * @enable: true = enable error reporting, false = disable error reporting.
102 static void set_downstream_devices_error_reporting(struct pci_dev
*dev
,
105 set_device_error_reporting(dev
, &enable
);
107 if (!dev
->subordinate
)
109 pci_walk_bus(dev
->subordinate
, set_device_error_reporting
, &enable
);
113 * aer_enable_rootport - enable Root Port's interrupts when receiving messages
114 * @rpc: pointer to a Root Port data structure
116 * Invoked when PCIe bus loads AER service driver.
118 static void aer_enable_rootport(struct aer_rpc
*rpc
)
120 struct pci_dev
*pdev
= rpc
->rpd
->port
;
125 /* Clear PCIe Capability's Device Status */
126 pcie_capability_read_word(pdev
, PCI_EXP_DEVSTA
, ®16
);
127 pcie_capability_write_word(pdev
, PCI_EXP_DEVSTA
, reg16
);
129 /* Disable system error generation in response to error messages */
130 pcie_capability_clear_word(pdev
, PCI_EXP_RTCTL
,
131 SYSTEM_ERROR_INTR_ON_MESG_MASK
);
133 aer_pos
= pci_find_ext_capability(pdev
, PCI_EXT_CAP_ID_ERR
);
134 /* Clear error status */
135 pci_read_config_dword(pdev
, aer_pos
+ PCI_ERR_ROOT_STATUS
, ®32
);
136 pci_write_config_dword(pdev
, aer_pos
+ PCI_ERR_ROOT_STATUS
, reg32
);
137 pci_read_config_dword(pdev
, aer_pos
+ PCI_ERR_COR_STATUS
, ®32
);
138 pci_write_config_dword(pdev
, aer_pos
+ PCI_ERR_COR_STATUS
, reg32
);
139 pci_read_config_dword(pdev
, aer_pos
+ PCI_ERR_UNCOR_STATUS
, ®32
);
140 pci_write_config_dword(pdev
, aer_pos
+ PCI_ERR_UNCOR_STATUS
, reg32
);
143 * Enable error reporting for the root port device and downstream port
146 set_downstream_devices_error_reporting(pdev
, true);
148 /* Enable Root Port's interrupt in response to error messages */
149 pci_read_config_dword(pdev
, aer_pos
+ PCI_ERR_ROOT_COMMAND
, ®32
);
150 reg32
|= ROOT_PORT_INTR_ON_MESG_MASK
;
151 pci_write_config_dword(pdev
, aer_pos
+ PCI_ERR_ROOT_COMMAND
, reg32
);
155 * aer_disable_rootport - disable Root Port's interrupts when receiving messages
156 * @rpc: pointer to a Root Port data structure
158 * Invoked when PCIe bus unloads AER service driver.
160 static void aer_disable_rootport(struct aer_rpc
*rpc
)
162 struct pci_dev
*pdev
= rpc
->rpd
->port
;
167 * Disable error reporting for the root port device and downstream port
170 set_downstream_devices_error_reporting(pdev
, false);
172 pos
= pci_find_ext_capability(pdev
, PCI_EXT_CAP_ID_ERR
);
173 /* Disable Root's interrupt in response to error messages */
174 pci_read_config_dword(pdev
, pos
+ PCI_ERR_ROOT_COMMAND
, ®32
);
175 reg32
&= ~ROOT_PORT_INTR_ON_MESG_MASK
;
176 pci_write_config_dword(pdev
, pos
+ PCI_ERR_ROOT_COMMAND
, reg32
);
178 /* Clear Root's error status reg */
179 pci_read_config_dword(pdev
, pos
+ PCI_ERR_ROOT_STATUS
, ®32
);
180 pci_write_config_dword(pdev
, pos
+ PCI_ERR_ROOT_STATUS
, reg32
);
184 * aer_irq - Root Port's ISR
185 * @irq: IRQ assigned to Root Port
186 * @context: pointer to Root Port data structure
188 * Invoked when Root Port detects AER messages.
190 irqreturn_t
aer_irq(int irq
, void *context
)
192 unsigned int status
, id
;
193 struct pcie_device
*pdev
= (struct pcie_device
*)context
;
194 struct aer_rpc
*rpc
= get_service_data(pdev
);
199 pos
= pci_find_ext_capability(pdev
->port
, PCI_EXT_CAP_ID_ERR
);
201 * Must lock access to Root Error Status Reg, Root Error ID Reg,
202 * and Root error producer/consumer index
204 spin_lock_irqsave(&rpc
->e_lock
, flags
);
206 /* Read error status */
207 pci_read_config_dword(pdev
->port
, pos
+ PCI_ERR_ROOT_STATUS
, &status
);
208 if (!(status
& (PCI_ERR_ROOT_UNCOR_RCV
|PCI_ERR_ROOT_COR_RCV
))) {
209 spin_unlock_irqrestore(&rpc
->e_lock
, flags
);
213 /* Read error source and clear error status */
214 pci_read_config_dword(pdev
->port
, pos
+ PCI_ERR_ROOT_ERR_SRC
, &id
);
215 pci_write_config_dword(pdev
->port
, pos
+ PCI_ERR_ROOT_STATUS
, status
);
217 /* Store error source for later DPC handler */
218 next_prod_idx
= rpc
->prod_idx
+ 1;
219 if (next_prod_idx
== AER_ERROR_SOURCES_MAX
)
221 if (next_prod_idx
== rpc
->cons_idx
) {
223 * Error Storm Condition - possibly the same error occurred.
226 spin_unlock_irqrestore(&rpc
->e_lock
, flags
);
229 rpc
->e_sources
[rpc
->prod_idx
].status
= status
;
230 rpc
->e_sources
[rpc
->prod_idx
].id
= id
;
231 rpc
->prod_idx
= next_prod_idx
;
232 spin_unlock_irqrestore(&rpc
->e_lock
, flags
);
234 /* Invoke DPC handler */
235 schedule_work(&rpc
->dpc_handler
);
239 EXPORT_SYMBOL_GPL(aer_irq
);
242 * aer_alloc_rpc - allocate Root Port data structure
243 * @dev: pointer to the pcie_dev data structure
245 * Invoked when Root Port's AER service is loaded.
247 static struct aer_rpc
*aer_alloc_rpc(struct pcie_device
*dev
)
251 rpc
= kzalloc(sizeof(struct aer_rpc
), GFP_KERNEL
);
255 /* Initialize Root lock access, e_lock, to Root Error Status Reg */
256 spin_lock_init(&rpc
->e_lock
);
259 INIT_WORK(&rpc
->dpc_handler
, aer_isr
);
260 mutex_init(&rpc
->rpc_mutex
);
262 /* Use PCIe bus function to store rpc into PCIe device */
263 set_service_data(dev
, rpc
);
269 * aer_remove - clean up resources
270 * @dev: pointer to the pcie_dev data structure
272 * Invoked when PCI Express bus unloads or AER probe fails.
274 static void aer_remove(struct pcie_device
*dev
)
276 struct aer_rpc
*rpc
= get_service_data(dev
);
279 /* If register interrupt service, it must be free. */
281 free_irq(dev
->irq
, dev
);
283 flush_work(&rpc
->dpc_handler
);
284 aer_disable_rootport(rpc
);
286 set_service_data(dev
, NULL
);
291 * aer_probe - initialize resources
292 * @dev: pointer to the pcie_dev data structure
293 * @id: pointer to the service id data structure
295 * Invoked when PCI Express bus loads AER service driver.
297 static int aer_probe(struct pcie_device
*dev
)
301 struct device
*device
= &dev
->device
;
304 status
= aer_init(dev
);
308 /* Alloc rpc data structure */
309 rpc
= aer_alloc_rpc(dev
);
311 dev_printk(KERN_DEBUG
, device
, "alloc rpc failed\n");
316 /* Request IRQ ISR */
317 status
= request_irq(dev
->irq
, aer_irq
, IRQF_SHARED
, "aerdrv", dev
);
319 dev_printk(KERN_DEBUG
, device
, "request IRQ failed\n");
326 aer_enable_rootport(rpc
);
332 * aer_root_reset - reset link on Root Port
333 * @dev: pointer to Root Port's pci_dev data structure
335 * Invoked by Port Bus driver when performing link reset at Root Port.
337 static pci_ers_result_t
aer_root_reset(struct pci_dev
*dev
)
342 pos
= pci_find_ext_capability(dev
, PCI_EXT_CAP_ID_ERR
);
344 /* Disable Root's interrupt in response to error messages */
345 pci_read_config_dword(dev
, pos
+ PCI_ERR_ROOT_COMMAND
, ®32
);
346 reg32
&= ~ROOT_PORT_INTR_ON_MESG_MASK
;
347 pci_write_config_dword(dev
, pos
+ PCI_ERR_ROOT_COMMAND
, reg32
);
349 pci_reset_bridge_secondary_bus(dev
);
350 dev_printk(KERN_DEBUG
, &dev
->dev
, "Root Port link has been reset\n");
352 /* Clear Root Error Status */
353 pci_read_config_dword(dev
, pos
+ PCI_ERR_ROOT_STATUS
, ®32
);
354 pci_write_config_dword(dev
, pos
+ PCI_ERR_ROOT_STATUS
, reg32
);
356 /* Enable Root Port's interrupt in response to error messages */
357 pci_read_config_dword(dev
, pos
+ PCI_ERR_ROOT_COMMAND
, ®32
);
358 reg32
|= ROOT_PORT_INTR_ON_MESG_MASK
;
359 pci_write_config_dword(dev
, pos
+ PCI_ERR_ROOT_COMMAND
, reg32
);
361 return PCI_ERS_RESULT_RECOVERED
;
365 * aer_error_detected - update severity status
366 * @dev: pointer to Root Port's pci_dev data structure
367 * @error: error severity being notified by port bus
369 * Invoked by Port Bus driver during error recovery.
371 static pci_ers_result_t
aer_error_detected(struct pci_dev
*dev
,
372 enum pci_channel_state error
)
374 /* Root Port has no impact. Always recovers. */
375 return PCI_ERS_RESULT_CAN_RECOVER
;
379 * aer_error_resume - clean up corresponding error status bits
380 * @dev: pointer to Root Port's pci_dev data structure
382 * Invoked by Port Bus driver during nonfatal recovery.
384 static void aer_error_resume(struct pci_dev
*dev
)
390 /* Clean up Root device status */
391 pcie_capability_read_word(dev
, PCI_EXP_DEVSTA
, ®16
);
392 pcie_capability_write_word(dev
, PCI_EXP_DEVSTA
, reg16
);
394 /* Clean AER Root Error Status */
395 pos
= pci_find_ext_capability(dev
, PCI_EXT_CAP_ID_ERR
);
396 pci_read_config_dword(dev
, pos
+ PCI_ERR_UNCOR_STATUS
, &status
);
397 pci_read_config_dword(dev
, pos
+ PCI_ERR_UNCOR_SEVER
, &mask
);
398 if (dev
->error_state
== pci_channel_io_normal
)
399 status
&= ~mask
; /* Clear corresponding nonfatal bits */
401 status
&= mask
; /* Clear corresponding fatal bits */
402 pci_write_config_dword(dev
, pos
+ PCI_ERR_UNCOR_STATUS
, status
);
406 * aer_service_init - register AER root service driver
408 * Invoked when AER root service driver is loaded.
410 static int __init
aer_service_init(void)
412 if (!pci_aer_available() || aer_acpi_firmware_first())
414 return pcie_port_service_register(&aerdriver
);
416 device_initcall(aer_service_init
);