1 /*
2  * The file intends to implement the platform dependent EEH operations on pseries.
3  * Actually, the pseries platform is built based on RTAS heavily. That means the
4  * pseries platform dependent EEH operations will be built on RTAS calls. The functions
5  * are devired from arch/powerpc/platforms/pseries/eeh.c and necessary cleanup has
6  * been done.
7  *
8  * Copyright Benjamin Herrenschmidt & Gavin Shan, IBM Corporation 2011.
9  * Copyright IBM Corporation 2001, 2005, 2006
10  * Copyright Dave Engebretsen & Todd Inglett 2001
11  * Copyright Linas Vepstas 2005, 2006
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License as published by
15  * the Free Software Foundation; either version 2 of the License, or
16  * (at your option) any later version.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  * GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with this program; if not, write to the Free Software
25  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
26  */
27 
28 #include <linux/atomic.h>
29 #include <linux/delay.h>
30 #include <linux/export.h>
31 #include <linux/init.h>
32 #include <linux/list.h>
33 #include <linux/of.h>
34 #include <linux/pci.h>
35 #include <linux/proc_fs.h>
36 #include <linux/rbtree.h>
37 #include <linux/sched.h>
38 #include <linux/seq_file.h>
39 #include <linux/spinlock.h>
40 
41 #include <asm/eeh.h>
42 #include <asm/eeh_event.h>
43 #include <asm/io.h>
44 #include <asm/machdep.h>
45 #include <asm/ppc-pci.h>
46 #include <asm/rtas.h>
47 
48 /* RTAS tokens */
49 static int ibm_set_eeh_option;
50 static int ibm_set_slot_reset;
51 static int ibm_read_slot_reset_state;
52 static int ibm_read_slot_reset_state2;
53 static int ibm_slot_error_detail;
54 static int ibm_get_config_addr_info;
55 static int ibm_get_config_addr_info2;
56 static int ibm_configure_bridge;
57 static int ibm_configure_pe;
58 
59 /*
60  * Buffer for reporting slot-error-detail rtas calls. Its here
61  * in BSS, and not dynamically alloced, so that it ends up in
62  * RMO where RTAS can access it.
63  */
64 static unsigned char slot_errbuf[RTAS_ERROR_LOG_MAX];
65 static DEFINE_SPINLOCK(slot_errbuf_lock);
66 static int eeh_error_buf_size;
67 
68 /**
69  * pseries_eeh_init - EEH platform dependent initialization
70  *
71  * EEH platform dependent initialization on pseries.
72  */
73 static int pseries_eeh_init(void)
74 {
75 	/* figure out EEH RTAS function call tokens */
76 	ibm_set_eeh_option		= rtas_token("ibm,set-eeh-option");
77 	ibm_set_slot_reset		= rtas_token("ibm,set-slot-reset");
78 	ibm_read_slot_reset_state2	= rtas_token("ibm,read-slot-reset-state2");
79 	ibm_read_slot_reset_state	= rtas_token("ibm,read-slot-reset-state");
80 	ibm_slot_error_detail		= rtas_token("ibm,slot-error-detail");
81 	ibm_get_config_addr_info2	= rtas_token("ibm,get-config-addr-info2");
82 	ibm_get_config_addr_info	= rtas_token("ibm,get-config-addr-info");
83 	ibm_configure_pe		= rtas_token("ibm,configure-pe");
84 	ibm_configure_bridge		= rtas_token("ibm,configure-bridge");
85 
86 	/*
87 	 * Necessary sanity check. We needn't check "get-config-addr-info"
88 	 * and its variant since the old firmware probably support address
89 	 * of domain/bus/slot/function for EEH RTAS operations.
90 	 */
91 	if (ibm_set_eeh_option == RTAS_UNKNOWN_SERVICE		||
92 	    ibm_set_slot_reset == RTAS_UNKNOWN_SERVICE		||
93 	    (ibm_read_slot_reset_state2 == RTAS_UNKNOWN_SERVICE &&
94 	     ibm_read_slot_reset_state == RTAS_UNKNOWN_SERVICE)	||
95 	    ibm_slot_error_detail == RTAS_UNKNOWN_SERVICE	||
96 	    (ibm_configure_pe == RTAS_UNKNOWN_SERVICE		&&
97 	     ibm_configure_bridge == RTAS_UNKNOWN_SERVICE)) {
98 		pr_info("EEH functionality not supported\n");
99 		return -EINVAL;
100 	}
101 
102 	/* Initialize error log lock and size */
103 	spin_lock_init(&slot_errbuf_lock);
104 	eeh_error_buf_size = rtas_token("rtas-error-log-max");
105 	if (eeh_error_buf_size == RTAS_UNKNOWN_SERVICE) {
106 		pr_info("%s: unknown EEH error log size\n",
107 			__func__);
108 		eeh_error_buf_size = 1024;
109 	} else if (eeh_error_buf_size > RTAS_ERROR_LOG_MAX) {
110 		pr_info("%s: EEH error log size %d exceeds the maximal %d\n",
111 			__func__, eeh_error_buf_size, RTAS_ERROR_LOG_MAX);
112 		eeh_error_buf_size = RTAS_ERROR_LOG_MAX;
113 	}
114 
115 	/* Set EEH probe mode */
116 	eeh_add_flag(EEH_PROBE_MODE_DEVTREE | EEH_ENABLE_IO_FOR_LOG);
117 
118 	return 0;
119 }
120 
121 static int pseries_eeh_cap_start(struct pci_dn *pdn)
122 {
123 	u32 status;
124 
125 	if (!pdn)
126 		return 0;
127 
128 	rtas_read_config(pdn, PCI_STATUS, 2, &status);
129 	if (!(status & PCI_STATUS_CAP_LIST))
130 		return 0;
131 
132 	return PCI_CAPABILITY_LIST;
133 }
134 
135 
136 static int pseries_eeh_find_cap(struct pci_dn *pdn, int cap)
137 {
138 	int pos = pseries_eeh_cap_start(pdn);
139 	int cnt = 48;	/* Maximal number of capabilities */
140 	u32 id;
141 
142 	if (!pos)
143 		return 0;
144 
145         while (cnt--) {
146 		rtas_read_config(pdn, pos, 1, &pos);
147 		if (pos < 0x40)
148 			break;
149 		pos &= ~3;
150 		rtas_read_config(pdn, pos + PCI_CAP_LIST_ID, 1, &id);
151 		if (id == 0xff)
152 			break;
153 		if (id == cap)
154 			return pos;
155 		pos += PCI_CAP_LIST_NEXT;
156 	}
157 
158 	return 0;
159 }
160 
161 static int pseries_eeh_find_ecap(struct pci_dn *pdn, int cap)
162 {
163 	struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
164 	u32 header;
165 	int pos = 256;
166 	int ttl = (4096 - 256) / 8;
167 
168 	if (!edev || !edev->pcie_cap)
169 		return 0;
170 	if (rtas_read_config(pdn, pos, 4, &header) != PCIBIOS_SUCCESSFUL)
171 		return 0;
172 	else if (!header)
173 		return 0;
174 
175 	while (ttl-- > 0) {
176 		if (PCI_EXT_CAP_ID(header) == cap && pos)
177 			return pos;
178 
179 		pos = PCI_EXT_CAP_NEXT(header);
180 		if (pos < 256)
181 			break;
182 
183 		if (rtas_read_config(pdn, pos, 4, &header) != PCIBIOS_SUCCESSFUL)
184 			break;
185 	}
186 
187 	return 0;
188 }
189 
190 /**
191  * pseries_eeh_probe - EEH probe on the given device
192  * @pdn: PCI device node
193  * @data: Unused
194  *
195  * When EEH module is installed during system boot, all PCI devices
196  * are checked one by one to see if it supports EEH. The function
197  * is introduced for the purpose.
198  */
199 static void *pseries_eeh_probe(struct pci_dn *pdn, void *data)
200 {
201 	struct eeh_dev *edev;
202 	struct eeh_pe pe;
203 	u32 pcie_flags;
204 	int enable = 0;
205 	int ret;
206 
207 	/* Retrieve OF node and eeh device */
208 	edev = pdn_to_eeh_dev(pdn);
209 	if (!edev || edev->pe)
210 		return NULL;
211 
212 	/* Check class/vendor/device IDs */
213 	if (!pdn->vendor_id || !pdn->device_id || !pdn->class_code)
214 		return NULL;
215 
216 	/* Skip for PCI-ISA bridge */
217         if ((pdn->class_code >> 8) == PCI_CLASS_BRIDGE_ISA)
218 		return NULL;
219 
220 	/*
221 	 * Update class code and mode of eeh device. We need
222 	 * correctly reflects that current device is root port
223 	 * or PCIe switch downstream port.
224 	 */
225 	edev->class_code = pdn->class_code;
226 	edev->pcix_cap = pseries_eeh_find_cap(pdn, PCI_CAP_ID_PCIX);
227 	edev->pcie_cap = pseries_eeh_find_cap(pdn, PCI_CAP_ID_EXP);
228 	edev->aer_cap = pseries_eeh_find_ecap(pdn, PCI_EXT_CAP_ID_ERR);
229 	edev->mode &= 0xFFFFFF00;
230 	if ((edev->class_code >> 8) == PCI_CLASS_BRIDGE_PCI) {
231 		edev->mode |= EEH_DEV_BRIDGE;
232 		if (edev->pcie_cap) {
233 			rtas_read_config(pdn, edev->pcie_cap + PCI_EXP_FLAGS,
234 					 2, &pcie_flags);
235 			pcie_flags = (pcie_flags & PCI_EXP_FLAGS_TYPE) >> 4;
236 			if (pcie_flags == PCI_EXP_TYPE_ROOT_PORT)
237 				edev->mode |= EEH_DEV_ROOT_PORT;
238 			else if (pcie_flags == PCI_EXP_TYPE_DOWNSTREAM)
239 				edev->mode |= EEH_DEV_DS_PORT;
240 		}
241 	}
242 
243 	/* Initialize the fake PE */
244 	memset(&pe, 0, sizeof(struct eeh_pe));
245 	pe.phb = edev->phb;
246 	pe.config_addr = (pdn->busno << 16) | (pdn->devfn << 8);
247 
248 	/* Enable EEH on the device */
249 	ret = eeh_ops->set_option(&pe, EEH_OPT_ENABLE);
250 	if (!ret) {
251 		/* Retrieve PE address */
252 		edev->config_addr = (pdn->busno << 16) | (pdn->devfn << 8);
253 		edev->pe_config_addr = eeh_ops->get_pe_addr(&pe);
254 		pe.addr = edev->pe_config_addr;
255 
256 		/* Some older systems (Power4) allow the ibm,set-eeh-option
257 		 * call to succeed even on nodes where EEH is not supported.
258 		 * Verify support explicitly.
259 		 */
260 		ret = eeh_ops->get_state(&pe, NULL);
261 		if (ret > 0 && ret != EEH_STATE_NOT_SUPPORT)
262 			enable = 1;
263 
264 		if (enable) {
265 			eeh_add_flag(EEH_ENABLED);
266 			eeh_add_to_parent_pe(edev);
267 
268 			pr_debug("%s: EEH enabled on %02x:%02x.%01x PHB#%d-PE#%x\n",
269 				__func__, pdn->busno, PCI_SLOT(pdn->devfn),
270 				PCI_FUNC(pdn->devfn), pe.phb->global_number,
271 				pe.addr);
272 		} else if (pdn->parent && pdn_to_eeh_dev(pdn->parent) &&
273 			   (pdn_to_eeh_dev(pdn->parent))->pe) {
274 			/* This device doesn't support EEH, but it may have an
275 			 * EEH parent, in which case we mark it as supported.
276 			 */
277 			edev->config_addr = pdn_to_eeh_dev(pdn->parent)->config_addr;
278 			edev->pe_config_addr = pdn_to_eeh_dev(pdn->parent)->pe_config_addr;
279 			eeh_add_to_parent_pe(edev);
280 		}
281 	}
282 
283 	/* Save memory bars */
284 	eeh_save_bars(edev);
285 
286 	return NULL;
287 }
288 
289 /**
290  * pseries_eeh_set_option - Initialize EEH or MMIO/DMA reenable
291  * @pe: EEH PE
292  * @option: operation to be issued
293  *
294  * The function is used to control the EEH functionality globally.
295  * Currently, following options are support according to PAPR:
296  * Enable EEH, Disable EEH, Enable MMIO and Enable DMA
297  */
298 static int pseries_eeh_set_option(struct eeh_pe *pe, int option)
299 {
300 	int ret = 0;
301 	int config_addr;
302 
303 	/*
304 	 * When we're enabling or disabling EEH functioality on
305 	 * the particular PE, the PE config address is possibly
306 	 * unavailable. Therefore, we have to figure it out from
307 	 * the FDT node.
308 	 */
309 	switch (option) {
310 	case EEH_OPT_DISABLE:
311 	case EEH_OPT_ENABLE:
312 	case EEH_OPT_THAW_MMIO:
313 	case EEH_OPT_THAW_DMA:
314 		config_addr = pe->config_addr;
315 		if (pe->addr)
316 			config_addr = pe->addr;
317 		break;
318 	case EEH_OPT_FREEZE_PE:
319 		/* Not support */
320 		return 0;
321 	default:
322 		pr_err("%s: Invalid option %d\n",
323 			__func__, option);
324 		return -EINVAL;
325 	}
326 
327 	ret = rtas_call(ibm_set_eeh_option, 4, 1, NULL,
328 			config_addr, BUID_HI(pe->phb->buid),
329 			BUID_LO(pe->phb->buid), option);
330 
331 	return ret;
332 }
333 
334 /**
335  * pseries_eeh_get_pe_addr - Retrieve PE address
336  * @pe: EEH PE
337  *
338  * Retrieve the assocated PE address. Actually, there're 2 RTAS
339  * function calls dedicated for the purpose. We need implement
340  * it through the new function and then the old one. Besides,
341  * you should make sure the config address is figured out from
342  * FDT node before calling the function.
343  *
344  * It's notable that zero'ed return value means invalid PE config
345  * address.
346  */
347 static int pseries_eeh_get_pe_addr(struct eeh_pe *pe)
348 {
349 	int ret = 0;
350 	int rets[3];
351 
352 	if (ibm_get_config_addr_info2 != RTAS_UNKNOWN_SERVICE) {
353 		/*
354 		 * First of all, we need to make sure there has one PE
355 		 * associated with the device. Otherwise, PE address is
356 		 * meaningless.
357 		 */
358 		ret = rtas_call(ibm_get_config_addr_info2, 4, 2, rets,
359 				pe->config_addr, BUID_HI(pe->phb->buid),
360 				BUID_LO(pe->phb->buid), 1);
361 		if (ret || (rets[0] == 0))
362 			return 0;
363 
364 		/* Retrieve the associated PE config address */
365 		ret = rtas_call(ibm_get_config_addr_info2, 4, 2, rets,
366 				pe->config_addr, BUID_HI(pe->phb->buid),
367 				BUID_LO(pe->phb->buid), 0);
368 		if (ret) {
369 			pr_warn("%s: Failed to get address for PHB#%d-PE#%x\n",
370 				__func__, pe->phb->global_number, pe->config_addr);
371 			return 0;
372 		}
373 
374 		return rets[0];
375 	}
376 
377 	if (ibm_get_config_addr_info != RTAS_UNKNOWN_SERVICE) {
378 		ret = rtas_call(ibm_get_config_addr_info, 4, 2, rets,
379 				pe->config_addr, BUID_HI(pe->phb->buid),
380 				BUID_LO(pe->phb->buid), 0);
381 		if (ret) {
382 			pr_warn("%s: Failed to get address for PHB#%d-PE#%x\n",
383 				__func__, pe->phb->global_number, pe->config_addr);
384 			return 0;
385 		}
386 
387 		return rets[0];
388 	}
389 
390 	return ret;
391 }
392 
393 /**
394  * pseries_eeh_get_state - Retrieve PE state
395  * @pe: EEH PE
396  * @state: return value
397  *
398  * Retrieve the state of the specified PE. On RTAS compliant
399  * pseries platform, there already has one dedicated RTAS function
400  * for the purpose. It's notable that the associated PE config address
401  * might be ready when calling the function. Therefore, endeavour to
402  * use the PE config address if possible. Further more, there're 2
403  * RTAS calls for the purpose, we need to try the new one and back
404  * to the old one if the new one couldn't work properly.
405  */
406 static int pseries_eeh_get_state(struct eeh_pe *pe, int *state)
407 {
408 	int config_addr;
409 	int ret;
410 	int rets[4];
411 	int result;
412 
413 	/* Figure out PE config address if possible */
414 	config_addr = pe->config_addr;
415 	if (pe->addr)
416 		config_addr = pe->addr;
417 
418 	if (ibm_read_slot_reset_state2 != RTAS_UNKNOWN_SERVICE) {
419 		ret = rtas_call(ibm_read_slot_reset_state2, 3, 4, rets,
420 				config_addr, BUID_HI(pe->phb->buid),
421 				BUID_LO(pe->phb->buid));
422 	} else if (ibm_read_slot_reset_state != RTAS_UNKNOWN_SERVICE) {
423 		/* Fake PE unavailable info */
424 		rets[2] = 0;
425 		ret = rtas_call(ibm_read_slot_reset_state, 3, 3, rets,
426 				config_addr, BUID_HI(pe->phb->buid),
427 				BUID_LO(pe->phb->buid));
428 	} else {
429 		return EEH_STATE_NOT_SUPPORT;
430 	}
431 
432 	if (ret)
433 		return ret;
434 
435 	/* Parse the result out */
436 	result = 0;
437 	if (rets[1]) {
438 		switch(rets[0]) {
439 		case 0:
440 			result &= ~EEH_STATE_RESET_ACTIVE;
441 			result |= EEH_STATE_MMIO_ACTIVE;
442 			result |= EEH_STATE_DMA_ACTIVE;
443 			break;
444 		case 1:
445 			result |= EEH_STATE_RESET_ACTIVE;
446 			result |= EEH_STATE_MMIO_ACTIVE;
447 			result |= EEH_STATE_DMA_ACTIVE;
448 			break;
449 		case 2:
450 			result &= ~EEH_STATE_RESET_ACTIVE;
451 			result &= ~EEH_STATE_MMIO_ACTIVE;
452 			result &= ~EEH_STATE_DMA_ACTIVE;
453 			break;
454 		case 4:
455 			result &= ~EEH_STATE_RESET_ACTIVE;
456 			result &= ~EEH_STATE_MMIO_ACTIVE;
457 			result &= ~EEH_STATE_DMA_ACTIVE;
458 			result |= EEH_STATE_MMIO_ENABLED;
459 			break;
460 		case 5:
461 			if (rets[2]) {
462 				if (state) *state = rets[2];
463 				result = EEH_STATE_UNAVAILABLE;
464 			} else {
465 				result = EEH_STATE_NOT_SUPPORT;
466 			}
467 			break;
468 		default:
469 			result = EEH_STATE_NOT_SUPPORT;
470 		}
471 	} else {
472 		result = EEH_STATE_NOT_SUPPORT;
473 	}
474 
475 	return result;
476 }
477 
478 /**
479  * pseries_eeh_reset - Reset the specified PE
480  * @pe: EEH PE
481  * @option: reset option
482  *
483  * Reset the specified PE
484  */
485 static int pseries_eeh_reset(struct eeh_pe *pe, int option)
486 {
487 	int config_addr;
488 	int ret;
489 
490 	/* Figure out PE address */
491 	config_addr = pe->config_addr;
492 	if (pe->addr)
493 		config_addr = pe->addr;
494 
495 	/* Reset PE through RTAS call */
496 	ret = rtas_call(ibm_set_slot_reset, 4, 1, NULL,
497 			config_addr, BUID_HI(pe->phb->buid),
498 			BUID_LO(pe->phb->buid), option);
499 
500 	/* If fundamental-reset not supported, try hot-reset */
501 	if (option == EEH_RESET_FUNDAMENTAL &&
502 	    ret == -8) {
503 		option = EEH_RESET_HOT;
504 		ret = rtas_call(ibm_set_slot_reset, 4, 1, NULL,
505 				config_addr, BUID_HI(pe->phb->buid),
506 				BUID_LO(pe->phb->buid), option);
507 	}
508 
509 	/* We need reset hold or settlement delay */
510 	if (option == EEH_RESET_FUNDAMENTAL ||
511 	    option == EEH_RESET_HOT)
512 		msleep(EEH_PE_RST_HOLD_TIME);
513 	else
514 		msleep(EEH_PE_RST_SETTLE_TIME);
515 
516 	return ret;
517 }
518 
519 /**
520  * pseries_eeh_wait_state - Wait for PE state
521  * @pe: EEH PE
522  * @max_wait: maximal period in microsecond
523  *
524  * Wait for the state of associated PE. It might take some time
525  * to retrieve the PE's state.
526  */
527 static int pseries_eeh_wait_state(struct eeh_pe *pe, int max_wait)
528 {
529 	int ret;
530 	int mwait;
531 
532 	/*
533 	 * According to PAPR, the state of PE might be temporarily
534 	 * unavailable. Under the circumstance, we have to wait
535 	 * for indicated time determined by firmware. The maximal
536 	 * wait time is 5 minutes, which is acquired from the original
537 	 * EEH implementation. Also, the original implementation
538 	 * also defined the minimal wait time as 1 second.
539 	 */
540 #define EEH_STATE_MIN_WAIT_TIME	(1000)
541 #define EEH_STATE_MAX_WAIT_TIME	(300 * 1000)
542 
543 	while (1) {
544 		ret = pseries_eeh_get_state(pe, &mwait);
545 
546 		/*
547 		 * If the PE's state is temporarily unavailable,
548 		 * we have to wait for the specified time. Otherwise,
549 		 * the PE's state will be returned immediately.
550 		 */
551 		if (ret != EEH_STATE_UNAVAILABLE)
552 			return ret;
553 
554 		if (max_wait <= 0) {
555 			pr_warn("%s: Timeout when getting PE's state (%d)\n",
556 				__func__, max_wait);
557 			return EEH_STATE_NOT_SUPPORT;
558 		}
559 
560 		if (mwait <= 0) {
561 			pr_warn("%s: Firmware returned bad wait value %d\n",
562 				__func__, mwait);
563 			mwait = EEH_STATE_MIN_WAIT_TIME;
564 		} else if (mwait > EEH_STATE_MAX_WAIT_TIME) {
565 			pr_warn("%s: Firmware returned too long wait value %d\n",
566 				__func__, mwait);
567 			mwait = EEH_STATE_MAX_WAIT_TIME;
568 		}
569 
570 		max_wait -= mwait;
571 		msleep(mwait);
572 	}
573 
574 	return EEH_STATE_NOT_SUPPORT;
575 }
576 
577 /**
578  * pseries_eeh_get_log - Retrieve error log
579  * @pe: EEH PE
580  * @severity: temporary or permanent error log
581  * @drv_log: driver log to be combined with retrieved error log
582  * @len: length of driver log
583  *
584  * Retrieve the temporary or permanent error from the PE.
585  * Actually, the error will be retrieved through the dedicated
586  * RTAS call.
587  */
588 static int pseries_eeh_get_log(struct eeh_pe *pe, int severity, char *drv_log, unsigned long len)
589 {
590 	int config_addr;
591 	unsigned long flags;
592 	int ret;
593 
594 	spin_lock_irqsave(&slot_errbuf_lock, flags);
595 	memset(slot_errbuf, 0, eeh_error_buf_size);
596 
597 	/* Figure out the PE address */
598 	config_addr = pe->config_addr;
599 	if (pe->addr)
600 		config_addr = pe->addr;
601 
602 	ret = rtas_call(ibm_slot_error_detail, 8, 1, NULL, config_addr,
603 			BUID_HI(pe->phb->buid), BUID_LO(pe->phb->buid),
604 			virt_to_phys(drv_log), len,
605 			virt_to_phys(slot_errbuf), eeh_error_buf_size,
606 			severity);
607 	if (!ret)
608 		log_error(slot_errbuf, ERR_TYPE_RTAS_LOG, 0);
609 	spin_unlock_irqrestore(&slot_errbuf_lock, flags);
610 
611 	return ret;
612 }
613 
614 /**
615  * pseries_eeh_configure_bridge - Configure PCI bridges in the indicated PE
616  * @pe: EEH PE
617  *
618  * The function will be called to reconfigure the bridges included
619  * in the specified PE so that the mulfunctional PE would be recovered
620  * again.
621  */
622 static int pseries_eeh_configure_bridge(struct eeh_pe *pe)
623 {
624 	int config_addr;
625 	int ret;
626 
627 	/* Figure out the PE address */
628 	config_addr = pe->config_addr;
629 	if (pe->addr)
630 		config_addr = pe->addr;
631 
632 	/* Use new configure-pe function, if supported */
633 	if (ibm_configure_pe != RTAS_UNKNOWN_SERVICE) {
634 		ret = rtas_call(ibm_configure_pe, 3, 1, NULL,
635 				config_addr, BUID_HI(pe->phb->buid),
636 				BUID_LO(pe->phb->buid));
637 	} else if (ibm_configure_bridge != RTAS_UNKNOWN_SERVICE) {
638 		ret = rtas_call(ibm_configure_bridge, 3, 1, NULL,
639 				config_addr, BUID_HI(pe->phb->buid),
640 				BUID_LO(pe->phb->buid));
641 	} else {
642 		return -EFAULT;
643 	}
644 
645 	if (ret)
646 		pr_warn("%s: Unable to configure bridge PHB#%d-PE#%x (%d)\n",
647 			__func__, pe->phb->global_number, pe->addr, ret);
648 
649 	return ret;
650 }
651 
652 /**
653  * pseries_eeh_read_config - Read PCI config space
654  * @pdn: PCI device node
655  * @where: PCI address
656  * @size: size to read
657  * @val: return value
658  *
659  * Read config space from the speicifed device
660  */
661 static int pseries_eeh_read_config(struct pci_dn *pdn, int where, int size, u32 *val)
662 {
663 	return rtas_read_config(pdn, where, size, val);
664 }
665 
666 /**
667  * pseries_eeh_write_config - Write PCI config space
668  * @pdn: PCI device node
669  * @where: PCI address
670  * @size: size to write
671  * @val: value to be written
672  *
673  * Write config space to the specified device
674  */
675 static int pseries_eeh_write_config(struct pci_dn *pdn, int where, int size, u32 val)
676 {
677 	return rtas_write_config(pdn, where, size, val);
678 }
679 
680 static struct eeh_ops pseries_eeh_ops = {
681 	.name			= "pseries",
682 	.init			= pseries_eeh_init,
683 	.probe			= pseries_eeh_probe,
684 	.set_option		= pseries_eeh_set_option,
685 	.get_pe_addr		= pseries_eeh_get_pe_addr,
686 	.get_state		= pseries_eeh_get_state,
687 	.reset			= pseries_eeh_reset,
688 	.wait_state		= pseries_eeh_wait_state,
689 	.get_log		= pseries_eeh_get_log,
690 	.configure_bridge       = pseries_eeh_configure_bridge,
691 	.err_inject		= NULL,
692 	.read_config		= pseries_eeh_read_config,
693 	.write_config		= pseries_eeh_write_config,
694 	.next_error		= NULL,
695 	.restore_config		= NULL
696 };
697 
698 /**
699  * eeh_pseries_init - Register platform dependent EEH operations
700  *
701  * EEH initialization on pseries platform. This function should be
702  * called before any EEH related functions.
703  */
704 static int __init eeh_pseries_init(void)
705 {
706 	int ret;
707 
708 	ret = eeh_ops_register(&pseries_eeh_ops);
709 	if (!ret)
710 		pr_info("EEH: pSeries platform initialized\n");
711 	else
712 		pr_info("EEH: pSeries platform initialization failure (%d)\n",
713 			ret);
714 
715 	return ret;
716 }
717 machine_early_initcall(pseries, eeh_pseries_init);
718