1 /*
2  * The file intends to implement the platform dependent EEH operations on
3  * powernv platform. Actually, the powernv was created in order to fully
4  * hypervisor support.
5  *
6  * Copyright Benjamin Herrenschmidt & Gavin Shan, IBM Corporation 2013.
7  *
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
11  * (at your option) any later version.
12  */
13 
14 #include <linux/atomic.h>
15 #include <linux/debugfs.h>
16 #include <linux/delay.h>
17 #include <linux/export.h>
18 #include <linux/init.h>
19 #include <linux/list.h>
20 #include <linux/msi.h>
21 #include <linux/of.h>
22 #include <linux/pci.h>
23 #include <linux/proc_fs.h>
24 #include <linux/rbtree.h>
25 #include <linux/sched.h>
26 #include <linux/seq_file.h>
27 #include <linux/spinlock.h>
28 
29 #include <asm/eeh.h>
30 #include <asm/eeh_event.h>
31 #include <asm/firmware.h>
32 #include <asm/io.h>
33 #include <asm/iommu.h>
34 #include <asm/machdep.h>
35 #include <asm/msi_bitmap.h>
36 #include <asm/opal.h>
37 #include <asm/ppc-pci.h>
38 
39 #include "powernv.h"
40 #include "pci.h"
41 
42 static bool pnv_eeh_nb_init = false;
43 
44 /**
45  * pnv_eeh_init - EEH platform dependent initialization
46  *
47  * EEH platform dependent initialization on powernv
48  */
49 static int pnv_eeh_init(void)
50 {
51 	struct pci_controller *hose;
52 	struct pnv_phb *phb;
53 
54 	/* We require OPALv3 */
55 	if (!firmware_has_feature(FW_FEATURE_OPALv3)) {
56 		pr_warn("%s: OPALv3 is required !\n",
57 			__func__);
58 		return -EINVAL;
59 	}
60 
61 	/* Set probe mode */
62 	eeh_add_flag(EEH_PROBE_MODE_DEV);
63 
64 	/*
65 	 * P7IOC blocks PCI config access to frozen PE, but PHB3
66 	 * doesn't do that. So we have to selectively enable I/O
67 	 * prior to collecting error log.
68 	 */
69 	list_for_each_entry(hose, &hose_list, list_node) {
70 		phb = hose->private_data;
71 
72 		if (phb->model == PNV_PHB_MODEL_P7IOC)
73 			eeh_add_flag(EEH_ENABLE_IO_FOR_LOG);
74 
75 		/*
76 		 * PE#0 should be regarded as valid by EEH core
77 		 * if it's not the reserved one. Currently, we
78 		 * have the reserved PE#0 and PE#127 for PHB3
79 		 * and P7IOC separately. So we should regard
80 		 * PE#0 as valid for P7IOC.
81 		 */
82 		if (phb->ioda.reserved_pe != 0)
83 			eeh_add_flag(EEH_VALID_PE_ZERO);
84 
85 		break;
86 	}
87 
88 	return 0;
89 }
90 
91 static int pnv_eeh_event(struct notifier_block *nb,
92 			 unsigned long events, void *change)
93 {
94 	uint64_t changed_evts = (uint64_t)change;
95 
96 	/*
97 	 * We simply send special EEH event if EEH has
98 	 * been enabled, or clear pending events in
99 	 * case that we enable EEH soon
100 	 */
101 	if (!(changed_evts & OPAL_EVENT_PCI_ERROR) ||
102 	    !(events & OPAL_EVENT_PCI_ERROR))
103 		return 0;
104 
105 	if (eeh_enabled())
106 		eeh_send_failure_event(NULL);
107 	else
108 		opal_notifier_update_evt(OPAL_EVENT_PCI_ERROR, 0x0ul);
109 
110 	return 0;
111 }
112 
113 static struct notifier_block pnv_eeh_nb = {
114 	.notifier_call	= pnv_eeh_event,
115 	.next		= NULL,
116 	.priority	= 0
117 };
118 
119 #ifdef CONFIG_DEBUG_FS
120 static ssize_t pnv_eeh_ei_write(struct file *filp,
121 				const char __user *user_buf,
122 				size_t count, loff_t *ppos)
123 {
124 	struct pci_controller *hose = filp->private_data;
125 	struct eeh_dev *edev;
126 	struct eeh_pe *pe;
127 	int pe_no, type, func;
128 	unsigned long addr, mask;
129 	char buf[50];
130 	int ret;
131 
132 	if (!eeh_ops || !eeh_ops->err_inject)
133 		return -ENXIO;
134 
135 	/* Copy over argument buffer */
136 	ret = simple_write_to_buffer(buf, sizeof(buf), ppos, user_buf, count);
137 	if (!ret)
138 		return -EFAULT;
139 
140 	/* Retrieve parameters */
141 	ret = sscanf(buf, "%x:%x:%x:%lx:%lx",
142 		     &pe_no, &type, &func, &addr, &mask);
143 	if (ret != 5)
144 		return -EINVAL;
145 
146 	/* Retrieve PE */
147 	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
148 	if (!edev)
149 		return -ENOMEM;
150 	edev->phb = hose;
151 	edev->pe_config_addr = pe_no;
152 	pe = eeh_pe_get(edev);
153 	kfree(edev);
154 	if (!pe)
155 		return -ENODEV;
156 
157 	/* Do error injection */
158 	ret = eeh_ops->err_inject(pe, type, func, addr, mask);
159 	return ret < 0 ? ret : count;
160 }
161 
162 static const struct file_operations pnv_eeh_ei_fops = {
163 	.open	= simple_open,
164 	.llseek	= no_llseek,
165 	.write	= pnv_eeh_ei_write,
166 };
167 
168 static int pnv_eeh_dbgfs_set(void *data, int offset, u64 val)
169 {
170 	struct pci_controller *hose = data;
171 	struct pnv_phb *phb = hose->private_data;
172 
173 	out_be64(phb->regs + offset, val);
174 	return 0;
175 }
176 
177 static int pnv_eeh_dbgfs_get(void *data, int offset, u64 *val)
178 {
179 	struct pci_controller *hose = data;
180 	struct pnv_phb *phb = hose->private_data;
181 
182 	*val = in_be64(phb->regs + offset);
183 	return 0;
184 }
185 
186 static int pnv_eeh_outb_dbgfs_set(void *data, u64 val)
187 {
188 	return pnv_eeh_dbgfs_set(data, 0xD10, val);
189 }
190 
191 static int pnv_eeh_outb_dbgfs_get(void *data, u64 *val)
192 {
193 	return pnv_eeh_dbgfs_get(data, 0xD10, val);
194 }
195 
196 static int pnv_eeh_inbA_dbgfs_set(void *data, u64 val)
197 {
198 	return pnv_eeh_dbgfs_set(data, 0xD90, val);
199 }
200 
201 static int pnv_eeh_inbA_dbgfs_get(void *data, u64 *val)
202 {
203 	return pnv_eeh_dbgfs_get(data, 0xD90, val);
204 }
205 
206 static int pnv_eeh_inbB_dbgfs_set(void *data, u64 val)
207 {
208 	return pnv_eeh_dbgfs_set(data, 0xE10, val);
209 }
210 
211 static int pnv_eeh_inbB_dbgfs_get(void *data, u64 *val)
212 {
213 	return pnv_eeh_dbgfs_get(data, 0xE10, val);
214 }
215 
216 DEFINE_SIMPLE_ATTRIBUTE(pnv_eeh_outb_dbgfs_ops, pnv_eeh_outb_dbgfs_get,
217 			pnv_eeh_outb_dbgfs_set, "0x%llx\n");
218 DEFINE_SIMPLE_ATTRIBUTE(pnv_eeh_inbA_dbgfs_ops, pnv_eeh_inbA_dbgfs_get,
219 			pnv_eeh_inbA_dbgfs_set, "0x%llx\n");
220 DEFINE_SIMPLE_ATTRIBUTE(pnv_eeh_inbB_dbgfs_ops, pnv_eeh_inbB_dbgfs_get,
221 			pnv_eeh_inbB_dbgfs_set, "0x%llx\n");
222 #endif /* CONFIG_DEBUG_FS */
223 
224 /**
225  * pnv_eeh_post_init - EEH platform dependent post initialization
226  *
227  * EEH platform dependent post initialization on powernv. When
228  * the function is called, the EEH PEs and devices should have
229  * been built. If the I/O cache staff has been built, EEH is
230  * ready to supply service.
231  */
232 static int pnv_eeh_post_init(void)
233 {
234 	struct pci_controller *hose;
235 	struct pnv_phb *phb;
236 	int ret = 0;
237 
238 	/* Register OPAL event notifier */
239 	if (!pnv_eeh_nb_init) {
240 		ret = opal_notifier_register(&pnv_eeh_nb);
241 		if (ret) {
242 			pr_warn("%s: Can't register OPAL event notifier (%d)\n",
243 				__func__, ret);
244 			return ret;
245 		}
246 
247 		pnv_eeh_nb_init = true;
248 	}
249 
250 	list_for_each_entry(hose, &hose_list, list_node) {
251 		phb = hose->private_data;
252 
253 		/*
254 		 * If EEH is enabled, we're going to rely on that.
255 		 * Otherwise, we restore to conventional mechanism
256 		 * to clear frozen PE during PCI config access.
257 		 */
258 		if (eeh_enabled())
259 			phb->flags |= PNV_PHB_FLAG_EEH;
260 		else
261 			phb->flags &= ~PNV_PHB_FLAG_EEH;
262 
263 		/* Create debugfs entries */
264 #ifdef CONFIG_DEBUG_FS
265 		if (phb->has_dbgfs || !phb->dbgfs)
266 			continue;
267 
268 		phb->has_dbgfs = 1;
269 		debugfs_create_file("err_injct", 0200,
270 				    phb->dbgfs, hose,
271 				    &pnv_eeh_ei_fops);
272 
273 		debugfs_create_file("err_injct_outbound", 0600,
274 				    phb->dbgfs, hose,
275 				    &pnv_eeh_outb_dbgfs_ops);
276 		debugfs_create_file("err_injct_inboundA", 0600,
277 				    phb->dbgfs, hose,
278 				    &pnv_eeh_inbA_dbgfs_ops);
279 		debugfs_create_file("err_injct_inboundB", 0600,
280 				    phb->dbgfs, hose,
281 				    &pnv_eeh_inbB_dbgfs_ops);
282 #endif /* CONFIG_DEBUG_FS */
283 	}
284 
285 
286 	return ret;
287 }
288 
289 static int pnv_eeh_cap_start(struct pci_dn *pdn)
290 {
291 	u32 status;
292 
293 	if (!pdn)
294 		return 0;
295 
296 	pnv_pci_cfg_read(pdn, PCI_STATUS, 2, &status);
297 	if (!(status & PCI_STATUS_CAP_LIST))
298 		return 0;
299 
300 	return PCI_CAPABILITY_LIST;
301 }
302 
303 static int pnv_eeh_find_cap(struct pci_dn *pdn, int cap)
304 {
305 	int pos = pnv_eeh_cap_start(pdn);
306 	int cnt = 48;   /* Maximal number of capabilities */
307 	u32 id;
308 
309 	if (!pos)
310 		return 0;
311 
312 	while (cnt--) {
313 		pnv_pci_cfg_read(pdn, pos, 1, &pos);
314 		if (pos < 0x40)
315 			break;
316 
317 		pos &= ~3;
318 		pnv_pci_cfg_read(pdn, pos + PCI_CAP_LIST_ID, 1, &id);
319 		if (id == 0xff)
320 			break;
321 
322 		/* Found */
323 		if (id == cap)
324 			return pos;
325 
326 		/* Next one */
327 		pos += PCI_CAP_LIST_NEXT;
328 	}
329 
330 	return 0;
331 }
332 
333 static int pnv_eeh_find_ecap(struct pci_dn *pdn, int cap)
334 {
335 	struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
336 	u32 header;
337 	int pos = 256, ttl = (4096 - 256) / 8;
338 
339 	if (!edev || !edev->pcie_cap)
340 		return 0;
341 	if (pnv_pci_cfg_read(pdn, pos, 4, &header) != PCIBIOS_SUCCESSFUL)
342 		return 0;
343 	else if (!header)
344 		return 0;
345 
346 	while (ttl-- > 0) {
347 		if (PCI_EXT_CAP_ID(header) == cap && pos)
348 			return pos;
349 
350 		pos = PCI_EXT_CAP_NEXT(header);
351 		if (pos < 256)
352 			break;
353 
354 		if (pnv_pci_cfg_read(pdn, pos, 4, &header) != PCIBIOS_SUCCESSFUL)
355 			break;
356 	}
357 
358 	return 0;
359 }
360 
361 /**
362  * pnv_eeh_probe - Do probe on PCI device
363  * @pdn: PCI device node
364  * @data: unused
365  *
366  * When EEH module is installed during system boot, all PCI devices
367  * are checked one by one to see if it supports EEH. The function
368  * is introduced for the purpose. By default, EEH has been enabled
369  * on all PCI devices. That's to say, we only need do necessary
370  * initialization on the corresponding eeh device and create PE
371  * accordingly.
372  *
373  * It's notable that's unsafe to retrieve the EEH device through
374  * the corresponding PCI device. During the PCI device hotplug, which
375  * was possiblly triggered by EEH core, the binding between EEH device
376  * and the PCI device isn't built yet.
377  */
378 static void *pnv_eeh_probe(struct pci_dn *pdn, void *data)
379 {
380 	struct pci_controller *hose = pdn->phb;
381 	struct pnv_phb *phb = hose->private_data;
382 	struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
383 	uint32_t pcie_flags;
384 	int ret;
385 
386 	/*
387 	 * When probing the root bridge, which doesn't have any
388 	 * subordinate PCI devices. We don't have OF node for
389 	 * the root bridge. So it's not reasonable to continue
390 	 * the probing.
391 	 */
392 	if (!edev || edev->pe)
393 		return NULL;
394 
395 	/* Skip for PCI-ISA bridge */
396 	if ((pdn->class_code >> 8) == PCI_CLASS_BRIDGE_ISA)
397 		return NULL;
398 
399 	/* Initialize eeh device */
400 	edev->class_code = pdn->class_code;
401 	edev->mode	&= 0xFFFFFF00;
402 	edev->pcix_cap = pnv_eeh_find_cap(pdn, PCI_CAP_ID_PCIX);
403 	edev->pcie_cap = pnv_eeh_find_cap(pdn, PCI_CAP_ID_EXP);
404 	edev->aer_cap  = pnv_eeh_find_ecap(pdn, PCI_EXT_CAP_ID_ERR);
405 	if ((edev->class_code >> 8) == PCI_CLASS_BRIDGE_PCI) {
406 		edev->mode |= EEH_DEV_BRIDGE;
407 		if (edev->pcie_cap) {
408 			pnv_pci_cfg_read(pdn, edev->pcie_cap + PCI_EXP_FLAGS,
409 					 2, &pcie_flags);
410 			pcie_flags = (pcie_flags & PCI_EXP_FLAGS_TYPE) >> 4;
411 			if (pcie_flags == PCI_EXP_TYPE_ROOT_PORT)
412 				edev->mode |= EEH_DEV_ROOT_PORT;
413 			else if (pcie_flags == PCI_EXP_TYPE_DOWNSTREAM)
414 				edev->mode |= EEH_DEV_DS_PORT;
415 		}
416 	}
417 
418 	edev->config_addr    = (pdn->busno << 8) | (pdn->devfn);
419 	edev->pe_config_addr = phb->ioda.pe_rmap[edev->config_addr];
420 
421 	/* Create PE */
422 	ret = eeh_add_to_parent_pe(edev);
423 	if (ret) {
424 		pr_warn("%s: Can't add PCI dev %04x:%02x:%02x.%01x to parent PE (%d)\n",
425 			__func__, hose->global_number, pdn->busno,
426 			PCI_SLOT(pdn->devfn), PCI_FUNC(pdn->devfn), ret);
427 		return NULL;
428 	}
429 
430 	/*
431 	 * If the PE contains any one of following adapters, the
432 	 * PCI config space can't be accessed when dumping EEH log.
433 	 * Otherwise, we will run into fenced PHB caused by shortage
434 	 * of outbound credits in the adapter. The PCI config access
435 	 * should be blocked until PE reset. MMIO access is dropped
436 	 * by hardware certainly. In order to drop PCI config requests,
437 	 * one more flag (EEH_PE_CFG_RESTRICTED) is introduced, which
438 	 * will be checked in the backend for PE state retrival. If
439 	 * the PE becomes frozen for the first time and the flag has
440 	 * been set for the PE, we will set EEH_PE_CFG_BLOCKED for
441 	 * that PE to block its config space.
442 	 *
443 	 * Broadcom Austin 4-ports NICs (14e4:1657)
444 	 * Broadcom Shiner 2-ports 10G NICs (14e4:168e)
445 	 */
446 	if ((pdn->vendor_id == PCI_VENDOR_ID_BROADCOM &&
447 	     pdn->device_id == 0x1657) ||
448 	    (pdn->vendor_id == PCI_VENDOR_ID_BROADCOM &&
449 	     pdn->device_id == 0x168e))
450 		edev->pe->state |= EEH_PE_CFG_RESTRICTED;
451 
452 	/*
453 	 * Cache the PE primary bus, which can't be fetched when
454 	 * full hotplug is in progress. In that case, all child
455 	 * PCI devices of the PE are expected to be removed prior
456 	 * to PE reset.
457 	 */
458 	if (!edev->pe->bus)
459 		edev->pe->bus = pci_find_bus(hose->global_number,
460 					     pdn->busno);
461 
462 	/*
463 	 * Enable EEH explicitly so that we will do EEH check
464 	 * while accessing I/O stuff
465 	 */
466 	eeh_add_flag(EEH_ENABLED);
467 
468 	/* Save memory bars */
469 	eeh_save_bars(edev);
470 
471 	return NULL;
472 }
473 
474 /**
475  * pnv_eeh_set_option - Initialize EEH or MMIO/DMA reenable
476  * @pe: EEH PE
477  * @option: operation to be issued
478  *
479  * The function is used to control the EEH functionality globally.
480  * Currently, following options are support according to PAPR:
481  * Enable EEH, Disable EEH, Enable MMIO and Enable DMA
482  */
483 static int pnv_eeh_set_option(struct eeh_pe *pe, int option)
484 {
485 	struct pci_controller *hose = pe->phb;
486 	struct pnv_phb *phb = hose->private_data;
487 	bool freeze_pe = false;
488 	int opt, ret = 0;
489 	s64 rc;
490 
491 	/* Sanity check on option */
492 	switch (option) {
493 	case EEH_OPT_DISABLE:
494 		return -EPERM;
495 	case EEH_OPT_ENABLE:
496 		return 0;
497 	case EEH_OPT_THAW_MMIO:
498 		opt = OPAL_EEH_ACTION_CLEAR_FREEZE_MMIO;
499 		break;
500 	case EEH_OPT_THAW_DMA:
501 		opt = OPAL_EEH_ACTION_CLEAR_FREEZE_DMA;
502 		break;
503 	case EEH_OPT_FREEZE_PE:
504 		freeze_pe = true;
505 		opt = OPAL_EEH_ACTION_SET_FREEZE_ALL;
506 		break;
507 	default:
508 		pr_warn("%s: Invalid option %d\n", __func__, option);
509 		return -EINVAL;
510 	}
511 
512 	/* If PHB supports compound PE, to handle it */
513 	if (freeze_pe) {
514 		if (phb->freeze_pe) {
515 			phb->freeze_pe(phb, pe->addr);
516 		} else {
517 			rc = opal_pci_eeh_freeze_set(phb->opal_id,
518 						     pe->addr, opt);
519 			if (rc != OPAL_SUCCESS) {
520 				pr_warn("%s: Failure %lld freezing "
521 					"PHB#%x-PE#%x\n",
522 					__func__, rc,
523 					phb->hose->global_number, pe->addr);
524 				ret = -EIO;
525 			}
526 		}
527 	} else {
528 		if (phb->unfreeze_pe) {
529 			ret = phb->unfreeze_pe(phb, pe->addr, opt);
530 		} else {
531 			rc = opal_pci_eeh_freeze_clear(phb->opal_id,
532 						       pe->addr, opt);
533 			if (rc != OPAL_SUCCESS) {
534 				pr_warn("%s: Failure %lld enable %d "
535 					"for PHB#%x-PE#%x\n",
536 					__func__, rc, option,
537 					phb->hose->global_number, pe->addr);
538 				ret = -EIO;
539 			}
540 		}
541 	}
542 
543 	return ret;
544 }
545 
546 /**
547  * pnv_eeh_get_pe_addr - Retrieve PE address
548  * @pe: EEH PE
549  *
550  * Retrieve the PE address according to the given tranditional
551  * PCI BDF (Bus/Device/Function) address.
552  */
553 static int pnv_eeh_get_pe_addr(struct eeh_pe *pe)
554 {
555 	return pe->addr;
556 }
557 
558 static void pnv_eeh_get_phb_diag(struct eeh_pe *pe)
559 {
560 	struct pnv_phb *phb = pe->phb->private_data;
561 	s64 rc;
562 
563 	rc = opal_pci_get_phb_diag_data2(phb->opal_id, pe->data,
564 					 PNV_PCI_DIAG_BUF_SIZE);
565 	if (rc != OPAL_SUCCESS)
566 		pr_warn("%s: Failure %lld getting PHB#%x diag-data\n",
567 			__func__, rc, pe->phb->global_number);
568 }
569 
570 static int pnv_eeh_get_phb_state(struct eeh_pe *pe)
571 {
572 	struct pnv_phb *phb = pe->phb->private_data;
573 	u8 fstate;
574 	__be16 pcierr;
575 	s64 rc;
576 	int result = 0;
577 
578 	rc = opal_pci_eeh_freeze_status(phb->opal_id,
579 					pe->addr,
580 					&fstate,
581 					&pcierr,
582 					NULL);
583 	if (rc != OPAL_SUCCESS) {
584 		pr_warn("%s: Failure %lld getting PHB#%x state\n",
585 			__func__, rc, phb->hose->global_number);
586 		return EEH_STATE_NOT_SUPPORT;
587 	}
588 
589 	/*
590 	 * Check PHB state. If the PHB is frozen for the
591 	 * first time, to dump the PHB diag-data.
592 	 */
593 	if (be16_to_cpu(pcierr) != OPAL_EEH_PHB_ERROR) {
594 		result = (EEH_STATE_MMIO_ACTIVE  |
595 			  EEH_STATE_DMA_ACTIVE   |
596 			  EEH_STATE_MMIO_ENABLED |
597 			  EEH_STATE_DMA_ENABLED);
598 	} else if (!(pe->state & EEH_PE_ISOLATED)) {
599 		eeh_pe_state_mark(pe, EEH_PE_ISOLATED);
600 		pnv_eeh_get_phb_diag(pe);
601 
602 		if (eeh_has_flag(EEH_EARLY_DUMP_LOG))
603 			pnv_pci_dump_phb_diag_data(pe->phb, pe->data);
604 	}
605 
606 	return result;
607 }
608 
609 static int pnv_eeh_get_pe_state(struct eeh_pe *pe)
610 {
611 	struct pnv_phb *phb = pe->phb->private_data;
612 	u8 fstate;
613 	__be16 pcierr;
614 	s64 rc;
615 	int result;
616 
617 	/*
618 	 * We don't clobber hardware frozen state until PE
619 	 * reset is completed. In order to keep EEH core
620 	 * moving forward, we have to return operational
621 	 * state during PE reset.
622 	 */
623 	if (pe->state & EEH_PE_RESET) {
624 		result = (EEH_STATE_MMIO_ACTIVE  |
625 			  EEH_STATE_DMA_ACTIVE   |
626 			  EEH_STATE_MMIO_ENABLED |
627 			  EEH_STATE_DMA_ENABLED);
628 		return result;
629 	}
630 
631 	/*
632 	 * Fetch PE state from hardware. If the PHB
633 	 * supports compound PE, let it handle that.
634 	 */
635 	if (phb->get_pe_state) {
636 		fstate = phb->get_pe_state(phb, pe->addr);
637 	} else {
638 		rc = opal_pci_eeh_freeze_status(phb->opal_id,
639 						pe->addr,
640 						&fstate,
641 						&pcierr,
642 						NULL);
643 		if (rc != OPAL_SUCCESS) {
644 			pr_warn("%s: Failure %lld getting PHB#%x-PE%x state\n",
645 				__func__, rc, phb->hose->global_number,
646 				pe->addr);
647 			return EEH_STATE_NOT_SUPPORT;
648 		}
649 	}
650 
651 	/* Figure out state */
652 	switch (fstate) {
653 	case OPAL_EEH_STOPPED_NOT_FROZEN:
654 		result = (EEH_STATE_MMIO_ACTIVE  |
655 			  EEH_STATE_DMA_ACTIVE   |
656 			  EEH_STATE_MMIO_ENABLED |
657 			  EEH_STATE_DMA_ENABLED);
658 		break;
659 	case OPAL_EEH_STOPPED_MMIO_FREEZE:
660 		result = (EEH_STATE_DMA_ACTIVE |
661 			  EEH_STATE_DMA_ENABLED);
662 		break;
663 	case OPAL_EEH_STOPPED_DMA_FREEZE:
664 		result = (EEH_STATE_MMIO_ACTIVE |
665 			  EEH_STATE_MMIO_ENABLED);
666 		break;
667 	case OPAL_EEH_STOPPED_MMIO_DMA_FREEZE:
668 		result = 0;
669 		break;
670 	case OPAL_EEH_STOPPED_RESET:
671 		result = EEH_STATE_RESET_ACTIVE;
672 		break;
673 	case OPAL_EEH_STOPPED_TEMP_UNAVAIL:
674 		result = EEH_STATE_UNAVAILABLE;
675 		break;
676 	case OPAL_EEH_STOPPED_PERM_UNAVAIL:
677 		result = EEH_STATE_NOT_SUPPORT;
678 		break;
679 	default:
680 		result = EEH_STATE_NOT_SUPPORT;
681 		pr_warn("%s: Invalid PHB#%x-PE#%x state %x\n",
682 			__func__, phb->hose->global_number,
683 			pe->addr, fstate);
684 	}
685 
686 	/*
687 	 * If PHB supports compound PE, to freeze all
688 	 * slave PEs for consistency.
689 	 *
690 	 * If the PE is switching to frozen state for the
691 	 * first time, to dump the PHB diag-data.
692 	 */
693 	if (!(result & EEH_STATE_NOT_SUPPORT) &&
694 	    !(result & EEH_STATE_UNAVAILABLE) &&
695 	    !(result & EEH_STATE_MMIO_ACTIVE) &&
696 	    !(result & EEH_STATE_DMA_ACTIVE)  &&
697 	    !(pe->state & EEH_PE_ISOLATED)) {
698 		if (phb->freeze_pe)
699 			phb->freeze_pe(phb, pe->addr);
700 
701 		eeh_pe_state_mark(pe, EEH_PE_ISOLATED);
702 		pnv_eeh_get_phb_diag(pe);
703 
704 		if (eeh_has_flag(EEH_EARLY_DUMP_LOG))
705 			pnv_pci_dump_phb_diag_data(pe->phb, pe->data);
706 	}
707 
708 	return result;
709 }
710 
711 /**
712  * pnv_eeh_get_state - Retrieve PE state
713  * @pe: EEH PE
714  * @delay: delay while PE state is temporarily unavailable
715  *
716  * Retrieve the state of the specified PE. For IODA-compitable
717  * platform, it should be retrieved from IODA table. Therefore,
718  * we prefer passing down to hardware implementation to handle
719  * it.
720  */
721 static int pnv_eeh_get_state(struct eeh_pe *pe, int *delay)
722 {
723 	int ret;
724 
725 	if (pe->type & EEH_PE_PHB)
726 		ret = pnv_eeh_get_phb_state(pe);
727 	else
728 		ret = pnv_eeh_get_pe_state(pe);
729 
730 	if (!delay)
731 		return ret;
732 
733 	/*
734 	 * If the PE state is temporarily unavailable,
735 	 * to inform the EEH core delay for default
736 	 * period (1 second)
737 	 */
738 	*delay = 0;
739 	if (ret & EEH_STATE_UNAVAILABLE)
740 		*delay = 1000;
741 
742 	return ret;
743 }
744 
745 static s64 pnv_eeh_phb_poll(struct pnv_phb *phb)
746 {
747 	s64 rc = OPAL_HARDWARE;
748 
749 	while (1) {
750 		rc = opal_pci_poll(phb->opal_id);
751 		if (rc <= 0)
752 			break;
753 
754 		if (system_state < SYSTEM_RUNNING)
755 			udelay(1000 * rc);
756 		else
757 			msleep(rc);
758 	}
759 
760 	return rc;
761 }
762 
763 int pnv_eeh_phb_reset(struct pci_controller *hose, int option)
764 {
765 	struct pnv_phb *phb = hose->private_data;
766 	s64 rc = OPAL_HARDWARE;
767 
768 	pr_debug("%s: Reset PHB#%x, option=%d\n",
769 		 __func__, hose->global_number, option);
770 
771 	/* Issue PHB complete reset request */
772 	if (option == EEH_RESET_FUNDAMENTAL ||
773 	    option == EEH_RESET_HOT)
774 		rc = opal_pci_reset(phb->opal_id,
775 				    OPAL_RESET_PHB_COMPLETE,
776 				    OPAL_ASSERT_RESET);
777 	else if (option == EEH_RESET_DEACTIVATE)
778 		rc = opal_pci_reset(phb->opal_id,
779 				    OPAL_RESET_PHB_COMPLETE,
780 				    OPAL_DEASSERT_RESET);
781 	if (rc < 0)
782 		goto out;
783 
784 	/*
785 	 * Poll state of the PHB until the request is done
786 	 * successfully. The PHB reset is usually PHB complete
787 	 * reset followed by hot reset on root bus. So we also
788 	 * need the PCI bus settlement delay.
789 	 */
790 	rc = pnv_eeh_phb_poll(phb);
791 	if (option == EEH_RESET_DEACTIVATE) {
792 		if (system_state < SYSTEM_RUNNING)
793 			udelay(1000 * EEH_PE_RST_SETTLE_TIME);
794 		else
795 			msleep(EEH_PE_RST_SETTLE_TIME);
796 	}
797 out:
798 	if (rc != OPAL_SUCCESS)
799 		return -EIO;
800 
801 	return 0;
802 }
803 
804 static int pnv_eeh_root_reset(struct pci_controller *hose, int option)
805 {
806 	struct pnv_phb *phb = hose->private_data;
807 	s64 rc = OPAL_HARDWARE;
808 
809 	pr_debug("%s: Reset PHB#%x, option=%d\n",
810 		 __func__, hose->global_number, option);
811 
812 	/*
813 	 * During the reset deassert time, we needn't care
814 	 * the reset scope because the firmware does nothing
815 	 * for fundamental or hot reset during deassert phase.
816 	 */
817 	if (option == EEH_RESET_FUNDAMENTAL)
818 		rc = opal_pci_reset(phb->opal_id,
819 				    OPAL_RESET_PCI_FUNDAMENTAL,
820 				    OPAL_ASSERT_RESET);
821 	else if (option == EEH_RESET_HOT)
822 		rc = opal_pci_reset(phb->opal_id,
823 				    OPAL_RESET_PCI_HOT,
824 				    OPAL_ASSERT_RESET);
825 	else if (option == EEH_RESET_DEACTIVATE)
826 		rc = opal_pci_reset(phb->opal_id,
827 				    OPAL_RESET_PCI_HOT,
828 				    OPAL_DEASSERT_RESET);
829 	if (rc < 0)
830 		goto out;
831 
832 	/* Poll state of the PHB until the request is done */
833 	rc = pnv_eeh_phb_poll(phb);
834 	if (option == EEH_RESET_DEACTIVATE)
835 		msleep(EEH_PE_RST_SETTLE_TIME);
836 out:
837 	if (rc != OPAL_SUCCESS)
838 		return -EIO;
839 
840 	return 0;
841 }
842 
843 static int pnv_eeh_bridge_reset(struct pci_dev *dev, int option)
844 {
845 	struct device_node *dn = pci_device_to_OF_node(dev);
846 	struct eeh_dev *edev = of_node_to_eeh_dev(dn);
847 	int aer = edev ? edev->aer_cap : 0;
848 	u32 ctrl;
849 
850 	pr_debug("%s: Reset PCI bus %04x:%02x with option %d\n",
851 		 __func__, pci_domain_nr(dev->bus),
852 		 dev->bus->number, option);
853 
854 	switch (option) {
855 	case EEH_RESET_FUNDAMENTAL:
856 	case EEH_RESET_HOT:
857 		/* Don't report linkDown event */
858 		if (aer) {
859 			eeh_ops->read_config(dn, aer + PCI_ERR_UNCOR_MASK,
860 					     4, &ctrl);
861 			ctrl |= PCI_ERR_UNC_SURPDN;
862 			eeh_ops->write_config(dn, aer + PCI_ERR_UNCOR_MASK,
863 					      4, ctrl);
864 		}
865 
866 		eeh_ops->read_config(dn, PCI_BRIDGE_CONTROL, 2, &ctrl);
867 		ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
868 		eeh_ops->write_config(dn, PCI_BRIDGE_CONTROL, 2, ctrl);
869 
870 		msleep(EEH_PE_RST_HOLD_TIME);
871 		break;
872 	case EEH_RESET_DEACTIVATE:
873 		eeh_ops->read_config(dn, PCI_BRIDGE_CONTROL, 2, &ctrl);
874 		ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
875 		eeh_ops->write_config(dn, PCI_BRIDGE_CONTROL, 2, ctrl);
876 
877 		msleep(EEH_PE_RST_SETTLE_TIME);
878 
879 		/* Continue reporting linkDown event */
880 		if (aer) {
881 			eeh_ops->read_config(dn, aer + PCI_ERR_UNCOR_MASK,
882 					     4, &ctrl);
883 			ctrl &= ~PCI_ERR_UNC_SURPDN;
884 			eeh_ops->write_config(dn, aer + PCI_ERR_UNCOR_MASK,
885 					      4, ctrl);
886 		}
887 
888 		break;
889 	}
890 
891 	return 0;
892 }
893 
894 void pnv_pci_reset_secondary_bus(struct pci_dev *dev)
895 {
896 	struct pci_controller *hose;
897 
898 	if (pci_is_root_bus(dev->bus)) {
899 		hose = pci_bus_to_host(dev->bus);
900 		pnv_eeh_root_reset(hose, EEH_RESET_HOT);
901 		pnv_eeh_root_reset(hose, EEH_RESET_DEACTIVATE);
902 	} else {
903 		pnv_eeh_bridge_reset(dev, EEH_RESET_HOT);
904 		pnv_eeh_bridge_reset(dev, EEH_RESET_DEACTIVATE);
905 	}
906 }
907 
908 /**
909  * pnv_eeh_reset - Reset the specified PE
910  * @pe: EEH PE
911  * @option: reset option
912  *
913  * Do reset on the indicated PE. For PCI bus sensitive PE,
914  * we need to reset the parent p2p bridge. The PHB has to
915  * be reinitialized if the p2p bridge is root bridge. For
916  * PCI device sensitive PE, we will try to reset the device
917  * through FLR. For now, we don't have OPAL APIs to do HARD
918  * reset yet, so all reset would be SOFT (HOT) reset.
919  */
920 static int pnv_eeh_reset(struct eeh_pe *pe, int option)
921 {
922 	struct pci_controller *hose = pe->phb;
923 	struct pci_bus *bus;
924 	int ret;
925 
926 	/*
927 	 * For PHB reset, we always have complete reset. For those PEs whose
928 	 * primary bus derived from root complex (root bus) or root port
929 	 * (usually bus#1), we apply hot or fundamental reset on the root port.
930 	 * For other PEs, we always have hot reset on the PE primary bus.
931 	 *
932 	 * Here, we have different design to pHyp, which always clear the
933 	 * frozen state during PE reset. However, the good idea here from
934 	 * benh is to keep frozen state before we get PE reset done completely
935 	 * (until BAR restore). With the frozen state, HW drops illegal IO
936 	 * or MMIO access, which can incur recrusive frozen PE during PE
937 	 * reset. The side effect is that EEH core has to clear the frozen
938 	 * state explicitly after BAR restore.
939 	 */
940 	if (pe->type & EEH_PE_PHB) {
941 		ret = pnv_eeh_phb_reset(hose, option);
942 	} else {
943 		struct pnv_phb *phb;
944 		s64 rc;
945 
946 		/*
947 		 * The frozen PE might be caused by PAPR error injection
948 		 * registers, which are expected to be cleared after hitting
949 		 * frozen PE as stated in the hardware spec. Unfortunately,
950 		 * that's not true on P7IOC. So we have to clear it manually
951 		 * to avoid recursive EEH errors during recovery.
952 		 */
953 		phb = hose->private_data;
954 		if (phb->model == PNV_PHB_MODEL_P7IOC &&
955 		    (option == EEH_RESET_HOT ||
956 		    option == EEH_RESET_FUNDAMENTAL)) {
957 			rc = opal_pci_reset(phb->opal_id,
958 					    OPAL_RESET_PHB_ERROR,
959 					    OPAL_ASSERT_RESET);
960 			if (rc != OPAL_SUCCESS) {
961 				pr_warn("%s: Failure %lld clearing "
962 					"error injection registers\n",
963 					__func__, rc);
964 				return -EIO;
965 			}
966 		}
967 
968 		bus = eeh_pe_bus_get(pe);
969 		if (pci_is_root_bus(bus) ||
970 			pci_is_root_bus(bus->parent))
971 			ret = pnv_eeh_root_reset(hose, option);
972 		else
973 			ret = pnv_eeh_bridge_reset(bus->self, option);
974 	}
975 
976 	return ret;
977 }
978 
979 /**
980  * pnv_eeh_wait_state - Wait for PE state
981  * @pe: EEH PE
982  * @max_wait: maximal period in microsecond
983  *
984  * Wait for the state of associated PE. It might take some time
985  * to retrieve the PE's state.
986  */
987 static int pnv_eeh_wait_state(struct eeh_pe *pe, int max_wait)
988 {
989 	int ret;
990 	int mwait;
991 
992 	while (1) {
993 		ret = pnv_eeh_get_state(pe, &mwait);
994 
995 		/*
996 		 * If the PE's state is temporarily unavailable,
997 		 * we have to wait for the specified time. Otherwise,
998 		 * the PE's state will be returned immediately.
999 		 */
1000 		if (ret != EEH_STATE_UNAVAILABLE)
1001 			return ret;
1002 
1003 		max_wait -= mwait;
1004 		if (max_wait <= 0) {
1005 			pr_warn("%s: Timeout getting PE#%x's state (%d)\n",
1006 				__func__, pe->addr, max_wait);
1007 			return EEH_STATE_NOT_SUPPORT;
1008 		}
1009 
1010 		msleep(mwait);
1011 	}
1012 
1013 	return EEH_STATE_NOT_SUPPORT;
1014 }
1015 
1016 /**
1017  * pnv_eeh_get_log - Retrieve error log
1018  * @pe: EEH PE
1019  * @severity: temporary or permanent error log
1020  * @drv_log: driver log to be combined with retrieved error log
1021  * @len: length of driver log
1022  *
1023  * Retrieve the temporary or permanent error from the PE.
1024  */
1025 static int pnv_eeh_get_log(struct eeh_pe *pe, int severity,
1026 			   char *drv_log, unsigned long len)
1027 {
1028 	if (!eeh_has_flag(EEH_EARLY_DUMP_LOG))
1029 		pnv_pci_dump_phb_diag_data(pe->phb, pe->data);
1030 
1031 	return 0;
1032 }
1033 
1034 /**
1035  * pnv_eeh_configure_bridge - Configure PCI bridges in the indicated PE
1036  * @pe: EEH PE
1037  *
1038  * The function will be called to reconfigure the bridges included
1039  * in the specified PE so that the mulfunctional PE would be recovered
1040  * again.
1041  */
1042 static int pnv_eeh_configure_bridge(struct eeh_pe *pe)
1043 {
1044 	return 0;
1045 }
1046 
1047 /**
1048  * pnv_pe_err_inject - Inject specified error to the indicated PE
1049  * @pe: the indicated PE
1050  * @type: error type
1051  * @func: specific error type
1052  * @addr: address
1053  * @mask: address mask
1054  *
1055  * The routine is called to inject specified error, which is
1056  * determined by @type and @func, to the indicated PE for
1057  * testing purpose.
1058  */
1059 static int pnv_eeh_err_inject(struct eeh_pe *pe, int type, int func,
1060 			      unsigned long addr, unsigned long mask)
1061 {
1062 	struct pci_controller *hose = pe->phb;
1063 	struct pnv_phb *phb = hose->private_data;
1064 	s64 rc;
1065 
1066 	/* Sanity check on error type */
1067 	if (type != OPAL_ERR_INJECT_TYPE_IOA_BUS_ERR &&
1068 	    type != OPAL_ERR_INJECT_TYPE_IOA_BUS_ERR64) {
1069 		pr_warn("%s: Invalid error type %d\n",
1070 			__func__, type);
1071 		return -ERANGE;
1072 	}
1073 
1074 	if (func < OPAL_ERR_INJECT_FUNC_IOA_LD_MEM_ADDR ||
1075 	    func > OPAL_ERR_INJECT_FUNC_IOA_DMA_WR_TARGET) {
1076 		pr_warn("%s: Invalid error function %d\n",
1077 			__func__, func);
1078 		return -ERANGE;
1079 	}
1080 
1081 	/* Firmware supports error injection ? */
1082 	if (!opal_check_token(OPAL_PCI_ERR_INJECT)) {
1083 		pr_warn("%s: Firmware doesn't support error injection\n",
1084 			__func__);
1085 		return -ENXIO;
1086 	}
1087 
1088 	/* Do error injection */
1089 	rc = opal_pci_err_inject(phb->opal_id, pe->addr,
1090 				 type, func, addr, mask);
1091 	if (rc != OPAL_SUCCESS) {
1092 		pr_warn("%s: Failure %lld injecting error "
1093 			"%d-%d to PHB#%x-PE#%x\n",
1094 			__func__, rc, type, func,
1095 			hose->global_number, pe->addr);
1096 		return -EIO;
1097 	}
1098 
1099 	return 0;
1100 }
1101 
1102 static inline bool pnv_eeh_cfg_blocked(struct device_node *dn)
1103 {
1104 	struct eeh_dev *edev = of_node_to_eeh_dev(dn);
1105 
1106 	if (!edev || !edev->pe)
1107 		return false;
1108 
1109 	if (edev->pe->state & EEH_PE_CFG_BLOCKED)
1110 		return true;
1111 
1112 	return false;
1113 }
1114 
1115 static int pnv_eeh_read_config(struct device_node *dn,
1116 			       int where, int size, u32 *val)
1117 {
1118 	struct pci_dn *pdn = PCI_DN(dn);
1119 
1120 	if (!pdn)
1121 		return PCIBIOS_DEVICE_NOT_FOUND;
1122 
1123 	if (pnv_eeh_cfg_blocked(dn)) {
1124 		*val = 0xFFFFFFFF;
1125 		return PCIBIOS_SET_FAILED;
1126 	}
1127 
1128 	return pnv_pci_cfg_read(pdn, where, size, val);
1129 }
1130 
1131 static int pnv_eeh_write_config(struct device_node *dn,
1132 				int where, int size, u32 val)
1133 {
1134 	struct pci_dn *pdn = PCI_DN(dn);
1135 
1136 	if (!pdn)
1137 		return PCIBIOS_DEVICE_NOT_FOUND;
1138 
1139 	if (pnv_eeh_cfg_blocked(dn))
1140 		return PCIBIOS_SET_FAILED;
1141 
1142 	return pnv_pci_cfg_write(pdn, where, size, val);
1143 }
1144 
1145 static void pnv_eeh_dump_hub_diag_common(struct OpalIoP7IOCErrorData *data)
1146 {
1147 	/* GEM */
1148 	if (data->gemXfir || data->gemRfir ||
1149 	    data->gemRirqfir || data->gemMask || data->gemRwof)
1150 		pr_info("  GEM: %016llx %016llx %016llx %016llx %016llx\n",
1151 			be64_to_cpu(data->gemXfir),
1152 			be64_to_cpu(data->gemRfir),
1153 			be64_to_cpu(data->gemRirqfir),
1154 			be64_to_cpu(data->gemMask),
1155 			be64_to_cpu(data->gemRwof));
1156 
1157 	/* LEM */
1158 	if (data->lemFir || data->lemErrMask ||
1159 	    data->lemAction0 || data->lemAction1 || data->lemWof)
1160 		pr_info("  LEM: %016llx %016llx %016llx %016llx %016llx\n",
1161 			be64_to_cpu(data->lemFir),
1162 			be64_to_cpu(data->lemErrMask),
1163 			be64_to_cpu(data->lemAction0),
1164 			be64_to_cpu(data->lemAction1),
1165 			be64_to_cpu(data->lemWof));
1166 }
1167 
1168 static void pnv_eeh_get_and_dump_hub_diag(struct pci_controller *hose)
1169 {
1170 	struct pnv_phb *phb = hose->private_data;
1171 	struct OpalIoP7IOCErrorData *data = &phb->diag.hub_diag;
1172 	long rc;
1173 
1174 	rc = opal_pci_get_hub_diag_data(phb->hub_id, data, sizeof(*data));
1175 	if (rc != OPAL_SUCCESS) {
1176 		pr_warn("%s: Failed to get HUB#%llx diag-data (%ld)\n",
1177 			__func__, phb->hub_id, rc);
1178 		return;
1179 	}
1180 
1181 	switch (data->type) {
1182 	case OPAL_P7IOC_DIAG_TYPE_RGC:
1183 		pr_info("P7IOC diag-data for RGC\n\n");
1184 		pnv_eeh_dump_hub_diag_common(data);
1185 		if (data->rgc.rgcStatus || data->rgc.rgcLdcp)
1186 			pr_info("  RGC: %016llx %016llx\n",
1187 				be64_to_cpu(data->rgc.rgcStatus),
1188 				be64_to_cpu(data->rgc.rgcLdcp));
1189 		break;
1190 	case OPAL_P7IOC_DIAG_TYPE_BI:
1191 		pr_info("P7IOC diag-data for BI %s\n\n",
1192 			data->bi.biDownbound ? "Downbound" : "Upbound");
1193 		pnv_eeh_dump_hub_diag_common(data);
1194 		if (data->bi.biLdcp0 || data->bi.biLdcp1 ||
1195 		    data->bi.biLdcp2 || data->bi.biFenceStatus)
1196 			pr_info("  BI:  %016llx %016llx %016llx %016llx\n",
1197 				be64_to_cpu(data->bi.biLdcp0),
1198 				be64_to_cpu(data->bi.biLdcp1),
1199 				be64_to_cpu(data->bi.biLdcp2),
1200 				be64_to_cpu(data->bi.biFenceStatus));
1201 		break;
1202 	case OPAL_P7IOC_DIAG_TYPE_CI:
1203 		pr_info("P7IOC diag-data for CI Port %d\n\n",
1204 			data->ci.ciPort);
1205 		pnv_eeh_dump_hub_diag_common(data);
1206 		if (data->ci.ciPortStatus || data->ci.ciPortLdcp)
1207 			pr_info("  CI:  %016llx %016llx\n",
1208 				be64_to_cpu(data->ci.ciPortStatus),
1209 				be64_to_cpu(data->ci.ciPortLdcp));
1210 		break;
1211 	case OPAL_P7IOC_DIAG_TYPE_MISC:
1212 		pr_info("P7IOC diag-data for MISC\n\n");
1213 		pnv_eeh_dump_hub_diag_common(data);
1214 		break;
1215 	case OPAL_P7IOC_DIAG_TYPE_I2C:
1216 		pr_info("P7IOC diag-data for I2C\n\n");
1217 		pnv_eeh_dump_hub_diag_common(data);
1218 		break;
1219 	default:
1220 		pr_warn("%s: Invalid type of HUB#%llx diag-data (%d)\n",
1221 			__func__, phb->hub_id, data->type);
1222 	}
1223 }
1224 
1225 static int pnv_eeh_get_pe(struct pci_controller *hose,
1226 			  u16 pe_no, struct eeh_pe **pe)
1227 {
1228 	struct pnv_phb *phb = hose->private_data;
1229 	struct pnv_ioda_pe *pnv_pe;
1230 	struct eeh_pe *dev_pe;
1231 	struct eeh_dev edev;
1232 
1233 	/*
1234 	 * If PHB supports compound PE, to fetch
1235 	 * the master PE because slave PE is invisible
1236 	 * to EEH core.
1237 	 */
1238 	pnv_pe = &phb->ioda.pe_array[pe_no];
1239 	if (pnv_pe->flags & PNV_IODA_PE_SLAVE) {
1240 		pnv_pe = pnv_pe->master;
1241 		WARN_ON(!pnv_pe ||
1242 			!(pnv_pe->flags & PNV_IODA_PE_MASTER));
1243 		pe_no = pnv_pe->pe_number;
1244 	}
1245 
1246 	/* Find the PE according to PE# */
1247 	memset(&edev, 0, sizeof(struct eeh_dev));
1248 	edev.phb = hose;
1249 	edev.pe_config_addr = pe_no;
1250 	dev_pe = eeh_pe_get(&edev);
1251 	if (!dev_pe)
1252 		return -EEXIST;
1253 
1254 	/* Freeze the (compound) PE */
1255 	*pe = dev_pe;
1256 	if (!(dev_pe->state & EEH_PE_ISOLATED))
1257 		phb->freeze_pe(phb, pe_no);
1258 
1259 	/*
1260 	 * At this point, we're sure the (compound) PE should
1261 	 * have been frozen. However, we still need poke until
1262 	 * hitting the frozen PE on top level.
1263 	 */
1264 	dev_pe = dev_pe->parent;
1265 	while (dev_pe && !(dev_pe->type & EEH_PE_PHB)) {
1266 		int ret;
1267 		int active_flags = (EEH_STATE_MMIO_ACTIVE |
1268 				    EEH_STATE_DMA_ACTIVE);
1269 
1270 		ret = eeh_ops->get_state(dev_pe, NULL);
1271 		if (ret <= 0 || (ret & active_flags) == active_flags) {
1272 			dev_pe = dev_pe->parent;
1273 			continue;
1274 		}
1275 
1276 		/* Frozen parent PE */
1277 		*pe = dev_pe;
1278 		if (!(dev_pe->state & EEH_PE_ISOLATED))
1279 			phb->freeze_pe(phb, dev_pe->addr);
1280 
1281 		/* Next one */
1282 		dev_pe = dev_pe->parent;
1283 	}
1284 
1285 	return 0;
1286 }
1287 
1288 /**
1289  * pnv_eeh_next_error - Retrieve next EEH error to handle
1290  * @pe: Affected PE
1291  *
1292  * The function is expected to be called by EEH core while it gets
1293  * special EEH event (without binding PE). The function calls to
1294  * OPAL APIs for next error to handle. The informational error is
1295  * handled internally by platform. However, the dead IOC, dead PHB,
1296  * fenced PHB and frozen PE should be handled by EEH core eventually.
1297  */
1298 static int pnv_eeh_next_error(struct eeh_pe **pe)
1299 {
1300 	struct pci_controller *hose;
1301 	struct pnv_phb *phb;
1302 	struct eeh_pe *phb_pe, *parent_pe;
1303 	__be64 frozen_pe_no;
1304 	__be16 err_type, severity;
1305 	int active_flags = (EEH_STATE_MMIO_ACTIVE | EEH_STATE_DMA_ACTIVE);
1306 	long rc;
1307 	int state, ret = EEH_NEXT_ERR_NONE;
1308 
1309 	/*
1310 	 * While running here, it's safe to purge the event queue.
1311 	 * And we should keep the cached OPAL notifier event sychronized
1312 	 * between the kernel and firmware.
1313 	 */
1314 	eeh_remove_event(NULL, false);
1315 	opal_notifier_update_evt(OPAL_EVENT_PCI_ERROR, 0x0ul);
1316 
1317 	list_for_each_entry(hose, &hose_list, list_node) {
1318 		/*
1319 		 * If the subordinate PCI buses of the PHB has been
1320 		 * removed or is exactly under error recovery, we
1321 		 * needn't take care of it any more.
1322 		 */
1323 		phb = hose->private_data;
1324 		phb_pe = eeh_phb_pe_get(hose);
1325 		if (!phb_pe || (phb_pe->state & EEH_PE_ISOLATED))
1326 			continue;
1327 
1328 		rc = opal_pci_next_error(phb->opal_id,
1329 					 &frozen_pe_no, &err_type, &severity);
1330 		if (rc != OPAL_SUCCESS) {
1331 			pr_devel("%s: Invalid return value on "
1332 				 "PHB#%x (0x%lx) from opal_pci_next_error",
1333 				 __func__, hose->global_number, rc);
1334 			continue;
1335 		}
1336 
1337 		/* If the PHB doesn't have error, stop processing */
1338 		if (be16_to_cpu(err_type) == OPAL_EEH_NO_ERROR ||
1339 		    be16_to_cpu(severity) == OPAL_EEH_SEV_NO_ERROR) {
1340 			pr_devel("%s: No error found on PHB#%x\n",
1341 				 __func__, hose->global_number);
1342 			continue;
1343 		}
1344 
1345 		/*
1346 		 * Processing the error. We're expecting the error with
1347 		 * highest priority reported upon multiple errors on the
1348 		 * specific PHB.
1349 		 */
1350 		pr_devel("%s: Error (%d, %d, %llu) on PHB#%x\n",
1351 			__func__, be16_to_cpu(err_type),
1352 			be16_to_cpu(severity), be64_to_cpu(frozen_pe_no),
1353 			hose->global_number);
1354 		switch (be16_to_cpu(err_type)) {
1355 		case OPAL_EEH_IOC_ERROR:
1356 			if (be16_to_cpu(severity) == OPAL_EEH_SEV_IOC_DEAD) {
1357 				pr_err("EEH: dead IOC detected\n");
1358 				ret = EEH_NEXT_ERR_DEAD_IOC;
1359 			} else if (be16_to_cpu(severity) == OPAL_EEH_SEV_INF) {
1360 				pr_info("EEH: IOC informative error "
1361 					"detected\n");
1362 				pnv_eeh_get_and_dump_hub_diag(hose);
1363 				ret = EEH_NEXT_ERR_NONE;
1364 			}
1365 
1366 			break;
1367 		case OPAL_EEH_PHB_ERROR:
1368 			if (be16_to_cpu(severity) == OPAL_EEH_SEV_PHB_DEAD) {
1369 				*pe = phb_pe;
1370 				pr_err("EEH: dead PHB#%x detected, "
1371 				       "location: %s\n",
1372 					hose->global_number,
1373 					eeh_pe_loc_get(phb_pe));
1374 				ret = EEH_NEXT_ERR_DEAD_PHB;
1375 			} else if (be16_to_cpu(severity) ==
1376 				   OPAL_EEH_SEV_PHB_FENCED) {
1377 				*pe = phb_pe;
1378 				pr_err("EEH: Fenced PHB#%x detected, "
1379 				       "location: %s\n",
1380 					hose->global_number,
1381 					eeh_pe_loc_get(phb_pe));
1382 				ret = EEH_NEXT_ERR_FENCED_PHB;
1383 			} else if (be16_to_cpu(severity) == OPAL_EEH_SEV_INF) {
1384 				pr_info("EEH: PHB#%x informative error "
1385 					"detected, location: %s\n",
1386 					hose->global_number,
1387 					eeh_pe_loc_get(phb_pe));
1388 				pnv_eeh_get_phb_diag(phb_pe);
1389 				pnv_pci_dump_phb_diag_data(hose, phb_pe->data);
1390 				ret = EEH_NEXT_ERR_NONE;
1391 			}
1392 
1393 			break;
1394 		case OPAL_EEH_PE_ERROR:
1395 			/*
1396 			 * If we can't find the corresponding PE, we
1397 			 * just try to unfreeze.
1398 			 */
1399 			if (pnv_eeh_get_pe(hose,
1400 				be64_to_cpu(frozen_pe_no), pe)) {
1401 				/* Try best to clear it */
1402 				pr_info("EEH: Clear non-existing PHB#%x-PE#%llx\n",
1403 					hose->global_number, frozen_pe_no);
1404 				pr_info("EEH: PHB location: %s\n",
1405 					eeh_pe_loc_get(phb_pe));
1406 				opal_pci_eeh_freeze_clear(phb->opal_id,
1407 					frozen_pe_no,
1408 					OPAL_EEH_ACTION_CLEAR_FREEZE_ALL);
1409 				ret = EEH_NEXT_ERR_NONE;
1410 			} else if ((*pe)->state & EEH_PE_ISOLATED ||
1411 				   eeh_pe_passed(*pe)) {
1412 				ret = EEH_NEXT_ERR_NONE;
1413 			} else {
1414 				pr_err("EEH: Frozen PE#%x "
1415 				       "on PHB#%x detected\n",
1416 				       (*pe)->addr,
1417 					(*pe)->phb->global_number);
1418 				pr_err("EEH: PE location: %s, "
1419 				       "PHB location: %s\n",
1420 				       eeh_pe_loc_get(*pe),
1421 				       eeh_pe_loc_get(phb_pe));
1422 				ret = EEH_NEXT_ERR_FROZEN_PE;
1423 			}
1424 
1425 			break;
1426 		default:
1427 			pr_warn("%s: Unexpected error type %d\n",
1428 				__func__, be16_to_cpu(err_type));
1429 		}
1430 
1431 		/*
1432 		 * EEH core will try recover from fenced PHB or
1433 		 * frozen PE. In the time for frozen PE, EEH core
1434 		 * enable IO path for that before collecting logs,
1435 		 * but it ruins the site. So we have to dump the
1436 		 * log in advance here.
1437 		 */
1438 		if ((ret == EEH_NEXT_ERR_FROZEN_PE  ||
1439 		    ret == EEH_NEXT_ERR_FENCED_PHB) &&
1440 		    !((*pe)->state & EEH_PE_ISOLATED)) {
1441 			eeh_pe_state_mark(*pe, EEH_PE_ISOLATED);
1442 			pnv_eeh_get_phb_diag(*pe);
1443 
1444 			if (eeh_has_flag(EEH_EARLY_DUMP_LOG))
1445 				pnv_pci_dump_phb_diag_data((*pe)->phb,
1446 							   (*pe)->data);
1447 		}
1448 
1449 		/*
1450 		 * We probably have the frozen parent PE out there and
1451 		 * we need have to handle frozen parent PE firstly.
1452 		 */
1453 		if (ret == EEH_NEXT_ERR_FROZEN_PE) {
1454 			parent_pe = (*pe)->parent;
1455 			while (parent_pe) {
1456 				/* Hit the ceiling ? */
1457 				if (parent_pe->type & EEH_PE_PHB)
1458 					break;
1459 
1460 				/* Frozen parent PE ? */
1461 				state = eeh_ops->get_state(parent_pe, NULL);
1462 				if (state > 0 &&
1463 				    (state & active_flags) != active_flags)
1464 					*pe = parent_pe;
1465 
1466 				/* Next parent level */
1467 				parent_pe = parent_pe->parent;
1468 			}
1469 
1470 			/* We possibly migrate to another PE */
1471 			eeh_pe_state_mark(*pe, EEH_PE_ISOLATED);
1472 		}
1473 
1474 		/*
1475 		 * If we have no errors on the specific PHB or only
1476 		 * informative error there, we continue poking it.
1477 		 * Otherwise, we need actions to be taken by upper
1478 		 * layer.
1479 		 */
1480 		if (ret > EEH_NEXT_ERR_INF)
1481 			break;
1482 	}
1483 
1484 	return ret;
1485 }
1486 
1487 static int pnv_eeh_restore_config(struct device_node *dn)
1488 {
1489 	struct eeh_dev *edev = of_node_to_eeh_dev(dn);
1490 	struct pnv_phb *phb;
1491 	s64 ret;
1492 
1493 	if (!edev)
1494 		return -EEXIST;
1495 
1496 	phb = edev->phb->private_data;
1497 	ret = opal_pci_reinit(phb->opal_id,
1498 			      OPAL_REINIT_PCI_DEV, edev->config_addr);
1499 	if (ret) {
1500 		pr_warn("%s: Can't reinit PCI dev 0x%x (%lld)\n",
1501 			__func__, edev->config_addr, ret);
1502 		return -EIO;
1503 	}
1504 
1505 	return 0;
1506 }
1507 
1508 static struct eeh_ops pnv_eeh_ops = {
1509 	.name                   = "powernv",
1510 	.init                   = pnv_eeh_init,
1511 	.post_init              = pnv_eeh_post_init,
1512 	.probe			= pnv_eeh_probe,
1513 	.set_option             = pnv_eeh_set_option,
1514 	.get_pe_addr            = pnv_eeh_get_pe_addr,
1515 	.get_state              = pnv_eeh_get_state,
1516 	.reset                  = pnv_eeh_reset,
1517 	.wait_state             = pnv_eeh_wait_state,
1518 	.get_log                = pnv_eeh_get_log,
1519 	.configure_bridge       = pnv_eeh_configure_bridge,
1520 	.err_inject		= pnv_eeh_err_inject,
1521 	.read_config            = pnv_eeh_read_config,
1522 	.write_config           = pnv_eeh_write_config,
1523 	.next_error		= pnv_eeh_next_error,
1524 	.restore_config		= pnv_eeh_restore_config
1525 };
1526 
1527 /**
1528  * eeh_powernv_init - Register platform dependent EEH operations
1529  *
1530  * EEH initialization on powernv platform. This function should be
1531  * called before any EEH related functions.
1532  */
1533 static int __init eeh_powernv_init(void)
1534 {
1535 	int ret = -EINVAL;
1536 
1537 	eeh_set_pe_aux_size(PNV_PCI_DIAG_BUF_SIZE);
1538 	ret = eeh_ops_register(&pnv_eeh_ops);
1539 	if (!ret)
1540 		pr_info("EEH: PowerNV platform initialized\n");
1541 	else
1542 		pr_info("EEH: Failed to initialize PowerNV platform (%d)\n", ret);
1543 
1544 	return ret;
1545 }
1546 machine_early_initcall(powernv, eeh_powernv_init);
1547