1 /*
2  * Copyright (c) 2010 - 2017 Intel Corporation.  All rights reserved.
3  * Copyright (c) 2008, 2009 QLogic Corporation. All rights reserved.
4  *
5  * This software is available to you under a choice of one of two
6  * licenses.  You may choose to be licensed under the terms of the GNU
7  * General Public License (GPL) Version 2, available from the file
8  * COPYING in the main directory of this source tree, or the
9  * OpenIB.org BSD license below:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      - Redistributions of source code must retain the above
16  *        copyright notice, this list of conditions and the following
17  *        disclaimer.
18  *
19  *      - Redistributions in binary form must reproduce the above
20  *        copyright notice, this list of conditions and the following
21  *        disclaimer in the documentation and/or other materials
22  *        provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33 
34 #include <linux/pci.h>
35 #include <linux/io.h>
36 #include <linux/delay.h>
37 #include <linux/vmalloc.h>
38 #include <linux/aer.h>
39 #include <linux/module.h>
40 
41 #include "qib.h"
42 
43 /*
44  * This file contains PCIe utility routines that are common to the
45  * various QLogic InfiniPath adapters
46  */
47 
48 /*
49  * Code to adjust PCIe capabilities.
50  * To minimize the change footprint, we call it
51  * from qib_pcie_params, which every chip-specific
52  * file calls, even though this violates some
53  * expectations of harmlessness.
54  */
55 static void qib_tune_pcie_caps(struct qib_devdata *);
56 static void qib_tune_pcie_coalesce(struct qib_devdata *);
57 
58 /*
59  * Do all the common PCIe setup and initialization.
60  * devdata is not yet allocated, and is not allocated until after this
61  * routine returns success.  Therefore qib_dev_err() can't be used for error
62  * printing.
63  */
64 int qib_pcie_init(struct pci_dev *pdev, const struct pci_device_id *ent)
65 {
66 	int ret;
67 
68 	ret = pci_enable_device(pdev);
69 	if (ret) {
70 		/*
71 		 * This can happen (in theory) iff:
72 		 * We did a chip reset, and then failed to reprogram the
73 		 * BAR, or the chip reset due to an internal error.  We then
74 		 * unloaded the driver and reloaded it.
75 		 *
76 		 * Both reset cases set the BAR back to initial state.  For
77 		 * the latter case, the AER sticky error bit at offset 0x718
78 		 * should be set, but the Linux kernel doesn't yet know
79 		 * about that, it appears.  If the original BAR was retained
80 		 * in the kernel data structures, this may be OK.
81 		 */
82 		qib_early_err(&pdev->dev, "pci enable failed: error %d\n",
83 			      -ret);
84 		goto done;
85 	}
86 
87 	ret = pci_request_regions(pdev, QIB_DRV_NAME);
88 	if (ret) {
89 		qib_devinfo(pdev, "pci_request_regions fails: err %d\n", -ret);
90 		goto bail;
91 	}
92 
93 	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
94 	if (ret) {
95 		/*
96 		 * If the 64 bit setup fails, try 32 bit.  Some systems
97 		 * do not setup 64 bit maps on systems with 2GB or less
98 		 * memory installed.
99 		 */
100 		ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
101 		if (ret) {
102 			qib_devinfo(pdev, "Unable to set DMA mask: %d\n", ret);
103 			goto bail;
104 		}
105 	}
106 
107 	pci_set_master(pdev);
108 	ret = pci_enable_pcie_error_reporting(pdev);
109 	if (ret) {
110 		qib_early_err(&pdev->dev,
111 			      "Unable to enable pcie error reporting: %d\n",
112 			      ret);
113 		ret = 0;
114 	}
115 	goto done;
116 
117 bail:
118 	pci_disable_device(pdev);
119 	pci_release_regions(pdev);
120 done:
121 	return ret;
122 }
123 
124 /*
125  * Do remaining PCIe setup, once dd is allocated, and save away
126  * fields required to re-initialize after a chip reset, or for
127  * various other purposes
128  */
129 int qib_pcie_ddinit(struct qib_devdata *dd, struct pci_dev *pdev,
130 		    const struct pci_device_id *ent)
131 {
132 	unsigned long len;
133 	resource_size_t addr;
134 
135 	dd->pcidev = pdev;
136 	pci_set_drvdata(pdev, dd);
137 
138 	addr = pci_resource_start(pdev, 0);
139 	len = pci_resource_len(pdev, 0);
140 
141 	dd->kregbase = ioremap(addr, len);
142 	if (!dd->kregbase)
143 		return -ENOMEM;
144 
145 	dd->kregend = (u64 __iomem *)((void __iomem *) dd->kregbase + len);
146 	dd->physaddr = addr;        /* used for io_remap, etc. */
147 
148 	/*
149 	 * Save BARs to rewrite after device reset.  Save all 64 bits of
150 	 * BAR, just in case.
151 	 */
152 	dd->pcibar0 = addr;
153 	dd->pcibar1 = addr >> 32;
154 	dd->deviceid = ent->device; /* save for later use */
155 	dd->vendorid = ent->vendor;
156 
157 	return 0;
158 }
159 
160 /*
161  * Do PCIe cleanup, after chip-specific cleanup, etc.  Just prior
162  * to releasing the dd memory.
163  * void because none of the core pcie cleanup returns are void
164  */
165 void qib_pcie_ddcleanup(struct qib_devdata *dd)
166 {
167 	u64 __iomem *base = (void __iomem *) dd->kregbase;
168 
169 	dd->kregbase = NULL;
170 	iounmap(base);
171 	if (dd->piobase)
172 		iounmap(dd->piobase);
173 	if (dd->userbase)
174 		iounmap(dd->userbase);
175 	if (dd->piovl15base)
176 		iounmap(dd->piovl15base);
177 
178 	pci_disable_device(dd->pcidev);
179 	pci_release_regions(dd->pcidev);
180 
181 	pci_set_drvdata(dd->pcidev, NULL);
182 }
183 
184 /*
185  * We save the msi lo and hi values, so we can restore them after
186  * chip reset (the kernel PCI infrastructure doesn't yet handle that
187  * correctly.
188  */
189 static void qib_cache_msi_info(struct qib_devdata *dd, int pos)
190 {
191 	struct pci_dev *pdev = dd->pcidev;
192 	u16 control;
193 
194 	pci_read_config_dword(pdev, pos + PCI_MSI_ADDRESS_LO, &dd->msi_lo);
195 	pci_read_config_dword(pdev, pos + PCI_MSI_ADDRESS_HI, &dd->msi_hi);
196 	pci_read_config_word(pdev, pos + PCI_MSI_FLAGS, &control);
197 
198 	/* now save the data (vector) info */
199 	pci_read_config_word(pdev,
200 			     pos + ((control & PCI_MSI_FLAGS_64BIT) ? 12 : 8),
201 			     &dd->msi_data);
202 }
203 
204 int qib_pcie_params(struct qib_devdata *dd, u32 minw, u32 *nent)
205 {
206 	u16 linkstat, speed;
207 	int nvec;
208 	int maxvec;
209 	unsigned int flags = PCI_IRQ_MSIX | PCI_IRQ_MSI;
210 
211 	if (!pci_is_pcie(dd->pcidev)) {
212 		qib_dev_err(dd, "Can't find PCI Express capability!\n");
213 		/* set up something... */
214 		dd->lbus_width = 1;
215 		dd->lbus_speed = 2500; /* Gen1, 2.5GHz */
216 		nvec = -1;
217 		goto bail;
218 	}
219 
220 	if (dd->flags & QIB_HAS_INTX)
221 		flags |= PCI_IRQ_LEGACY;
222 	maxvec = (nent && *nent) ? *nent : 1;
223 	nvec = pci_alloc_irq_vectors(dd->pcidev, 1, maxvec, flags);
224 	if (nvec < 0)
225 		goto bail;
226 
227 	/*
228 	 * If nent exists, make sure to record how many vectors were allocated.
229 	 * If msix_enabled is false, return 0 so the fallback code works
230 	 * correctly.
231 	 */
232 	if (nent)
233 		*nent = !dd->pcidev->msix_enabled ? 0 : nvec;
234 
235 	if (dd->pcidev->msi_enabled)
236 		qib_cache_msi_info(dd, dd->pcidev->msi_cap);
237 
238 	pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKSTA, &linkstat);
239 	/*
240 	 * speed is bits 0-3, linkwidth is bits 4-8
241 	 * no defines for them in headers
242 	 */
243 	speed = linkstat & 0xf;
244 	linkstat >>= 4;
245 	linkstat &= 0x1f;
246 	dd->lbus_width = linkstat;
247 
248 	switch (speed) {
249 	case 1:
250 		dd->lbus_speed = 2500; /* Gen1, 2.5GHz */
251 		break;
252 	case 2:
253 		dd->lbus_speed = 5000; /* Gen1, 5GHz */
254 		break;
255 	default: /* not defined, assume gen1 */
256 		dd->lbus_speed = 2500;
257 		break;
258 	}
259 
260 	/*
261 	 * Check against expected pcie width and complain if "wrong"
262 	 * on first initialization, not afterwards (i.e., reset).
263 	 */
264 	if (minw && linkstat < minw)
265 		qib_dev_err(dd,
266 			    "PCIe width %u (x%u HCA), performance reduced\n",
267 			    linkstat, minw);
268 
269 	qib_tune_pcie_caps(dd);
270 
271 	qib_tune_pcie_coalesce(dd);
272 
273 bail:
274 	/* fill in string, even on errors */
275 	snprintf(dd->lbus_info, sizeof(dd->lbus_info),
276 		 "PCIe,%uMHz,x%u\n", dd->lbus_speed, dd->lbus_width);
277 	return nvec < 0 ? nvec : 0;
278 }
279 
280 /**
281  * qib_free_irq - Cleanup INTx and MSI interrupts
282  * @dd: valid pointer to qib dev data
283  *
284  * Since cleanup for INTx and MSI interrupts is trivial, have a common
285  * routine.
286  *
287  */
288 void qib_free_irq(struct qib_devdata *dd)
289 {
290 	pci_free_irq(dd->pcidev, 0, dd);
291 	pci_free_irq_vectors(dd->pcidev);
292 }
293 
294 /*
295  * Setup pcie interrupt stuff again after a reset.  I'd like to just call
296  * pci_enable_msi() again for msi, but when I do that,
297  * the MSI enable bit doesn't get set in the command word, and
298  * we switch to a different interrupt vector, which is confusing,
299  * so I instead just do it all inline.  Perhaps somehow can tie this
300  * into the PCIe hotplug support at some point
301  */
302 int qib_reinit_intr(struct qib_devdata *dd)
303 {
304 	int pos;
305 	u16 control;
306 	int ret = 0;
307 
308 	/* If we aren't using MSI, don't restore it */
309 	if (!dd->msi_lo)
310 		goto bail;
311 
312 	pos = dd->pcidev->msi_cap;
313 	if (!pos) {
314 		qib_dev_err(dd,
315 			"Can't find MSI capability, can't restore MSI settings\n");
316 		ret = 0;
317 		/* nothing special for MSIx, just MSI */
318 		goto bail;
319 	}
320 	pci_write_config_dword(dd->pcidev, pos + PCI_MSI_ADDRESS_LO,
321 			       dd->msi_lo);
322 	pci_write_config_dword(dd->pcidev, pos + PCI_MSI_ADDRESS_HI,
323 			       dd->msi_hi);
324 	pci_read_config_word(dd->pcidev, pos + PCI_MSI_FLAGS, &control);
325 	if (!(control & PCI_MSI_FLAGS_ENABLE)) {
326 		control |= PCI_MSI_FLAGS_ENABLE;
327 		pci_write_config_word(dd->pcidev, pos + PCI_MSI_FLAGS,
328 				      control);
329 	}
330 	/* now rewrite the data (vector) info */
331 	pci_write_config_word(dd->pcidev, pos +
332 			      ((control & PCI_MSI_FLAGS_64BIT) ? 12 : 8),
333 			      dd->msi_data);
334 	ret = 1;
335 bail:
336 	qib_free_irq(dd);
337 
338 	if (!ret && (dd->flags & QIB_HAS_INTX))
339 		ret = 1;
340 
341 	/* and now set the pci master bit again */
342 	pci_set_master(dd->pcidev);
343 
344 	return ret;
345 }
346 
347 /*
348  * These two routines are helper routines for the device reset code
349  * to move all the pcie code out of the chip-specific driver code.
350  */
351 void qib_pcie_getcmd(struct qib_devdata *dd, u16 *cmd, u8 *iline, u8 *cline)
352 {
353 	pci_read_config_word(dd->pcidev, PCI_COMMAND, cmd);
354 	pci_read_config_byte(dd->pcidev, PCI_INTERRUPT_LINE, iline);
355 	pci_read_config_byte(dd->pcidev, PCI_CACHE_LINE_SIZE, cline);
356 }
357 
358 void qib_pcie_reenable(struct qib_devdata *dd, u16 cmd, u8 iline, u8 cline)
359 {
360 	int r;
361 
362 	r = pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_0,
363 				   dd->pcibar0);
364 	if (r)
365 		qib_dev_err(dd, "rewrite of BAR0 failed: %d\n", r);
366 	r = pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_1,
367 				   dd->pcibar1);
368 	if (r)
369 		qib_dev_err(dd, "rewrite of BAR1 failed: %d\n", r);
370 	/* now re-enable memory access, and restore cosmetic settings */
371 	pci_write_config_word(dd->pcidev, PCI_COMMAND, cmd);
372 	pci_write_config_byte(dd->pcidev, PCI_INTERRUPT_LINE, iline);
373 	pci_write_config_byte(dd->pcidev, PCI_CACHE_LINE_SIZE, cline);
374 	r = pci_enable_device(dd->pcidev);
375 	if (r)
376 		qib_dev_err(dd,
377 			"pci_enable_device failed after reset: %d\n", r);
378 }
379 
380 
381 static int qib_pcie_coalesce;
382 module_param_named(pcie_coalesce, qib_pcie_coalesce, int, S_IRUGO);
383 MODULE_PARM_DESC(pcie_coalesce, "tune PCIe coalescing on some Intel chipsets");
384 
385 /*
386  * Enable PCIe completion and data coalescing, on Intel 5x00 and 7300
387  * chipsets.   This is known to be unsafe for some revisions of some
388  * of these chipsets, with some BIOS settings, and enabling it on those
389  * systems may result in the system crashing, and/or data corruption.
390  */
391 static void qib_tune_pcie_coalesce(struct qib_devdata *dd)
392 {
393 	struct pci_dev *parent;
394 	u16 devid;
395 	u32 mask, bits, val;
396 
397 	if (!qib_pcie_coalesce)
398 		return;
399 
400 	/* Find out supported and configured values for parent (root) */
401 	parent = dd->pcidev->bus->self;
402 	if (parent->bus->parent) {
403 		qib_devinfo(dd->pcidev, "Parent not root\n");
404 		return;
405 	}
406 	if (!pci_is_pcie(parent))
407 		return;
408 	if (parent->vendor != 0x8086)
409 		return;
410 
411 	/*
412 	 *  - bit 12: Max_rdcmp_Imt_EN: need to set to 1
413 	 *  - bit 11: COALESCE_FORCE: need to set to 0
414 	 *  - bit 10: COALESCE_EN: need to set to 1
415 	 *  (but limitations on some on some chipsets)
416 	 *
417 	 *  On the Intel 5000, 5100, and 7300 chipsets, there is
418 	 *  also: - bit 25:24: COALESCE_MODE, need to set to 0
419 	 */
420 	devid = parent->device;
421 	if (devid >= 0x25e2 && devid <= 0x25fa) {
422 		/* 5000 P/V/X/Z */
423 		if (parent->revision <= 0xb2)
424 			bits = 1U << 10;
425 		else
426 			bits = 7U << 10;
427 		mask = (3U << 24) | (7U << 10);
428 	} else if (devid >= 0x65e2 && devid <= 0x65fa) {
429 		/* 5100 */
430 		bits = 1U << 10;
431 		mask = (3U << 24) | (7U << 10);
432 	} else if (devid >= 0x4021 && devid <= 0x402e) {
433 		/* 5400 */
434 		bits = 7U << 10;
435 		mask = 7U << 10;
436 	} else if (devid >= 0x3604 && devid <= 0x360a) {
437 		/* 7300 */
438 		bits = 7U << 10;
439 		mask = (3U << 24) | (7U << 10);
440 	} else {
441 		/* not one of the chipsets that we know about */
442 		return;
443 	}
444 	pci_read_config_dword(parent, 0x48, &val);
445 	val &= ~mask;
446 	val |= bits;
447 	pci_write_config_dword(parent, 0x48, val);
448 }
449 
450 /*
451  * BIOS may not set PCIe bus-utilization parameters for best performance.
452  * Check and optionally adjust them to maximize our throughput.
453  */
454 static int qib_pcie_caps;
455 module_param_named(pcie_caps, qib_pcie_caps, int, S_IRUGO);
456 MODULE_PARM_DESC(pcie_caps, "Max PCIe tuning: Payload (0..3), ReadReq (4..7)");
457 
458 static void qib_tune_pcie_caps(struct qib_devdata *dd)
459 {
460 	struct pci_dev *parent;
461 	u16 rc_mpss, rc_mps, ep_mpss, ep_mps;
462 	u16 rc_mrrs, ep_mrrs, max_mrrs;
463 
464 	/* Find out supported and configured values for parent (root) */
465 	parent = dd->pcidev->bus->self;
466 	if (!pci_is_root_bus(parent->bus)) {
467 		qib_devinfo(dd->pcidev, "Parent not root\n");
468 		return;
469 	}
470 
471 	if (!pci_is_pcie(parent) || !pci_is_pcie(dd->pcidev))
472 		return;
473 
474 	rc_mpss = parent->pcie_mpss;
475 	rc_mps = ffs(pcie_get_mps(parent)) - 8;
476 	/* Find out supported and configured values for endpoint (us) */
477 	ep_mpss = dd->pcidev->pcie_mpss;
478 	ep_mps = ffs(pcie_get_mps(dd->pcidev)) - 8;
479 
480 	/* Find max payload supported by root, endpoint */
481 	if (rc_mpss > ep_mpss)
482 		rc_mpss = ep_mpss;
483 
484 	/* If Supported greater than limit in module param, limit it */
485 	if (rc_mpss > (qib_pcie_caps & 7))
486 		rc_mpss = qib_pcie_caps & 7;
487 	/* If less than (allowed, supported), bump root payload */
488 	if (rc_mpss > rc_mps) {
489 		rc_mps = rc_mpss;
490 		pcie_set_mps(parent, 128 << rc_mps);
491 	}
492 	/* If less than (allowed, supported), bump endpoint payload */
493 	if (rc_mpss > ep_mps) {
494 		ep_mps = rc_mpss;
495 		pcie_set_mps(dd->pcidev, 128 << ep_mps);
496 	}
497 
498 	/*
499 	 * Now the Read Request size.
500 	 * No field for max supported, but PCIe spec limits it to 4096,
501 	 * which is code '5' (log2(4096) - 7)
502 	 */
503 	max_mrrs = 5;
504 	if (max_mrrs > ((qib_pcie_caps >> 4) & 7))
505 		max_mrrs = (qib_pcie_caps >> 4) & 7;
506 
507 	max_mrrs = 128 << max_mrrs;
508 	rc_mrrs = pcie_get_readrq(parent);
509 	ep_mrrs = pcie_get_readrq(dd->pcidev);
510 
511 	if (max_mrrs > rc_mrrs) {
512 		rc_mrrs = max_mrrs;
513 		pcie_set_readrq(parent, rc_mrrs);
514 	}
515 	if (max_mrrs > ep_mrrs) {
516 		ep_mrrs = max_mrrs;
517 		pcie_set_readrq(dd->pcidev, ep_mrrs);
518 	}
519 }
520 /* End of PCIe capability tuning */
521 
522 /*
523  * From here through qib_pci_err_handler definition is invoked via
524  * PCI error infrastructure, registered via pci
525  */
526 static pci_ers_result_t
527 qib_pci_error_detected(struct pci_dev *pdev, pci_channel_state_t state)
528 {
529 	struct qib_devdata *dd = pci_get_drvdata(pdev);
530 	pci_ers_result_t ret = PCI_ERS_RESULT_RECOVERED;
531 
532 	switch (state) {
533 	case pci_channel_io_normal:
534 		qib_devinfo(pdev, "State Normal, ignoring\n");
535 		break;
536 
537 	case pci_channel_io_frozen:
538 		qib_devinfo(pdev, "State Frozen, requesting reset\n");
539 		pci_disable_device(pdev);
540 		ret = PCI_ERS_RESULT_NEED_RESET;
541 		break;
542 
543 	case pci_channel_io_perm_failure:
544 		qib_devinfo(pdev, "State Permanent Failure, disabling\n");
545 		if (dd) {
546 			/* no more register accesses! */
547 			dd->flags &= ~QIB_PRESENT;
548 			qib_disable_after_error(dd);
549 		}
550 		 /* else early, or other problem */
551 		ret =  PCI_ERS_RESULT_DISCONNECT;
552 		break;
553 
554 	default: /* shouldn't happen */
555 		qib_devinfo(pdev, "QIB PCI errors detected (state %d)\n",
556 			state);
557 		break;
558 	}
559 	return ret;
560 }
561 
562 static pci_ers_result_t
563 qib_pci_mmio_enabled(struct pci_dev *pdev)
564 {
565 	u64 words = 0U;
566 	struct qib_devdata *dd = pci_get_drvdata(pdev);
567 	pci_ers_result_t ret = PCI_ERS_RESULT_RECOVERED;
568 
569 	if (dd && dd->pport) {
570 		words = dd->f_portcntr(dd->pport, QIBPORTCNTR_WORDRCV);
571 		if (words == ~0ULL)
572 			ret = PCI_ERS_RESULT_NEED_RESET;
573 	}
574 	qib_devinfo(pdev,
575 		"QIB mmio_enabled function called, read wordscntr %Lx, returning %d\n",
576 		words, ret);
577 	return  ret;
578 }
579 
580 static pci_ers_result_t
581 qib_pci_slot_reset(struct pci_dev *pdev)
582 {
583 	qib_devinfo(pdev, "QIB slot_reset function called, ignored\n");
584 	return PCI_ERS_RESULT_CAN_RECOVER;
585 }
586 
587 static void
588 qib_pci_resume(struct pci_dev *pdev)
589 {
590 	struct qib_devdata *dd = pci_get_drvdata(pdev);
591 
592 	qib_devinfo(pdev, "QIB resume function called\n");
593 	/*
594 	 * Running jobs will fail, since it's asynchronous
595 	 * unlike sysfs-requested reset.   Better than
596 	 * doing nothing.
597 	 */
598 	qib_init(dd, 1); /* same as re-init after reset */
599 }
600 
601 const struct pci_error_handlers qib_pci_err_handler = {
602 	.error_detected = qib_pci_error_detected,
603 	.mmio_enabled = qib_pci_mmio_enabled,
604 	.slot_reset = qib_pci_slot_reset,
605 	.resume = qib_pci_resume,
606 };
607