1 /*
2  * Copyright (c) 2008, 2009 QLogic Corporation. All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  */
32 
33 #include <linux/pci.h>
34 #include <linux/io.h>
35 #include <linux/delay.h>
36 #include <linux/vmalloc.h>
37 #include <linux/aer.h>
38 #include <linux/module.h>
39 
40 #include "qib.h"
41 
42 /*
43  * This file contains PCIe utility routines that are common to the
44  * various QLogic InfiniPath adapters
45  */
46 
47 /*
48  * Code to adjust PCIe capabilities.
49  * To minimize the change footprint, we call it
50  * from qib_pcie_params, which every chip-specific
51  * file calls, even though this violates some
52  * expectations of harmlessness.
53  */
54 static void qib_tune_pcie_caps(struct qib_devdata *);
55 static void qib_tune_pcie_coalesce(struct qib_devdata *);
56 
57 /*
58  * Do all the common PCIe setup and initialization.
59  * devdata is not yet allocated, and is not allocated until after this
60  * routine returns success.  Therefore qib_dev_err() can't be used for error
61  * printing.
62  */
63 int qib_pcie_init(struct pci_dev *pdev, const struct pci_device_id *ent)
64 {
65 	int ret;
66 
67 	ret = pci_enable_device(pdev);
68 	if (ret) {
69 		/*
70 		 * This can happen (in theory) iff:
71 		 * We did a chip reset, and then failed to reprogram the
72 		 * BAR, or the chip reset due to an internal error.  We then
73 		 * unloaded the driver and reloaded it.
74 		 *
75 		 * Both reset cases set the BAR back to initial state.  For
76 		 * the latter case, the AER sticky error bit at offset 0x718
77 		 * should be set, but the Linux kernel doesn't yet know
78 		 * about that, it appears.  If the original BAR was retained
79 		 * in the kernel data structures, this may be OK.
80 		 */
81 		qib_early_err(&pdev->dev, "pci enable failed: error %d\n",
82 			      -ret);
83 		goto done;
84 	}
85 
86 	ret = pci_request_regions(pdev, QIB_DRV_NAME);
87 	if (ret) {
88 		qib_devinfo(pdev, "pci_request_regions fails: err %d\n", -ret);
89 		goto bail;
90 	}
91 
92 	ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
93 	if (ret) {
94 		/*
95 		 * If the 64 bit setup fails, try 32 bit.  Some systems
96 		 * do not setup 64 bit maps on systems with 2GB or less
97 		 * memory installed.
98 		 */
99 		ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
100 		if (ret) {
101 			qib_devinfo(pdev, "Unable to set DMA mask: %d\n", ret);
102 			goto bail;
103 		}
104 		ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
105 	} else
106 		ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64));
107 	if (ret) {
108 		qib_early_err(&pdev->dev,
109 			      "Unable to set DMA consistent mask: %d\n", ret);
110 		goto bail;
111 	}
112 
113 	pci_set_master(pdev);
114 	ret = pci_enable_pcie_error_reporting(pdev);
115 	if (ret) {
116 		qib_early_err(&pdev->dev,
117 			      "Unable to enable pcie error reporting: %d\n",
118 			      ret);
119 		ret = 0;
120 	}
121 	goto done;
122 
123 bail:
124 	pci_disable_device(pdev);
125 	pci_release_regions(pdev);
126 done:
127 	return ret;
128 }
129 
130 /*
131  * Do remaining PCIe setup, once dd is allocated, and save away
132  * fields required to re-initialize after a chip reset, or for
133  * various other purposes
134  */
135 int qib_pcie_ddinit(struct qib_devdata *dd, struct pci_dev *pdev,
136 		    const struct pci_device_id *ent)
137 {
138 	unsigned long len;
139 	resource_size_t addr;
140 
141 	dd->pcidev = pdev;
142 	pci_set_drvdata(pdev, dd);
143 
144 	addr = pci_resource_start(pdev, 0);
145 	len = pci_resource_len(pdev, 0);
146 
147 #if defined(__powerpc__)
148 	/* There isn't a generic way to specify writethrough mappings */
149 	dd->kregbase = __ioremap(addr, len, _PAGE_NO_CACHE | _PAGE_WRITETHRU);
150 #else
151 	dd->kregbase = ioremap_nocache(addr, len);
152 #endif
153 
154 	if (!dd->kregbase)
155 		return -ENOMEM;
156 
157 	dd->kregend = (u64 __iomem *)((void __iomem *) dd->kregbase + len);
158 	dd->physaddr = addr;        /* used for io_remap, etc. */
159 
160 	/*
161 	 * Save BARs to rewrite after device reset.  Save all 64 bits of
162 	 * BAR, just in case.
163 	 */
164 	dd->pcibar0 = addr;
165 	dd->pcibar1 = addr >> 32;
166 	dd->deviceid = ent->device; /* save for later use */
167 	dd->vendorid = ent->vendor;
168 
169 	return 0;
170 }
171 
172 /*
173  * Do PCIe cleanup, after chip-specific cleanup, etc.  Just prior
174  * to releasing the dd memory.
175  * void because none of the core pcie cleanup returns are void
176  */
177 void qib_pcie_ddcleanup(struct qib_devdata *dd)
178 {
179 	u64 __iomem *base = (void __iomem *) dd->kregbase;
180 
181 	dd->kregbase = NULL;
182 	iounmap(base);
183 	if (dd->piobase)
184 		iounmap(dd->piobase);
185 	if (dd->userbase)
186 		iounmap(dd->userbase);
187 	if (dd->piovl15base)
188 		iounmap(dd->piovl15base);
189 
190 	pci_disable_device(dd->pcidev);
191 	pci_release_regions(dd->pcidev);
192 
193 	pci_set_drvdata(dd->pcidev, NULL);
194 }
195 
196 static void qib_msix_setup(struct qib_devdata *dd, int pos, u32 *msixcnt,
197 			   struct qib_msix_entry *qib_msix_entry)
198 {
199 	int ret;
200 	int nvec = *msixcnt;
201 	struct msix_entry *msix_entry;
202 	int i;
203 
204 	ret = pci_msix_vec_count(dd->pcidev);
205 	if (ret < 0)
206 		goto do_intx;
207 
208 	nvec = min(nvec, ret);
209 
210 	/* We can't pass qib_msix_entry array to qib_msix_setup
211 	 * so use a dummy msix_entry array and copy the allocated
212 	 * irq back to the qib_msix_entry array. */
213 	msix_entry = kcalloc(nvec, sizeof(*msix_entry), GFP_KERNEL);
214 	if (!msix_entry)
215 		goto do_intx;
216 
217 	for (i = 0; i < nvec; i++)
218 		msix_entry[i] = qib_msix_entry[i].msix;
219 
220 	ret = pci_enable_msix_range(dd->pcidev, msix_entry, 1, nvec);
221 	if (ret < 0)
222 		goto free_msix_entry;
223 	else
224 		nvec = ret;
225 
226 	for (i = 0; i < nvec; i++)
227 		qib_msix_entry[i].msix = msix_entry[i];
228 
229 	kfree(msix_entry);
230 	*msixcnt = nvec;
231 	return;
232 
233 free_msix_entry:
234 	kfree(msix_entry);
235 
236 do_intx:
237 	qib_dev_err(
238 		dd,
239 		"pci_enable_msix_range %d vectors failed: %d, falling back to INTx\n",
240 		nvec, ret);
241 	*msixcnt = 0;
242 	qib_enable_intx(dd->pcidev);
243 }
244 
245 /**
246  * We save the msi lo and hi values, so we can restore them after
247  * chip reset (the kernel PCI infrastructure doesn't yet handle that
248  * correctly.
249  */
250 static int qib_msi_setup(struct qib_devdata *dd, int pos)
251 {
252 	struct pci_dev *pdev = dd->pcidev;
253 	u16 control;
254 	int ret;
255 
256 	ret = pci_enable_msi(pdev);
257 	if (ret)
258 		qib_dev_err(dd,
259 			"pci_enable_msi failed: %d, interrupts may not work\n",
260 			ret);
261 	/* continue even if it fails, we may still be OK... */
262 
263 	pci_read_config_dword(pdev, pos + PCI_MSI_ADDRESS_LO,
264 			      &dd->msi_lo);
265 	pci_read_config_dword(pdev, pos + PCI_MSI_ADDRESS_HI,
266 			      &dd->msi_hi);
267 	pci_read_config_word(pdev, pos + PCI_MSI_FLAGS, &control);
268 	/* now save the data (vector) info */
269 	pci_read_config_word(pdev, pos + ((control & PCI_MSI_FLAGS_64BIT)
270 				    ? 12 : 8),
271 			     &dd->msi_data);
272 	return ret;
273 }
274 
275 int qib_pcie_params(struct qib_devdata *dd, u32 minw, u32 *nent,
276 		    struct qib_msix_entry *entry)
277 {
278 	u16 linkstat, speed;
279 	int pos = 0, ret = 1;
280 
281 	if (!pci_is_pcie(dd->pcidev)) {
282 		qib_dev_err(dd, "Can't find PCI Express capability!\n");
283 		/* set up something... */
284 		dd->lbus_width = 1;
285 		dd->lbus_speed = 2500; /* Gen1, 2.5GHz */
286 		goto bail;
287 	}
288 
289 	pos = dd->pcidev->msix_cap;
290 	if (nent && *nent && pos) {
291 		qib_msix_setup(dd, pos, nent, entry);
292 		ret = 0; /* did it, either MSIx or INTx */
293 	} else {
294 		pos = dd->pcidev->msi_cap;
295 		if (pos)
296 			ret = qib_msi_setup(dd, pos);
297 		else
298 			qib_dev_err(dd, "No PCI MSI or MSIx capability!\n");
299 	}
300 	if (!pos)
301 		qib_enable_intx(dd->pcidev);
302 
303 	pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKSTA, &linkstat);
304 	/*
305 	 * speed is bits 0-3, linkwidth is bits 4-8
306 	 * no defines for them in headers
307 	 */
308 	speed = linkstat & 0xf;
309 	linkstat >>= 4;
310 	linkstat &= 0x1f;
311 	dd->lbus_width = linkstat;
312 
313 	switch (speed) {
314 	case 1:
315 		dd->lbus_speed = 2500; /* Gen1, 2.5GHz */
316 		break;
317 	case 2:
318 		dd->lbus_speed = 5000; /* Gen1, 5GHz */
319 		break;
320 	default: /* not defined, assume gen1 */
321 		dd->lbus_speed = 2500;
322 		break;
323 	}
324 
325 	/*
326 	 * Check against expected pcie width and complain if "wrong"
327 	 * on first initialization, not afterwards (i.e., reset).
328 	 */
329 	if (minw && linkstat < minw)
330 		qib_dev_err(dd,
331 			    "PCIe width %u (x%u HCA), performance reduced\n",
332 			    linkstat, minw);
333 
334 	qib_tune_pcie_caps(dd);
335 
336 	qib_tune_pcie_coalesce(dd);
337 
338 bail:
339 	/* fill in string, even on errors */
340 	snprintf(dd->lbus_info, sizeof(dd->lbus_info),
341 		 "PCIe,%uMHz,x%u\n", dd->lbus_speed, dd->lbus_width);
342 	return ret;
343 }
344 
345 /*
346  * Setup pcie interrupt stuff again after a reset.  I'd like to just call
347  * pci_enable_msi() again for msi, but when I do that,
348  * the MSI enable bit doesn't get set in the command word, and
349  * we switch to to a different interrupt vector, which is confusing,
350  * so I instead just do it all inline.  Perhaps somehow can tie this
351  * into the PCIe hotplug support at some point
352  */
353 int qib_reinit_intr(struct qib_devdata *dd)
354 {
355 	int pos;
356 	u16 control;
357 	int ret = 0;
358 
359 	/* If we aren't using MSI, don't restore it */
360 	if (!dd->msi_lo)
361 		goto bail;
362 
363 	pos = dd->pcidev->msi_cap;
364 	if (!pos) {
365 		qib_dev_err(dd,
366 			"Can't find MSI capability, can't restore MSI settings\n");
367 		ret = 0;
368 		/* nothing special for MSIx, just MSI */
369 		goto bail;
370 	}
371 	pci_write_config_dword(dd->pcidev, pos + PCI_MSI_ADDRESS_LO,
372 			       dd->msi_lo);
373 	pci_write_config_dword(dd->pcidev, pos + PCI_MSI_ADDRESS_HI,
374 			       dd->msi_hi);
375 	pci_read_config_word(dd->pcidev, pos + PCI_MSI_FLAGS, &control);
376 	if (!(control & PCI_MSI_FLAGS_ENABLE)) {
377 		control |= PCI_MSI_FLAGS_ENABLE;
378 		pci_write_config_word(dd->pcidev, pos + PCI_MSI_FLAGS,
379 				      control);
380 	}
381 	/* now rewrite the data (vector) info */
382 	pci_write_config_word(dd->pcidev, pos +
383 			      ((control & PCI_MSI_FLAGS_64BIT) ? 12 : 8),
384 			      dd->msi_data);
385 	ret = 1;
386 bail:
387 	if (!ret && (dd->flags & QIB_HAS_INTX)) {
388 		qib_enable_intx(dd->pcidev);
389 		ret = 1;
390 	}
391 
392 	/* and now set the pci master bit again */
393 	pci_set_master(dd->pcidev);
394 
395 	return ret;
396 }
397 
398 /*
399  * Disable msi interrupt if enabled, and clear msi_lo.
400  * This is used primarily for the fallback to INTx, but
401  * is also used in reinit after reset, and during cleanup.
402  */
403 void qib_nomsi(struct qib_devdata *dd)
404 {
405 	dd->msi_lo = 0;
406 	pci_disable_msi(dd->pcidev);
407 }
408 
409 /*
410  * Same as qib_nosmi, but for MSIx.
411  */
412 void qib_nomsix(struct qib_devdata *dd)
413 {
414 	pci_disable_msix(dd->pcidev);
415 }
416 
417 /*
418  * Similar to pci_intx(pdev, 1), except that we make sure
419  * msi(x) is off.
420  */
421 void qib_enable_intx(struct pci_dev *pdev)
422 {
423 	u16 cw, new;
424 	int pos;
425 
426 	/* first, turn on INTx */
427 	pci_read_config_word(pdev, PCI_COMMAND, &cw);
428 	new = cw & ~PCI_COMMAND_INTX_DISABLE;
429 	if (new != cw)
430 		pci_write_config_word(pdev, PCI_COMMAND, new);
431 
432 	pos = pdev->msi_cap;
433 	if (pos) {
434 		/* then turn off MSI */
435 		pci_read_config_word(pdev, pos + PCI_MSI_FLAGS, &cw);
436 		new = cw & ~PCI_MSI_FLAGS_ENABLE;
437 		if (new != cw)
438 			pci_write_config_word(pdev, pos + PCI_MSI_FLAGS, new);
439 	}
440 	pos = pdev->msix_cap;
441 	if (pos) {
442 		/* then turn off MSIx */
443 		pci_read_config_word(pdev, pos + PCI_MSIX_FLAGS, &cw);
444 		new = cw & ~PCI_MSIX_FLAGS_ENABLE;
445 		if (new != cw)
446 			pci_write_config_word(pdev, pos + PCI_MSIX_FLAGS, new);
447 	}
448 }
449 
450 /*
451  * These two routines are helper routines for the device reset code
452  * to move all the pcie code out of the chip-specific driver code.
453  */
454 void qib_pcie_getcmd(struct qib_devdata *dd, u16 *cmd, u8 *iline, u8 *cline)
455 {
456 	pci_read_config_word(dd->pcidev, PCI_COMMAND, cmd);
457 	pci_read_config_byte(dd->pcidev, PCI_INTERRUPT_LINE, iline);
458 	pci_read_config_byte(dd->pcidev, PCI_CACHE_LINE_SIZE, cline);
459 }
460 
461 void qib_pcie_reenable(struct qib_devdata *dd, u16 cmd, u8 iline, u8 cline)
462 {
463 	int r;
464 
465 	r = pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_0,
466 				   dd->pcibar0);
467 	if (r)
468 		qib_dev_err(dd, "rewrite of BAR0 failed: %d\n", r);
469 	r = pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_1,
470 				   dd->pcibar1);
471 	if (r)
472 		qib_dev_err(dd, "rewrite of BAR1 failed: %d\n", r);
473 	/* now re-enable memory access, and restore cosmetic settings */
474 	pci_write_config_word(dd->pcidev, PCI_COMMAND, cmd);
475 	pci_write_config_byte(dd->pcidev, PCI_INTERRUPT_LINE, iline);
476 	pci_write_config_byte(dd->pcidev, PCI_CACHE_LINE_SIZE, cline);
477 	r = pci_enable_device(dd->pcidev);
478 	if (r)
479 		qib_dev_err(dd,
480 			"pci_enable_device failed after reset: %d\n", r);
481 }
482 
483 
484 static int qib_pcie_coalesce;
485 module_param_named(pcie_coalesce, qib_pcie_coalesce, int, S_IRUGO);
486 MODULE_PARM_DESC(pcie_coalesce, "tune PCIe colescing on some Intel chipsets");
487 
488 /*
489  * Enable PCIe completion and data coalescing, on Intel 5x00 and 7300
490  * chipsets.   This is known to be unsafe for some revisions of some
491  * of these chipsets, with some BIOS settings, and enabling it on those
492  * systems may result in the system crashing, and/or data corruption.
493  */
494 static void qib_tune_pcie_coalesce(struct qib_devdata *dd)
495 {
496 	int r;
497 	struct pci_dev *parent;
498 	u16 devid;
499 	u32 mask, bits, val;
500 
501 	if (!qib_pcie_coalesce)
502 		return;
503 
504 	/* Find out supported and configured values for parent (root) */
505 	parent = dd->pcidev->bus->self;
506 	if (parent->bus->parent) {
507 		qib_devinfo(dd->pcidev, "Parent not root\n");
508 		return;
509 	}
510 	if (!pci_is_pcie(parent))
511 		return;
512 	if (parent->vendor != 0x8086)
513 		return;
514 
515 	/*
516 	 *  - bit 12: Max_rdcmp_Imt_EN: need to set to 1
517 	 *  - bit 11: COALESCE_FORCE: need to set to 0
518 	 *  - bit 10: COALESCE_EN: need to set to 1
519 	 *  (but limitations on some on some chipsets)
520 	 *
521 	 *  On the Intel 5000, 5100, and 7300 chipsets, there is
522 	 *  also: - bit 25:24: COALESCE_MODE, need to set to 0
523 	 */
524 	devid = parent->device;
525 	if (devid >= 0x25e2 && devid <= 0x25fa) {
526 		/* 5000 P/V/X/Z */
527 		if (parent->revision <= 0xb2)
528 			bits = 1U << 10;
529 		else
530 			bits = 7U << 10;
531 		mask = (3U << 24) | (7U << 10);
532 	} else if (devid >= 0x65e2 && devid <= 0x65fa) {
533 		/* 5100 */
534 		bits = 1U << 10;
535 		mask = (3U << 24) | (7U << 10);
536 	} else if (devid >= 0x4021 && devid <= 0x402e) {
537 		/* 5400 */
538 		bits = 7U << 10;
539 		mask = 7U << 10;
540 	} else if (devid >= 0x3604 && devid <= 0x360a) {
541 		/* 7300 */
542 		bits = 7U << 10;
543 		mask = (3U << 24) | (7U << 10);
544 	} else {
545 		/* not one of the chipsets that we know about */
546 		return;
547 	}
548 	pci_read_config_dword(parent, 0x48, &val);
549 	val &= ~mask;
550 	val |= bits;
551 	r = pci_write_config_dword(parent, 0x48, val);
552 }
553 
554 /*
555  * BIOS may not set PCIe bus-utilization parameters for best performance.
556  * Check and optionally adjust them to maximize our throughput.
557  */
558 static int qib_pcie_caps;
559 module_param_named(pcie_caps, qib_pcie_caps, int, S_IRUGO);
560 MODULE_PARM_DESC(pcie_caps, "Max PCIe tuning: Payload (0..3), ReadReq (4..7)");
561 
562 static void qib_tune_pcie_caps(struct qib_devdata *dd)
563 {
564 	struct pci_dev *parent;
565 	u16 rc_mpss, rc_mps, ep_mpss, ep_mps;
566 	u16 rc_mrrs, ep_mrrs, max_mrrs;
567 
568 	/* Find out supported and configured values for parent (root) */
569 	parent = dd->pcidev->bus->self;
570 	if (!pci_is_root_bus(parent->bus)) {
571 		qib_devinfo(dd->pcidev, "Parent not root\n");
572 		return;
573 	}
574 
575 	if (!pci_is_pcie(parent) || !pci_is_pcie(dd->pcidev))
576 		return;
577 
578 	rc_mpss = parent->pcie_mpss;
579 	rc_mps = ffs(pcie_get_mps(parent)) - 8;
580 	/* Find out supported and configured values for endpoint (us) */
581 	ep_mpss = dd->pcidev->pcie_mpss;
582 	ep_mps = ffs(pcie_get_mps(dd->pcidev)) - 8;
583 
584 	/* Find max payload supported by root, endpoint */
585 	if (rc_mpss > ep_mpss)
586 		rc_mpss = ep_mpss;
587 
588 	/* If Supported greater than limit in module param, limit it */
589 	if (rc_mpss > (qib_pcie_caps & 7))
590 		rc_mpss = qib_pcie_caps & 7;
591 	/* If less than (allowed, supported), bump root payload */
592 	if (rc_mpss > rc_mps) {
593 		rc_mps = rc_mpss;
594 		pcie_set_mps(parent, 128 << rc_mps);
595 	}
596 	/* If less than (allowed, supported), bump endpoint payload */
597 	if (rc_mpss > ep_mps) {
598 		ep_mps = rc_mpss;
599 		pcie_set_mps(dd->pcidev, 128 << ep_mps);
600 	}
601 
602 	/*
603 	 * Now the Read Request size.
604 	 * No field for max supported, but PCIe spec limits it to 4096,
605 	 * which is code '5' (log2(4096) - 7)
606 	 */
607 	max_mrrs = 5;
608 	if (max_mrrs > ((qib_pcie_caps >> 4) & 7))
609 		max_mrrs = (qib_pcie_caps >> 4) & 7;
610 
611 	max_mrrs = 128 << max_mrrs;
612 	rc_mrrs = pcie_get_readrq(parent);
613 	ep_mrrs = pcie_get_readrq(dd->pcidev);
614 
615 	if (max_mrrs > rc_mrrs) {
616 		rc_mrrs = max_mrrs;
617 		pcie_set_readrq(parent, rc_mrrs);
618 	}
619 	if (max_mrrs > ep_mrrs) {
620 		ep_mrrs = max_mrrs;
621 		pcie_set_readrq(dd->pcidev, ep_mrrs);
622 	}
623 }
624 /* End of PCIe capability tuning */
625 
626 /*
627  * From here through qib_pci_err_handler definition is invoked via
628  * PCI error infrastructure, registered via pci
629  */
630 static pci_ers_result_t
631 qib_pci_error_detected(struct pci_dev *pdev, pci_channel_state_t state)
632 {
633 	struct qib_devdata *dd = pci_get_drvdata(pdev);
634 	pci_ers_result_t ret = PCI_ERS_RESULT_RECOVERED;
635 
636 	switch (state) {
637 	case pci_channel_io_normal:
638 		qib_devinfo(pdev, "State Normal, ignoring\n");
639 		break;
640 
641 	case pci_channel_io_frozen:
642 		qib_devinfo(pdev, "State Frozen, requesting reset\n");
643 		pci_disable_device(pdev);
644 		ret = PCI_ERS_RESULT_NEED_RESET;
645 		break;
646 
647 	case pci_channel_io_perm_failure:
648 		qib_devinfo(pdev, "State Permanent Failure, disabling\n");
649 		if (dd) {
650 			/* no more register accesses! */
651 			dd->flags &= ~QIB_PRESENT;
652 			qib_disable_after_error(dd);
653 		}
654 		 /* else early, or other problem */
655 		ret =  PCI_ERS_RESULT_DISCONNECT;
656 		break;
657 
658 	default: /* shouldn't happen */
659 		qib_devinfo(pdev, "QIB PCI errors detected (state %d)\n",
660 			state);
661 		break;
662 	}
663 	return ret;
664 }
665 
666 static pci_ers_result_t
667 qib_pci_mmio_enabled(struct pci_dev *pdev)
668 {
669 	u64 words = 0U;
670 	struct qib_devdata *dd = pci_get_drvdata(pdev);
671 	pci_ers_result_t ret = PCI_ERS_RESULT_RECOVERED;
672 
673 	if (dd && dd->pport) {
674 		words = dd->f_portcntr(dd->pport, QIBPORTCNTR_WORDRCV);
675 		if (words == ~0ULL)
676 			ret = PCI_ERS_RESULT_NEED_RESET;
677 	}
678 	qib_devinfo(pdev,
679 		"QIB mmio_enabled function called, read wordscntr %Lx, returning %d\n",
680 		words, ret);
681 	return  ret;
682 }
683 
684 static pci_ers_result_t
685 qib_pci_slot_reset(struct pci_dev *pdev)
686 {
687 	qib_devinfo(pdev, "QIB slot_reset function called, ignored\n");
688 	return PCI_ERS_RESULT_CAN_RECOVER;
689 }
690 
691 static pci_ers_result_t
692 qib_pci_link_reset(struct pci_dev *pdev)
693 {
694 	qib_devinfo(pdev, "QIB link_reset function called, ignored\n");
695 	return PCI_ERS_RESULT_CAN_RECOVER;
696 }
697 
698 static void
699 qib_pci_resume(struct pci_dev *pdev)
700 {
701 	struct qib_devdata *dd = pci_get_drvdata(pdev);
702 
703 	qib_devinfo(pdev, "QIB resume function called\n");
704 	pci_cleanup_aer_uncorrect_error_status(pdev);
705 	/*
706 	 * Running jobs will fail, since it's asynchronous
707 	 * unlike sysfs-requested reset.   Better than
708 	 * doing nothing.
709 	 */
710 	qib_init(dd, 1); /* same as re-init after reset */
711 }
712 
713 const struct pci_error_handlers qib_pci_err_handler = {
714 	.error_detected = qib_pci_error_detected,
715 	.mmio_enabled = qib_pci_mmio_enabled,
716 	.link_reset = qib_pci_link_reset,
717 	.slot_reset = qib_pci_slot_reset,
718 	.resume = qib_pci_resume,
719 };
720