xref: /freebsd/sys/dev/ioat/ioat.c (revision 716fd348e01c5f2ba125f878a634a753436c2994)
1 /*-
2  * Copyright (C) 2012 Intel Corporation
3  * All rights reserved.
4  * Copyright (C) 2018 Alexander Motin <mav@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include "opt_ddb.h"
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/bus.h>
36 #include <sys/conf.h>
37 #include <sys/domainset.h>
38 #include <sys/fail.h>
39 #include <sys/ioccom.h>
40 #include <sys/kernel.h>
41 #include <sys/ktr.h>
42 #include <sys/lock.h>
43 #include <sys/malloc.h>
44 #include <sys/module.h>
45 #include <sys/mutex.h>
46 #include <sys/rman.h>
47 #include <sys/sbuf.h>
48 #include <sys/smp.h>
49 #include <sys/sysctl.h>
50 #include <sys/taskqueue.h>
51 #include <sys/time.h>
52 #include <dev/pci/pcireg.h>
53 #include <dev/pci/pcivar.h>
54 #include <machine/bus.h>
55 #include <machine/resource.h>
56 #include <machine/stdarg.h>
57 
58 #ifdef DDB
59 #include <ddb/ddb.h>
60 #endif
61 
62 #include "ioat.h"
63 #include "ioat_hw.h"
64 #include "ioat_internal.h"
65 
66 #ifndef	BUS_SPACE_MAXADDR_40BIT
67 #define	BUS_SPACE_MAXADDR_40BIT	MIN(BUS_SPACE_MAXADDR, 0xFFFFFFFFFFULL)
68 #endif
69 #ifndef	BUS_SPACE_MAXADDR_46BIT
70 #define	BUS_SPACE_MAXADDR_46BIT	MIN(BUS_SPACE_MAXADDR, 0x3FFFFFFFFFFFULL)
71 #endif
72 
73 static int ioat_modevent(module_t mod, int type, void *data);
74 static int ioat_probe(device_t device);
75 static int ioat_attach(device_t device);
76 static int ioat_detach(device_t device);
77 static int ioat_setup_intr(struct ioat_softc *ioat);
78 static int ioat_teardown_intr(struct ioat_softc *ioat);
79 static int ioat3_attach(device_t device);
80 static int ioat_start_channel(struct ioat_softc *ioat);
81 static int ioat_map_pci_bar(struct ioat_softc *ioat);
82 static void ioat_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nseg,
83     int error);
84 static void ioat_interrupt_handler(void *arg);
85 static boolean_t ioat_model_resets_msix(struct ioat_softc *ioat);
86 static int chanerr_to_errno(uint32_t);
87 static void ioat_process_events(struct ioat_softc *ioat, boolean_t intr);
88 static inline uint32_t ioat_get_active(struct ioat_softc *ioat);
89 static inline uint32_t ioat_get_ring_space(struct ioat_softc *ioat);
90 static void ioat_free_ring(struct ioat_softc *, uint32_t size,
91     struct ioat_descriptor *);
92 static int ioat_reserve_space(struct ioat_softc *, uint32_t, int mflags);
93 static union ioat_hw_descriptor *ioat_get_descriptor(struct ioat_softc *,
94     uint32_t index);
95 static struct ioat_descriptor *ioat_get_ring_entry(struct ioat_softc *,
96     uint32_t index);
97 static void ioat_halted_debug(struct ioat_softc *, uint32_t);
98 static void ioat_poll_timer_callback(void *arg);
99 static void dump_descriptor(void *hw_desc);
100 static void ioat_submit_single(struct ioat_softc *ioat);
101 static void ioat_comp_update_map(void *arg, bus_dma_segment_t *seg, int nseg,
102     int error);
103 static int ioat_reset_hw(struct ioat_softc *ioat);
104 static void ioat_reset_hw_task(void *, int);
105 static void ioat_setup_sysctl(device_t device);
106 static int sysctl_handle_reset(SYSCTL_HANDLER_ARGS);
107 static void ioat_get(struct ioat_softc *);
108 static void ioat_put(struct ioat_softc *);
109 static void ioat_drain_locked(struct ioat_softc *);
110 
111 #define	ioat_log_message(v, ...) do {					\
112 	if ((v) <= g_ioat_debug_level) {				\
113 		device_printf(ioat->device, __VA_ARGS__);		\
114 	}								\
115 } while (0)
116 
117 MALLOC_DEFINE(M_IOAT, "ioat", "ioat driver memory allocations");
118 SYSCTL_NODE(_hw, OID_AUTO, ioat, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
119     "ioat node");
120 
121 static int g_force_legacy_interrupts;
122 SYSCTL_INT(_hw_ioat, OID_AUTO, force_legacy_interrupts, CTLFLAG_RDTUN,
123     &g_force_legacy_interrupts, 0, "Set to non-zero to force MSI-X disabled");
124 
125 int g_ioat_debug_level = 0;
126 SYSCTL_INT(_hw_ioat, OID_AUTO, debug_level, CTLFLAG_RWTUN, &g_ioat_debug_level,
127     0, "Set log level (0-3) for ioat(4). Higher is more verbose.");
128 
129 unsigned g_ioat_ring_order = 13;
130 SYSCTL_UINT(_hw_ioat, OID_AUTO, ring_order, CTLFLAG_RDTUN, &g_ioat_ring_order,
131     0, "Set IOAT ring order.  (1 << this) == ring size.");
132 
133 /*
134  * OS <-> Driver interface structures
135  */
136 static device_method_t ioat_pci_methods[] = {
137 	/* Device interface */
138 	DEVMETHOD(device_probe,     ioat_probe),
139 	DEVMETHOD(device_attach,    ioat_attach),
140 	DEVMETHOD(device_detach,    ioat_detach),
141 	DEVMETHOD_END
142 };
143 
144 static driver_t ioat_pci_driver = {
145 	"ioat",
146 	ioat_pci_methods,
147 	sizeof(struct ioat_softc),
148 };
149 
150 DRIVER_MODULE(ioat, pci, ioat_pci_driver, ioat_modevent, NULL);
151 MODULE_VERSION(ioat, 1);
152 
153 /*
154  * Private data structures
155  */
156 static struct ioat_softc *ioat_channel[IOAT_MAX_CHANNELS];
157 static unsigned ioat_channel_index = 0;
158 SYSCTL_UINT(_hw_ioat, OID_AUTO, channels, CTLFLAG_RD, &ioat_channel_index, 0,
159     "Number of IOAT channels attached");
160 static struct mtx ioat_list_mtx;
161 MTX_SYSINIT(ioat_list_mtx, &ioat_list_mtx, "ioat list mtx", MTX_DEF);
162 
163 static struct _pcsid
164 {
165 	u_int32_t   type;
166 	const char  *desc;
167 } pci_ids[] = {
168 	{ 0x34308086, "TBG IOAT Ch0" },
169 	{ 0x34318086, "TBG IOAT Ch1" },
170 	{ 0x34328086, "TBG IOAT Ch2" },
171 	{ 0x34338086, "TBG IOAT Ch3" },
172 	{ 0x34298086, "TBG IOAT Ch4" },
173 	{ 0x342a8086, "TBG IOAT Ch5" },
174 	{ 0x342b8086, "TBG IOAT Ch6" },
175 	{ 0x342c8086, "TBG IOAT Ch7" },
176 
177 	{ 0x37108086, "JSF IOAT Ch0" },
178 	{ 0x37118086, "JSF IOAT Ch1" },
179 	{ 0x37128086, "JSF IOAT Ch2" },
180 	{ 0x37138086, "JSF IOAT Ch3" },
181 	{ 0x37148086, "JSF IOAT Ch4" },
182 	{ 0x37158086, "JSF IOAT Ch5" },
183 	{ 0x37168086, "JSF IOAT Ch6" },
184 	{ 0x37178086, "JSF IOAT Ch7" },
185 	{ 0x37188086, "JSF IOAT Ch0 (RAID)" },
186 	{ 0x37198086, "JSF IOAT Ch1 (RAID)" },
187 
188 	{ 0x3c208086, "SNB IOAT Ch0" },
189 	{ 0x3c218086, "SNB IOAT Ch1" },
190 	{ 0x3c228086, "SNB IOAT Ch2" },
191 	{ 0x3c238086, "SNB IOAT Ch3" },
192 	{ 0x3c248086, "SNB IOAT Ch4" },
193 	{ 0x3c258086, "SNB IOAT Ch5" },
194 	{ 0x3c268086, "SNB IOAT Ch6" },
195 	{ 0x3c278086, "SNB IOAT Ch7" },
196 	{ 0x3c2e8086, "SNB IOAT Ch0 (RAID)" },
197 	{ 0x3c2f8086, "SNB IOAT Ch1 (RAID)" },
198 
199 	{ 0x0e208086, "IVB IOAT Ch0" },
200 	{ 0x0e218086, "IVB IOAT Ch1" },
201 	{ 0x0e228086, "IVB IOAT Ch2" },
202 	{ 0x0e238086, "IVB IOAT Ch3" },
203 	{ 0x0e248086, "IVB IOAT Ch4" },
204 	{ 0x0e258086, "IVB IOAT Ch5" },
205 	{ 0x0e268086, "IVB IOAT Ch6" },
206 	{ 0x0e278086, "IVB IOAT Ch7" },
207 	{ 0x0e2e8086, "IVB IOAT Ch0 (RAID)" },
208 	{ 0x0e2f8086, "IVB IOAT Ch1 (RAID)" },
209 
210 	{ 0x2f208086, "HSW IOAT Ch0" },
211 	{ 0x2f218086, "HSW IOAT Ch1" },
212 	{ 0x2f228086, "HSW IOAT Ch2" },
213 	{ 0x2f238086, "HSW IOAT Ch3" },
214 	{ 0x2f248086, "HSW IOAT Ch4" },
215 	{ 0x2f258086, "HSW IOAT Ch5" },
216 	{ 0x2f268086, "HSW IOAT Ch6" },
217 	{ 0x2f278086, "HSW IOAT Ch7" },
218 	{ 0x2f2e8086, "HSW IOAT Ch0 (RAID)" },
219 	{ 0x2f2f8086, "HSW IOAT Ch1 (RAID)" },
220 
221 	{ 0x0c508086, "BWD IOAT Ch0" },
222 	{ 0x0c518086, "BWD IOAT Ch1" },
223 	{ 0x0c528086, "BWD IOAT Ch2" },
224 	{ 0x0c538086, "BWD IOAT Ch3" },
225 
226 	{ 0x6f508086, "BDXDE IOAT Ch0" },
227 	{ 0x6f518086, "BDXDE IOAT Ch1" },
228 	{ 0x6f528086, "BDXDE IOAT Ch2" },
229 	{ 0x6f538086, "BDXDE IOAT Ch3" },
230 
231 	{ 0x6f208086, "BDX IOAT Ch0" },
232 	{ 0x6f218086, "BDX IOAT Ch1" },
233 	{ 0x6f228086, "BDX IOAT Ch2" },
234 	{ 0x6f238086, "BDX IOAT Ch3" },
235 	{ 0x6f248086, "BDX IOAT Ch4" },
236 	{ 0x6f258086, "BDX IOAT Ch5" },
237 	{ 0x6f268086, "BDX IOAT Ch6" },
238 	{ 0x6f278086, "BDX IOAT Ch7" },
239 	{ 0x6f2e8086, "BDX IOAT Ch0 (RAID)" },
240 	{ 0x6f2f8086, "BDX IOAT Ch1 (RAID)" },
241 
242 	{ 0x20218086, "SKX IOAT" },
243 };
244 
245 MODULE_PNP_INFO("W32:vendor/device;D:#", pci, ioat, pci_ids,
246     nitems(pci_ids));
247 
248 /*
249  * OS <-> Driver linkage functions
250  */
251 static int
252 ioat_modevent(module_t mod __unused, int type, void *data __unused)
253 {
254 	switch(type) {
255 	case MOD_LOAD:
256 		break;
257 
258 	case MOD_UNLOAD:
259 		ioat_test_detach();
260 		break;
261 
262 	case MOD_SHUTDOWN:
263 		break;
264 
265 	default:
266 		return (EOPNOTSUPP);
267 	}
268 
269 	return (0);
270 }
271 
272 static int
273 ioat_probe(device_t device)
274 {
275 	struct _pcsid *ep;
276 	u_int32_t type;
277 
278 	type = pci_get_devid(device);
279 	for (ep = pci_ids; ep < &pci_ids[nitems(pci_ids)]; ep++) {
280 		if (ep->type == type) {
281 			device_set_desc(device, ep->desc);
282 			return (0);
283 		}
284 	}
285 	return (ENXIO);
286 }
287 
288 static int
289 ioat_attach(device_t device)
290 {
291 	struct ioat_softc *ioat;
292 	int error, i;
293 
294 	ioat = DEVICE2SOFTC(device);
295 	ioat->device = device;
296 	if (bus_get_domain(device, &ioat->domain) != 0)
297 		ioat->domain = 0;
298 	ioat->cpu = CPU_FFS(&cpuset_domain[ioat->domain]) - 1;
299 	if (ioat->cpu < 0)
300 		ioat->cpu = CPU_FIRST();
301 
302 	error = ioat_map_pci_bar(ioat);
303 	if (error != 0)
304 		goto err;
305 
306 	ioat->version = ioat_read_cbver(ioat);
307 	if (ioat->version < IOAT_VER_3_0) {
308 		error = ENODEV;
309 		goto err;
310 	}
311 
312 	error = ioat3_attach(device);
313 	if (error != 0)
314 		goto err;
315 
316 	error = pci_enable_busmaster(device);
317 	if (error != 0)
318 		goto err;
319 
320 	error = ioat_setup_intr(ioat);
321 	if (error != 0)
322 		goto err;
323 
324 	error = ioat_reset_hw(ioat);
325 	if (error != 0)
326 		goto err;
327 
328 	ioat_process_events(ioat, FALSE);
329 	ioat_setup_sysctl(device);
330 
331 	mtx_lock(&ioat_list_mtx);
332 	for (i = 0; i < IOAT_MAX_CHANNELS; i++) {
333 		if (ioat_channel[i] == NULL)
334 			break;
335 	}
336 	if (i >= IOAT_MAX_CHANNELS) {
337 		mtx_unlock(&ioat_list_mtx);
338 		device_printf(device, "Too many I/OAT devices in system\n");
339 		error = ENXIO;
340 		goto err;
341 	}
342 	ioat->chan_idx = i;
343 	ioat_channel[i] = ioat;
344 	if (i >= ioat_channel_index)
345 		ioat_channel_index = i + 1;
346 	mtx_unlock(&ioat_list_mtx);
347 
348 	ioat_test_attach();
349 
350 err:
351 	if (error != 0)
352 		ioat_detach(device);
353 	return (error);
354 }
355 
356 static inline int
357 ioat_bus_dmamap_destroy(struct ioat_softc *ioat, const char *func,
358     bus_dma_tag_t dmat, bus_dmamap_t map)
359 {
360 	int error;
361 
362 	error = bus_dmamap_destroy(dmat, map);
363 	if (error != 0) {
364 		ioat_log_message(0,
365 		    "%s: bus_dmamap_destroy failed %d\n", func, error);
366 	}
367 
368 	return (error);
369 }
370 
371 static int
372 ioat_detach(device_t device)
373 {
374 	struct ioat_softc *ioat;
375 	int i, error;
376 
377 	ioat = DEVICE2SOFTC(device);
378 
379 	mtx_lock(&ioat_list_mtx);
380 	ioat_channel[ioat->chan_idx] = NULL;
381 	while (ioat_channel_index > 0 &&
382 	    ioat_channel[ioat_channel_index - 1] == NULL)
383 		ioat_channel_index--;
384 	mtx_unlock(&ioat_list_mtx);
385 
386 	taskqueue_drain(taskqueue_thread, &ioat->reset_task);
387 
388 	mtx_lock(&ioat->submit_lock);
389 	ioat->quiescing = TRUE;
390 	ioat->destroying = TRUE;
391 	wakeup(&ioat->quiescing);
392 	wakeup(&ioat->resetting);
393 
394 	ioat_drain_locked(ioat);
395 	mtx_unlock(&ioat->submit_lock);
396 	mtx_lock(&ioat->cleanup_lock);
397 	while (ioat_get_active(ioat) > 0)
398 		msleep(&ioat->tail, &ioat->cleanup_lock, 0, "ioat_drain", 1);
399 	mtx_unlock(&ioat->cleanup_lock);
400 
401 	ioat_teardown_intr(ioat);
402 	callout_drain(&ioat->poll_timer);
403 
404 	pci_disable_busmaster(device);
405 
406 	if (ioat->pci_resource != NULL)
407 		bus_release_resource(device, SYS_RES_MEMORY,
408 		    ioat->pci_resource_id, ioat->pci_resource);
409 
410 	if (ioat->data_tag != NULL) {
411 		for (i = 0; i < 1 << ioat->ring_size_order; i++) {
412 			error = ioat_bus_dmamap_destroy(ioat, __func__,
413 			    ioat->data_tag, ioat->ring[i].src_dmamap);
414 			if (error != 0)
415 				return (error);
416 		}
417 		for (i = 0; i < 1 << ioat->ring_size_order; i++) {
418 			error = ioat_bus_dmamap_destroy(ioat, __func__,
419 			    ioat->data_tag, ioat->ring[i].dst_dmamap);
420 			if (error != 0)
421 				return (error);
422 		}
423 
424 		for (i = 0; i < 1 << ioat->ring_size_order; i++) {
425 			error = ioat_bus_dmamap_destroy(ioat, __func__,
426 			    ioat->data_tag, ioat->ring[i].src2_dmamap);
427 			if (error != 0)
428 				return (error);
429 		}
430 		for (i = 0; i < 1 << ioat->ring_size_order; i++) {
431 			error = ioat_bus_dmamap_destroy(ioat, __func__,
432 			    ioat->data_tag, ioat->ring[i].dst2_dmamap);
433 			if (error != 0)
434 				return (error);
435 		}
436 
437 		bus_dma_tag_destroy(ioat->data_tag);
438 	}
439 
440 	if (ioat->ring != NULL)
441 		ioat_free_ring(ioat, 1 << ioat->ring_size_order, ioat->ring);
442 
443 	if (ioat->comp_update != NULL) {
444 		bus_dmamap_unload(ioat->comp_update_tag, ioat->comp_update_map);
445 		bus_dmamem_free(ioat->comp_update_tag, ioat->comp_update,
446 		    ioat->comp_update_map);
447 		bus_dma_tag_destroy(ioat->comp_update_tag);
448 	}
449 
450 	if (ioat->hw_desc_ring != NULL) {
451 		bus_dmamap_unload(ioat->hw_desc_tag, ioat->hw_desc_map);
452 		bus_dmamem_free(ioat->hw_desc_tag, ioat->hw_desc_ring,
453 		    ioat->hw_desc_map);
454 		bus_dma_tag_destroy(ioat->hw_desc_tag);
455 	}
456 
457 	return (0);
458 }
459 
460 static int
461 ioat_teardown_intr(struct ioat_softc *ioat)
462 {
463 
464 	if (ioat->tag != NULL)
465 		bus_teardown_intr(ioat->device, ioat->res, ioat->tag);
466 
467 	if (ioat->res != NULL)
468 		bus_release_resource(ioat->device, SYS_RES_IRQ,
469 		    rman_get_rid(ioat->res), ioat->res);
470 
471 	pci_release_msi(ioat->device);
472 	return (0);
473 }
474 
475 static int
476 ioat_start_channel(struct ioat_softc *ioat)
477 {
478 	struct ioat_dma_hw_descriptor *hw_desc;
479 	struct ioat_descriptor *desc;
480 	struct bus_dmadesc *dmadesc;
481 	uint64_t status;
482 	uint32_t chanerr;
483 	int i;
484 
485 	ioat_acquire(&ioat->dmaengine);
486 
487 	/* Submit 'NULL' operation manually to avoid quiescing flag */
488 	desc = ioat_get_ring_entry(ioat, ioat->head);
489 	hw_desc = &ioat_get_descriptor(ioat, ioat->head)->dma;
490 	dmadesc = &desc->bus_dmadesc;
491 
492 	dmadesc->callback_fn = NULL;
493 	dmadesc->callback_arg = NULL;
494 
495 	hw_desc->u.control_raw = 0;
496 	hw_desc->u.control_generic.op = IOAT_OP_COPY;
497 	hw_desc->u.control_generic.completion_update = 1;
498 	hw_desc->size = 8;
499 	hw_desc->src_addr = 0;
500 	hw_desc->dest_addr = 0;
501 	hw_desc->u.control.null = 1;
502 
503 	ioat_submit_single(ioat);
504 	ioat_release(&ioat->dmaengine);
505 
506 	for (i = 0; i < 100; i++) {
507 		DELAY(1);
508 		status = ioat_get_chansts(ioat);
509 		if (is_ioat_idle(status))
510 			return (0);
511 	}
512 
513 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
514 	ioat_log_message(0, "could not start channel: "
515 	    "status = %#jx error = %b\n", (uintmax_t)status, (int)chanerr,
516 	    IOAT_CHANERR_STR);
517 	return (ENXIO);
518 }
519 
520 /*
521  * Initialize Hardware
522  */
523 static int
524 ioat3_attach(device_t device)
525 {
526 	struct ioat_softc *ioat;
527 	struct ioat_descriptor *ring;
528 	struct ioat_dma_hw_descriptor *dma_hw_desc;
529 	void *hw_desc;
530 	bus_addr_t lowaddr;
531 	size_t ringsz;
532 	int i, num_descriptors;
533 	int error;
534 	uint8_t xfercap;
535 
536 	error = 0;
537 	ioat = DEVICE2SOFTC(device);
538 	ioat->capabilities = ioat_read_dmacapability(ioat);
539 
540 	ioat_log_message(0, "Capabilities: %b\n", (int)ioat->capabilities,
541 	    IOAT_DMACAP_STR);
542 
543 	xfercap = ioat_read_xfercap(ioat);
544 	ioat->max_xfer_size = 1 << xfercap;
545 
546 	ioat->intrdelay_supported = (ioat_read_2(ioat, IOAT_INTRDELAY_OFFSET) &
547 	    IOAT_INTRDELAY_SUPPORTED) != 0;
548 	if (ioat->intrdelay_supported)
549 		ioat->intrdelay_max = IOAT_INTRDELAY_US_MASK;
550 
551 	/* TODO: need to check DCA here if we ever do XOR/PQ */
552 
553 	mtx_init(&ioat->submit_lock, "ioat_submit", NULL, MTX_DEF);
554 	mtx_init(&ioat->cleanup_lock, "ioat_cleanup", NULL, MTX_DEF);
555 	callout_init(&ioat->poll_timer, 1);
556 	TASK_INIT(&ioat->reset_task, 0, ioat_reset_hw_task, ioat);
557 
558 	/* Establish lock order for Witness */
559 	mtx_lock(&ioat->cleanup_lock);
560 	mtx_lock(&ioat->submit_lock);
561 	mtx_unlock(&ioat->submit_lock);
562 	mtx_unlock(&ioat->cleanup_lock);
563 
564 	ioat->is_submitter_processing = FALSE;
565 
566 	if (ioat->version >= IOAT_VER_3_3)
567 		lowaddr = BUS_SPACE_MAXADDR_48BIT;
568 	else if (ioat->version >= IOAT_VER_3_2)
569 		lowaddr = BUS_SPACE_MAXADDR_46BIT;
570 	else
571 		lowaddr = BUS_SPACE_MAXADDR_40BIT;
572 
573 	error = bus_dma_tag_create(bus_get_dma_tag(ioat->device),
574 	    sizeof(uint64_t), 0x0, lowaddr, BUS_SPACE_MAXADDR, NULL, NULL,
575 	    sizeof(uint64_t), 1, sizeof(uint64_t), 0, NULL, NULL,
576 	    &ioat->comp_update_tag);
577 	if (error != 0)
578 		return (error);
579 
580 	error = bus_dmamem_alloc(ioat->comp_update_tag,
581 	    (void **)&ioat->comp_update, BUS_DMA_ZERO | BUS_DMA_WAITOK,
582 	    &ioat->comp_update_map);
583 	if (error != 0)
584 		return (error);
585 
586 	error = bus_dmamap_load(ioat->comp_update_tag, ioat->comp_update_map,
587 	    ioat->comp_update, sizeof(uint64_t), ioat_comp_update_map, ioat,
588 	    BUS_DMA_NOWAIT);
589 	if (error != 0)
590 		return (error);
591 
592 	ioat->ring_size_order = g_ioat_ring_order;
593 	num_descriptors = 1 << ioat->ring_size_order;
594 	ringsz = sizeof(struct ioat_dma_hw_descriptor) * num_descriptors;
595 
596 	error = bus_dma_tag_create(bus_get_dma_tag(ioat->device),
597 	    2 * 1024 * 1024, 0x0, lowaddr, BUS_SPACE_MAXADDR, NULL, NULL,
598 	    ringsz, 1, ringsz, 0, NULL, NULL, &ioat->hw_desc_tag);
599 	if (error != 0)
600 		return (error);
601 
602 	error = bus_dmamem_alloc(ioat->hw_desc_tag, &hw_desc,
603 	    BUS_DMA_ZERO | BUS_DMA_WAITOK, &ioat->hw_desc_map);
604 	if (error != 0)
605 		return (error);
606 
607 	error = bus_dmamap_load(ioat->hw_desc_tag, ioat->hw_desc_map, hw_desc,
608 	    ringsz, ioat_dmamap_cb, &ioat->hw_desc_bus_addr, BUS_DMA_NOWAIT);
609 	if (error)
610 		return (error);
611 
612 	ioat->hw_desc_ring = hw_desc;
613 
614 	error = bus_dma_tag_create(bus_get_dma_tag(ioat->device),
615 	    1, 0, lowaddr, BUS_SPACE_MAXADDR, NULL, NULL,
616 	    ioat->max_xfer_size, 1, ioat->max_xfer_size, 0, NULL, NULL,
617 	    &ioat->data_tag);
618 	if (error != 0)
619 		return (error);
620 	ioat->ring = malloc_domainset(num_descriptors * sizeof(*ring), M_IOAT,
621 	    DOMAINSET_PREF(ioat->domain), M_ZERO | M_WAITOK);
622 
623 	ring = ioat->ring;
624 	for (i = 0; i < num_descriptors; i++) {
625 		memset(&ring[i].bus_dmadesc, 0, sizeof(ring[i].bus_dmadesc));
626 		ring[i].id = i;
627 		error = bus_dmamap_create(ioat->data_tag, 0,
628                     &ring[i].src_dmamap);
629 		if (error != 0) {
630 			ioat_log_message(0,
631 			    "%s: bus_dmamap_create failed %d\n", __func__,
632 			    error);
633 			return (error);
634 		}
635 		error = bus_dmamap_create(ioat->data_tag, 0,
636                     &ring[i].dst_dmamap);
637 		if (error != 0) {
638 			ioat_log_message(0,
639 			    "%s: bus_dmamap_create failed %d\n", __func__,
640 			    error);
641 			return (error);
642 		}
643 		error = bus_dmamap_create(ioat->data_tag, 0,
644                     &ring[i].src2_dmamap);
645 		if (error != 0) {
646 			ioat_log_message(0,
647 			    "%s: bus_dmamap_create failed %d\n", __func__,
648 			    error);
649 			return (error);
650 		}
651 		error = bus_dmamap_create(ioat->data_tag, 0,
652                     &ring[i].dst2_dmamap);
653 		if (error != 0) {
654 			ioat_log_message(0,
655 			    "%s: bus_dmamap_create failed %d\n", __func__,
656 			    error);
657 			return (error);
658 		}
659 	}
660 
661 	for (i = 0; i < num_descriptors; i++) {
662 		dma_hw_desc = &ioat->hw_desc_ring[i].dma;
663 		dma_hw_desc->next = RING_PHYS_ADDR(ioat, i + 1);
664 	}
665 
666 	ioat->tail = ioat->head = 0;
667 	*ioat->comp_update = ioat->last_seen =
668 	    RING_PHYS_ADDR(ioat, ioat->tail - 1);
669 	return (0);
670 }
671 
672 static int
673 ioat_map_pci_bar(struct ioat_softc *ioat)
674 {
675 
676 	ioat->pci_resource_id = PCIR_BAR(0);
677 	ioat->pci_resource = bus_alloc_resource_any(ioat->device,
678 	    SYS_RES_MEMORY, &ioat->pci_resource_id, RF_ACTIVE);
679 
680 	if (ioat->pci_resource == NULL) {
681 		ioat_log_message(0, "unable to allocate pci resource\n");
682 		return (ENODEV);
683 	}
684 
685 	ioat->pci_bus_tag = rman_get_bustag(ioat->pci_resource);
686 	ioat->pci_bus_handle = rman_get_bushandle(ioat->pci_resource);
687 	return (0);
688 }
689 
690 static void
691 ioat_comp_update_map(void *arg, bus_dma_segment_t *seg, int nseg, int error)
692 {
693 	struct ioat_softc *ioat = arg;
694 
695 	KASSERT(error == 0, ("%s: error:%d", __func__, error));
696 	ioat->comp_update_bus_addr = seg[0].ds_addr;
697 }
698 
699 static void
700 ioat_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nseg, int error)
701 {
702 	bus_addr_t *baddr;
703 
704 	KASSERT(error == 0, ("%s: error:%d", __func__, error));
705 	baddr = arg;
706 	*baddr = segs->ds_addr;
707 }
708 
709 /*
710  * Interrupt setup and handlers
711  */
712 static int
713 ioat_setup_intr(struct ioat_softc *ioat)
714 {
715 	uint32_t num_vectors;
716 	int error;
717 	boolean_t use_msix;
718 
719 	use_msix = FALSE;
720 
721 	if (!g_force_legacy_interrupts && pci_msix_count(ioat->device) >= 1) {
722 		num_vectors = 1;
723 		pci_alloc_msix(ioat->device, &num_vectors);
724 		if (num_vectors == 1)
725 			use_msix = TRUE;
726 	}
727 
728 	if (use_msix) {
729 		ioat->rid = 1;
730 		ioat->res = bus_alloc_resource_any(ioat->device, SYS_RES_IRQ,
731 		    &ioat->rid, RF_ACTIVE);
732 	} else {
733 		ioat->rid = 0;
734 		ioat->res = bus_alloc_resource_any(ioat->device, SYS_RES_IRQ,
735 		    &ioat->rid, RF_SHAREABLE | RF_ACTIVE);
736 	}
737 	if (ioat->res == NULL) {
738 		ioat_log_message(0, "bus_alloc_resource failed\n");
739 		return (ENOMEM);
740 	}
741 
742 	ioat->tag = NULL;
743 	error = bus_setup_intr(ioat->device, ioat->res, INTR_MPSAFE |
744 	    INTR_TYPE_MISC, NULL, ioat_interrupt_handler, ioat, &ioat->tag);
745 	if (error != 0) {
746 		ioat_log_message(0, "bus_setup_intr failed\n");
747 		return (error);
748 	}
749 
750 	ioat_write_intrctrl(ioat, IOAT_INTRCTRL_MASTER_INT_EN);
751 	return (0);
752 }
753 
754 static boolean_t
755 ioat_model_resets_msix(struct ioat_softc *ioat)
756 {
757 	u_int32_t pciid;
758 
759 	pciid = pci_get_devid(ioat->device);
760 	switch (pciid) {
761 		/* BWD: */
762 	case 0x0c508086:
763 	case 0x0c518086:
764 	case 0x0c528086:
765 	case 0x0c538086:
766 		/* BDXDE: */
767 	case 0x6f508086:
768 	case 0x6f518086:
769 	case 0x6f528086:
770 	case 0x6f538086:
771 		return (TRUE);
772 	}
773 
774 	return (FALSE);
775 }
776 
777 static void
778 ioat_interrupt_handler(void *arg)
779 {
780 	struct ioat_softc *ioat = arg;
781 
782 	ioat->stats.interrupts++;
783 	ioat_process_events(ioat, TRUE);
784 }
785 
786 static int
787 chanerr_to_errno(uint32_t chanerr)
788 {
789 
790 	if (chanerr == 0)
791 		return (0);
792 	if ((chanerr & (IOAT_CHANERR_XSADDERR | IOAT_CHANERR_XDADDERR)) != 0)
793 		return (EFAULT);
794 	if ((chanerr & (IOAT_CHANERR_RDERR | IOAT_CHANERR_WDERR)) != 0)
795 		return (EIO);
796 	/* This one is probably our fault: */
797 	if ((chanerr & IOAT_CHANERR_NDADDERR) != 0)
798 		return (EIO);
799 	return (EIO);
800 }
801 
802 static void
803 ioat_process_events(struct ioat_softc *ioat, boolean_t intr)
804 {
805 	struct ioat_descriptor *desc;
806 	struct bus_dmadesc *dmadesc;
807 	uint64_t comp_update, status;
808 	uint32_t completed, chanerr;
809 	int error __diagused;
810 
811 	if (intr) {
812 		mtx_lock(&ioat->cleanup_lock);
813 	} else {
814 		if (!mtx_trylock(&ioat->cleanup_lock))
815 			return;
816 	}
817 
818 	/*
819 	 * Don't run while the hardware is being reset.  Reset is responsible
820 	 * for blocking new work and draining & completing existing work, so
821 	 * there is nothing to do until new work is queued after reset anyway.
822 	 */
823 	if (ioat->resetting_cleanup) {
824 		mtx_unlock(&ioat->cleanup_lock);
825 		return;
826 	}
827 
828 	completed = 0;
829 	comp_update = *ioat->comp_update;
830 	status = comp_update & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_MASK;
831 
832 	if (status < ioat->hw_desc_bus_addr ||
833 	    status >= ioat->hw_desc_bus_addr + (1 << ioat->ring_size_order) *
834 	    sizeof(struct ioat_generic_hw_descriptor))
835 		panic("Bogus completion address %jx (channel %u)",
836 		    (uintmax_t)status, ioat->chan_idx);
837 
838 	if (status == ioat->last_seen) {
839 		/*
840 		 * If we landed in process_events and nothing has been
841 		 * completed, check for a timeout due to channel halt.
842 		 */
843 		goto out;
844 	}
845 	CTR4(KTR_IOAT, "%s channel=%u hw_status=0x%lx last_seen=0x%lx",
846 	    __func__, ioat->chan_idx, comp_update, ioat->last_seen);
847 
848 	while (RING_PHYS_ADDR(ioat, ioat->tail - 1) != status) {
849 		desc = ioat_get_ring_entry(ioat, ioat->tail);
850 		dmadesc = &desc->bus_dmadesc;
851 		CTR5(KTR_IOAT, "channel=%u completing desc idx %u (%p) ok  cb %p(%p)",
852 		    ioat->chan_idx, ioat->tail, dmadesc, dmadesc->callback_fn,
853 		    dmadesc->callback_arg);
854 
855 		bus_dmamap_unload(ioat->data_tag, desc->src_dmamap);
856 		bus_dmamap_unload(ioat->data_tag, desc->dst_dmamap);
857 		bus_dmamap_unload(ioat->data_tag, desc->src2_dmamap);
858 		bus_dmamap_unload(ioat->data_tag, desc->dst2_dmamap);
859 
860 		if (dmadesc->callback_fn != NULL)
861 			dmadesc->callback_fn(dmadesc->callback_arg, 0);
862 
863 		completed++;
864 		ioat->tail++;
865 	}
866 	CTR5(KTR_IOAT, "%s channel=%u head=%u tail=%u active=%u", __func__,
867 	    ioat->chan_idx, ioat->head, ioat->tail, ioat_get_active(ioat));
868 
869 	if (completed != 0) {
870 		ioat->last_seen = RING_PHYS_ADDR(ioat, ioat->tail - 1);
871 		ioat->stats.descriptors_processed += completed;
872 		wakeup(&ioat->tail);
873 	}
874 
875 out:
876 	ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
877 	mtx_unlock(&ioat->cleanup_lock);
878 
879 	/*
880 	 * The device doesn't seem to reliably push suspend/halt statuses to
881 	 * the channel completion memory address, so poll the device register
882 	 * here.  For performance reasons skip it on interrupts, do it only
883 	 * on much more rare polling events.
884 	 */
885 	if (!intr)
886 		comp_update = ioat_get_chansts(ioat) & IOAT_CHANSTS_STATUS;
887 	if (!is_ioat_halted(comp_update) && !is_ioat_suspended(comp_update))
888 		return;
889 
890 	ioat->stats.channel_halts++;
891 
892 	/*
893 	 * Fatal programming error on this DMA channel.  Flush any outstanding
894 	 * work with error status and restart the engine.
895 	 */
896 	mtx_lock(&ioat->submit_lock);
897 	ioat->quiescing = TRUE;
898 	mtx_unlock(&ioat->submit_lock);
899 
900 	/*
901 	 * This is safe to do here because the submit queue is quiesced.  We
902 	 * know that we will drain all outstanding events, so ioat_reset_hw
903 	 * can't deadlock. It is necessary to protect other ioat_process_event
904 	 * threads from racing ioat_reset_hw, reading an indeterminate hw
905 	 * state, and attempting to continue issuing completions.
906 	 */
907 	mtx_lock(&ioat->cleanup_lock);
908 	ioat->resetting_cleanup = TRUE;
909 
910 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
911 	if (1 <= g_ioat_debug_level)
912 		ioat_halted_debug(ioat, chanerr);
913 	ioat->stats.last_halt_chanerr = chanerr;
914 
915 	while (ioat_get_active(ioat) > 0) {
916 		desc = ioat_get_ring_entry(ioat, ioat->tail);
917 		dmadesc = &desc->bus_dmadesc;
918 		CTR5(KTR_IOAT, "channel=%u completing desc idx %u (%p) err cb %p(%p)",
919 		    ioat->chan_idx, ioat->tail, dmadesc, dmadesc->callback_fn,
920 		    dmadesc->callback_arg);
921 
922 		if (dmadesc->callback_fn != NULL)
923 			dmadesc->callback_fn(dmadesc->callback_arg,
924 			    chanerr_to_errno(chanerr));
925 
926 		ioat->tail++;
927 		ioat->stats.descriptors_processed++;
928 		ioat->stats.descriptors_error++;
929 	}
930 	CTR5(KTR_IOAT, "%s channel=%u head=%u tail=%u active=%u", __func__,
931 	    ioat->chan_idx, ioat->head, ioat->tail, ioat_get_active(ioat));
932 
933 	/* Clear error status */
934 	ioat_write_4(ioat, IOAT_CHANERR_OFFSET, chanerr);
935 
936 	mtx_unlock(&ioat->cleanup_lock);
937 
938 	ioat_log_message(0, "Resetting channel to recover from error\n");
939 	error = taskqueue_enqueue(taskqueue_thread, &ioat->reset_task);
940 	KASSERT(error == 0,
941 	    ("%s: taskqueue_enqueue failed: %d", __func__, error));
942 }
943 
944 static void
945 ioat_reset_hw_task(void *ctx, int pending __unused)
946 {
947 	struct ioat_softc *ioat;
948 	int error __diagused;
949 
950 	ioat = ctx;
951 	ioat_log_message(1, "%s: Resetting channel\n", __func__);
952 
953 	error = ioat_reset_hw(ioat);
954 	KASSERT(error == 0, ("%s: reset failed: %d", __func__, error));
955 }
956 
957 /*
958  * User API functions
959  */
960 unsigned
961 ioat_get_nchannels(void)
962 {
963 
964 	return (ioat_channel_index);
965 }
966 
967 bus_dmaengine_t
968 ioat_get_dmaengine(uint32_t index, int flags)
969 {
970 	struct ioat_softc *ioat;
971 
972 	KASSERT((flags & ~(M_NOWAIT | M_WAITOK)) == 0,
973 	    ("invalid flags: 0x%08x", flags));
974 	KASSERT((flags & (M_NOWAIT | M_WAITOK)) != (M_NOWAIT | M_WAITOK),
975 	    ("invalid wait | nowait"));
976 
977 	mtx_lock(&ioat_list_mtx);
978 	if (index >= ioat_channel_index ||
979 	    (ioat = ioat_channel[index]) == NULL) {
980 		mtx_unlock(&ioat_list_mtx);
981 		return (NULL);
982 	}
983 	mtx_lock(&ioat->submit_lock);
984 	mtx_unlock(&ioat_list_mtx);
985 
986 	if (ioat->destroying) {
987 		mtx_unlock(&ioat->submit_lock);
988 		return (NULL);
989 	}
990 
991 	ioat_get(ioat);
992 	if (ioat->quiescing) {
993 		if ((flags & M_NOWAIT) != 0) {
994 			ioat_put(ioat);
995 			mtx_unlock(&ioat->submit_lock);
996 			return (NULL);
997 		}
998 
999 		while (ioat->quiescing && !ioat->destroying)
1000 			msleep(&ioat->quiescing, &ioat->submit_lock, 0, "getdma", 0);
1001 
1002 		if (ioat->destroying) {
1003 			ioat_put(ioat);
1004 			mtx_unlock(&ioat->submit_lock);
1005 			return (NULL);
1006 		}
1007 	}
1008 	mtx_unlock(&ioat->submit_lock);
1009 	return (&ioat->dmaengine);
1010 }
1011 
1012 void
1013 ioat_put_dmaengine(bus_dmaengine_t dmaengine)
1014 {
1015 	struct ioat_softc *ioat;
1016 
1017 	ioat = to_ioat_softc(dmaengine);
1018 	mtx_lock(&ioat->submit_lock);
1019 	ioat_put(ioat);
1020 	mtx_unlock(&ioat->submit_lock);
1021 }
1022 
1023 int
1024 ioat_get_hwversion(bus_dmaengine_t dmaengine)
1025 {
1026 	struct ioat_softc *ioat;
1027 
1028 	ioat = to_ioat_softc(dmaengine);
1029 	return (ioat->version);
1030 }
1031 
1032 size_t
1033 ioat_get_max_io_size(bus_dmaengine_t dmaengine)
1034 {
1035 	struct ioat_softc *ioat;
1036 
1037 	ioat = to_ioat_softc(dmaengine);
1038 	return (ioat->max_xfer_size);
1039 }
1040 
1041 uint32_t
1042 ioat_get_capabilities(bus_dmaengine_t dmaengine)
1043 {
1044 	struct ioat_softc *ioat;
1045 
1046 	ioat = to_ioat_softc(dmaengine);
1047 	return (ioat->capabilities);
1048 }
1049 
1050 int
1051 ioat_get_domain(bus_dmaengine_t dmaengine, int *domain)
1052 {
1053 	struct ioat_softc *ioat;
1054 
1055 	ioat = to_ioat_softc(dmaengine);
1056 	return (bus_get_domain(ioat->device, domain));
1057 }
1058 
1059 int
1060 ioat_set_interrupt_coalesce(bus_dmaengine_t dmaengine, uint16_t delay)
1061 {
1062 	struct ioat_softc *ioat;
1063 
1064 	ioat = to_ioat_softc(dmaengine);
1065 	if (!ioat->intrdelay_supported)
1066 		return (ENODEV);
1067 	if (delay > ioat->intrdelay_max)
1068 		return (ERANGE);
1069 
1070 	ioat_write_2(ioat, IOAT_INTRDELAY_OFFSET, delay);
1071 	ioat->cached_intrdelay =
1072 	    ioat_read_2(ioat, IOAT_INTRDELAY_OFFSET) & IOAT_INTRDELAY_US_MASK;
1073 	return (0);
1074 }
1075 
1076 uint16_t
1077 ioat_get_max_coalesce_period(bus_dmaengine_t dmaengine)
1078 {
1079 	struct ioat_softc *ioat;
1080 
1081 	ioat = to_ioat_softc(dmaengine);
1082 	return (ioat->intrdelay_max);
1083 }
1084 
1085 void
1086 ioat_acquire(bus_dmaengine_t dmaengine)
1087 {
1088 	struct ioat_softc *ioat;
1089 
1090 	ioat = to_ioat_softc(dmaengine);
1091 	mtx_lock(&ioat->submit_lock);
1092 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1093 	ioat->acq_head = ioat->head;
1094 }
1095 
1096 int
1097 ioat_acquire_reserve(bus_dmaengine_t dmaengine, unsigned n, int mflags)
1098 {
1099 	struct ioat_softc *ioat;
1100 	int error;
1101 
1102 	ioat = to_ioat_softc(dmaengine);
1103 	ioat_acquire(dmaengine);
1104 
1105 	error = ioat_reserve_space(ioat, n, mflags);
1106 	if (error != 0)
1107 		ioat_release(dmaengine);
1108 	return (error);
1109 }
1110 
1111 void
1112 ioat_release(bus_dmaengine_t dmaengine)
1113 {
1114 	struct ioat_softc *ioat;
1115 
1116 	ioat = to_ioat_softc(dmaengine);
1117 	CTR3(KTR_IOAT, "%s channel=%u dispatch1 head=%u", __func__,
1118 	    ioat->chan_idx, ioat->head);
1119 	KFAIL_POINT_CODE(DEBUG_FP, ioat_release, /* do nothing */);
1120 	CTR3(KTR_IOAT, "%s channel=%u dispatch2 head=%u", __func__,
1121 	    ioat->chan_idx, ioat->head);
1122 
1123 	if (ioat->acq_head != ioat->head) {
1124 		ioat_write_2(ioat, IOAT_DMACOUNT_OFFSET,
1125 		    (uint16_t)ioat->head);
1126 
1127 		if (!callout_pending(&ioat->poll_timer)) {
1128 			callout_reset_on(&ioat->poll_timer, 1,
1129 			    ioat_poll_timer_callback, ioat, ioat->cpu);
1130 		}
1131 	}
1132 	mtx_unlock(&ioat->submit_lock);
1133 }
1134 
1135 static struct ioat_descriptor *
1136 ioat_op_generic(struct ioat_softc *ioat, uint8_t op,
1137     uint32_t size, uint64_t src, uint64_t dst,
1138     bus_dmaengine_callback_t callback_fn, void *callback_arg,
1139     uint32_t flags)
1140 {
1141 	struct ioat_generic_hw_descriptor *hw_desc;
1142 	struct ioat_descriptor *desc;
1143 	bus_dma_segment_t seg;
1144 	int mflags, nseg, error;
1145 
1146 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1147 
1148 	KASSERT((flags & ~_DMA_GENERIC_FLAGS) == 0,
1149 	    ("Unrecognized flag(s): %#x", flags & ~_DMA_GENERIC_FLAGS));
1150 	KASSERT(size <= ioat->max_xfer_size, ("%s: size too big (%u > %u)",
1151 	    __func__, (unsigned)size, ioat->max_xfer_size));
1152 
1153 	if ((flags & DMA_NO_WAIT) != 0)
1154 		mflags = M_NOWAIT;
1155 	else
1156 		mflags = M_WAITOK;
1157 
1158 	if (ioat_reserve_space(ioat, 1, mflags) != 0)
1159 		return (NULL);
1160 
1161 	desc = ioat_get_ring_entry(ioat, ioat->head);
1162 	hw_desc = &ioat_get_descriptor(ioat, ioat->head)->generic;
1163 
1164 	hw_desc->u.control_raw = 0;
1165 	hw_desc->u.control_generic.op = op;
1166 	hw_desc->u.control_generic.completion_update = 1;
1167 
1168 	if ((flags & DMA_INT_EN) != 0)
1169 		hw_desc->u.control_generic.int_enable = 1;
1170 	if ((flags & DMA_FENCE) != 0)
1171 		hw_desc->u.control_generic.fence = 1;
1172 
1173 	hw_desc->size = size;
1174 
1175 	if (src != 0) {
1176 		nseg = -1;
1177 		error = _bus_dmamap_load_phys(ioat->data_tag, desc->src_dmamap,
1178 		    src, size, 0, &seg, &nseg);
1179 		if (error != 0) {
1180 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1181 			    " failed %d\n", __func__, error);
1182 			return (NULL);
1183 		}
1184 		hw_desc->src_addr = seg.ds_addr;
1185 	}
1186 
1187 	if (dst != 0) {
1188 		nseg = -1;
1189 		error = _bus_dmamap_load_phys(ioat->data_tag, desc->dst_dmamap,
1190 		    dst, size, 0, &seg, &nseg);
1191 		if (error != 0) {
1192 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1193 			    " failed %d\n", __func__, error);
1194 			return (NULL);
1195 		}
1196 		hw_desc->dest_addr = seg.ds_addr;
1197 	}
1198 
1199 	desc->bus_dmadesc.callback_fn = callback_fn;
1200 	desc->bus_dmadesc.callback_arg = callback_arg;
1201 	return (desc);
1202 }
1203 
1204 struct bus_dmadesc *
1205 ioat_null(bus_dmaengine_t dmaengine, bus_dmaengine_callback_t callback_fn,
1206     void *callback_arg, uint32_t flags)
1207 {
1208 	struct ioat_dma_hw_descriptor *hw_desc;
1209 	struct ioat_descriptor *desc;
1210 	struct ioat_softc *ioat;
1211 
1212 	ioat = to_ioat_softc(dmaengine);
1213 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1214 
1215 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, 8, 0, 0, callback_fn,
1216 	    callback_arg, flags);
1217 	if (desc == NULL)
1218 		return (NULL);
1219 
1220 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->dma;
1221 	hw_desc->u.control.null = 1;
1222 	ioat_submit_single(ioat);
1223 	return (&desc->bus_dmadesc);
1224 }
1225 
1226 struct bus_dmadesc *
1227 ioat_copy(bus_dmaengine_t dmaengine, bus_addr_t dst,
1228     bus_addr_t src, bus_size_t len, bus_dmaengine_callback_t callback_fn,
1229     void *callback_arg, uint32_t flags)
1230 {
1231 	struct ioat_dma_hw_descriptor *hw_desc;
1232 	struct ioat_descriptor *desc;
1233 	struct ioat_softc *ioat;
1234 
1235 	ioat = to_ioat_softc(dmaengine);
1236 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, len, src, dst, callback_fn,
1237 	    callback_arg, flags);
1238 	if (desc == NULL)
1239 		return (NULL);
1240 
1241 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->dma;
1242 	if (g_ioat_debug_level >= 3)
1243 		dump_descriptor(hw_desc);
1244 
1245 	ioat_submit_single(ioat);
1246 	CTR6(KTR_IOAT, "%s channel=%u desc=%p dest=%lx src=%lx len=%lx",
1247 	    __func__, ioat->chan_idx, &desc->bus_dmadesc, dst, src, len);
1248 	return (&desc->bus_dmadesc);
1249 }
1250 
1251 struct bus_dmadesc *
1252 ioat_copy_8k_aligned(bus_dmaengine_t dmaengine, bus_addr_t dst1,
1253     bus_addr_t dst2, bus_addr_t src1, bus_addr_t src2,
1254     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags)
1255 {
1256 	struct ioat_dma_hw_descriptor *hw_desc;
1257 	struct ioat_descriptor *desc;
1258 	struct ioat_softc *ioat;
1259 	bus_size_t src1_len, dst1_len;
1260 	bus_dma_segment_t seg;
1261 	int nseg, error;
1262 
1263 	ioat = to_ioat_softc(dmaengine);
1264 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1265 
1266 	KASSERT(((src1 | src2 | dst1 | dst2) & PAGE_MASK) == 0,
1267 	    ("%s: addresses are not page-aligned", __func__));
1268 
1269 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, 2 * PAGE_SIZE, 0, 0,
1270 	    callback_fn, callback_arg, flags);
1271 	if (desc == NULL)
1272 		return (NULL);
1273 
1274 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->dma;
1275 
1276 	src1_len = (src2 != src1 + PAGE_SIZE) ? PAGE_SIZE : 2 * PAGE_SIZE;
1277 	nseg = -1;
1278 	error = _bus_dmamap_load_phys(ioat->data_tag,
1279 	    desc->src_dmamap, src1, src1_len, 0, &seg, &nseg);
1280 	if (error != 0) {
1281 		ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1282 		    " failed %d\n", __func__, error);
1283 		return (NULL);
1284 	}
1285 	hw_desc->src_addr = seg.ds_addr;
1286 	if (src1_len != 2 * PAGE_SIZE) {
1287 		hw_desc->u.control.src_page_break = 1;
1288 		nseg = -1;
1289 		error = _bus_dmamap_load_phys(ioat->data_tag,
1290 		    desc->src2_dmamap, src2, PAGE_SIZE, 0, &seg, &nseg);
1291 		if (error != 0) {
1292 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1293 			    " failed %d\n", __func__, error);
1294 			return (NULL);
1295 		}
1296 		hw_desc->next_src_addr = seg.ds_addr;
1297 	}
1298 
1299 	dst1_len = (dst2 != dst1 + PAGE_SIZE) ? PAGE_SIZE : 2 * PAGE_SIZE;
1300 	nseg = -1;
1301 	error = _bus_dmamap_load_phys(ioat->data_tag,
1302 	    desc->dst_dmamap, dst1, dst1_len, 0, &seg, &nseg);
1303 	if (error != 0) {
1304 		ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1305 		    " failed %d\n", __func__, error);
1306 		return (NULL);
1307 	}
1308 	hw_desc->dest_addr = seg.ds_addr;
1309 	if (dst1_len != 2 * PAGE_SIZE) {
1310 		hw_desc->u.control.dest_page_break = 1;
1311 		nseg = -1;
1312 		error = _bus_dmamap_load_phys(ioat->data_tag,
1313 		    desc->dst2_dmamap, dst2, PAGE_SIZE, 0, &seg, &nseg);
1314 		if (error != 0) {
1315 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1316 			    " failed %d\n", __func__, error);
1317 			return (NULL);
1318 		}
1319 		hw_desc->next_dest_addr = seg.ds_addr;
1320 	}
1321 
1322 	if (g_ioat_debug_level >= 3)
1323 		dump_descriptor(hw_desc);
1324 
1325 	ioat_submit_single(ioat);
1326 	return (&desc->bus_dmadesc);
1327 }
1328 
1329 struct bus_dmadesc *
1330 ioat_copy_crc(bus_dmaengine_t dmaengine, bus_addr_t dst, bus_addr_t src,
1331     bus_size_t len, uint32_t *initialseed, bus_addr_t crcptr,
1332     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags)
1333 {
1334 	struct ioat_crc32_hw_descriptor *hw_desc;
1335 	struct ioat_descriptor *desc;
1336 	struct ioat_softc *ioat;
1337 	uint32_t teststore;
1338 	uint8_t op;
1339 	bus_dma_segment_t seg;
1340 	int nseg, error;
1341 
1342 	ioat = to_ioat_softc(dmaengine);
1343 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1344 
1345 	KASSERT((ioat->capabilities & IOAT_DMACAP_MOVECRC) != 0,
1346 	    ("%s: device lacks MOVECRC capability", __func__));
1347 	teststore = (flags & _DMA_CRC_TESTSTORE);
1348 	KASSERT(teststore != _DMA_CRC_TESTSTORE,
1349 	    ("%s: TEST and STORE invalid", __func__));
1350 	KASSERT(teststore != 0 || (flags & DMA_CRC_INLINE) == 0,
1351 	    ("%s: INLINE invalid without TEST or STORE", __func__));
1352 
1353 	switch (teststore) {
1354 	case DMA_CRC_STORE:
1355 		op = IOAT_OP_MOVECRC_STORE;
1356 		break;
1357 	case DMA_CRC_TEST:
1358 		op = IOAT_OP_MOVECRC_TEST;
1359 		break;
1360 	default:
1361 		KASSERT(teststore == 0, ("bogus"));
1362 		op = IOAT_OP_MOVECRC;
1363 		break;
1364 	}
1365 
1366 	desc = ioat_op_generic(ioat, op, len, src, dst, callback_fn,
1367 	    callback_arg, flags & ~_DMA_CRC_FLAGS);
1368 	if (desc == NULL)
1369 		return (NULL);
1370 
1371 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->crc32;
1372 
1373 	if ((flags & DMA_CRC_INLINE) == 0) {
1374 		nseg = -1;
1375 		error = _bus_dmamap_load_phys(ioat->data_tag,
1376 		    desc->dst2_dmamap, crcptr, sizeof(uint32_t), 0,
1377 		    &seg, &nseg);
1378 		if (error != 0) {
1379 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1380 			    " failed %d\n", __func__, error);
1381 			return (NULL);
1382 		}
1383 		hw_desc->crc_address = seg.ds_addr;
1384 	} else
1385 		hw_desc->u.control.crc_location = 1;
1386 
1387 	if (initialseed != NULL) {
1388 		hw_desc->u.control.use_seed = 1;
1389 		hw_desc->seed = *initialseed;
1390 	}
1391 
1392 	if (g_ioat_debug_level >= 3)
1393 		dump_descriptor(hw_desc);
1394 
1395 	ioat_submit_single(ioat);
1396 	return (&desc->bus_dmadesc);
1397 }
1398 
1399 struct bus_dmadesc *
1400 ioat_crc(bus_dmaengine_t dmaengine, bus_addr_t src, bus_size_t len,
1401     uint32_t *initialseed, bus_addr_t crcptr,
1402     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags)
1403 {
1404 	struct ioat_crc32_hw_descriptor *hw_desc;
1405 	struct ioat_descriptor *desc;
1406 	struct ioat_softc *ioat;
1407 	uint32_t teststore;
1408 	uint8_t op;
1409 	bus_dma_segment_t seg;
1410 	int nseg, error;
1411 
1412 	ioat = to_ioat_softc(dmaengine);
1413 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1414 
1415 	KASSERT((ioat->capabilities & IOAT_DMACAP_CRC) != 0,
1416 	    ("%s: device lacks CRC capability", __func__));
1417 	teststore = (flags & _DMA_CRC_TESTSTORE);
1418 	KASSERT(teststore != _DMA_CRC_TESTSTORE,
1419 	    ("%s: TEST and STORE invalid", __func__));
1420 	KASSERT(teststore != 0 || (flags & DMA_CRC_INLINE) == 0,
1421 	    ("%s: INLINE invalid without TEST or STORE", __func__));
1422 
1423 	switch (teststore) {
1424 	case DMA_CRC_STORE:
1425 		op = IOAT_OP_CRC_STORE;
1426 		break;
1427 	case DMA_CRC_TEST:
1428 		op = IOAT_OP_CRC_TEST;
1429 		break;
1430 	default:
1431 		KASSERT(teststore == 0, ("bogus"));
1432 		op = IOAT_OP_CRC;
1433 		break;
1434 	}
1435 
1436 	desc = ioat_op_generic(ioat, op, len, src, 0, callback_fn,
1437 	    callback_arg, flags & ~_DMA_CRC_FLAGS);
1438 	if (desc == NULL)
1439 		return (NULL);
1440 
1441 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->crc32;
1442 
1443 	if ((flags & DMA_CRC_INLINE) == 0) {
1444 		nseg = -1;
1445 		error = _bus_dmamap_load_phys(ioat->data_tag,
1446 		    desc->dst2_dmamap, crcptr, sizeof(uint32_t), 0,
1447 		    &seg, &nseg);
1448 		if (error != 0) {
1449 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1450 			    " failed %d\n", __func__, error);
1451 			return (NULL);
1452 		}
1453 		hw_desc->crc_address = seg.ds_addr;
1454 	} else
1455 		hw_desc->u.control.crc_location = 1;
1456 
1457 	if (initialseed != NULL) {
1458 		hw_desc->u.control.use_seed = 1;
1459 		hw_desc->seed = *initialseed;
1460 	}
1461 
1462 	if (g_ioat_debug_level >= 3)
1463 		dump_descriptor(hw_desc);
1464 
1465 	ioat_submit_single(ioat);
1466 	return (&desc->bus_dmadesc);
1467 }
1468 
1469 struct bus_dmadesc *
1470 ioat_blockfill(bus_dmaengine_t dmaengine, bus_addr_t dst, uint64_t fillpattern,
1471     bus_size_t len, bus_dmaengine_callback_t callback_fn, void *callback_arg,
1472     uint32_t flags)
1473 {
1474 	struct ioat_fill_hw_descriptor *hw_desc;
1475 	struct ioat_descriptor *desc;
1476 	struct ioat_softc *ioat;
1477 
1478 	ioat = to_ioat_softc(dmaengine);
1479 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1480 
1481 	KASSERT((ioat->capabilities & IOAT_DMACAP_BFILL) != 0,
1482 	    ("%s: device lacks BFILL capability", __func__));
1483 
1484 	desc = ioat_op_generic(ioat, IOAT_OP_FILL, len, 0, dst,
1485 	    callback_fn, callback_arg, flags);
1486 	if (desc == NULL)
1487 		return (NULL);
1488 
1489 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->fill;
1490 	hw_desc->src_data = fillpattern;
1491 	if (g_ioat_debug_level >= 3)
1492 		dump_descriptor(hw_desc);
1493 
1494 	ioat_submit_single(ioat);
1495 	return (&desc->bus_dmadesc);
1496 }
1497 
1498 /*
1499  * Ring Management
1500  */
1501 static inline uint32_t
1502 ioat_get_active(struct ioat_softc *ioat)
1503 {
1504 
1505 	return ((ioat->head - ioat->tail) & ((1 << ioat->ring_size_order) - 1));
1506 }
1507 
1508 static inline uint32_t
1509 ioat_get_ring_space(struct ioat_softc *ioat)
1510 {
1511 
1512 	return ((1 << ioat->ring_size_order) - ioat_get_active(ioat) - 1);
1513 }
1514 
1515 /*
1516  * Reserves space in this IOAT descriptor ring by ensuring enough slots remain
1517  * for 'num_descs'.
1518  *
1519  * If mflags contains M_WAITOK, blocks until enough space is available.
1520  *
1521  * Returns zero on success, or an errno on error.  If num_descs is beyond the
1522  * maximum ring size, returns EINVAl; if allocation would block and mflags
1523  * contains M_NOWAIT, returns EAGAIN.
1524  *
1525  * Must be called with the submit_lock held; returns with the lock held.  The
1526  * lock may be dropped to allocate the ring.
1527  *
1528  * (The submit_lock is needed to add any entries to the ring, so callers are
1529  * assured enough room is available.)
1530  */
1531 static int
1532 ioat_reserve_space(struct ioat_softc *ioat, uint32_t num_descs, int mflags)
1533 {
1534 	boolean_t dug;
1535 	int error;
1536 
1537 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1538 	error = 0;
1539 	dug = FALSE;
1540 
1541 	if (num_descs < 1 || num_descs >= (1 << ioat->ring_size_order)) {
1542 		error = EINVAL;
1543 		goto out;
1544 	}
1545 
1546 	for (;;) {
1547 		if (ioat->quiescing) {
1548 			error = ENXIO;
1549 			goto out;
1550 		}
1551 
1552 		if (ioat_get_ring_space(ioat) >= num_descs)
1553 			goto out;
1554 
1555 		CTR3(KTR_IOAT, "%s channel=%u starved (%u)", __func__,
1556 		    ioat->chan_idx, num_descs);
1557 
1558 		if (!dug && !ioat->is_submitter_processing) {
1559 			ioat->is_submitter_processing = TRUE;
1560 			mtx_unlock(&ioat->submit_lock);
1561 
1562 			CTR2(KTR_IOAT, "%s channel=%u attempting to process events",
1563 			    __func__, ioat->chan_idx);
1564 			ioat_process_events(ioat, FALSE);
1565 
1566 			mtx_lock(&ioat->submit_lock);
1567 			dug = TRUE;
1568 			KASSERT(ioat->is_submitter_processing == TRUE,
1569 			    ("is_submitter_processing"));
1570 			ioat->is_submitter_processing = FALSE;
1571 			wakeup(&ioat->tail);
1572 			continue;
1573 		}
1574 
1575 		if ((mflags & M_WAITOK) == 0) {
1576 			error = EAGAIN;
1577 			break;
1578 		}
1579 		CTR2(KTR_IOAT, "%s channel=%u blocking on completions",
1580 		    __func__, ioat->chan_idx);
1581 		msleep(&ioat->tail, &ioat->submit_lock, 0,
1582 		    "ioat_full", 0);
1583 		continue;
1584 	}
1585 
1586 out:
1587 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1588 	KASSERT(!ioat->quiescing || error == ENXIO,
1589 	    ("reserved during quiesce"));
1590 	return (error);
1591 }
1592 
1593 static void
1594 ioat_free_ring(struct ioat_softc *ioat, uint32_t size,
1595     struct ioat_descriptor *ring)
1596 {
1597 
1598 	free(ring, M_IOAT);
1599 }
1600 
1601 static struct ioat_descriptor *
1602 ioat_get_ring_entry(struct ioat_softc *ioat, uint32_t index)
1603 {
1604 
1605 	return (&ioat->ring[index % (1 << ioat->ring_size_order)]);
1606 }
1607 
1608 static union ioat_hw_descriptor *
1609 ioat_get_descriptor(struct ioat_softc *ioat, uint32_t index)
1610 {
1611 
1612 	return (&ioat->hw_desc_ring[index % (1 << ioat->ring_size_order)]);
1613 }
1614 
1615 static void
1616 ioat_halted_debug(struct ioat_softc *ioat, uint32_t chanerr)
1617 {
1618 	union ioat_hw_descriptor *desc;
1619 
1620 	ioat_log_message(0, "Channel halted (%b)\n", (int)chanerr,
1621 	    IOAT_CHANERR_STR);
1622 	if (chanerr == 0)
1623 		return;
1624 
1625 	mtx_assert(&ioat->cleanup_lock, MA_OWNED);
1626 
1627 	desc = ioat_get_descriptor(ioat, ioat->tail + 0);
1628 	dump_descriptor(desc);
1629 
1630 	desc = ioat_get_descriptor(ioat, ioat->tail + 1);
1631 	dump_descriptor(desc);
1632 }
1633 
1634 static void
1635 ioat_poll_timer_callback(void *arg)
1636 {
1637 	struct ioat_softc *ioat;
1638 
1639 	ioat = arg;
1640 	CTR1(KTR_IOAT, "%s", __func__);
1641 
1642 	ioat_process_events(ioat, FALSE);
1643 
1644 	mtx_lock(&ioat->submit_lock);
1645 	if (ioat_get_active(ioat) > 0)
1646 		callout_schedule(&ioat->poll_timer, 1);
1647 	mtx_unlock(&ioat->submit_lock);
1648 }
1649 
1650 /*
1651  * Support Functions
1652  */
1653 static void
1654 ioat_submit_single(struct ioat_softc *ioat)
1655 {
1656 
1657 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1658 
1659 	ioat->head++;
1660 	CTR4(KTR_IOAT, "%s channel=%u head=%u tail=%u", __func__,
1661 	    ioat->chan_idx, ioat->head, ioat->tail);
1662 
1663 	ioat->stats.descriptors_submitted++;
1664 }
1665 
1666 static int
1667 ioat_reset_hw(struct ioat_softc *ioat)
1668 {
1669 	uint64_t status;
1670 	uint32_t chanerr;
1671 	unsigned timeout;
1672 	int error;
1673 
1674 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1675 
1676 	mtx_lock(&ioat->submit_lock);
1677 	while (ioat->resetting && !ioat->destroying)
1678 		msleep(&ioat->resetting, &ioat->submit_lock, 0, "IRH_drain", 0);
1679 	if (ioat->destroying) {
1680 		mtx_unlock(&ioat->submit_lock);
1681 		return (ENXIO);
1682 	}
1683 	ioat->resetting = TRUE;
1684 	ioat->quiescing = TRUE;
1685 	mtx_unlock(&ioat->submit_lock);
1686 	mtx_lock(&ioat->cleanup_lock);
1687 	while (ioat_get_active(ioat) > 0)
1688 		msleep(&ioat->tail, &ioat->cleanup_lock, 0, "ioat_drain", 1);
1689 
1690 	/*
1691 	 * Suspend ioat_process_events while the hardware and softc are in an
1692 	 * indeterminate state.
1693 	 */
1694 	ioat->resetting_cleanup = TRUE;
1695 	mtx_unlock(&ioat->cleanup_lock);
1696 
1697 	CTR2(KTR_IOAT, "%s channel=%u quiesced and drained", __func__,
1698 	    ioat->chan_idx);
1699 
1700 	status = ioat_get_chansts(ioat);
1701 	if (is_ioat_active(status) || is_ioat_idle(status))
1702 		ioat_suspend(ioat);
1703 
1704 	/* Wait at most 20 ms */
1705 	for (timeout = 0; (is_ioat_active(status) || is_ioat_idle(status)) &&
1706 	    timeout < 20; timeout++) {
1707 		DELAY(1000);
1708 		status = ioat_get_chansts(ioat);
1709 	}
1710 	if (timeout == 20) {
1711 		error = ETIMEDOUT;
1712 		goto out;
1713 	}
1714 
1715 	KASSERT(ioat_get_active(ioat) == 0, ("active after quiesce"));
1716 
1717 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
1718 	ioat_write_4(ioat, IOAT_CHANERR_OFFSET, chanerr);
1719 
1720 	CTR2(KTR_IOAT, "%s channel=%u hardware suspended", __func__,
1721 	    ioat->chan_idx);
1722 
1723 	/*
1724 	 * IOAT v3 workaround - CHANERRMSK_INT with 3E07h to masks out errors
1725 	 *  that can cause stability issues for IOAT v3.
1726 	 */
1727 	pci_write_config(ioat->device, IOAT_CFG_CHANERRMASK_INT_OFFSET, 0x3e07,
1728 	    4);
1729 	chanerr = pci_read_config(ioat->device, IOAT_CFG_CHANERR_INT_OFFSET, 4);
1730 	pci_write_config(ioat->device, IOAT_CFG_CHANERR_INT_OFFSET, chanerr, 4);
1731 
1732 	/*
1733 	 * BDXDE and BWD models reset MSI-X registers on device reset.
1734 	 * Save/restore their contents manually.
1735 	 */
1736 	if (ioat_model_resets_msix(ioat)) {
1737 		ioat_log_message(1, "device resets MSI-X registers; saving\n");
1738 		pci_save_state(ioat->device);
1739 	}
1740 
1741 	ioat_reset(ioat);
1742 	CTR2(KTR_IOAT, "%s channel=%u hardware reset", __func__,
1743 	    ioat->chan_idx);
1744 
1745 	/* Wait at most 20 ms */
1746 	for (timeout = 0; ioat_reset_pending(ioat) && timeout < 20; timeout++)
1747 		DELAY(1000);
1748 	if (timeout == 20) {
1749 		error = ETIMEDOUT;
1750 		goto out;
1751 	}
1752 
1753 	if (ioat_model_resets_msix(ioat)) {
1754 		ioat_log_message(1, "device resets registers; restored\n");
1755 		pci_restore_state(ioat->device);
1756 	}
1757 
1758 	/* Reset attempts to return the hardware to "halted." */
1759 	status = ioat_get_chansts(ioat);
1760 	if (is_ioat_active(status) || is_ioat_idle(status)) {
1761 		/* So this really shouldn't happen... */
1762 		ioat_log_message(0, "Device is active after a reset?\n");
1763 		ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
1764 		error = 0;
1765 		goto out;
1766 	}
1767 
1768 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
1769 	if (chanerr != 0) {
1770 		mtx_lock(&ioat->cleanup_lock);
1771 		ioat_halted_debug(ioat, chanerr);
1772 		mtx_unlock(&ioat->cleanup_lock);
1773 		error = EIO;
1774 		goto out;
1775 	}
1776 
1777 	/*
1778 	 * Bring device back online after reset.  Writing CHAINADDR brings the
1779 	 * device back to active.
1780 	 *
1781 	 * The internal ring counter resets to zero, so we have to start over
1782 	 * at zero as well.
1783 	 */
1784 	ioat->tail = ioat->head = 0;
1785 	*ioat->comp_update = ioat->last_seen =
1786 	    RING_PHYS_ADDR(ioat, ioat->tail - 1);
1787 
1788 	ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
1789 	ioat_write_chancmp(ioat, ioat->comp_update_bus_addr);
1790 	ioat_write_chainaddr(ioat, RING_PHYS_ADDR(ioat, 0));
1791 	error = 0;
1792 	CTR2(KTR_IOAT, "%s channel=%u configured channel", __func__,
1793 	    ioat->chan_idx);
1794 
1795 out:
1796 	/* Enqueues a null operation and ensures it completes. */
1797 	if (error == 0) {
1798 		error = ioat_start_channel(ioat);
1799 		CTR2(KTR_IOAT, "%s channel=%u started channel", __func__,
1800 		    ioat->chan_idx);
1801 	}
1802 
1803 	/*
1804 	 * Resume completions now that ring state is consistent.
1805 	 */
1806 	mtx_lock(&ioat->cleanup_lock);
1807 	ioat->resetting_cleanup = FALSE;
1808 	mtx_unlock(&ioat->cleanup_lock);
1809 
1810 	/* Unblock submission of new work */
1811 	mtx_lock(&ioat->submit_lock);
1812 	ioat->quiescing = FALSE;
1813 	wakeup(&ioat->quiescing);
1814 
1815 	ioat->resetting = FALSE;
1816 	wakeup(&ioat->resetting);
1817 
1818 	CTR2(KTR_IOAT, "%s channel=%u reset done", __func__, ioat->chan_idx);
1819 	mtx_unlock(&ioat->submit_lock);
1820 
1821 	return (error);
1822 }
1823 
1824 static int
1825 sysctl_handle_chansts(SYSCTL_HANDLER_ARGS)
1826 {
1827 	struct ioat_softc *ioat;
1828 	struct sbuf sb;
1829 	uint64_t status;
1830 	int error;
1831 
1832 	ioat = arg1;
1833 
1834 	status = ioat_get_chansts(ioat) & IOAT_CHANSTS_STATUS;
1835 
1836 	sbuf_new_for_sysctl(&sb, NULL, 256, req);
1837 	switch (status) {
1838 	case IOAT_CHANSTS_ACTIVE:
1839 		sbuf_printf(&sb, "ACTIVE");
1840 		break;
1841 	case IOAT_CHANSTS_IDLE:
1842 		sbuf_printf(&sb, "IDLE");
1843 		break;
1844 	case IOAT_CHANSTS_SUSPENDED:
1845 		sbuf_printf(&sb, "SUSPENDED");
1846 		break;
1847 	case IOAT_CHANSTS_HALTED:
1848 		sbuf_printf(&sb, "HALTED");
1849 		break;
1850 	case IOAT_CHANSTS_ARMED:
1851 		sbuf_printf(&sb, "ARMED");
1852 		break;
1853 	default:
1854 		sbuf_printf(&sb, "UNKNOWN");
1855 		break;
1856 	}
1857 	error = sbuf_finish(&sb);
1858 	sbuf_delete(&sb);
1859 
1860 	if (error != 0 || req->newptr == NULL)
1861 		return (error);
1862 	return (EINVAL);
1863 }
1864 
1865 static int
1866 sysctl_handle_dpi(SYSCTL_HANDLER_ARGS)
1867 {
1868 	struct ioat_softc *ioat;
1869 	struct sbuf sb;
1870 #define	PRECISION	"1"
1871 	const uintmax_t factor = 10;
1872 	uintmax_t rate;
1873 	int error;
1874 
1875 	ioat = arg1;
1876 	sbuf_new_for_sysctl(&sb, NULL, 16, req);
1877 
1878 	if (ioat->stats.interrupts == 0) {
1879 		sbuf_printf(&sb, "NaN");
1880 		goto out;
1881 	}
1882 	rate = ioat->stats.descriptors_processed * factor /
1883 	    ioat->stats.interrupts;
1884 	sbuf_printf(&sb, "%ju.%." PRECISION "ju", rate / factor,
1885 	    rate % factor);
1886 #undef	PRECISION
1887 out:
1888 	error = sbuf_finish(&sb);
1889 	sbuf_delete(&sb);
1890 	if (error != 0 || req->newptr == NULL)
1891 		return (error);
1892 	return (EINVAL);
1893 }
1894 
1895 static int
1896 sysctl_handle_reset(SYSCTL_HANDLER_ARGS)
1897 {
1898 	struct ioat_softc *ioat;
1899 	int error, arg;
1900 
1901 	ioat = arg1;
1902 
1903 	arg = 0;
1904 	error = SYSCTL_OUT(req, &arg, sizeof(arg));
1905 	if (error != 0 || req->newptr == NULL)
1906 		return (error);
1907 
1908 	error = SYSCTL_IN(req, &arg, sizeof(arg));
1909 	if (error != 0)
1910 		return (error);
1911 
1912 	if (arg != 0)
1913 		error = ioat_reset_hw(ioat);
1914 
1915 	return (error);
1916 }
1917 
1918 static void
1919 dump_descriptor(void *hw_desc)
1920 {
1921 	int i, j;
1922 
1923 	for (i = 0; i < 2; i++) {
1924 		for (j = 0; j < 8; j++)
1925 			printf("%08x ", ((uint32_t *)hw_desc)[i * 8 + j]);
1926 		printf("\n");
1927 	}
1928 }
1929 
1930 static void
1931 ioat_setup_sysctl(device_t device)
1932 {
1933 	struct sysctl_oid_list *par, *statpar, *state, *hammer;
1934 	struct sysctl_ctx_list *ctx;
1935 	struct sysctl_oid *tree, *tmp;
1936 	struct ioat_softc *ioat;
1937 
1938 	ioat = DEVICE2SOFTC(device);
1939 	ctx = device_get_sysctl_ctx(device);
1940 	tree = device_get_sysctl_tree(device);
1941 	par = SYSCTL_CHILDREN(tree);
1942 
1943 	SYSCTL_ADD_INT(ctx, par, OID_AUTO, "version", CTLFLAG_RD,
1944 	    &ioat->version, 0, "HW version (0xMM form)");
1945 	SYSCTL_ADD_UINT(ctx, par, OID_AUTO, "max_xfer_size", CTLFLAG_RD,
1946 	    &ioat->max_xfer_size, 0, "HW maximum transfer size");
1947 	SYSCTL_ADD_INT(ctx, par, OID_AUTO, "intrdelay_supported", CTLFLAG_RD,
1948 	    &ioat->intrdelay_supported, 0, "Is INTRDELAY supported");
1949 	SYSCTL_ADD_U16(ctx, par, OID_AUTO, "intrdelay_max", CTLFLAG_RD,
1950 	    &ioat->intrdelay_max, 0,
1951 	    "Maximum configurable INTRDELAY on this channel (microseconds)");
1952 
1953 	tmp = SYSCTL_ADD_NODE(ctx, par, OID_AUTO, "state",
1954 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "IOAT channel internal state");
1955 	state = SYSCTL_CHILDREN(tmp);
1956 
1957 	SYSCTL_ADD_UINT(ctx, state, OID_AUTO, "ring_size_order", CTLFLAG_RD,
1958 	    &ioat->ring_size_order, 0, "SW descriptor ring size order");
1959 	SYSCTL_ADD_UINT(ctx, state, OID_AUTO, "head", CTLFLAG_RD, &ioat->head,
1960 	    0, "SW descriptor head pointer index");
1961 	SYSCTL_ADD_UINT(ctx, state, OID_AUTO, "tail", CTLFLAG_RD, &ioat->tail,
1962 	    0, "SW descriptor tail pointer index");
1963 
1964 	SYSCTL_ADD_UQUAD(ctx, state, OID_AUTO, "last_completion", CTLFLAG_RD,
1965 	    ioat->comp_update, "HW addr of last completion");
1966 
1967 	SYSCTL_ADD_INT(ctx, state, OID_AUTO, "is_submitter_processing",
1968 	    CTLFLAG_RD, &ioat->is_submitter_processing, 0,
1969 	    "submitter processing");
1970 
1971 	SYSCTL_ADD_PROC(ctx, state, OID_AUTO, "chansts",
1972 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, ioat, 0,
1973 	    sysctl_handle_chansts, "A", "String of the channel status");
1974 
1975 	SYSCTL_ADD_U16(ctx, state, OID_AUTO, "intrdelay", CTLFLAG_RD,
1976 	    &ioat->cached_intrdelay, 0,
1977 	    "Current INTRDELAY on this channel (cached, microseconds)");
1978 
1979 	tmp = SYSCTL_ADD_NODE(ctx, par, OID_AUTO, "hammer",
1980 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
1981 	    "Big hammers (mostly for testing)");
1982 	hammer = SYSCTL_CHILDREN(tmp);
1983 
1984 	SYSCTL_ADD_PROC(ctx, hammer, OID_AUTO, "force_hw_reset",
1985 	    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, ioat, 0,
1986 	    sysctl_handle_reset, "I", "Set to non-zero to reset the hardware");
1987 
1988 	tmp = SYSCTL_ADD_NODE(ctx, par, OID_AUTO, "stats",
1989 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "IOAT channel statistics");
1990 	statpar = SYSCTL_CHILDREN(tmp);
1991 
1992 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "interrupts",
1993 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.interrupts,
1994 	    "Number of interrupts processed on this channel");
1995 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "descriptors",
1996 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.descriptors_processed,
1997 	    "Number of descriptors processed on this channel");
1998 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "submitted",
1999 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.descriptors_submitted,
2000 	    "Number of descriptors submitted to this channel");
2001 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "errored",
2002 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.descriptors_error,
2003 	    "Number of descriptors failed by channel errors");
2004 	SYSCTL_ADD_U32(ctx, statpar, OID_AUTO, "halts",
2005 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.channel_halts, 0,
2006 	    "Number of times the channel has halted");
2007 	SYSCTL_ADD_U32(ctx, statpar, OID_AUTO, "last_halt_chanerr",
2008 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.last_halt_chanerr, 0,
2009 	    "The raw CHANERR when the channel was last halted");
2010 
2011 	SYSCTL_ADD_PROC(ctx, statpar, OID_AUTO, "desc_per_interrupt",
2012 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, ioat, 0,
2013 	    sysctl_handle_dpi, "A", "Descriptors per interrupt");
2014 }
2015 
2016 static void
2017 ioat_get(struct ioat_softc *ioat)
2018 {
2019 
2020 	mtx_assert(&ioat->submit_lock, MA_OWNED);
2021 	KASSERT(ioat->refcnt < UINT32_MAX, ("refcnt overflow"));
2022 
2023 	ioat->refcnt++;
2024 }
2025 
2026 static void
2027 ioat_put(struct ioat_softc *ioat)
2028 {
2029 
2030 	mtx_assert(&ioat->submit_lock, MA_OWNED);
2031 	KASSERT(ioat->refcnt >= 1, ("refcnt error"));
2032 
2033 	if (--ioat->refcnt == 0)
2034 		wakeup(&ioat->refcnt);
2035 }
2036 
2037 static void
2038 ioat_drain_locked(struct ioat_softc *ioat)
2039 {
2040 
2041 	mtx_assert(&ioat->submit_lock, MA_OWNED);
2042 
2043 	while (ioat->refcnt > 0)
2044 		msleep(&ioat->refcnt, &ioat->submit_lock, 0, "ioat_drain", 0);
2045 }
2046 
2047 #ifdef DDB
2048 #define	_db_show_lock(lo)	LOCK_CLASS(lo)->lc_ddb_show(lo)
2049 #define	db_show_lock(lk)	_db_show_lock(&(lk)->lock_object)
2050 DB_SHOW_COMMAND(ioat, db_show_ioat)
2051 {
2052 	struct ioat_softc *sc;
2053 	unsigned idx;
2054 
2055 	if (!have_addr)
2056 		goto usage;
2057 	idx = (unsigned)addr;
2058 	if (idx >= ioat_channel_index)
2059 		goto usage;
2060 
2061 	sc = ioat_channel[idx];
2062 	db_printf("ioat softc at %p\n", sc);
2063 	if (sc == NULL)
2064 		return;
2065 
2066 	db_printf(" version: %d\n", sc->version);
2067 	db_printf(" chan_idx: %u\n", sc->chan_idx);
2068 	db_printf(" submit_lock: ");
2069 	db_show_lock(&sc->submit_lock);
2070 
2071 	db_printf(" capabilities: %b\n", (int)sc->capabilities,
2072 	    IOAT_DMACAP_STR);
2073 	db_printf(" cached_intrdelay: %u\n", sc->cached_intrdelay);
2074 	db_printf(" *comp_update: 0x%jx\n", (uintmax_t)*sc->comp_update);
2075 
2076 	db_printf(" poll_timer:\n");
2077 	db_printf("  c_time: %ju\n", (uintmax_t)sc->poll_timer.c_time);
2078 	db_printf("  c_arg: %p\n", sc->poll_timer.c_arg);
2079 	db_printf("  c_func: %p\n", sc->poll_timer.c_func);
2080 	db_printf("  c_lock: %p\n", sc->poll_timer.c_lock);
2081 	db_printf("  c_flags: 0x%x\n", (unsigned)sc->poll_timer.c_flags);
2082 
2083 	db_printf(" quiescing: %d\n", (int)sc->quiescing);
2084 	db_printf(" destroying: %d\n", (int)sc->destroying);
2085 	db_printf(" is_submitter_processing: %d\n",
2086 	    (int)sc->is_submitter_processing);
2087 	db_printf(" intrdelay_supported: %d\n", (int)sc->intrdelay_supported);
2088 	db_printf(" resetting: %d\n", (int)sc->resetting);
2089 
2090 	db_printf(" head: %u\n", sc->head);
2091 	db_printf(" tail: %u\n", sc->tail);
2092 	db_printf(" ring_size_order: %u\n", sc->ring_size_order);
2093 	db_printf(" last_seen: 0x%lx\n", sc->last_seen);
2094 	db_printf(" ring: %p\n", sc->ring);
2095 	db_printf(" descriptors: %p\n", sc->hw_desc_ring);
2096 	db_printf(" descriptors (phys): 0x%jx\n",
2097 	    (uintmax_t)sc->hw_desc_bus_addr);
2098 
2099 	db_printf("  ring[%u] (tail):\n", sc->tail %
2100 	    (1 << sc->ring_size_order));
2101 	db_printf("   id: %u\n", ioat_get_ring_entry(sc, sc->tail)->id);
2102 	db_printf("   addr: 0x%lx\n",
2103 	    RING_PHYS_ADDR(sc, sc->tail));
2104 	db_printf("   next: 0x%lx\n",
2105 	     ioat_get_descriptor(sc, sc->tail)->generic.next);
2106 
2107 	db_printf("  ring[%u] (head - 1):\n", (sc->head - 1) %
2108 	    (1 << sc->ring_size_order));
2109 	db_printf("   id: %u\n", ioat_get_ring_entry(sc, sc->head - 1)->id);
2110 	db_printf("   addr: 0x%lx\n",
2111 	    RING_PHYS_ADDR(sc, sc->head - 1));
2112 	db_printf("   next: 0x%lx\n",
2113 	     ioat_get_descriptor(sc, sc->head - 1)->generic.next);
2114 
2115 	db_printf("  ring[%u] (head):\n", (sc->head) %
2116 	    (1 << sc->ring_size_order));
2117 	db_printf("   id: %u\n", ioat_get_ring_entry(sc, sc->head)->id);
2118 	db_printf("   addr: 0x%lx\n",
2119 	    RING_PHYS_ADDR(sc, sc->head));
2120 	db_printf("   next: 0x%lx\n",
2121 	     ioat_get_descriptor(sc, sc->head)->generic.next);
2122 
2123 	for (idx = 0; idx < (1 << sc->ring_size_order); idx++)
2124 		if ((*sc->comp_update & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_MASK)
2125 		    == RING_PHYS_ADDR(sc, idx))
2126 			db_printf("  ring[%u] == hardware tail\n", idx);
2127 
2128 	db_printf(" cleanup_lock: ");
2129 	db_show_lock(&sc->cleanup_lock);
2130 
2131 	db_printf(" refcnt: %u\n", sc->refcnt);
2132 	db_printf(" stats:\n");
2133 	db_printf("  interrupts: %lu\n", sc->stats.interrupts);
2134 	db_printf("  descriptors_processed: %lu\n", sc->stats.descriptors_processed);
2135 	db_printf("  descriptors_error: %lu\n", sc->stats.descriptors_error);
2136 	db_printf("  descriptors_submitted: %lu\n", sc->stats.descriptors_submitted);
2137 
2138 	db_printf("  channel_halts: %u\n", sc->stats.channel_halts);
2139 	db_printf("  last_halt_chanerr: %u\n", sc->stats.last_halt_chanerr);
2140 
2141 	if (db_pager_quit)
2142 		return;
2143 
2144 	db_printf(" hw status:\n");
2145 	db_printf("  status: 0x%lx\n", ioat_get_chansts(sc));
2146 	db_printf("  chanctrl: 0x%x\n",
2147 	    (unsigned)ioat_read_2(sc, IOAT_CHANCTRL_OFFSET));
2148 	db_printf("  chancmd: 0x%x\n",
2149 	    (unsigned)ioat_read_1(sc, IOAT_CHANCMD_OFFSET));
2150 	db_printf("  dmacount: 0x%x\n",
2151 	    (unsigned)ioat_read_2(sc, IOAT_DMACOUNT_OFFSET));
2152 	db_printf("  chainaddr: 0x%lx\n",
2153 	    ioat_read_double_4(sc, IOAT_CHAINADDR_OFFSET_LOW));
2154 	db_printf("  chancmp: 0x%lx\n",
2155 	    ioat_read_double_4(sc, IOAT_CHANCMP_OFFSET_LOW));
2156 	db_printf("  chanerr: %b\n",
2157 	    (int)ioat_read_4(sc, IOAT_CHANERR_OFFSET), IOAT_CHANERR_STR);
2158 	return;
2159 usage:
2160 	db_printf("usage: show ioat <0-%u>\n", ioat_channel_index);
2161 	return;
2162 }
2163 #endif /* DDB */
2164