xref: /openbmc/linux/drivers/infiniband/hw/hfi1/pcie.c (revision 65417d9f)
1 /*
2  * Copyright(c) 2015 - 2017 Intel Corporation.
3  *
4  * This file is provided under a dual BSD/GPLv2 license.  When using or
5  * redistributing this file, you may do so under either license.
6  *
7  * GPL LICENSE SUMMARY
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of version 2 of the GNU General Public License as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  * BSD LICENSE
19  *
20  * Redistribution and use in source and binary forms, with or without
21  * modification, are permitted provided that the following conditions
22  * are met:
23  *
24  *  - Redistributions of source code must retain the above copyright
25  *    notice, this list of conditions and the following disclaimer.
26  *  - Redistributions in binary form must reproduce the above copyright
27  *    notice, this list of conditions and the following disclaimer in
28  *    the documentation and/or other materials provided with the
29  *    distribution.
30  *  - Neither the name of Intel Corporation nor the names of its
31  *    contributors may be used to endorse or promote products derived
32  *    from this software without specific prior written permission.
33  *
34  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
35  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
36  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
37  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
38  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
39  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
40  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
41  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
42  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
43  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
44  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
45  *
46  */
47 
48 #include <linux/pci.h>
49 #include <linux/io.h>
50 #include <linux/delay.h>
51 #include <linux/vmalloc.h>
52 #include <linux/aer.h>
53 #include <linux/module.h>
54 
55 #include "hfi.h"
56 #include "chip_registers.h"
57 #include "aspm.h"
58 
59 /* link speed vector for Gen3 speed - not in Linux headers */
60 #define GEN1_SPEED_VECTOR 0x1
61 #define GEN2_SPEED_VECTOR 0x2
62 #define GEN3_SPEED_VECTOR 0x3
63 
64 /*
65  * This file contains PCIe utility routines.
66  */
67 
68 /*
69  * Code to adjust PCIe capabilities.
70  */
71 static void tune_pcie_caps(struct hfi1_devdata *);
72 
73 /*
74  * Do all the common PCIe setup and initialization.
75  * devdata is not yet allocated, and is not allocated until after this
76  * routine returns success.  Therefore dd_dev_err() can't be used for error
77  * printing.
78  */
79 int hfi1_pcie_init(struct pci_dev *pdev, const struct pci_device_id *ent)
80 {
81 	int ret;
82 
83 	ret = pci_enable_device(pdev);
84 	if (ret) {
85 		/*
86 		 * This can happen (in theory) iff:
87 		 * We did a chip reset, and then failed to reprogram the
88 		 * BAR, or the chip reset due to an internal error.  We then
89 		 * unloaded the driver and reloaded it.
90 		 *
91 		 * Both reset cases set the BAR back to initial state.  For
92 		 * the latter case, the AER sticky error bit at offset 0x718
93 		 * should be set, but the Linux kernel doesn't yet know
94 		 * about that, it appears.  If the original BAR was retained
95 		 * in the kernel data structures, this may be OK.
96 		 */
97 		hfi1_early_err(&pdev->dev, "pci enable failed: error %d\n",
98 			       -ret);
99 		goto done;
100 	}
101 
102 	ret = pci_request_regions(pdev, DRIVER_NAME);
103 	if (ret) {
104 		hfi1_early_err(&pdev->dev,
105 			       "pci_request_regions fails: err %d\n", -ret);
106 		goto bail;
107 	}
108 
109 	ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
110 	if (ret) {
111 		/*
112 		 * If the 64 bit setup fails, try 32 bit.  Some systems
113 		 * do not setup 64 bit maps on systems with 2GB or less
114 		 * memory installed.
115 		 */
116 		ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
117 		if (ret) {
118 			hfi1_early_err(&pdev->dev,
119 				       "Unable to set DMA mask: %d\n", ret);
120 			goto bail;
121 		}
122 		ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
123 	} else {
124 		ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64));
125 	}
126 	if (ret) {
127 		hfi1_early_err(&pdev->dev,
128 			       "Unable to set DMA consistent mask: %d\n", ret);
129 		goto bail;
130 	}
131 
132 	pci_set_master(pdev);
133 	(void)pci_enable_pcie_error_reporting(pdev);
134 	goto done;
135 
136 bail:
137 	hfi1_pcie_cleanup(pdev);
138 done:
139 	return ret;
140 }
141 
142 /*
143  * Clean what was done in hfi1_pcie_init()
144  */
145 void hfi1_pcie_cleanup(struct pci_dev *pdev)
146 {
147 	pci_disable_device(pdev);
148 	/*
149 	 * Release regions should be called after the disable. OK to
150 	 * call if request regions has not been called or failed.
151 	 */
152 	pci_release_regions(pdev);
153 }
154 
155 /*
156  * Do remaining PCIe setup, once dd is allocated, and save away
157  * fields required to re-initialize after a chip reset, or for
158  * various other purposes
159  */
160 int hfi1_pcie_ddinit(struct hfi1_devdata *dd, struct pci_dev *pdev)
161 {
162 	unsigned long len;
163 	resource_size_t addr;
164 	int ret = 0;
165 
166 	dd->pcidev = pdev;
167 	pci_set_drvdata(pdev, dd);
168 
169 	addr = pci_resource_start(pdev, 0);
170 	len = pci_resource_len(pdev, 0);
171 
172 	/*
173 	 * The TXE PIO buffers are at the tail end of the chip space.
174 	 * Cut them off and map them separately.
175 	 */
176 
177 	/* sanity check vs expectations */
178 	if (len != TXE_PIO_SEND + TXE_PIO_SIZE) {
179 		dd_dev_err(dd, "chip PIO range does not match\n");
180 		return -EINVAL;
181 	}
182 
183 	dd->kregbase1 = ioremap_nocache(addr, RCV_ARRAY);
184 	if (!dd->kregbase1) {
185 		dd_dev_err(dd, "UC mapping of kregbase1 failed\n");
186 		return -ENOMEM;
187 	}
188 	dd_dev_info(dd, "UC base1: %p for %x\n", dd->kregbase1, RCV_ARRAY);
189 	dd->chip_rcv_array_count = readq(dd->kregbase1 + RCV_ARRAY_CNT);
190 	dd_dev_info(dd, "RcvArray count: %u\n", dd->chip_rcv_array_count);
191 	dd->base2_start  = RCV_ARRAY + dd->chip_rcv_array_count * 8;
192 
193 	dd->kregbase2 = ioremap_nocache(
194 		addr + dd->base2_start,
195 		TXE_PIO_SEND - dd->base2_start);
196 	if (!dd->kregbase2) {
197 		dd_dev_err(dd, "UC mapping of kregbase2 failed\n");
198 		goto nomem;
199 	}
200 	dd_dev_info(dd, "UC base2: %p for %x\n", dd->kregbase2,
201 		    TXE_PIO_SEND - dd->base2_start);
202 
203 	dd->piobase = ioremap_wc(addr + TXE_PIO_SEND, TXE_PIO_SIZE);
204 	if (!dd->piobase) {
205 		dd_dev_err(dd, "WC mapping of send buffers failed\n");
206 		goto nomem;
207 	}
208 	dd_dev_info(dd, "WC piobase: %p\n for %x", dd->piobase, TXE_PIO_SIZE);
209 
210 	dd->physaddr = addr;        /* used for io_remap, etc. */
211 
212 	/*
213 	 * Map the chip's RcvArray as write-combining to allow us
214 	 * to write an entire cacheline worth of entries in one shot.
215 	 */
216 	dd->rcvarray_wc = ioremap_wc(addr + RCV_ARRAY,
217 				     dd->chip_rcv_array_count * 8);
218 	if (!dd->rcvarray_wc) {
219 		dd_dev_err(dd, "WC mapping of receive array failed\n");
220 		goto nomem;
221 	}
222 	dd_dev_info(dd, "WC RcvArray: %p for %x\n",
223 		    dd->rcvarray_wc, dd->chip_rcv_array_count * 8);
224 
225 	dd->flags |= HFI1_PRESENT;	/* chip.c CSR routines now work */
226 	return 0;
227 nomem:
228 	ret = -ENOMEM;
229 	hfi1_pcie_ddcleanup(dd);
230 	return ret;
231 }
232 
233 /*
234  * Do PCIe cleanup related to dd, after chip-specific cleanup, etc.  Just prior
235  * to releasing the dd memory.
236  * Void because all of the core pcie cleanup functions are void.
237  */
238 void hfi1_pcie_ddcleanup(struct hfi1_devdata *dd)
239 {
240 	dd->flags &= ~HFI1_PRESENT;
241 	if (dd->kregbase1)
242 		iounmap(dd->kregbase1);
243 	dd->kregbase1 = NULL;
244 	if (dd->kregbase2)
245 		iounmap(dd->kregbase2);
246 	dd->kregbase2 = NULL;
247 	if (dd->rcvarray_wc)
248 		iounmap(dd->rcvarray_wc);
249 	dd->rcvarray_wc = NULL;
250 	if (dd->piobase)
251 		iounmap(dd->piobase);
252 	dd->piobase = NULL;
253 }
254 
255 /* return the PCIe link speed from the given link status */
256 static u32 extract_speed(u16 linkstat)
257 {
258 	u32 speed;
259 
260 	switch (linkstat & PCI_EXP_LNKSTA_CLS) {
261 	default: /* not defined, assume Gen1 */
262 	case PCI_EXP_LNKSTA_CLS_2_5GB:
263 		speed = 2500; /* Gen 1, 2.5GHz */
264 		break;
265 	case PCI_EXP_LNKSTA_CLS_5_0GB:
266 		speed = 5000; /* Gen 2, 5GHz */
267 		break;
268 	case GEN3_SPEED_VECTOR:
269 		speed = 8000; /* Gen 3, 8GHz */
270 		break;
271 	}
272 	return speed;
273 }
274 
275 /* return the PCIe link speed from the given link status */
276 static u32 extract_width(u16 linkstat)
277 {
278 	return (linkstat & PCI_EXP_LNKSTA_NLW) >> PCI_EXP_LNKSTA_NLW_SHIFT;
279 }
280 
281 /* read the link status and set dd->{lbus_width,lbus_speed,lbus_info} */
282 static void update_lbus_info(struct hfi1_devdata *dd)
283 {
284 	u16 linkstat;
285 	int ret;
286 
287 	ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKSTA, &linkstat);
288 	if (ret) {
289 		dd_dev_err(dd, "Unable to read from PCI config\n");
290 		return;
291 	}
292 
293 	dd->lbus_width = extract_width(linkstat);
294 	dd->lbus_speed = extract_speed(linkstat);
295 	snprintf(dd->lbus_info, sizeof(dd->lbus_info),
296 		 "PCIe,%uMHz,x%u", dd->lbus_speed, dd->lbus_width);
297 }
298 
299 /*
300  * Read in the current PCIe link width and speed.  Find if the link is
301  * Gen3 capable.
302  */
303 int pcie_speeds(struct hfi1_devdata *dd)
304 {
305 	u32 linkcap;
306 	struct pci_dev *parent = dd->pcidev->bus->self;
307 	int ret;
308 
309 	if (!pci_is_pcie(dd->pcidev)) {
310 		dd_dev_err(dd, "Can't find PCI Express capability!\n");
311 		return -EINVAL;
312 	}
313 
314 	/* find if our max speed is Gen3 and parent supports Gen3 speeds */
315 	dd->link_gen3_capable = 1;
316 
317 	ret = pcie_capability_read_dword(dd->pcidev, PCI_EXP_LNKCAP, &linkcap);
318 	if (ret) {
319 		dd_dev_err(dd, "Unable to read from PCI config\n");
320 		return ret;
321 	}
322 
323 	if ((linkcap & PCI_EXP_LNKCAP_SLS) != GEN3_SPEED_VECTOR) {
324 		dd_dev_info(dd,
325 			    "This HFI is not Gen3 capable, max speed 0x%x, need 0x3\n",
326 			    linkcap & PCI_EXP_LNKCAP_SLS);
327 		dd->link_gen3_capable = 0;
328 	}
329 
330 	/*
331 	 * bus->max_bus_speed is set from the bridge's linkcap Max Link Speed
332 	 */
333 	if (parent && dd->pcidev->bus->max_bus_speed != PCIE_SPEED_8_0GT) {
334 		dd_dev_info(dd, "Parent PCIe bridge does not support Gen3\n");
335 		dd->link_gen3_capable = 0;
336 	}
337 
338 	/* obtain the link width and current speed */
339 	update_lbus_info(dd);
340 
341 	dd_dev_info(dd, "%s\n", dd->lbus_info);
342 
343 	return 0;
344 }
345 
346 /*
347  * Returns:
348  *	- actual number of interrupts allocated or
349  *	- 0 if fell back to INTx.
350  *      - error
351  */
352 int request_msix(struct hfi1_devdata *dd, u32 msireq)
353 {
354 	int nvec;
355 
356 	nvec = pci_alloc_irq_vectors(dd->pcidev, 1, msireq,
357 				     PCI_IRQ_MSIX | PCI_IRQ_LEGACY);
358 	if (nvec < 0) {
359 		dd_dev_err(dd, "pci_alloc_irq_vectors() failed: %d\n", nvec);
360 		return nvec;
361 	}
362 
363 	tune_pcie_caps(dd);
364 
365 	/* check for legacy IRQ */
366 	if (nvec == 1 && !dd->pcidev->msix_enabled)
367 		return 0;
368 
369 	return nvec;
370 }
371 
372 /* restore command and BARs after a reset has wiped them out */
373 int restore_pci_variables(struct hfi1_devdata *dd)
374 {
375 	int ret = 0;
376 
377 	ret = pci_write_config_word(dd->pcidev, PCI_COMMAND, dd->pci_command);
378 	if (ret)
379 		goto error;
380 
381 	ret = pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_0,
382 				     dd->pcibar0);
383 	if (ret)
384 		goto error;
385 
386 	ret = pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_1,
387 				     dd->pcibar1);
388 	if (ret)
389 		goto error;
390 
391 	ret = pci_write_config_dword(dd->pcidev, PCI_ROM_ADDRESS, dd->pci_rom);
392 	if (ret)
393 		goto error;
394 
395 	ret = pcie_capability_write_word(dd->pcidev, PCI_EXP_DEVCTL,
396 					 dd->pcie_devctl);
397 	if (ret)
398 		goto error;
399 
400 	ret = pcie_capability_write_word(dd->pcidev, PCI_EXP_LNKCTL,
401 					 dd->pcie_lnkctl);
402 	if (ret)
403 		goto error;
404 
405 	ret = pcie_capability_write_word(dd->pcidev, PCI_EXP_DEVCTL2,
406 					 dd->pcie_devctl2);
407 	if (ret)
408 		goto error;
409 
410 	ret = pci_write_config_dword(dd->pcidev, PCI_CFG_MSIX0, dd->pci_msix0);
411 	if (ret)
412 		goto error;
413 
414 	ret = pci_write_config_dword(dd->pcidev, PCIE_CFG_SPCIE1,
415 				     dd->pci_lnkctl3);
416 	if (ret)
417 		goto error;
418 
419 	ret = pci_write_config_dword(dd->pcidev, PCIE_CFG_TPH2, dd->pci_tph2);
420 	if (ret)
421 		goto error;
422 
423 	return 0;
424 
425 error:
426 	dd_dev_err(dd, "Unable to write to PCI config\n");
427 	return ret;
428 }
429 
430 /* Save BARs and command to rewrite after device reset */
431 int save_pci_variables(struct hfi1_devdata *dd)
432 {
433 	int ret = 0;
434 
435 	ret = pci_read_config_dword(dd->pcidev, PCI_BASE_ADDRESS_0,
436 				    &dd->pcibar0);
437 	if (ret)
438 		goto error;
439 
440 	ret = pci_read_config_dword(dd->pcidev, PCI_BASE_ADDRESS_1,
441 				    &dd->pcibar1);
442 	if (ret)
443 		goto error;
444 
445 	ret = pci_read_config_dword(dd->pcidev, PCI_ROM_ADDRESS, &dd->pci_rom);
446 	if (ret)
447 		goto error;
448 
449 	ret = pci_read_config_word(dd->pcidev, PCI_COMMAND, &dd->pci_command);
450 	if (ret)
451 		goto error;
452 
453 	ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL,
454 					&dd->pcie_devctl);
455 	if (ret)
456 		goto error;
457 
458 	ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKCTL,
459 					&dd->pcie_lnkctl);
460 	if (ret)
461 		goto error;
462 
463 	ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL2,
464 					&dd->pcie_devctl2);
465 	if (ret)
466 		goto error;
467 
468 	ret = pci_read_config_dword(dd->pcidev, PCI_CFG_MSIX0, &dd->pci_msix0);
469 	if (ret)
470 		goto error;
471 
472 	ret = pci_read_config_dword(dd->pcidev, PCIE_CFG_SPCIE1,
473 				    &dd->pci_lnkctl3);
474 	if (ret)
475 		goto error;
476 
477 	ret = pci_read_config_dword(dd->pcidev, PCIE_CFG_TPH2, &dd->pci_tph2);
478 	if (ret)
479 		goto error;
480 
481 	return 0;
482 
483 error:
484 	dd_dev_err(dd, "Unable to read from PCI config\n");
485 	return ret;
486 }
487 
488 /*
489  * BIOS may not set PCIe bus-utilization parameters for best performance.
490  * Check and optionally adjust them to maximize our throughput.
491  */
492 static int hfi1_pcie_caps;
493 module_param_named(pcie_caps, hfi1_pcie_caps, int, S_IRUGO);
494 MODULE_PARM_DESC(pcie_caps, "Max PCIe tuning: Payload (0..3), ReadReq (4..7)");
495 
496 uint aspm_mode = ASPM_MODE_DISABLED;
497 module_param_named(aspm, aspm_mode, uint, S_IRUGO);
498 MODULE_PARM_DESC(aspm, "PCIe ASPM: 0: disable, 1: enable, 2: dynamic");
499 
500 static void tune_pcie_caps(struct hfi1_devdata *dd)
501 {
502 	struct pci_dev *parent;
503 	u16 rc_mpss, rc_mps, ep_mpss, ep_mps;
504 	u16 rc_mrrs, ep_mrrs, max_mrrs, ectl;
505 	int ret;
506 
507 	/*
508 	 * Turn on extended tags in DevCtl in case the BIOS has turned it off
509 	 * to improve WFR SDMA bandwidth
510 	 */
511 	ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL, &ectl);
512 	if ((!ret) && !(ectl & PCI_EXP_DEVCTL_EXT_TAG)) {
513 		dd_dev_info(dd, "Enabling PCIe extended tags\n");
514 		ectl |= PCI_EXP_DEVCTL_EXT_TAG;
515 		ret = pcie_capability_write_word(dd->pcidev,
516 						 PCI_EXP_DEVCTL, ectl);
517 		if (ret)
518 			dd_dev_info(dd, "Unable to write to PCI config\n");
519 	}
520 	/* Find out supported and configured values for parent (root) */
521 	parent = dd->pcidev->bus->self;
522 	/*
523 	 * The driver cannot perform the tuning if it does not have
524 	 * access to the upstream component.
525 	 */
526 	if (!parent) {
527 		dd_dev_info(dd, "Parent not found\n");
528 		return;
529 	}
530 	if (!pci_is_root_bus(parent->bus)) {
531 		dd_dev_info(dd, "Parent not root\n");
532 		return;
533 	}
534 	if (!pci_is_pcie(parent)) {
535 		dd_dev_info(dd, "Parent is not PCI Express capable\n");
536 		return;
537 	}
538 	if (!pci_is_pcie(dd->pcidev)) {
539 		dd_dev_info(dd, "PCI device is not PCI Express capable\n");
540 		return;
541 	}
542 	rc_mpss = parent->pcie_mpss;
543 	rc_mps = ffs(pcie_get_mps(parent)) - 8;
544 	/* Find out supported and configured values for endpoint (us) */
545 	ep_mpss = dd->pcidev->pcie_mpss;
546 	ep_mps = ffs(pcie_get_mps(dd->pcidev)) - 8;
547 
548 	/* Find max payload supported by root, endpoint */
549 	if (rc_mpss > ep_mpss)
550 		rc_mpss = ep_mpss;
551 
552 	/* If Supported greater than limit in module param, limit it */
553 	if (rc_mpss > (hfi1_pcie_caps & 7))
554 		rc_mpss = hfi1_pcie_caps & 7;
555 	/* If less than (allowed, supported), bump root payload */
556 	if (rc_mpss > rc_mps) {
557 		rc_mps = rc_mpss;
558 		pcie_set_mps(parent, 128 << rc_mps);
559 	}
560 	/* If less than (allowed, supported), bump endpoint payload */
561 	if (rc_mpss > ep_mps) {
562 		ep_mps = rc_mpss;
563 		pcie_set_mps(dd->pcidev, 128 << ep_mps);
564 	}
565 
566 	/*
567 	 * Now the Read Request size.
568 	 * No field for max supported, but PCIe spec limits it to 4096,
569 	 * which is code '5' (log2(4096) - 7)
570 	 */
571 	max_mrrs = 5;
572 	if (max_mrrs > ((hfi1_pcie_caps >> 4) & 7))
573 		max_mrrs = (hfi1_pcie_caps >> 4) & 7;
574 
575 	max_mrrs = 128 << max_mrrs;
576 	rc_mrrs = pcie_get_readrq(parent);
577 	ep_mrrs = pcie_get_readrq(dd->pcidev);
578 
579 	if (max_mrrs > rc_mrrs) {
580 		rc_mrrs = max_mrrs;
581 		pcie_set_readrq(parent, rc_mrrs);
582 	}
583 	if (max_mrrs > ep_mrrs) {
584 		ep_mrrs = max_mrrs;
585 		pcie_set_readrq(dd->pcidev, ep_mrrs);
586 	}
587 }
588 
589 /* End of PCIe capability tuning */
590 
591 /*
592  * From here through hfi1_pci_err_handler definition is invoked via
593  * PCI error infrastructure, registered via pci
594  */
595 static pci_ers_result_t
596 pci_error_detected(struct pci_dev *pdev, pci_channel_state_t state)
597 {
598 	struct hfi1_devdata *dd = pci_get_drvdata(pdev);
599 	pci_ers_result_t ret = PCI_ERS_RESULT_RECOVERED;
600 
601 	switch (state) {
602 	case pci_channel_io_normal:
603 		dd_dev_info(dd, "State Normal, ignoring\n");
604 		break;
605 
606 	case pci_channel_io_frozen:
607 		dd_dev_info(dd, "State Frozen, requesting reset\n");
608 		pci_disable_device(pdev);
609 		ret = PCI_ERS_RESULT_NEED_RESET;
610 		break;
611 
612 	case pci_channel_io_perm_failure:
613 		if (dd) {
614 			dd_dev_info(dd, "State Permanent Failure, disabling\n");
615 			/* no more register accesses! */
616 			dd->flags &= ~HFI1_PRESENT;
617 			hfi1_disable_after_error(dd);
618 		}
619 		 /* else early, or other problem */
620 		ret =  PCI_ERS_RESULT_DISCONNECT;
621 		break;
622 
623 	default: /* shouldn't happen */
624 		dd_dev_info(dd, "HFI1 PCI errors detected (state %d)\n",
625 			    state);
626 		break;
627 	}
628 	return ret;
629 }
630 
631 static pci_ers_result_t
632 pci_mmio_enabled(struct pci_dev *pdev)
633 {
634 	u64 words = 0U;
635 	struct hfi1_devdata *dd = pci_get_drvdata(pdev);
636 	pci_ers_result_t ret = PCI_ERS_RESULT_RECOVERED;
637 
638 	if (dd && dd->pport) {
639 		words = read_port_cntr(dd->pport, C_RX_WORDS, CNTR_INVALID_VL);
640 		if (words == ~0ULL)
641 			ret = PCI_ERS_RESULT_NEED_RESET;
642 		dd_dev_info(dd,
643 			    "HFI1 mmio_enabled function called, read wordscntr %llx, returning %d\n",
644 			    words, ret);
645 	}
646 	return  ret;
647 }
648 
649 static pci_ers_result_t
650 pci_slot_reset(struct pci_dev *pdev)
651 {
652 	struct hfi1_devdata *dd = pci_get_drvdata(pdev);
653 
654 	dd_dev_info(dd, "HFI1 slot_reset function called, ignored\n");
655 	return PCI_ERS_RESULT_CAN_RECOVER;
656 }
657 
658 static void
659 pci_resume(struct pci_dev *pdev)
660 {
661 	struct hfi1_devdata *dd = pci_get_drvdata(pdev);
662 
663 	dd_dev_info(dd, "HFI1 resume function called\n");
664 	pci_cleanup_aer_uncorrect_error_status(pdev);
665 	/*
666 	 * Running jobs will fail, since it's asynchronous
667 	 * unlike sysfs-requested reset.   Better than
668 	 * doing nothing.
669 	 */
670 	hfi1_init(dd, 1); /* same as re-init after reset */
671 }
672 
673 const struct pci_error_handlers hfi1_pci_err_handler = {
674 	.error_detected = pci_error_detected,
675 	.mmio_enabled = pci_mmio_enabled,
676 	.slot_reset = pci_slot_reset,
677 	.resume = pci_resume,
678 };
679 
680 /*============================================================================*/
681 /* PCIe Gen3 support */
682 
683 /*
684  * This code is separated out because it is expected to be removed in the
685  * final shipping product.  If not, then it will be revisited and items
686  * will be moved to more standard locations.
687  */
688 
689 /* ASIC_PCI_SD_HOST_STATUS.FW_DNLD_STS field values */
690 #define DL_STATUS_HFI0 0x1	/* hfi0 firmware download complete */
691 #define DL_STATUS_HFI1 0x2	/* hfi1 firmware download complete */
692 #define DL_STATUS_BOTH 0x3	/* hfi0 and hfi1 firmware download complete */
693 
694 /* ASIC_PCI_SD_HOST_STATUS.FW_DNLD_ERR field values */
695 #define DL_ERR_NONE		0x0	/* no error */
696 #define DL_ERR_SWAP_PARITY	0x1	/* parity error in SerDes interrupt */
697 					/*   or response data */
698 #define DL_ERR_DISABLED	0x2	/* hfi disabled */
699 #define DL_ERR_SECURITY	0x3	/* security check failed */
700 #define DL_ERR_SBUS		0x4	/* SBus status error */
701 #define DL_ERR_XFR_PARITY	0x5	/* parity error during ROM transfer*/
702 
703 /* gasket block secondary bus reset delay */
704 #define SBR_DELAY_US 200000	/* 200ms */
705 
706 /* mask for PCIe capability register lnkctl2 target link speed */
707 #define LNKCTL2_TARGET_LINK_SPEED_MASK 0xf
708 
709 static uint pcie_target = 3;
710 module_param(pcie_target, uint, S_IRUGO);
711 MODULE_PARM_DESC(pcie_target, "PCIe target speed (0 skip, 1-3 Gen1-3)");
712 
713 static uint pcie_force;
714 module_param(pcie_force, uint, S_IRUGO);
715 MODULE_PARM_DESC(pcie_force, "Force driver to do a PCIe firmware download even if already at target speed");
716 
717 static uint pcie_retry = 5;
718 module_param(pcie_retry, uint, S_IRUGO);
719 MODULE_PARM_DESC(pcie_retry, "Driver will try this many times to reach requested speed");
720 
721 #define UNSET_PSET 255
722 #define DEFAULT_DISCRETE_PSET 2	/* discrete HFI */
723 #define DEFAULT_MCP_PSET 6	/* MCP HFI */
724 static uint pcie_pset = UNSET_PSET;
725 module_param(pcie_pset, uint, S_IRUGO);
726 MODULE_PARM_DESC(pcie_pset, "PCIe Eq Pset value to use, range is 0-10");
727 
728 static uint pcie_ctle = 3; /* discrete on, integrated on */
729 module_param(pcie_ctle, uint, S_IRUGO);
730 MODULE_PARM_DESC(pcie_ctle, "PCIe static CTLE mode, bit 0 - discrete on/off, bit 1 - integrated on/off");
731 
732 /* equalization columns */
733 #define PREC 0
734 #define ATTN 1
735 #define POST 2
736 
737 /* discrete silicon preliminary equalization values */
738 static const u8 discrete_preliminary_eq[11][3] = {
739 	/* prec   attn   post */
740 	{  0x00,  0x00,  0x12 },	/* p0 */
741 	{  0x00,  0x00,  0x0c },	/* p1 */
742 	{  0x00,  0x00,  0x0f },	/* p2 */
743 	{  0x00,  0x00,  0x09 },	/* p3 */
744 	{  0x00,  0x00,  0x00 },	/* p4 */
745 	{  0x06,  0x00,  0x00 },	/* p5 */
746 	{  0x09,  0x00,  0x00 },	/* p6 */
747 	{  0x06,  0x00,  0x0f },	/* p7 */
748 	{  0x09,  0x00,  0x09 },	/* p8 */
749 	{  0x0c,  0x00,  0x00 },	/* p9 */
750 	{  0x00,  0x00,  0x18 },	/* p10 */
751 };
752 
753 /* integrated silicon preliminary equalization values */
754 static const u8 integrated_preliminary_eq[11][3] = {
755 	/* prec   attn   post */
756 	{  0x00,  0x1e,  0x07 },	/* p0 */
757 	{  0x00,  0x1e,  0x05 },	/* p1 */
758 	{  0x00,  0x1e,  0x06 },	/* p2 */
759 	{  0x00,  0x1e,  0x04 },	/* p3 */
760 	{  0x00,  0x1e,  0x00 },	/* p4 */
761 	{  0x03,  0x1e,  0x00 },	/* p5 */
762 	{  0x04,  0x1e,  0x00 },	/* p6 */
763 	{  0x03,  0x1e,  0x06 },	/* p7 */
764 	{  0x03,  0x1e,  0x04 },	/* p8 */
765 	{  0x05,  0x1e,  0x00 },	/* p9 */
766 	{  0x00,  0x1e,  0x0a },	/* p10 */
767 };
768 
769 static const u8 discrete_ctle_tunings[11][4] = {
770 	/* DC     LF     HF     BW */
771 	{  0x48,  0x0b,  0x04,  0x04 },	/* p0 */
772 	{  0x60,  0x05,  0x0f,  0x0a },	/* p1 */
773 	{  0x50,  0x09,  0x06,  0x06 },	/* p2 */
774 	{  0x68,  0x05,  0x0f,  0x0a },	/* p3 */
775 	{  0x80,  0x05,  0x0f,  0x0a },	/* p4 */
776 	{  0x70,  0x05,  0x0f,  0x0a },	/* p5 */
777 	{  0x68,  0x05,  0x0f,  0x0a },	/* p6 */
778 	{  0x38,  0x0f,  0x00,  0x00 },	/* p7 */
779 	{  0x48,  0x09,  0x06,  0x06 },	/* p8 */
780 	{  0x60,  0x05,  0x0f,  0x0a },	/* p9 */
781 	{  0x38,  0x0f,  0x00,  0x00 },	/* p10 */
782 };
783 
784 static const u8 integrated_ctle_tunings[11][4] = {
785 	/* DC     LF     HF     BW */
786 	{  0x38,  0x0f,  0x00,  0x00 },	/* p0 */
787 	{  0x38,  0x0f,  0x00,  0x00 },	/* p1 */
788 	{  0x38,  0x0f,  0x00,  0x00 },	/* p2 */
789 	{  0x38,  0x0f,  0x00,  0x00 },	/* p3 */
790 	{  0x58,  0x0a,  0x05,  0x05 },	/* p4 */
791 	{  0x48,  0x0a,  0x05,  0x05 },	/* p5 */
792 	{  0x40,  0x0a,  0x05,  0x05 },	/* p6 */
793 	{  0x38,  0x0f,  0x00,  0x00 },	/* p7 */
794 	{  0x38,  0x0f,  0x00,  0x00 },	/* p8 */
795 	{  0x38,  0x09,  0x06,  0x06 },	/* p9 */
796 	{  0x38,  0x0e,  0x01,  0x01 },	/* p10 */
797 };
798 
799 /* helper to format the value to write to hardware */
800 #define eq_value(pre, curr, post) \
801 	((((u32)(pre)) << \
802 			PCIE_CFG_REG_PL102_GEN3_EQ_PRE_CURSOR_PSET_SHIFT) \
803 	| (((u32)(curr)) << PCIE_CFG_REG_PL102_GEN3_EQ_CURSOR_PSET_SHIFT) \
804 	| (((u32)(post)) << \
805 		PCIE_CFG_REG_PL102_GEN3_EQ_POST_CURSOR_PSET_SHIFT))
806 
807 /*
808  * Load the given EQ preset table into the PCIe hardware.
809  */
810 static int load_eq_table(struct hfi1_devdata *dd, const u8 eq[11][3], u8 fs,
811 			 u8 div)
812 {
813 	struct pci_dev *pdev = dd->pcidev;
814 	u32 hit_error = 0;
815 	u32 violation;
816 	u32 i;
817 	u8 c_minus1, c0, c_plus1;
818 	int ret;
819 
820 	for (i = 0; i < 11; i++) {
821 		/* set index */
822 		pci_write_config_dword(pdev, PCIE_CFG_REG_PL103, i);
823 		/* write the value */
824 		c_minus1 = eq[i][PREC] / div;
825 		c0 = fs - (eq[i][PREC] / div) - (eq[i][POST] / div);
826 		c_plus1 = eq[i][POST] / div;
827 		pci_write_config_dword(pdev, PCIE_CFG_REG_PL102,
828 				       eq_value(c_minus1, c0, c_plus1));
829 		/* check if these coefficients violate EQ rules */
830 		ret = pci_read_config_dword(dd->pcidev,
831 					    PCIE_CFG_REG_PL105, &violation);
832 		if (ret) {
833 			dd_dev_err(dd, "Unable to read from PCI config\n");
834 			hit_error = 1;
835 			break;
836 		}
837 
838 		if (violation
839 		    & PCIE_CFG_REG_PL105_GEN3_EQ_VIOLATE_COEF_RULES_SMASK){
840 			if (hit_error == 0) {
841 				dd_dev_err(dd,
842 					   "Gen3 EQ Table Coefficient rule violations\n");
843 				dd_dev_err(dd, "         prec   attn   post\n");
844 			}
845 			dd_dev_err(dd, "   p%02d:   %02x     %02x     %02x\n",
846 				   i, (u32)eq[i][0], (u32)eq[i][1],
847 				   (u32)eq[i][2]);
848 			dd_dev_err(dd, "            %02x     %02x     %02x\n",
849 				   (u32)c_minus1, (u32)c0, (u32)c_plus1);
850 			hit_error = 1;
851 		}
852 	}
853 	if (hit_error)
854 		return -EINVAL;
855 	return 0;
856 }
857 
858 /*
859  * Steps to be done after the PCIe firmware is downloaded and
860  * before the SBR for the Pcie Gen3.
861  * The SBus resource is already being held.
862  */
863 static void pcie_post_steps(struct hfi1_devdata *dd)
864 {
865 	int i;
866 
867 	set_sbus_fast_mode(dd);
868 	/*
869 	 * Write to the PCIe PCSes to set the G3_LOCKED_NEXT bits to 1.
870 	 * This avoids a spurious framing error that can otherwise be
871 	 * generated by the MAC layer.
872 	 *
873 	 * Use individual addresses since no broadcast is set up.
874 	 */
875 	for (i = 0; i < NUM_PCIE_SERDES; i++) {
876 		sbus_request(dd, pcie_pcs_addrs[dd->hfi1_id][i],
877 			     0x03, WRITE_SBUS_RECEIVER, 0x00022132);
878 	}
879 
880 	clear_sbus_fast_mode(dd);
881 }
882 
883 /*
884  * Trigger a secondary bus reset (SBR) on ourselves using our parent.
885  *
886  * Based on pci_parent_bus_reset() which is not exported by the
887  * kernel core.
888  */
889 static int trigger_sbr(struct hfi1_devdata *dd)
890 {
891 	struct pci_dev *dev = dd->pcidev;
892 	struct pci_dev *pdev;
893 
894 	/* need a parent */
895 	if (!dev->bus->self) {
896 		dd_dev_err(dd, "%s: no parent device\n", __func__);
897 		return -ENOTTY;
898 	}
899 
900 	/* should not be anyone else on the bus */
901 	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
902 		if (pdev != dev) {
903 			dd_dev_err(dd,
904 				   "%s: another device is on the same bus\n",
905 				   __func__);
906 			return -ENOTTY;
907 		}
908 
909 	/*
910 	 * A secondary bus reset (SBR) issues a hot reset to our device.
911 	 * The following routine does a 1s wait after the reset is dropped
912 	 * per PCI Trhfa (recovery time).  PCIe 3.0 section 6.6.1 -
913 	 * Conventional Reset, paragraph 3, line 35 also says that a 1s
914 	 * delay after a reset is required.  Per spec requirements,
915 	 * the link is either working or not after that point.
916 	 */
917 	pci_reset_bridge_secondary_bus(dev->bus->self);
918 
919 	return 0;
920 }
921 
922 /*
923  * Write the given gasket interrupt register.
924  */
925 static void write_gasket_interrupt(struct hfi1_devdata *dd, int index,
926 				   u16 code, u16 data)
927 {
928 	write_csr(dd, ASIC_PCIE_SD_INTRPT_LIST + (index * 8),
929 		  (((u64)code << ASIC_PCIE_SD_INTRPT_LIST_INTRPT_CODE_SHIFT) |
930 		   ((u64)data << ASIC_PCIE_SD_INTRPT_LIST_INTRPT_DATA_SHIFT)));
931 }
932 
933 /*
934  * Tell the gasket logic how to react to the reset.
935  */
936 static void arm_gasket_logic(struct hfi1_devdata *dd)
937 {
938 	u64 reg;
939 
940 	reg = (((u64)1 << dd->hfi1_id) <<
941 	       ASIC_PCIE_SD_HOST_CMD_INTRPT_CMD_SHIFT) |
942 	      ((u64)pcie_serdes_broadcast[dd->hfi1_id] <<
943 	       ASIC_PCIE_SD_HOST_CMD_SBUS_RCVR_ADDR_SHIFT |
944 	       ASIC_PCIE_SD_HOST_CMD_SBR_MODE_SMASK |
945 	       ((u64)SBR_DELAY_US & ASIC_PCIE_SD_HOST_CMD_TIMER_MASK) <<
946 	       ASIC_PCIE_SD_HOST_CMD_TIMER_SHIFT);
947 	write_csr(dd, ASIC_PCIE_SD_HOST_CMD, reg);
948 	/* read back to push the write */
949 	read_csr(dd, ASIC_PCIE_SD_HOST_CMD);
950 }
951 
952 /*
953  * CCE_PCIE_CTRL long name helpers
954  * We redefine these shorter macros to use in the code while leaving
955  * chip_registers.h to be autogenerated from the hardware spec.
956  */
957 #define LANE_BUNDLE_MASK              CCE_PCIE_CTRL_PCIE_LANE_BUNDLE_MASK
958 #define LANE_BUNDLE_SHIFT             CCE_PCIE_CTRL_PCIE_LANE_BUNDLE_SHIFT
959 #define LANE_DELAY_MASK               CCE_PCIE_CTRL_PCIE_LANE_DELAY_MASK
960 #define LANE_DELAY_SHIFT              CCE_PCIE_CTRL_PCIE_LANE_DELAY_SHIFT
961 #define MARGIN_OVERWRITE_ENABLE_SHIFT CCE_PCIE_CTRL_XMT_MARGIN_OVERWRITE_ENABLE_SHIFT
962 #define MARGIN_SHIFT                  CCE_PCIE_CTRL_XMT_MARGIN_SHIFT
963 #define MARGIN_G1_G2_OVERWRITE_MASK   CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_OVERWRITE_ENABLE_MASK
964 #define MARGIN_G1_G2_OVERWRITE_SHIFT  CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_OVERWRITE_ENABLE_SHIFT
965 #define MARGIN_GEN1_GEN2_MASK         CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_MASK
966 #define MARGIN_GEN1_GEN2_SHIFT        CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_SHIFT
967 
968  /*
969   * Write xmt_margin for full-swing (WFR-B) or half-swing (WFR-C).
970   */
971 static void write_xmt_margin(struct hfi1_devdata *dd, const char *fname)
972 {
973 	u64 pcie_ctrl;
974 	u64 xmt_margin;
975 	u64 xmt_margin_oe;
976 	u64 lane_delay;
977 	u64 lane_bundle;
978 
979 	pcie_ctrl = read_csr(dd, CCE_PCIE_CTRL);
980 
981 	/*
982 	 * For Discrete, use full-swing.
983 	 *  - PCIe TX defaults to full-swing.
984 	 *    Leave this register as default.
985 	 * For Integrated, use half-swing
986 	 *  - Copy xmt_margin and xmt_margin_oe
987 	 *    from Gen1/Gen2 to Gen3.
988 	 */
989 	if (dd->pcidev->device == PCI_DEVICE_ID_INTEL1) { /* integrated */
990 		/* extract initial fields */
991 		xmt_margin = (pcie_ctrl >> MARGIN_GEN1_GEN2_SHIFT)
992 			      & MARGIN_GEN1_GEN2_MASK;
993 		xmt_margin_oe = (pcie_ctrl >> MARGIN_G1_G2_OVERWRITE_SHIFT)
994 				 & MARGIN_G1_G2_OVERWRITE_MASK;
995 		lane_delay = (pcie_ctrl >> LANE_DELAY_SHIFT) & LANE_DELAY_MASK;
996 		lane_bundle = (pcie_ctrl >> LANE_BUNDLE_SHIFT)
997 			       & LANE_BUNDLE_MASK;
998 
999 		/*
1000 		 * For A0, EFUSE values are not set.  Override with the
1001 		 * correct values.
1002 		 */
1003 		if (is_ax(dd)) {
1004 			/*
1005 			 * xmt_margin and OverwiteEnabel should be the
1006 			 * same for Gen1/Gen2 and Gen3
1007 			 */
1008 			xmt_margin = 0x5;
1009 			xmt_margin_oe = 0x1;
1010 			lane_delay = 0xF; /* Delay 240ns. */
1011 			lane_bundle = 0x0; /* Set to 1 lane. */
1012 		}
1013 
1014 		/* overwrite existing values */
1015 		pcie_ctrl = (xmt_margin << MARGIN_GEN1_GEN2_SHIFT)
1016 			| (xmt_margin_oe << MARGIN_G1_G2_OVERWRITE_SHIFT)
1017 			| (xmt_margin << MARGIN_SHIFT)
1018 			| (xmt_margin_oe << MARGIN_OVERWRITE_ENABLE_SHIFT)
1019 			| (lane_delay << LANE_DELAY_SHIFT)
1020 			| (lane_bundle << LANE_BUNDLE_SHIFT);
1021 
1022 		write_csr(dd, CCE_PCIE_CTRL, pcie_ctrl);
1023 	}
1024 
1025 	dd_dev_dbg(dd, "%s: program XMT margin, CcePcieCtrl 0x%llx\n",
1026 		   fname, pcie_ctrl);
1027 }
1028 
1029 /*
1030  * Do all the steps needed to transition the PCIe link to Gen3 speed.
1031  */
1032 int do_pcie_gen3_transition(struct hfi1_devdata *dd)
1033 {
1034 	struct pci_dev *parent = dd->pcidev->bus->self;
1035 	u64 fw_ctrl;
1036 	u64 reg, therm;
1037 	u32 reg32, fs, lf;
1038 	u32 status, err;
1039 	int ret;
1040 	int do_retry, retry_count = 0;
1041 	int intnum = 0;
1042 	uint default_pset;
1043 	u16 target_vector, target_speed;
1044 	u16 lnkctl2, vendor;
1045 	u8 div;
1046 	const u8 (*eq)[3];
1047 	const u8 (*ctle_tunings)[4];
1048 	uint static_ctle_mode;
1049 	int return_error = 0;
1050 
1051 	/* PCIe Gen3 is for the ASIC only */
1052 	if (dd->icode != ICODE_RTL_SILICON)
1053 		return 0;
1054 
1055 	if (pcie_target == 1) {			/* target Gen1 */
1056 		target_vector = GEN1_SPEED_VECTOR;
1057 		target_speed = 2500;
1058 	} else if (pcie_target == 2) {		/* target Gen2 */
1059 		target_vector = GEN2_SPEED_VECTOR;
1060 		target_speed = 5000;
1061 	} else if (pcie_target == 3) {		/* target Gen3 */
1062 		target_vector = GEN3_SPEED_VECTOR;
1063 		target_speed = 8000;
1064 	} else {
1065 		/* off or invalid target - skip */
1066 		dd_dev_info(dd, "%s: Skipping PCIe transition\n", __func__);
1067 		return 0;
1068 	}
1069 
1070 	/* if already at target speed, done (unless forced) */
1071 	if (dd->lbus_speed == target_speed) {
1072 		dd_dev_info(dd, "%s: PCIe already at gen%d, %s\n", __func__,
1073 			    pcie_target,
1074 			    pcie_force ? "re-doing anyway" : "skipping");
1075 		if (!pcie_force)
1076 			return 0;
1077 	}
1078 
1079 	/*
1080 	 * The driver cannot do the transition if it has no access to the
1081 	 * upstream component
1082 	 */
1083 	if (!parent) {
1084 		dd_dev_info(dd, "%s: No upstream, Can't do gen3 transition\n",
1085 			    __func__);
1086 		return 0;
1087 	}
1088 
1089 	/*
1090 	 * Do the Gen3 transition.  Steps are those of the PCIe Gen3
1091 	 * recipe.
1092 	 */
1093 
1094 	/* step 1: pcie link working in gen1/gen2 */
1095 
1096 	/* step 2: if either side is not capable of Gen3, done */
1097 	if (pcie_target == 3 && !dd->link_gen3_capable) {
1098 		dd_dev_err(dd, "The PCIe link is not Gen3 capable\n");
1099 		ret = -ENOSYS;
1100 		goto done_no_mutex;
1101 	}
1102 
1103 	/* hold the SBus resource across the firmware download and SBR */
1104 	ret = acquire_chip_resource(dd, CR_SBUS, SBUS_TIMEOUT);
1105 	if (ret) {
1106 		dd_dev_err(dd, "%s: unable to acquire SBus resource\n",
1107 			   __func__);
1108 		return ret;
1109 	}
1110 
1111 	/* make sure thermal polling is not causing interrupts */
1112 	therm = read_csr(dd, ASIC_CFG_THERM_POLL_EN);
1113 	if (therm) {
1114 		write_csr(dd, ASIC_CFG_THERM_POLL_EN, 0x0);
1115 		msleep(100);
1116 		dd_dev_info(dd, "%s: Disabled therm polling\n",
1117 			    __func__);
1118 	}
1119 
1120 retry:
1121 	/* the SBus download will reset the spico for thermal */
1122 
1123 	/* step 3: download SBus Master firmware */
1124 	/* step 4: download PCIe Gen3 SerDes firmware */
1125 	dd_dev_info(dd, "%s: downloading firmware\n", __func__);
1126 	ret = load_pcie_firmware(dd);
1127 	if (ret) {
1128 		/* do not proceed if the firmware cannot be downloaded */
1129 		return_error = 1;
1130 		goto done;
1131 	}
1132 
1133 	/* step 5: set up device parameter settings */
1134 	dd_dev_info(dd, "%s: setting PCIe registers\n", __func__);
1135 
1136 	/*
1137 	 * PcieCfgSpcie1 - Link Control 3
1138 	 * Leave at reset value.  No need to set PerfEq - link equalization
1139 	 * will be performed automatically after the SBR when the target
1140 	 * speed is 8GT/s.
1141 	 */
1142 
1143 	/* clear all 16 per-lane error bits (PCIe: Lane Error Status) */
1144 	pci_write_config_dword(dd->pcidev, PCIE_CFG_SPCIE2, 0xffff);
1145 
1146 	/* step 5a: Set Synopsys Port Logic registers */
1147 
1148 	/*
1149 	 * PcieCfgRegPl2 - Port Force Link
1150 	 *
1151 	 * Set the low power field to 0x10 to avoid unnecessary power
1152 	 * management messages.  All other fields are zero.
1153 	 */
1154 	reg32 = 0x10ul << PCIE_CFG_REG_PL2_LOW_PWR_ENT_CNT_SHIFT;
1155 	pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL2, reg32);
1156 
1157 	/*
1158 	 * PcieCfgRegPl100 - Gen3 Control
1159 	 *
1160 	 * turn off PcieCfgRegPl100.Gen3ZRxDcNonCompl
1161 	 * turn on PcieCfgRegPl100.EqEieosCnt
1162 	 * Everything else zero.
1163 	 */
1164 	reg32 = PCIE_CFG_REG_PL100_EQ_EIEOS_CNT_SMASK;
1165 	pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL100, reg32);
1166 
1167 	/*
1168 	 * PcieCfgRegPl101 - Gen3 EQ FS and LF
1169 	 * PcieCfgRegPl102 - Gen3 EQ Presets to Coefficients Mapping
1170 	 * PcieCfgRegPl103 - Gen3 EQ Preset Index
1171 	 * PcieCfgRegPl105 - Gen3 EQ Status
1172 	 *
1173 	 * Give initial EQ settings.
1174 	 */
1175 	if (dd->pcidev->device == PCI_DEVICE_ID_INTEL0) { /* discrete */
1176 		/* 1000mV, FS=24, LF = 8 */
1177 		fs = 24;
1178 		lf = 8;
1179 		div = 3;
1180 		eq = discrete_preliminary_eq;
1181 		default_pset = DEFAULT_DISCRETE_PSET;
1182 		ctle_tunings = discrete_ctle_tunings;
1183 		/* bit 0 - discrete on/off */
1184 		static_ctle_mode = pcie_ctle & 0x1;
1185 	} else {
1186 		/* 400mV, FS=29, LF = 9 */
1187 		fs = 29;
1188 		lf = 9;
1189 		div = 1;
1190 		eq = integrated_preliminary_eq;
1191 		default_pset = DEFAULT_MCP_PSET;
1192 		ctle_tunings = integrated_ctle_tunings;
1193 		/* bit 1 - integrated on/off */
1194 		static_ctle_mode = (pcie_ctle >> 1) & 0x1;
1195 	}
1196 	pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL101,
1197 			       (fs <<
1198 				PCIE_CFG_REG_PL101_GEN3_EQ_LOCAL_FS_SHIFT) |
1199 			       (lf <<
1200 				PCIE_CFG_REG_PL101_GEN3_EQ_LOCAL_LF_SHIFT));
1201 	ret = load_eq_table(dd, eq, fs, div);
1202 	if (ret)
1203 		goto done;
1204 
1205 	/*
1206 	 * PcieCfgRegPl106 - Gen3 EQ Control
1207 	 *
1208 	 * Set Gen3EqPsetReqVec, leave other fields 0.
1209 	 */
1210 	if (pcie_pset == UNSET_PSET)
1211 		pcie_pset = default_pset;
1212 	if (pcie_pset > 10) {	/* valid range is 0-10, inclusive */
1213 		dd_dev_err(dd, "%s: Invalid Eq Pset %u, setting to %d\n",
1214 			   __func__, pcie_pset, default_pset);
1215 		pcie_pset = default_pset;
1216 	}
1217 	dd_dev_info(dd, "%s: using EQ Pset %u\n", __func__, pcie_pset);
1218 	pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL106,
1219 			       ((1 << pcie_pset) <<
1220 			PCIE_CFG_REG_PL106_GEN3_EQ_PSET_REQ_VEC_SHIFT) |
1221 			PCIE_CFG_REG_PL106_GEN3_EQ_EVAL2MS_DISABLE_SMASK |
1222 			PCIE_CFG_REG_PL106_GEN3_EQ_PHASE23_EXIT_MODE_SMASK);
1223 
1224 	/*
1225 	 * step 5b: Do post firmware download steps via SBus
1226 	 */
1227 	dd_dev_info(dd, "%s: doing pcie post steps\n", __func__);
1228 	pcie_post_steps(dd);
1229 
1230 	/*
1231 	 * step 5c: Program gasket interrupts
1232 	 */
1233 	/* set the Rx Bit Rate to REFCLK ratio */
1234 	write_gasket_interrupt(dd, intnum++, 0x0006, 0x0050);
1235 	/* disable pCal for PCIe Gen3 RX equalization */
1236 	/* select adaptive or static CTLE */
1237 	write_gasket_interrupt(dd, intnum++, 0x0026,
1238 			       0x5b01 | (static_ctle_mode << 3));
1239 	/*
1240 	 * Enable iCal for PCIe Gen3 RX equalization, and set which
1241 	 * evaluation of RX_EQ_EVAL will launch the iCal procedure.
1242 	 */
1243 	write_gasket_interrupt(dd, intnum++, 0x0026, 0x5202);
1244 
1245 	if (static_ctle_mode) {
1246 		/* apply static CTLE tunings */
1247 		u8 pcie_dc, pcie_lf, pcie_hf, pcie_bw;
1248 
1249 		pcie_dc = ctle_tunings[pcie_pset][0];
1250 		pcie_lf = ctle_tunings[pcie_pset][1];
1251 		pcie_hf = ctle_tunings[pcie_pset][2];
1252 		pcie_bw = ctle_tunings[pcie_pset][3];
1253 		write_gasket_interrupt(dd, intnum++, 0x0026, 0x0200 | pcie_dc);
1254 		write_gasket_interrupt(dd, intnum++, 0x0026, 0x0100 | pcie_lf);
1255 		write_gasket_interrupt(dd, intnum++, 0x0026, 0x0000 | pcie_hf);
1256 		write_gasket_interrupt(dd, intnum++, 0x0026, 0x5500 | pcie_bw);
1257 	}
1258 
1259 	/* terminate list */
1260 	write_gasket_interrupt(dd, intnum++, 0x0000, 0x0000);
1261 
1262 	/*
1263 	 * step 5d: program XMT margin
1264 	 */
1265 	write_xmt_margin(dd, __func__);
1266 
1267 	/*
1268 	 * step 5e: disable active state power management (ASPM). It
1269 	 * will be enabled if required later
1270 	 */
1271 	dd_dev_info(dd, "%s: clearing ASPM\n", __func__);
1272 	aspm_hw_disable_l1(dd);
1273 
1274 	/*
1275 	 * step 5f: clear DirectSpeedChange
1276 	 * PcieCfgRegPl67.DirectSpeedChange must be zero to prevent the
1277 	 * change in the speed target from starting before we are ready.
1278 	 * This field defaults to 0 and we are not changing it, so nothing
1279 	 * needs to be done.
1280 	 */
1281 
1282 	/* step 5g: Set target link speed */
1283 	/*
1284 	 * Set target link speed to be target on both device and parent.
1285 	 * On setting the parent: Some system BIOSs "helpfully" set the
1286 	 * parent target speed to Gen2 to match the ASIC's initial speed.
1287 	 * We can set the target Gen3 because we have already checked
1288 	 * that it is Gen3 capable earlier.
1289 	 */
1290 	dd_dev_info(dd, "%s: setting parent target link speed\n", __func__);
1291 	ret = pcie_capability_read_word(parent, PCI_EXP_LNKCTL2, &lnkctl2);
1292 	if (ret) {
1293 		dd_dev_err(dd, "Unable to read from PCI config\n");
1294 		return_error = 1;
1295 		goto done;
1296 	}
1297 
1298 	dd_dev_info(dd, "%s: ..old link control2: 0x%x\n", __func__,
1299 		    (u32)lnkctl2);
1300 	/* only write to parent if target is not as high as ours */
1301 	if ((lnkctl2 & LNKCTL2_TARGET_LINK_SPEED_MASK) < target_vector) {
1302 		lnkctl2 &= ~LNKCTL2_TARGET_LINK_SPEED_MASK;
1303 		lnkctl2 |= target_vector;
1304 		dd_dev_info(dd, "%s: ..new link control2: 0x%x\n", __func__,
1305 			    (u32)lnkctl2);
1306 		ret = pcie_capability_write_word(parent,
1307 						 PCI_EXP_LNKCTL2, lnkctl2);
1308 		if (ret) {
1309 			dd_dev_err(dd, "Unable to write to PCI config\n");
1310 			return_error = 1;
1311 			goto done;
1312 		}
1313 	} else {
1314 		dd_dev_info(dd, "%s: ..target speed is OK\n", __func__);
1315 	}
1316 
1317 	dd_dev_info(dd, "%s: setting target link speed\n", __func__);
1318 	ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKCTL2, &lnkctl2);
1319 	if (ret) {
1320 		dd_dev_err(dd, "Unable to read from PCI config\n");
1321 		return_error = 1;
1322 		goto done;
1323 	}
1324 
1325 	dd_dev_info(dd, "%s: ..old link control2: 0x%x\n", __func__,
1326 		    (u32)lnkctl2);
1327 	lnkctl2 &= ~LNKCTL2_TARGET_LINK_SPEED_MASK;
1328 	lnkctl2 |= target_vector;
1329 	dd_dev_info(dd, "%s: ..new link control2: 0x%x\n", __func__,
1330 		    (u32)lnkctl2);
1331 	ret = pcie_capability_write_word(dd->pcidev, PCI_EXP_LNKCTL2, lnkctl2);
1332 	if (ret) {
1333 		dd_dev_err(dd, "Unable to write to PCI config\n");
1334 		return_error = 1;
1335 		goto done;
1336 	}
1337 
1338 	/* step 5h: arm gasket logic */
1339 	/* hold DC in reset across the SBR */
1340 	write_csr(dd, CCE_DC_CTRL, CCE_DC_CTRL_DC_RESET_SMASK);
1341 	(void)read_csr(dd, CCE_DC_CTRL); /* DC reset hold */
1342 	/* save firmware control across the SBR */
1343 	fw_ctrl = read_csr(dd, MISC_CFG_FW_CTRL);
1344 
1345 	dd_dev_info(dd, "%s: arming gasket logic\n", __func__);
1346 	arm_gasket_logic(dd);
1347 
1348 	/*
1349 	 * step 6: quiesce PCIe link
1350 	 * The chip has already been reset, so there will be no traffic
1351 	 * from the chip.  Linux has no easy way to enforce that it will
1352 	 * not try to access the device, so we just need to hope it doesn't
1353 	 * do it while we are doing the reset.
1354 	 */
1355 
1356 	/*
1357 	 * step 7: initiate the secondary bus reset (SBR)
1358 	 * step 8: hardware brings the links back up
1359 	 * step 9: wait for link speed transition to be complete
1360 	 */
1361 	dd_dev_info(dd, "%s: calling trigger_sbr\n", __func__);
1362 	ret = trigger_sbr(dd);
1363 	if (ret)
1364 		goto done;
1365 
1366 	/* step 10: decide what to do next */
1367 
1368 	/* check if we can read PCI space */
1369 	ret = pci_read_config_word(dd->pcidev, PCI_VENDOR_ID, &vendor);
1370 	if (ret) {
1371 		dd_dev_info(dd,
1372 			    "%s: read of VendorID failed after SBR, err %d\n",
1373 			    __func__, ret);
1374 		return_error = 1;
1375 		goto done;
1376 	}
1377 	if (vendor == 0xffff) {
1378 		dd_dev_info(dd, "%s: VendorID is all 1s after SBR\n", __func__);
1379 		return_error = 1;
1380 		ret = -EIO;
1381 		goto done;
1382 	}
1383 
1384 	/* restore PCI space registers we know were reset */
1385 	dd_dev_info(dd, "%s: calling restore_pci_variables\n", __func__);
1386 	ret = restore_pci_variables(dd);
1387 	if (ret) {
1388 		dd_dev_err(dd, "%s: Could not restore PCI variables\n",
1389 			   __func__);
1390 		return_error = 1;
1391 		goto done;
1392 	}
1393 
1394 	/* restore firmware control */
1395 	write_csr(dd, MISC_CFG_FW_CTRL, fw_ctrl);
1396 
1397 	/*
1398 	 * Check the gasket block status.
1399 	 *
1400 	 * This is the first CSR read after the SBR.  If the read returns
1401 	 * all 1s (fails), the link did not make it back.
1402 	 *
1403 	 * Once we're sure we can read and write, clear the DC reset after
1404 	 * the SBR.  Then check for any per-lane errors. Then look over
1405 	 * the status.
1406 	 */
1407 	reg = read_csr(dd, ASIC_PCIE_SD_HOST_STATUS);
1408 	dd_dev_info(dd, "%s: gasket block status: 0x%llx\n", __func__, reg);
1409 	if (reg == ~0ull) {	/* PCIe read failed/timeout */
1410 		dd_dev_err(dd, "SBR failed - unable to read from device\n");
1411 		return_error = 1;
1412 		ret = -ENOSYS;
1413 		goto done;
1414 	}
1415 
1416 	/* clear the DC reset */
1417 	write_csr(dd, CCE_DC_CTRL, 0);
1418 
1419 	/* Set the LED off */
1420 	setextled(dd, 0);
1421 
1422 	/* check for any per-lane errors */
1423 	ret = pci_read_config_dword(dd->pcidev, PCIE_CFG_SPCIE2, &reg32);
1424 	if (ret) {
1425 		dd_dev_err(dd, "Unable to read from PCI config\n");
1426 		return_error = 1;
1427 		goto done;
1428 	}
1429 
1430 	dd_dev_info(dd, "%s: per-lane errors: 0x%x\n", __func__, reg32);
1431 
1432 	/* extract status, look for our HFI */
1433 	status = (reg >> ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_STS_SHIFT)
1434 			& ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_STS_MASK;
1435 	if ((status & (1 << dd->hfi1_id)) == 0) {
1436 		dd_dev_err(dd,
1437 			   "%s: gasket status 0x%x, expecting 0x%x\n",
1438 			   __func__, status, 1 << dd->hfi1_id);
1439 		ret = -EIO;
1440 		goto done;
1441 	}
1442 
1443 	/* extract error */
1444 	err = (reg >> ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_ERR_SHIFT)
1445 		& ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_ERR_MASK;
1446 	if (err) {
1447 		dd_dev_err(dd, "%s: gasket error %d\n", __func__, err);
1448 		ret = -EIO;
1449 		goto done;
1450 	}
1451 
1452 	/* update our link information cache */
1453 	update_lbus_info(dd);
1454 	dd_dev_info(dd, "%s: new speed and width: %s\n", __func__,
1455 		    dd->lbus_info);
1456 
1457 	if (dd->lbus_speed != target_speed) { /* not target */
1458 		/* maybe retry */
1459 		do_retry = retry_count < pcie_retry;
1460 		dd_dev_err(dd, "PCIe link speed did not switch to Gen%d%s\n",
1461 			   pcie_target, do_retry ? ", retrying" : "");
1462 		retry_count++;
1463 		if (do_retry) {
1464 			msleep(100); /* allow time to settle */
1465 			goto retry;
1466 		}
1467 		ret = -EIO;
1468 	}
1469 
1470 done:
1471 	if (therm) {
1472 		write_csr(dd, ASIC_CFG_THERM_POLL_EN, 0x1);
1473 		msleep(100);
1474 		dd_dev_info(dd, "%s: Re-enable therm polling\n",
1475 			    __func__);
1476 	}
1477 	release_chip_resource(dd, CR_SBUS);
1478 done_no_mutex:
1479 	/* return no error if it is OK to be at current speed */
1480 	if (ret && !return_error) {
1481 		dd_dev_err(dd, "Proceeding at current speed PCIe speed\n");
1482 		ret = 0;
1483 	}
1484 
1485 	dd_dev_info(dd, "%s: done\n", __func__);
1486 	return ret;
1487 }
1488