2 * PCI Error Recovery Driver for RPA-compliant PPC64 platform.
3 * Copyright IBM Corp. 2004 2005
4 * Copyright Linas Vepstas <linas@linas.org> 2004, 2005
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or (at
11 * your option) any later version.
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
16 * NON INFRINGEMENT. See the GNU General Public License for more
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 * Send comments and feedback to Linas Vepstas <linas@austin.ibm.com>
25 #include <linux/delay.h>
26 #include <linux/interrupt.h>
27 #include <linux/irq.h>
28 #include <linux/pci.h>
30 #include <asm/eeh_event.h>
31 #include <asm/ppc-pci.h>
32 #include <asm/pci-bridge.h>
37 static inline const char * pcid_name (struct pci_dev
*pdev
)
39 if (pdev
&& pdev
->dev
.driver
)
40 return pdev
->dev
.driver
->name
;
45 static void print_device_node_tree(struct pci_dn
*pdn
, int dent
)
48 struct device_node
*pc
;
52 for (i
= 0; i
< dent
; i
++)
54 printk("dn=%s mode=%x \tcfg_addr=%x pe_addr=%x \tfull=%s\n",
55 pdn
->node
->name
, pdn
->eeh_mode
, pdn
->eeh_config_addr
,
56 pdn
->eeh_pe_config_addr
, pdn
->node
->full_name
);
58 pc
= pdn
->node
->child
;
60 print_device_node_tree(PCI_DN(pc
), dent
);
67 * irq_in_use - return true if this irq is being used
69 static int irq_in_use(unsigned int irq
)
73 struct irq_desc
*desc
= irq_desc
+ irq
;
75 spin_lock_irqsave(&desc
->lock
, flags
);
78 spin_unlock_irqrestore(&desc
->lock
, flags
);
82 /* ------------------------------------------------------- */
84 * eeh_report_error - report pci error to each device driver
86 * Report an EEH error to each device driver, collect up and
87 * merge the device driver responses. Cumulative response
88 * passed back in "userdata".
91 static void eeh_report_error(struct pci_dev
*dev
, void *userdata
)
93 enum pci_ers_result rc
, *res
= userdata
;
94 struct pci_driver
*driver
= dev
->driver
;
96 dev
->error_state
= pci_channel_io_frozen
;
101 if (irq_in_use (dev
->irq
)) {
102 struct device_node
*dn
= pci_device_to_OF_node(dev
);
103 PCI_DN(dn
)->eeh_mode
|= EEH_MODE_IRQ_DISABLED
;
104 disable_irq_nosync(dev
->irq
);
106 if (!driver
->err_handler
||
107 !driver
->err_handler
->error_detected
)
110 rc
= driver
->err_handler
->error_detected (dev
, pci_channel_io_frozen
);
112 /* A driver that needs a reset trumps all others */
113 if (rc
== PCI_ERS_RESULT_NEED_RESET
) *res
= rc
;
114 if (*res
== PCI_ERS_RESULT_NONE
) *res
= rc
;
118 * eeh_report_mmio_enabled - tell drivers that MMIO has been enabled
120 * Tells each device driver that IO ports, MMIO and config space I/O
121 * are now enabled. Collects up and merges the device driver responses.
122 * Cumulative response passed back in "userdata".
125 static void eeh_report_mmio_enabled(struct pci_dev
*dev
, void *userdata
)
127 enum pci_ers_result rc
, *res
= userdata
;
128 struct pci_driver
*driver
= dev
->driver
;
131 !driver
->err_handler
||
132 !driver
->err_handler
->mmio_enabled
)
135 rc
= driver
->err_handler
->mmio_enabled (dev
);
137 /* A driver that needs a reset trumps all others */
138 if (rc
== PCI_ERS_RESULT_NEED_RESET
) *res
= rc
;
139 if (*res
== PCI_ERS_RESULT_NONE
) *res
= rc
;
143 * eeh_report_reset - tell device that slot has been reset
146 static void eeh_report_reset(struct pci_dev
*dev
, void *userdata
)
148 enum pci_ers_result rc
, *res
= userdata
;
149 struct pci_driver
*driver
= dev
->driver
;
150 struct device_node
*dn
= pci_device_to_OF_node(dev
);
155 if ((PCI_DN(dn
)->eeh_mode
) & EEH_MODE_IRQ_DISABLED
) {
156 PCI_DN(dn
)->eeh_mode
&= ~EEH_MODE_IRQ_DISABLED
;
157 enable_irq(dev
->irq
);
159 if (!driver
->err_handler
||
160 !driver
->err_handler
->slot_reset
)
163 rc
= driver
->err_handler
->slot_reset(dev
);
164 if ((*res
== PCI_ERS_RESULT_NONE
) ||
165 (*res
== PCI_ERS_RESULT_RECOVERED
)) *res
= rc
;
166 if (*res
== PCI_ERS_RESULT_DISCONNECT
&&
167 rc
== PCI_ERS_RESULT_NEED_RESET
) *res
= rc
;
171 * eeh_report_resume - tell device to resume normal operations
174 static void eeh_report_resume(struct pci_dev
*dev
, void *userdata
)
176 struct pci_driver
*driver
= dev
->driver
;
177 struct device_node
*dn
= pci_device_to_OF_node(dev
);
179 dev
->error_state
= pci_channel_io_normal
;
184 if ((PCI_DN(dn
)->eeh_mode
) & EEH_MODE_IRQ_DISABLED
) {
185 PCI_DN(dn
)->eeh_mode
&= ~EEH_MODE_IRQ_DISABLED
;
186 enable_irq(dev
->irq
);
188 if (!driver
->err_handler
||
189 !driver
->err_handler
->resume
)
192 driver
->err_handler
->resume(dev
);
196 * eeh_report_failure - tell device driver that device is dead.
198 * This informs the device driver that the device is permanently
199 * dead, and that no further recovery attempts will be made on it.
202 static void eeh_report_failure(struct pci_dev
*dev
, void *userdata
)
204 struct pci_driver
*driver
= dev
->driver
;
206 dev
->error_state
= pci_channel_io_perm_failure
;
211 if (irq_in_use (dev
->irq
)) {
212 struct device_node
*dn
= pci_device_to_OF_node(dev
);
213 PCI_DN(dn
)->eeh_mode
|= EEH_MODE_IRQ_DISABLED
;
214 disable_irq_nosync(dev
->irq
);
216 if (!driver
->err_handler
)
218 if (!driver
->err_handler
->error_detected
)
220 driver
->err_handler
->error_detected(dev
, pci_channel_io_perm_failure
);
223 /* ------------------------------------------------------- */
225 * handle_eeh_events -- reset a PCI device after hard lockup.
227 * pSeries systems will isolate a PCI slot if the PCI-Host
228 * bridge detects address or data parity errors, DMA's
229 * occurring to wild addresses (which usually happen due to
230 * bugs in device drivers or in PCI adapter firmware).
231 * Slot isolations also occur if #SERR, #PERR or other misc
232 * PCI-related errors are detected.
234 * Recovery process consists of unplugging the device driver
235 * (which generated hotplug events to userspace), then issuing
236 * a PCI #RST to the device, then reconfiguring the PCI config
237 * space for all bridges & devices under this slot, and then
238 * finally restarting the device drivers (which cause a second
239 * set of hotplug events to go out to userspace).
243 * eeh_reset_device() -- perform actual reset of a pci slot
244 * @bus: pointer to the pci bus structure corresponding
245 * to the isolated slot. A non-null value will
246 * cause all devices under the bus to be removed
248 * @pe_dn: pointer to a "Partionable Endpoint" device node.
249 * This is the top-level structure on which pci
250 * bus resets can be performed.
253 static int eeh_reset_device (struct pci_dn
*pe_dn
, struct pci_bus
*bus
)
255 struct device_node
*dn
;
258 /* pcibios will clear the counter; save the value */
259 cnt
= pe_dn
->eeh_freeze_count
;
262 pcibios_remove_pci_devices(bus
);
264 /* Reset the pci controller. (Asserts RST#; resets config space).
265 * Reconfigure bridges and devices. Don't try to bring the system
266 * up if the reset failed for some reason. */
267 rc
= rtas_set_slot_reset(pe_dn
);
271 /* Walk over all functions on this device. */
273 if (!pcibios_find_pci_bus(dn
) && PCI_DN(dn
->parent
))
274 dn
= dn
->parent
->child
;
277 struct pci_dn
*ppe
= PCI_DN(dn
);
278 /* On Power4, always true because eeh_pe_config_addr=0 */
279 if (pe_dn
->eeh_pe_config_addr
== ppe
->eeh_pe_config_addr
) {
280 rtas_configure_bridge(ppe
);
281 eeh_restore_bars(ppe
);
286 /* Give the system 5 seconds to finish running the user-space
287 * hotplug shutdown scripts, e.g. ifdown for ethernet. Yes,
288 * this is a hack, but if we don't do this, and try to bring
289 * the device up before the scripts have taken it down,
290 * potentially weird things happen.
294 pcibios_add_pci_devices(bus
);
296 pe_dn
->eeh_freeze_count
= cnt
;
301 /* The longest amount of time to wait for a pci device
302 * to come back on line, in seconds.
304 #define MAX_WAIT_FOR_RECOVERY 150
306 struct pci_dn
* handle_eeh_events (struct eeh_event
*event
)
308 struct device_node
*frozen_dn
;
309 struct pci_dn
*frozen_pdn
;
310 struct pci_bus
*frozen_bus
;
312 enum pci_ers_result result
= PCI_ERS_RESULT_NONE
;
313 const char *location
, *pci_str
, *drv_str
;
315 frozen_dn
= find_device_pe(event
->dn
);
318 location
= of_get_property(event
->dn
, "ibm,loc-code", NULL
);
319 location
= location
? location
: "unknown";
320 printk(KERN_ERR
"EEH: Error: Cannot find partition endpoint "
321 "for location=%s pci addr=%s\n",
322 location
, pci_name(event
->dev
));
326 frozen_bus
= pcibios_find_pci_bus(frozen_dn
);
327 location
= of_get_property(frozen_dn
, "ibm,loc-code", NULL
);
328 location
= location
? location
: "unknown";
330 /* There are two different styles for coming up with the PE.
331 * In the old style, it was the highest EEH-capable device
332 * which was always an EADS pci bridge. In the new style,
333 * there might not be any EADS bridges, and even when there are,
334 * the firmware marks them as "EEH incapable". So another
335 * two-step is needed to find the pci bus.. */
337 frozen_bus
= pcibios_find_pci_bus (frozen_dn
->parent
);
340 printk(KERN_ERR
"EEH: Cannot find PCI bus "
341 "for location=%s dn=%s\n",
342 location
, frozen_dn
->full_name
);
346 frozen_pdn
= PCI_DN(frozen_dn
);
347 frozen_pdn
->eeh_freeze_count
++;
349 if (frozen_pdn
->pcidev
) {
350 pci_str
= pci_name (frozen_pdn
->pcidev
);
351 drv_str
= pcid_name (frozen_pdn
->pcidev
);
353 pci_str
= pci_name (event
->dev
);
354 drv_str
= pcid_name (event
->dev
);
357 if (frozen_pdn
->eeh_freeze_count
> EEH_MAX_ALLOWED_FREEZES
)
358 goto excess_failures
;
361 "EEH: This PCI device has failed %d times in the last hour:\n",
362 frozen_pdn
->eeh_freeze_count
);
364 "EEH: location=%s driver=%s pci addr=%s\n",
365 location
, drv_str
, pci_str
);
367 /* Walk the various device drivers attached to this slot through
368 * a reset sequence, giving each an opportunity to do what it needs
369 * to accomplish the reset. Each child gets a report of the
370 * status ... if any child can't handle the reset, then the entire
371 * slot is dlpar removed and added.
373 pci_walk_bus(frozen_bus
, eeh_report_error
, &result
);
375 /* Get the current PCI slot state. This can take a long time,
376 * sometimes over 3 seconds for certain systems. */
377 rc
= eeh_wait_for_slot_status (frozen_pdn
, MAX_WAIT_FOR_RECOVERY
*1000);
379 printk(KERN_WARNING
"EEH: Permanent failure\n");
383 /* Since rtas may enable MMIO when posting the error log,
384 * don't post the error log until after all dev drivers
385 * have been informed.
387 eeh_slot_error_detail(frozen_pdn
, EEH_LOG_TEMP_FAILURE
);
389 /* If all device drivers were EEH-unaware, then shut
390 * down all of the device drivers, and hope they
391 * go down willingly, without panicing the system.
393 if (result
== PCI_ERS_RESULT_NONE
) {
394 rc
= eeh_reset_device(frozen_pdn
, frozen_bus
);
396 printk(KERN_WARNING
"EEH: Unable to reset, rc=%d\n", rc
);
401 /* If all devices reported they can proceed, then re-enable MMIO */
402 if (result
== PCI_ERS_RESULT_CAN_RECOVER
) {
403 rc
= rtas_pci_enable(frozen_pdn
, EEH_THAW_MMIO
);
408 result
= PCI_ERS_RESULT_NEED_RESET
;
410 result
= PCI_ERS_RESULT_NONE
;
411 pci_walk_bus(frozen_bus
, eeh_report_mmio_enabled
, &result
);
415 /* If all devices reported they can proceed, then re-enable DMA */
416 if (result
== PCI_ERS_RESULT_CAN_RECOVER
) {
417 rc
= rtas_pci_enable(frozen_pdn
, EEH_THAW_DMA
);
422 result
= PCI_ERS_RESULT_NEED_RESET
;
424 result
= PCI_ERS_RESULT_RECOVERED
;
427 /* If any device has a hard failure, then shut off everything. */
428 if (result
== PCI_ERS_RESULT_DISCONNECT
) {
429 printk(KERN_WARNING
"EEH: Device driver gave up\n");
433 /* If any device called out for a reset, then reset the slot */
434 if (result
== PCI_ERS_RESULT_NEED_RESET
) {
435 rc
= eeh_reset_device(frozen_pdn
, NULL
);
437 printk(KERN_WARNING
"EEH: Cannot reset, rc=%d\n", rc
);
440 result
= PCI_ERS_RESULT_NONE
;
441 pci_walk_bus(frozen_bus
, eeh_report_reset
, &result
);
444 /* All devices should claim they have recovered by now. */
445 if ((result
!= PCI_ERS_RESULT_RECOVERED
) &&
446 (result
!= PCI_ERS_RESULT_NONE
)) {
447 printk(KERN_WARNING
"EEH: Not recovered\n");
451 /* Tell all device drivers that they can resume operations */
452 pci_walk_bus(frozen_bus
, eeh_report_resume
, NULL
);
458 * About 90% of all real-life EEH failures in the field
459 * are due to poorly seated PCI cards. Only 10% or so are
460 * due to actual, failed cards.
463 "EEH: PCI device at location=%s driver=%s pci addr=%s \n"
464 "has failed %d times in the last hour "
465 "and has been permanently disabled. \n"
466 "Please try reseating this device or replacing it.\n",
467 location
, drv_str
, pci_str
, frozen_pdn
->eeh_freeze_count
);
472 "EEH: Unable to recover from failure of PCI device "
473 "at location=%s driver=%s pci addr=%s \n"
474 "Please try reseating this device or replacing it.\n",
475 location
, drv_str
, pci_str
);
478 eeh_slot_error_detail(frozen_pdn
, EEH_LOG_PERM_FAILURE
);
480 /* Notify all devices that they're about to go down. */
481 pci_walk_bus(frozen_bus
, eeh_report_failure
, NULL
);
483 /* Shut down the device drivers for good. */
484 pcibios_remove_pci_devices(frozen_bus
);
489 /* ---------- end of file ---------- */