xref: /freebsd/sys/dev/ioat/ioat.c (revision 105fd928b0b5b35ab529e5f6914788dc49582901)
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 static devclass_t ioat_devclass;
151 DRIVER_MODULE(ioat, pci, ioat_pci_driver, ioat_devclass, ioat_modevent, NULL);
152 MODULE_VERSION(ioat, 1);
153 
154 /*
155  * Private data structures
156  */
157 static struct ioat_softc *ioat_channel[IOAT_MAX_CHANNELS];
158 static unsigned ioat_channel_index = 0;
159 SYSCTL_UINT(_hw_ioat, OID_AUTO, channels, CTLFLAG_RD, &ioat_channel_index, 0,
160     "Number of IOAT channels attached");
161 static struct mtx ioat_list_mtx;
162 MTX_SYSINIT(ioat_list_mtx, &ioat_list_mtx, "ioat list mtx", MTX_DEF);
163 
164 static struct _pcsid
165 {
166 	u_int32_t   type;
167 	const char  *desc;
168 } pci_ids[] = {
169 	{ 0x34308086, "TBG IOAT Ch0" },
170 	{ 0x34318086, "TBG IOAT Ch1" },
171 	{ 0x34328086, "TBG IOAT Ch2" },
172 	{ 0x34338086, "TBG IOAT Ch3" },
173 	{ 0x34298086, "TBG IOAT Ch4" },
174 	{ 0x342a8086, "TBG IOAT Ch5" },
175 	{ 0x342b8086, "TBG IOAT Ch6" },
176 	{ 0x342c8086, "TBG IOAT Ch7" },
177 
178 	{ 0x37108086, "JSF IOAT Ch0" },
179 	{ 0x37118086, "JSF IOAT Ch1" },
180 	{ 0x37128086, "JSF IOAT Ch2" },
181 	{ 0x37138086, "JSF IOAT Ch3" },
182 	{ 0x37148086, "JSF IOAT Ch4" },
183 	{ 0x37158086, "JSF IOAT Ch5" },
184 	{ 0x37168086, "JSF IOAT Ch6" },
185 	{ 0x37178086, "JSF IOAT Ch7" },
186 	{ 0x37188086, "JSF IOAT Ch0 (RAID)" },
187 	{ 0x37198086, "JSF IOAT Ch1 (RAID)" },
188 
189 	{ 0x3c208086, "SNB IOAT Ch0" },
190 	{ 0x3c218086, "SNB IOAT Ch1" },
191 	{ 0x3c228086, "SNB IOAT Ch2" },
192 	{ 0x3c238086, "SNB IOAT Ch3" },
193 	{ 0x3c248086, "SNB IOAT Ch4" },
194 	{ 0x3c258086, "SNB IOAT Ch5" },
195 	{ 0x3c268086, "SNB IOAT Ch6" },
196 	{ 0x3c278086, "SNB IOAT Ch7" },
197 	{ 0x3c2e8086, "SNB IOAT Ch0 (RAID)" },
198 	{ 0x3c2f8086, "SNB IOAT Ch1 (RAID)" },
199 
200 	{ 0x0e208086, "IVB IOAT Ch0" },
201 	{ 0x0e218086, "IVB IOAT Ch1" },
202 	{ 0x0e228086, "IVB IOAT Ch2" },
203 	{ 0x0e238086, "IVB IOAT Ch3" },
204 	{ 0x0e248086, "IVB IOAT Ch4" },
205 	{ 0x0e258086, "IVB IOAT Ch5" },
206 	{ 0x0e268086, "IVB IOAT Ch6" },
207 	{ 0x0e278086, "IVB IOAT Ch7" },
208 	{ 0x0e2e8086, "IVB IOAT Ch0 (RAID)" },
209 	{ 0x0e2f8086, "IVB IOAT Ch1 (RAID)" },
210 
211 	{ 0x2f208086, "HSW IOAT Ch0" },
212 	{ 0x2f218086, "HSW IOAT Ch1" },
213 	{ 0x2f228086, "HSW IOAT Ch2" },
214 	{ 0x2f238086, "HSW IOAT Ch3" },
215 	{ 0x2f248086, "HSW IOAT Ch4" },
216 	{ 0x2f258086, "HSW IOAT Ch5" },
217 	{ 0x2f268086, "HSW IOAT Ch6" },
218 	{ 0x2f278086, "HSW IOAT Ch7" },
219 	{ 0x2f2e8086, "HSW IOAT Ch0 (RAID)" },
220 	{ 0x2f2f8086, "HSW IOAT Ch1 (RAID)" },
221 
222 	{ 0x0c508086, "BWD IOAT Ch0" },
223 	{ 0x0c518086, "BWD IOAT Ch1" },
224 	{ 0x0c528086, "BWD IOAT Ch2" },
225 	{ 0x0c538086, "BWD IOAT Ch3" },
226 
227 	{ 0x6f508086, "BDXDE IOAT Ch0" },
228 	{ 0x6f518086, "BDXDE IOAT Ch1" },
229 	{ 0x6f528086, "BDXDE IOAT Ch2" },
230 	{ 0x6f538086, "BDXDE IOAT Ch3" },
231 
232 	{ 0x6f208086, "BDX IOAT Ch0" },
233 	{ 0x6f218086, "BDX IOAT Ch1" },
234 	{ 0x6f228086, "BDX IOAT Ch2" },
235 	{ 0x6f238086, "BDX IOAT Ch3" },
236 	{ 0x6f248086, "BDX IOAT Ch4" },
237 	{ 0x6f258086, "BDX IOAT Ch5" },
238 	{ 0x6f268086, "BDX IOAT Ch6" },
239 	{ 0x6f278086, "BDX IOAT Ch7" },
240 	{ 0x6f2e8086, "BDX IOAT Ch0 (RAID)" },
241 	{ 0x6f2f8086, "BDX IOAT Ch1 (RAID)" },
242 
243 	{ 0x20218086, "SKX IOAT" },
244 };
245 
246 MODULE_PNP_INFO("W32:vendor/device;D:#", pci, ioat, pci_ids,
247     nitems(pci_ids));
248 
249 /*
250  * OS <-> Driver linkage functions
251  */
252 static int
253 ioat_modevent(module_t mod __unused, int type, void *data __unused)
254 {
255 	switch(type) {
256 	case MOD_LOAD:
257 		break;
258 
259 	case MOD_UNLOAD:
260 		ioat_test_detach();
261 		break;
262 
263 	case MOD_SHUTDOWN:
264 		break;
265 
266 	default:
267 		return (EOPNOTSUPP);
268 	}
269 
270 	return (0);
271 }
272 
273 static int
274 ioat_probe(device_t device)
275 {
276 	struct _pcsid *ep;
277 	u_int32_t type;
278 
279 	type = pci_get_devid(device);
280 	for (ep = pci_ids; ep < &pci_ids[nitems(pci_ids)]; ep++) {
281 		if (ep->type == type) {
282 			device_set_desc(device, ep->desc);
283 			return (0);
284 		}
285 	}
286 	return (ENXIO);
287 }
288 
289 static int
290 ioat_attach(device_t device)
291 {
292 	struct ioat_softc *ioat;
293 	int error, i;
294 
295 	ioat = DEVICE2SOFTC(device);
296 	ioat->device = device;
297 	if (bus_get_domain(device, &ioat->domain) != 0)
298 		ioat->domain = 0;
299 	ioat->cpu = CPU_FFS(&cpuset_domain[ioat->domain]) - 1;
300 	if (ioat->cpu < 0)
301 		ioat->cpu = CPU_FIRST();
302 
303 	error = ioat_map_pci_bar(ioat);
304 	if (error != 0)
305 		goto err;
306 
307 	ioat->version = ioat_read_cbver(ioat);
308 	if (ioat->version < IOAT_VER_3_0) {
309 		error = ENODEV;
310 		goto err;
311 	}
312 
313 	error = ioat3_attach(device);
314 	if (error != 0)
315 		goto err;
316 
317 	error = pci_enable_busmaster(device);
318 	if (error != 0)
319 		goto err;
320 
321 	error = ioat_setup_intr(ioat);
322 	if (error != 0)
323 		goto err;
324 
325 	error = ioat_reset_hw(ioat);
326 	if (error != 0)
327 		goto err;
328 
329 	ioat_process_events(ioat, FALSE);
330 	ioat_setup_sysctl(device);
331 
332 	mtx_lock(&ioat_list_mtx);
333 	for (i = 0; i < IOAT_MAX_CHANNELS; i++) {
334 		if (ioat_channel[i] == NULL)
335 			break;
336 	}
337 	if (i >= IOAT_MAX_CHANNELS) {
338 		mtx_unlock(&ioat_list_mtx);
339 		device_printf(device, "Too many I/OAT devices in system\n");
340 		error = ENXIO;
341 		goto err;
342 	}
343 	ioat->chan_idx = i;
344 	ioat_channel[i] = ioat;
345 	if (i >= ioat_channel_index)
346 		ioat_channel_index = i + 1;
347 	mtx_unlock(&ioat_list_mtx);
348 
349 	ioat_test_attach();
350 
351 err:
352 	if (error != 0)
353 		ioat_detach(device);
354 	return (error);
355 }
356 
357 static inline int
358 ioat_bus_dmamap_destroy(struct ioat_softc *ioat, const char *func,
359     bus_dma_tag_t dmat, bus_dmamap_t map)
360 {
361 	int error;
362 
363 	error = bus_dmamap_destroy(dmat, map);
364 	if (error != 0) {
365 		ioat_log_message(0,
366 		    "%s: bus_dmamap_destroy failed %d\n", func, error);
367 	}
368 
369 	return (error);
370 }
371 
372 static int
373 ioat_detach(device_t device)
374 {
375 	struct ioat_softc *ioat;
376 	int i, error;
377 
378 	ioat = DEVICE2SOFTC(device);
379 
380 	mtx_lock(&ioat_list_mtx);
381 	ioat_channel[ioat->chan_idx] = NULL;
382 	while (ioat_channel_index > 0 &&
383 	    ioat_channel[ioat_channel_index - 1] == NULL)
384 		ioat_channel_index--;
385 	mtx_unlock(&ioat_list_mtx);
386 
387 	taskqueue_drain(taskqueue_thread, &ioat->reset_task);
388 
389 	mtx_lock(&ioat->submit_lock);
390 	ioat->quiescing = TRUE;
391 	ioat->destroying = TRUE;
392 	wakeup(&ioat->quiescing);
393 	wakeup(&ioat->resetting);
394 
395 	ioat_drain_locked(ioat);
396 	mtx_unlock(&ioat->submit_lock);
397 	mtx_lock(&ioat->cleanup_lock);
398 	while (ioat_get_active(ioat) > 0)
399 		msleep(&ioat->tail, &ioat->cleanup_lock, 0, "ioat_drain", 1);
400 	mtx_unlock(&ioat->cleanup_lock);
401 
402 	ioat_teardown_intr(ioat);
403 	callout_drain(&ioat->poll_timer);
404 
405 	pci_disable_busmaster(device);
406 
407 	if (ioat->pci_resource != NULL)
408 		bus_release_resource(device, SYS_RES_MEMORY,
409 		    ioat->pci_resource_id, ioat->pci_resource);
410 
411 	if (ioat->data_tag != NULL) {
412 		for (i = 0; i < 1 << ioat->ring_size_order; i++) {
413 			error = ioat_bus_dmamap_destroy(ioat, __func__,
414 			    ioat->data_tag, ioat->ring[i].src_dmamap);
415 			if (error != 0)
416 				return (error);
417 		}
418 		for (i = 0; i < 1 << ioat->ring_size_order; i++) {
419 			error = ioat_bus_dmamap_destroy(ioat, __func__,
420 			    ioat->data_tag, ioat->ring[i].dst_dmamap);
421 			if (error != 0)
422 				return (error);
423 		}
424 
425 		for (i = 0; i < 1 << ioat->ring_size_order; i++) {
426 			error = ioat_bus_dmamap_destroy(ioat, __func__,
427 			    ioat->data_tag, ioat->ring[i].src2_dmamap);
428 			if (error != 0)
429 				return (error);
430 		}
431 		for (i = 0; i < 1 << ioat->ring_size_order; i++) {
432 			error = ioat_bus_dmamap_destroy(ioat, __func__,
433 			    ioat->data_tag, ioat->ring[i].dst2_dmamap);
434 			if (error != 0)
435 				return (error);
436 		}
437 
438 		bus_dma_tag_destroy(ioat->data_tag);
439 	}
440 
441 	if (ioat->ring != NULL)
442 		ioat_free_ring(ioat, 1 << ioat->ring_size_order, ioat->ring);
443 
444 	if (ioat->comp_update != NULL) {
445 		bus_dmamap_unload(ioat->comp_update_tag, ioat->comp_update_map);
446 		bus_dmamem_free(ioat->comp_update_tag, ioat->comp_update,
447 		    ioat->comp_update_map);
448 		bus_dma_tag_destroy(ioat->comp_update_tag);
449 	}
450 
451 	if (ioat->hw_desc_ring != NULL) {
452 		bus_dmamap_unload(ioat->hw_desc_tag, ioat->hw_desc_map);
453 		bus_dmamem_free(ioat->hw_desc_tag, ioat->hw_desc_ring,
454 		    ioat->hw_desc_map);
455 		bus_dma_tag_destroy(ioat->hw_desc_tag);
456 	}
457 
458 	return (0);
459 }
460 
461 static int
462 ioat_teardown_intr(struct ioat_softc *ioat)
463 {
464 
465 	if (ioat->tag != NULL)
466 		bus_teardown_intr(ioat->device, ioat->res, ioat->tag);
467 
468 	if (ioat->res != NULL)
469 		bus_release_resource(ioat->device, SYS_RES_IRQ,
470 		    rman_get_rid(ioat->res), ioat->res);
471 
472 	pci_release_msi(ioat->device);
473 	return (0);
474 }
475 
476 static int
477 ioat_start_channel(struct ioat_softc *ioat)
478 {
479 	struct ioat_dma_hw_descriptor *hw_desc;
480 	struct ioat_descriptor *desc;
481 	struct bus_dmadesc *dmadesc;
482 	uint64_t status;
483 	uint32_t chanerr;
484 	int i;
485 
486 	ioat_acquire(&ioat->dmaengine);
487 
488 	/* Submit 'NULL' operation manually to avoid quiescing flag */
489 	desc = ioat_get_ring_entry(ioat, ioat->head);
490 	hw_desc = &ioat_get_descriptor(ioat, ioat->head)->dma;
491 	dmadesc = &desc->bus_dmadesc;
492 
493 	dmadesc->callback_fn = NULL;
494 	dmadesc->callback_arg = NULL;
495 
496 	hw_desc->u.control_raw = 0;
497 	hw_desc->u.control_generic.op = IOAT_OP_COPY;
498 	hw_desc->u.control_generic.completion_update = 1;
499 	hw_desc->size = 8;
500 	hw_desc->src_addr = 0;
501 	hw_desc->dest_addr = 0;
502 	hw_desc->u.control.null = 1;
503 
504 	ioat_submit_single(ioat);
505 	ioat_release(&ioat->dmaengine);
506 
507 	for (i = 0; i < 100; i++) {
508 		DELAY(1);
509 		status = ioat_get_chansts(ioat);
510 		if (is_ioat_idle(status))
511 			return (0);
512 	}
513 
514 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
515 	ioat_log_message(0, "could not start channel: "
516 	    "status = %#jx error = %b\n", (uintmax_t)status, (int)chanerr,
517 	    IOAT_CHANERR_STR);
518 	return (ENXIO);
519 }
520 
521 /*
522  * Initialize Hardware
523  */
524 static int
525 ioat3_attach(device_t device)
526 {
527 	struct ioat_softc *ioat;
528 	struct ioat_descriptor *ring;
529 	struct ioat_dma_hw_descriptor *dma_hw_desc;
530 	void *hw_desc;
531 	bus_addr_t lowaddr;
532 	size_t ringsz;
533 	int i, num_descriptors;
534 	int error;
535 	uint8_t xfercap;
536 
537 	error = 0;
538 	ioat = DEVICE2SOFTC(device);
539 	ioat->capabilities = ioat_read_dmacapability(ioat);
540 
541 	ioat_log_message(0, "Capabilities: %b\n", (int)ioat->capabilities,
542 	    IOAT_DMACAP_STR);
543 
544 	xfercap = ioat_read_xfercap(ioat);
545 	ioat->max_xfer_size = 1 << xfercap;
546 
547 	ioat->intrdelay_supported = (ioat_read_2(ioat, IOAT_INTRDELAY_OFFSET) &
548 	    IOAT_INTRDELAY_SUPPORTED) != 0;
549 	if (ioat->intrdelay_supported)
550 		ioat->intrdelay_max = IOAT_INTRDELAY_US_MASK;
551 
552 	/* TODO: need to check DCA here if we ever do XOR/PQ */
553 
554 	mtx_init(&ioat->submit_lock, "ioat_submit", NULL, MTX_DEF);
555 	mtx_init(&ioat->cleanup_lock, "ioat_cleanup", NULL, MTX_DEF);
556 	callout_init(&ioat->poll_timer, 1);
557 	TASK_INIT(&ioat->reset_task, 0, ioat_reset_hw_task, ioat);
558 
559 	/* Establish lock order for Witness */
560 	mtx_lock(&ioat->cleanup_lock);
561 	mtx_lock(&ioat->submit_lock);
562 	mtx_unlock(&ioat->submit_lock);
563 	mtx_unlock(&ioat->cleanup_lock);
564 
565 	ioat->is_submitter_processing = FALSE;
566 
567 	if (ioat->version >= IOAT_VER_3_3)
568 		lowaddr = BUS_SPACE_MAXADDR_48BIT;
569 	else if (ioat->version >= IOAT_VER_3_2)
570 		lowaddr = BUS_SPACE_MAXADDR_46BIT;
571 	else
572 		lowaddr = BUS_SPACE_MAXADDR_40BIT;
573 
574 	error = bus_dma_tag_create(bus_get_dma_tag(ioat->device),
575 	    sizeof(uint64_t), 0x0, lowaddr, BUS_SPACE_MAXADDR, NULL, NULL,
576 	    sizeof(uint64_t), 1, sizeof(uint64_t), 0, NULL, NULL,
577 	    &ioat->comp_update_tag);
578 	if (error != 0)
579 		return (error);
580 
581 	error = bus_dmamem_alloc(ioat->comp_update_tag,
582 	    (void **)&ioat->comp_update, BUS_DMA_ZERO | BUS_DMA_WAITOK,
583 	    &ioat->comp_update_map);
584 	if (error != 0)
585 		return (error);
586 
587 	error = bus_dmamap_load(ioat->comp_update_tag, ioat->comp_update_map,
588 	    ioat->comp_update, sizeof(uint64_t), ioat_comp_update_map, ioat,
589 	    BUS_DMA_NOWAIT);
590 	if (error != 0)
591 		return (error);
592 
593 	ioat->ring_size_order = g_ioat_ring_order;
594 	num_descriptors = 1 << ioat->ring_size_order;
595 	ringsz = sizeof(struct ioat_dma_hw_descriptor) * num_descriptors;
596 
597 	error = bus_dma_tag_create(bus_get_dma_tag(ioat->device),
598 	    2 * 1024 * 1024, 0x0, lowaddr, BUS_SPACE_MAXADDR, NULL, NULL,
599 	    ringsz, 1, ringsz, 0, NULL, NULL, &ioat->hw_desc_tag);
600 	if (error != 0)
601 		return (error);
602 
603 	error = bus_dmamem_alloc(ioat->hw_desc_tag, &hw_desc,
604 	    BUS_DMA_ZERO | BUS_DMA_WAITOK, &ioat->hw_desc_map);
605 	if (error != 0)
606 		return (error);
607 
608 	error = bus_dmamap_load(ioat->hw_desc_tag, ioat->hw_desc_map, hw_desc,
609 	    ringsz, ioat_dmamap_cb, &ioat->hw_desc_bus_addr, BUS_DMA_NOWAIT);
610 	if (error)
611 		return (error);
612 
613 	ioat->hw_desc_ring = hw_desc;
614 
615 	error = bus_dma_tag_create(bus_get_dma_tag(ioat->device),
616 	    1, 0, lowaddr, BUS_SPACE_MAXADDR, NULL, NULL,
617 	    ioat->max_xfer_size, 1, ioat->max_xfer_size, 0, NULL, NULL,
618 	    &ioat->data_tag);
619 	if (error != 0)
620 		return (error);
621 	ioat->ring = malloc_domainset(num_descriptors * sizeof(*ring), M_IOAT,
622 	    DOMAINSET_PREF(ioat->domain), M_ZERO | M_WAITOK);
623 
624 	ring = ioat->ring;
625 	for (i = 0; i < num_descriptors; i++) {
626 		memset(&ring[i].bus_dmadesc, 0, sizeof(ring[i].bus_dmadesc));
627 		ring[i].id = i;
628 		error = bus_dmamap_create(ioat->data_tag, 0,
629                     &ring[i].src_dmamap);
630 		if (error != 0) {
631 			ioat_log_message(0,
632 			    "%s: bus_dmamap_create failed %d\n", __func__,
633 			    error);
634 			return (error);
635 		}
636 		error = bus_dmamap_create(ioat->data_tag, 0,
637                     &ring[i].dst_dmamap);
638 		if (error != 0) {
639 			ioat_log_message(0,
640 			    "%s: bus_dmamap_create failed %d\n", __func__,
641 			    error);
642 			return (error);
643 		}
644 		error = bus_dmamap_create(ioat->data_tag, 0,
645                     &ring[i].src2_dmamap);
646 		if (error != 0) {
647 			ioat_log_message(0,
648 			    "%s: bus_dmamap_create failed %d\n", __func__,
649 			    error);
650 			return (error);
651 		}
652 		error = bus_dmamap_create(ioat->data_tag, 0,
653                     &ring[i].dst2_dmamap);
654 		if (error != 0) {
655 			ioat_log_message(0,
656 			    "%s: bus_dmamap_create failed %d\n", __func__,
657 			    error);
658 			return (error);
659 		}
660 	}
661 
662 	for (i = 0; i < num_descriptors; i++) {
663 		dma_hw_desc = &ioat->hw_desc_ring[i].dma;
664 		dma_hw_desc->next = RING_PHYS_ADDR(ioat, i + 1);
665 	}
666 
667 	ioat->tail = ioat->head = 0;
668 	*ioat->comp_update = ioat->last_seen =
669 	    RING_PHYS_ADDR(ioat, ioat->tail - 1);
670 	return (0);
671 }
672 
673 static int
674 ioat_map_pci_bar(struct ioat_softc *ioat)
675 {
676 
677 	ioat->pci_resource_id = PCIR_BAR(0);
678 	ioat->pci_resource = bus_alloc_resource_any(ioat->device,
679 	    SYS_RES_MEMORY, &ioat->pci_resource_id, RF_ACTIVE);
680 
681 	if (ioat->pci_resource == NULL) {
682 		ioat_log_message(0, "unable to allocate pci resource\n");
683 		return (ENODEV);
684 	}
685 
686 	ioat->pci_bus_tag = rman_get_bustag(ioat->pci_resource);
687 	ioat->pci_bus_handle = rman_get_bushandle(ioat->pci_resource);
688 	return (0);
689 }
690 
691 static void
692 ioat_comp_update_map(void *arg, bus_dma_segment_t *seg, int nseg, int error)
693 {
694 	struct ioat_softc *ioat = arg;
695 
696 	KASSERT(error == 0, ("%s: error:%d", __func__, error));
697 	ioat->comp_update_bus_addr = seg[0].ds_addr;
698 }
699 
700 static void
701 ioat_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nseg, int error)
702 {
703 	bus_addr_t *baddr;
704 
705 	KASSERT(error == 0, ("%s: error:%d", __func__, error));
706 	baddr = arg;
707 	*baddr = segs->ds_addr;
708 }
709 
710 /*
711  * Interrupt setup and handlers
712  */
713 static int
714 ioat_setup_intr(struct ioat_softc *ioat)
715 {
716 	uint32_t num_vectors;
717 	int error;
718 	boolean_t use_msix;
719 	boolean_t force_legacy_interrupts;
720 
721 	use_msix = FALSE;
722 	force_legacy_interrupts = FALSE;
723 
724 	if (!g_force_legacy_interrupts && pci_msix_count(ioat->device) >= 1) {
725 		num_vectors = 1;
726 		pci_alloc_msix(ioat->device, &num_vectors);
727 		if (num_vectors == 1)
728 			use_msix = TRUE;
729 	}
730 
731 	if (use_msix) {
732 		ioat->rid = 1;
733 		ioat->res = bus_alloc_resource_any(ioat->device, SYS_RES_IRQ,
734 		    &ioat->rid, RF_ACTIVE);
735 	} else {
736 		ioat->rid = 0;
737 		ioat->res = bus_alloc_resource_any(ioat->device, SYS_RES_IRQ,
738 		    &ioat->rid, RF_SHAREABLE | RF_ACTIVE);
739 	}
740 	if (ioat->res == NULL) {
741 		ioat_log_message(0, "bus_alloc_resource failed\n");
742 		return (ENOMEM);
743 	}
744 
745 	ioat->tag = NULL;
746 	error = bus_setup_intr(ioat->device, ioat->res, INTR_MPSAFE |
747 	    INTR_TYPE_MISC, NULL, ioat_interrupt_handler, ioat, &ioat->tag);
748 	if (error != 0) {
749 		ioat_log_message(0, "bus_setup_intr failed\n");
750 		return (error);
751 	}
752 
753 	ioat_write_intrctrl(ioat, IOAT_INTRCTRL_MASTER_INT_EN);
754 	return (0);
755 }
756 
757 static boolean_t
758 ioat_model_resets_msix(struct ioat_softc *ioat)
759 {
760 	u_int32_t pciid;
761 
762 	pciid = pci_get_devid(ioat->device);
763 	switch (pciid) {
764 		/* BWD: */
765 	case 0x0c508086:
766 	case 0x0c518086:
767 	case 0x0c528086:
768 	case 0x0c538086:
769 		/* BDXDE: */
770 	case 0x6f508086:
771 	case 0x6f518086:
772 	case 0x6f528086:
773 	case 0x6f538086:
774 		return (TRUE);
775 	}
776 
777 	return (FALSE);
778 }
779 
780 static void
781 ioat_interrupt_handler(void *arg)
782 {
783 	struct ioat_softc *ioat = arg;
784 
785 	ioat->stats.interrupts++;
786 	ioat_process_events(ioat, TRUE);
787 }
788 
789 static int
790 chanerr_to_errno(uint32_t chanerr)
791 {
792 
793 	if (chanerr == 0)
794 		return (0);
795 	if ((chanerr & (IOAT_CHANERR_XSADDERR | IOAT_CHANERR_XDADDERR)) != 0)
796 		return (EFAULT);
797 	if ((chanerr & (IOAT_CHANERR_RDERR | IOAT_CHANERR_WDERR)) != 0)
798 		return (EIO);
799 	/* This one is probably our fault: */
800 	if ((chanerr & IOAT_CHANERR_NDADDERR) != 0)
801 		return (EIO);
802 	return (EIO);
803 }
804 
805 static void
806 ioat_process_events(struct ioat_softc *ioat, boolean_t intr)
807 {
808 	struct ioat_descriptor *desc;
809 	struct bus_dmadesc *dmadesc;
810 	uint64_t comp_update, status;
811 	uint32_t completed, chanerr;
812 	int error;
813 
814 	if (intr) {
815 		mtx_lock(&ioat->cleanup_lock);
816 	} else {
817 		if (!mtx_trylock(&ioat->cleanup_lock))
818 			return;
819 	}
820 
821 	/*
822 	 * Don't run while the hardware is being reset.  Reset is responsible
823 	 * for blocking new work and draining & completing existing work, so
824 	 * there is nothing to do until new work is queued after reset anyway.
825 	 */
826 	if (ioat->resetting_cleanup) {
827 		mtx_unlock(&ioat->cleanup_lock);
828 		return;
829 	}
830 
831 	completed = 0;
832 	comp_update = *ioat->comp_update;
833 	status = comp_update & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_MASK;
834 
835 	if (status < ioat->hw_desc_bus_addr ||
836 	    status >= ioat->hw_desc_bus_addr + (1 << ioat->ring_size_order) *
837 	    sizeof(struct ioat_generic_hw_descriptor))
838 		panic("Bogus completion address %jx (channel %u)",
839 		    (uintmax_t)status, ioat->chan_idx);
840 
841 	if (status == ioat->last_seen) {
842 		/*
843 		 * If we landed in process_events and nothing has been
844 		 * completed, check for a timeout due to channel halt.
845 		 */
846 		goto out;
847 	}
848 	CTR4(KTR_IOAT, "%s channel=%u hw_status=0x%lx last_seen=0x%lx",
849 	    __func__, ioat->chan_idx, comp_update, ioat->last_seen);
850 
851 	while (RING_PHYS_ADDR(ioat, ioat->tail - 1) != status) {
852 		desc = ioat_get_ring_entry(ioat, ioat->tail);
853 		dmadesc = &desc->bus_dmadesc;
854 		CTR5(KTR_IOAT, "channel=%u completing desc idx %u (%p) ok  cb %p(%p)",
855 		    ioat->chan_idx, ioat->tail, dmadesc, dmadesc->callback_fn,
856 		    dmadesc->callback_arg);
857 
858 		bus_dmamap_unload(ioat->data_tag, desc->src_dmamap);
859 		bus_dmamap_unload(ioat->data_tag, desc->dst_dmamap);
860 		bus_dmamap_unload(ioat->data_tag, desc->src2_dmamap);
861 		bus_dmamap_unload(ioat->data_tag, desc->dst2_dmamap);
862 
863 		if (dmadesc->callback_fn != NULL)
864 			dmadesc->callback_fn(dmadesc->callback_arg, 0);
865 
866 		completed++;
867 		ioat->tail++;
868 	}
869 	CTR5(KTR_IOAT, "%s channel=%u head=%u tail=%u active=%u", __func__,
870 	    ioat->chan_idx, ioat->head, ioat->tail, ioat_get_active(ioat));
871 
872 	if (completed != 0) {
873 		ioat->last_seen = RING_PHYS_ADDR(ioat, ioat->tail - 1);
874 		ioat->stats.descriptors_processed += completed;
875 		wakeup(&ioat->tail);
876 	}
877 
878 out:
879 	ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
880 	mtx_unlock(&ioat->cleanup_lock);
881 
882 	/*
883 	 * The device doesn't seem to reliably push suspend/halt statuses to
884 	 * the channel completion memory address, so poll the device register
885 	 * here.  For performance reasons skip it on interrupts, do it only
886 	 * on much more rare polling events.
887 	 */
888 	if (!intr)
889 		comp_update = ioat_get_chansts(ioat) & IOAT_CHANSTS_STATUS;
890 	if (!is_ioat_halted(comp_update) && !is_ioat_suspended(comp_update))
891 		return;
892 
893 	ioat->stats.channel_halts++;
894 
895 	/*
896 	 * Fatal programming error on this DMA channel.  Flush any outstanding
897 	 * work with error status and restart the engine.
898 	 */
899 	mtx_lock(&ioat->submit_lock);
900 	ioat->quiescing = TRUE;
901 	mtx_unlock(&ioat->submit_lock);
902 
903 	/*
904 	 * This is safe to do here because the submit queue is quiesced.  We
905 	 * know that we will drain all outstanding events, so ioat_reset_hw
906 	 * can't deadlock. It is necessary to protect other ioat_process_event
907 	 * threads from racing ioat_reset_hw, reading an indeterminate hw
908 	 * state, and attempting to continue issuing completions.
909 	 */
910 	mtx_lock(&ioat->cleanup_lock);
911 	ioat->resetting_cleanup = TRUE;
912 
913 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
914 	if (1 <= g_ioat_debug_level)
915 		ioat_halted_debug(ioat, chanerr);
916 	ioat->stats.last_halt_chanerr = chanerr;
917 
918 	while (ioat_get_active(ioat) > 0) {
919 		desc = ioat_get_ring_entry(ioat, ioat->tail);
920 		dmadesc = &desc->bus_dmadesc;
921 		CTR5(KTR_IOAT, "channel=%u completing desc idx %u (%p) err cb %p(%p)",
922 		    ioat->chan_idx, ioat->tail, dmadesc, dmadesc->callback_fn,
923 		    dmadesc->callback_arg);
924 
925 		if (dmadesc->callback_fn != NULL)
926 			dmadesc->callback_fn(dmadesc->callback_arg,
927 			    chanerr_to_errno(chanerr));
928 
929 		ioat->tail++;
930 		ioat->stats.descriptors_processed++;
931 		ioat->stats.descriptors_error++;
932 	}
933 	CTR5(KTR_IOAT, "%s channel=%u head=%u tail=%u active=%u", __func__,
934 	    ioat->chan_idx, ioat->head, ioat->tail, ioat_get_active(ioat));
935 
936 	/* Clear error status */
937 	ioat_write_4(ioat, IOAT_CHANERR_OFFSET, chanerr);
938 
939 	mtx_unlock(&ioat->cleanup_lock);
940 
941 	ioat_log_message(0, "Resetting channel to recover from error\n");
942 	error = taskqueue_enqueue(taskqueue_thread, &ioat->reset_task);
943 	KASSERT(error == 0,
944 	    ("%s: taskqueue_enqueue failed: %d", __func__, error));
945 }
946 
947 static void
948 ioat_reset_hw_task(void *ctx, int pending __unused)
949 {
950 	struct ioat_softc *ioat;
951 	int error;
952 
953 	ioat = ctx;
954 	ioat_log_message(1, "%s: Resetting channel\n", __func__);
955 
956 	error = ioat_reset_hw(ioat);
957 	KASSERT(error == 0, ("%s: reset failed: %d", __func__, error));
958 	(void)error;
959 }
960 
961 /*
962  * User API functions
963  */
964 unsigned
965 ioat_get_nchannels(void)
966 {
967 
968 	return (ioat_channel_index);
969 }
970 
971 bus_dmaengine_t
972 ioat_get_dmaengine(uint32_t index, int flags)
973 {
974 	struct ioat_softc *ioat;
975 
976 	KASSERT((flags & ~(M_NOWAIT | M_WAITOK)) == 0,
977 	    ("invalid flags: 0x%08x", flags));
978 	KASSERT((flags & (M_NOWAIT | M_WAITOK)) != (M_NOWAIT | M_WAITOK),
979 	    ("invalid wait | nowait"));
980 
981 	mtx_lock(&ioat_list_mtx);
982 	if (index >= ioat_channel_index ||
983 	    (ioat = ioat_channel[index]) == NULL) {
984 		mtx_unlock(&ioat_list_mtx);
985 		return (NULL);
986 	}
987 	mtx_lock(&ioat->submit_lock);
988 	mtx_unlock(&ioat_list_mtx);
989 
990 	if (ioat->destroying) {
991 		mtx_unlock(&ioat->submit_lock);
992 		return (NULL);
993 	}
994 
995 	ioat_get(ioat);
996 	if (ioat->quiescing) {
997 		if ((flags & M_NOWAIT) != 0) {
998 			ioat_put(ioat);
999 			mtx_unlock(&ioat->submit_lock);
1000 			return (NULL);
1001 		}
1002 
1003 		while (ioat->quiescing && !ioat->destroying)
1004 			msleep(&ioat->quiescing, &ioat->submit_lock, 0, "getdma", 0);
1005 
1006 		if (ioat->destroying) {
1007 			ioat_put(ioat);
1008 			mtx_unlock(&ioat->submit_lock);
1009 			return (NULL);
1010 		}
1011 	}
1012 	mtx_unlock(&ioat->submit_lock);
1013 	return (&ioat->dmaengine);
1014 }
1015 
1016 void
1017 ioat_put_dmaengine(bus_dmaengine_t dmaengine)
1018 {
1019 	struct ioat_softc *ioat;
1020 
1021 	ioat = to_ioat_softc(dmaengine);
1022 	mtx_lock(&ioat->submit_lock);
1023 	ioat_put(ioat);
1024 	mtx_unlock(&ioat->submit_lock);
1025 }
1026 
1027 int
1028 ioat_get_hwversion(bus_dmaengine_t dmaengine)
1029 {
1030 	struct ioat_softc *ioat;
1031 
1032 	ioat = to_ioat_softc(dmaengine);
1033 	return (ioat->version);
1034 }
1035 
1036 size_t
1037 ioat_get_max_io_size(bus_dmaengine_t dmaengine)
1038 {
1039 	struct ioat_softc *ioat;
1040 
1041 	ioat = to_ioat_softc(dmaengine);
1042 	return (ioat->max_xfer_size);
1043 }
1044 
1045 uint32_t
1046 ioat_get_capabilities(bus_dmaengine_t dmaengine)
1047 {
1048 	struct ioat_softc *ioat;
1049 
1050 	ioat = to_ioat_softc(dmaengine);
1051 	return (ioat->capabilities);
1052 }
1053 
1054 int
1055 ioat_get_domain(bus_dmaengine_t dmaengine, int *domain)
1056 {
1057 	struct ioat_softc *ioat;
1058 
1059 	ioat = to_ioat_softc(dmaengine);
1060 	return (bus_get_domain(ioat->device, domain));
1061 }
1062 
1063 int
1064 ioat_set_interrupt_coalesce(bus_dmaengine_t dmaengine, uint16_t delay)
1065 {
1066 	struct ioat_softc *ioat;
1067 
1068 	ioat = to_ioat_softc(dmaengine);
1069 	if (!ioat->intrdelay_supported)
1070 		return (ENODEV);
1071 	if (delay > ioat->intrdelay_max)
1072 		return (ERANGE);
1073 
1074 	ioat_write_2(ioat, IOAT_INTRDELAY_OFFSET, delay);
1075 	ioat->cached_intrdelay =
1076 	    ioat_read_2(ioat, IOAT_INTRDELAY_OFFSET) & IOAT_INTRDELAY_US_MASK;
1077 	return (0);
1078 }
1079 
1080 uint16_t
1081 ioat_get_max_coalesce_period(bus_dmaengine_t dmaengine)
1082 {
1083 	struct ioat_softc *ioat;
1084 
1085 	ioat = to_ioat_softc(dmaengine);
1086 	return (ioat->intrdelay_max);
1087 }
1088 
1089 void
1090 ioat_acquire(bus_dmaengine_t dmaengine)
1091 {
1092 	struct ioat_softc *ioat;
1093 
1094 	ioat = to_ioat_softc(dmaengine);
1095 	mtx_lock(&ioat->submit_lock);
1096 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1097 	ioat->acq_head = ioat->head;
1098 }
1099 
1100 int
1101 ioat_acquire_reserve(bus_dmaengine_t dmaengine, unsigned n, int mflags)
1102 {
1103 	struct ioat_softc *ioat;
1104 	int error;
1105 
1106 	ioat = to_ioat_softc(dmaengine);
1107 	ioat_acquire(dmaengine);
1108 
1109 	error = ioat_reserve_space(ioat, n, mflags);
1110 	if (error != 0)
1111 		ioat_release(dmaengine);
1112 	return (error);
1113 }
1114 
1115 void
1116 ioat_release(bus_dmaengine_t dmaengine)
1117 {
1118 	struct ioat_softc *ioat;
1119 
1120 	ioat = to_ioat_softc(dmaengine);
1121 	CTR3(KTR_IOAT, "%s channel=%u dispatch1 head=%u", __func__,
1122 	    ioat->chan_idx, ioat->head);
1123 	KFAIL_POINT_CODE(DEBUG_FP, ioat_release, /* do nothing */);
1124 	CTR3(KTR_IOAT, "%s channel=%u dispatch2 head=%u", __func__,
1125 	    ioat->chan_idx, ioat->head);
1126 
1127 	if (ioat->acq_head != ioat->head) {
1128 		ioat_write_2(ioat, IOAT_DMACOUNT_OFFSET,
1129 		    (uint16_t)ioat->head);
1130 
1131 		if (!callout_pending(&ioat->poll_timer)) {
1132 			callout_reset_on(&ioat->poll_timer, 1,
1133 			    ioat_poll_timer_callback, ioat, ioat->cpu);
1134 		}
1135 	}
1136 	mtx_unlock(&ioat->submit_lock);
1137 }
1138 
1139 static struct ioat_descriptor *
1140 ioat_op_generic(struct ioat_softc *ioat, uint8_t op,
1141     uint32_t size, uint64_t src, uint64_t dst,
1142     bus_dmaengine_callback_t callback_fn, void *callback_arg,
1143     uint32_t flags)
1144 {
1145 	struct ioat_generic_hw_descriptor *hw_desc;
1146 	struct ioat_descriptor *desc;
1147 	bus_dma_segment_t seg;
1148 	int mflags, nseg, error;
1149 
1150 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1151 
1152 	KASSERT((flags & ~_DMA_GENERIC_FLAGS) == 0,
1153 	    ("Unrecognized flag(s): %#x", flags & ~_DMA_GENERIC_FLAGS));
1154 	KASSERT(size <= ioat->max_xfer_size, ("%s: size too big (%u > %u)",
1155 	    __func__, (unsigned)size, ioat->max_xfer_size));
1156 
1157 	if ((flags & DMA_NO_WAIT) != 0)
1158 		mflags = M_NOWAIT;
1159 	else
1160 		mflags = M_WAITOK;
1161 
1162 	if (ioat_reserve_space(ioat, 1, mflags) != 0)
1163 		return (NULL);
1164 
1165 	desc = ioat_get_ring_entry(ioat, ioat->head);
1166 	hw_desc = &ioat_get_descriptor(ioat, ioat->head)->generic;
1167 
1168 	hw_desc->u.control_raw = 0;
1169 	hw_desc->u.control_generic.op = op;
1170 	hw_desc->u.control_generic.completion_update = 1;
1171 
1172 	if ((flags & DMA_INT_EN) != 0)
1173 		hw_desc->u.control_generic.int_enable = 1;
1174 	if ((flags & DMA_FENCE) != 0)
1175 		hw_desc->u.control_generic.fence = 1;
1176 
1177 	hw_desc->size = size;
1178 
1179 	if (src != 0) {
1180 		nseg = -1;
1181 		error = _bus_dmamap_load_phys(ioat->data_tag, desc->src_dmamap,
1182 		    src, size, 0, &seg, &nseg);
1183 		if (error != 0) {
1184 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1185 			    " failed %d\n", __func__, error);
1186 			return (NULL);
1187 		}
1188 		hw_desc->src_addr = seg.ds_addr;
1189 	}
1190 
1191 	if (dst != 0) {
1192 		nseg = -1;
1193 		error = _bus_dmamap_load_phys(ioat->data_tag, desc->dst_dmamap,
1194 		    dst, size, 0, &seg, &nseg);
1195 		if (error != 0) {
1196 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1197 			    " failed %d\n", __func__, error);
1198 			return (NULL);
1199 		}
1200 		hw_desc->dest_addr = seg.ds_addr;
1201 	}
1202 
1203 	desc->bus_dmadesc.callback_fn = callback_fn;
1204 	desc->bus_dmadesc.callback_arg = callback_arg;
1205 	return (desc);
1206 }
1207 
1208 struct bus_dmadesc *
1209 ioat_null(bus_dmaengine_t dmaengine, bus_dmaengine_callback_t callback_fn,
1210     void *callback_arg, uint32_t flags)
1211 {
1212 	struct ioat_dma_hw_descriptor *hw_desc;
1213 	struct ioat_descriptor *desc;
1214 	struct ioat_softc *ioat;
1215 
1216 	ioat = to_ioat_softc(dmaengine);
1217 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1218 
1219 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, 8, 0, 0, callback_fn,
1220 	    callback_arg, flags);
1221 	if (desc == NULL)
1222 		return (NULL);
1223 
1224 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->dma;
1225 	hw_desc->u.control.null = 1;
1226 	ioat_submit_single(ioat);
1227 	return (&desc->bus_dmadesc);
1228 }
1229 
1230 struct bus_dmadesc *
1231 ioat_copy(bus_dmaengine_t dmaengine, bus_addr_t dst,
1232     bus_addr_t src, bus_size_t len, bus_dmaengine_callback_t callback_fn,
1233     void *callback_arg, uint32_t flags)
1234 {
1235 	struct ioat_dma_hw_descriptor *hw_desc;
1236 	struct ioat_descriptor *desc;
1237 	struct ioat_softc *ioat;
1238 
1239 	ioat = to_ioat_softc(dmaengine);
1240 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, len, src, dst, callback_fn,
1241 	    callback_arg, flags);
1242 	if (desc == NULL)
1243 		return (NULL);
1244 
1245 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->dma;
1246 	if (g_ioat_debug_level >= 3)
1247 		dump_descriptor(hw_desc);
1248 
1249 	ioat_submit_single(ioat);
1250 	CTR6(KTR_IOAT, "%s channel=%u desc=%p dest=%lx src=%lx len=%lx",
1251 	    __func__, ioat->chan_idx, &desc->bus_dmadesc, dst, src, len);
1252 	return (&desc->bus_dmadesc);
1253 }
1254 
1255 struct bus_dmadesc *
1256 ioat_copy_8k_aligned(bus_dmaengine_t dmaengine, bus_addr_t dst1,
1257     bus_addr_t dst2, bus_addr_t src1, bus_addr_t src2,
1258     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags)
1259 {
1260 	struct ioat_dma_hw_descriptor *hw_desc;
1261 	struct ioat_descriptor *desc;
1262 	struct ioat_softc *ioat;
1263 	bus_size_t src1_len, dst1_len;
1264 	bus_dma_segment_t seg;
1265 	int nseg, error;
1266 
1267 	ioat = to_ioat_softc(dmaengine);
1268 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1269 
1270 	KASSERT(((src1 | src2 | dst1 | dst2) & PAGE_MASK) == 0,
1271 	    ("%s: addresses are not page-aligned", __func__));
1272 
1273 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, 2 * PAGE_SIZE, 0, 0,
1274 	    callback_fn, callback_arg, flags);
1275 	if (desc == NULL)
1276 		return (NULL);
1277 
1278 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->dma;
1279 
1280 	src1_len = (src2 != src1 + PAGE_SIZE) ? PAGE_SIZE : 2 * PAGE_SIZE;
1281 	nseg = -1;
1282 	error = _bus_dmamap_load_phys(ioat->data_tag,
1283 	    desc->src_dmamap, src1, src1_len, 0, &seg, &nseg);
1284 	if (error != 0) {
1285 		ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1286 		    " failed %d\n", __func__, error);
1287 		return (NULL);
1288 	}
1289 	hw_desc->src_addr = seg.ds_addr;
1290 	if (src1_len != 2 * PAGE_SIZE) {
1291 		hw_desc->u.control.src_page_break = 1;
1292 		nseg = -1;
1293 		error = _bus_dmamap_load_phys(ioat->data_tag,
1294 		    desc->src2_dmamap, src2, PAGE_SIZE, 0, &seg, &nseg);
1295 		if (error != 0) {
1296 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1297 			    " failed %d\n", __func__, error);
1298 			return (NULL);
1299 		}
1300 		hw_desc->next_src_addr = seg.ds_addr;
1301 	}
1302 
1303 	dst1_len = (dst2 != dst1 + PAGE_SIZE) ? PAGE_SIZE : 2 * PAGE_SIZE;
1304 	nseg = -1;
1305 	error = _bus_dmamap_load_phys(ioat->data_tag,
1306 	    desc->dst_dmamap, dst1, dst1_len, 0, &seg, &nseg);
1307 	if (error != 0) {
1308 		ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1309 		    " failed %d\n", __func__, error);
1310 		return (NULL);
1311 	}
1312 	hw_desc->dest_addr = seg.ds_addr;
1313 	if (dst1_len != 2 * PAGE_SIZE) {
1314 		hw_desc->u.control.dest_page_break = 1;
1315 		nseg = -1;
1316 		error = _bus_dmamap_load_phys(ioat->data_tag,
1317 		    desc->dst2_dmamap, dst2, PAGE_SIZE, 0, &seg, &nseg);
1318 		if (error != 0) {
1319 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1320 			    " failed %d\n", __func__, error);
1321 			return (NULL);
1322 		}
1323 		hw_desc->next_dest_addr = seg.ds_addr;
1324 	}
1325 
1326 	if (g_ioat_debug_level >= 3)
1327 		dump_descriptor(hw_desc);
1328 
1329 	ioat_submit_single(ioat);
1330 	return (&desc->bus_dmadesc);
1331 }
1332 
1333 struct bus_dmadesc *
1334 ioat_copy_crc(bus_dmaengine_t dmaengine, bus_addr_t dst, bus_addr_t src,
1335     bus_size_t len, uint32_t *initialseed, bus_addr_t crcptr,
1336     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags)
1337 {
1338 	struct ioat_crc32_hw_descriptor *hw_desc;
1339 	struct ioat_descriptor *desc;
1340 	struct ioat_softc *ioat;
1341 	uint32_t teststore;
1342 	uint8_t op;
1343 	bus_dma_segment_t seg;
1344 	int nseg, error;
1345 
1346 	ioat = to_ioat_softc(dmaengine);
1347 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1348 
1349 	KASSERT((ioat->capabilities & IOAT_DMACAP_MOVECRC) != 0,
1350 	    ("%s: device lacks MOVECRC capability", __func__));
1351 	teststore = (flags & _DMA_CRC_TESTSTORE);
1352 	KASSERT(teststore != _DMA_CRC_TESTSTORE,
1353 	    ("%s: TEST and STORE invalid", __func__));
1354 	KASSERT(teststore != 0 || (flags & DMA_CRC_INLINE) == 0,
1355 	    ("%s: INLINE invalid without TEST or STORE", __func__));
1356 
1357 	switch (teststore) {
1358 	case DMA_CRC_STORE:
1359 		op = IOAT_OP_MOVECRC_STORE;
1360 		break;
1361 	case DMA_CRC_TEST:
1362 		op = IOAT_OP_MOVECRC_TEST;
1363 		break;
1364 	default:
1365 		KASSERT(teststore == 0, ("bogus"));
1366 		op = IOAT_OP_MOVECRC;
1367 		break;
1368 	}
1369 
1370 	desc = ioat_op_generic(ioat, op, len, src, dst, callback_fn,
1371 	    callback_arg, flags & ~_DMA_CRC_FLAGS);
1372 	if (desc == NULL)
1373 		return (NULL);
1374 
1375 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->crc32;
1376 
1377 	if ((flags & DMA_CRC_INLINE) == 0) {
1378 		nseg = -1;
1379 		error = _bus_dmamap_load_phys(ioat->data_tag,
1380 		    desc->dst2_dmamap, crcptr, sizeof(uint32_t), 0,
1381 		    &seg, &nseg);
1382 		if (error != 0) {
1383 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1384 			    " failed %d\n", __func__, error);
1385 			return (NULL);
1386 		}
1387 		hw_desc->crc_address = seg.ds_addr;
1388 	} else
1389 		hw_desc->u.control.crc_location = 1;
1390 
1391 	if (initialseed != NULL) {
1392 		hw_desc->u.control.use_seed = 1;
1393 		hw_desc->seed = *initialseed;
1394 	}
1395 
1396 	if (g_ioat_debug_level >= 3)
1397 		dump_descriptor(hw_desc);
1398 
1399 	ioat_submit_single(ioat);
1400 	return (&desc->bus_dmadesc);
1401 }
1402 
1403 struct bus_dmadesc *
1404 ioat_crc(bus_dmaengine_t dmaengine, bus_addr_t src, bus_size_t len,
1405     uint32_t *initialseed, bus_addr_t crcptr,
1406     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags)
1407 {
1408 	struct ioat_crc32_hw_descriptor *hw_desc;
1409 	struct ioat_descriptor *desc;
1410 	struct ioat_softc *ioat;
1411 	uint32_t teststore;
1412 	uint8_t op;
1413 	bus_dma_segment_t seg;
1414 	int nseg, error;
1415 
1416 	ioat = to_ioat_softc(dmaengine);
1417 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1418 
1419 	KASSERT((ioat->capabilities & IOAT_DMACAP_CRC) != 0,
1420 	    ("%s: device lacks CRC capability", __func__));
1421 	teststore = (flags & _DMA_CRC_TESTSTORE);
1422 	KASSERT(teststore != _DMA_CRC_TESTSTORE,
1423 	    ("%s: TEST and STORE invalid", __func__));
1424 	KASSERT(teststore != 0 || (flags & DMA_CRC_INLINE) == 0,
1425 	    ("%s: INLINE invalid without TEST or STORE", __func__));
1426 
1427 	switch (teststore) {
1428 	case DMA_CRC_STORE:
1429 		op = IOAT_OP_CRC_STORE;
1430 		break;
1431 	case DMA_CRC_TEST:
1432 		op = IOAT_OP_CRC_TEST;
1433 		break;
1434 	default:
1435 		KASSERT(teststore == 0, ("bogus"));
1436 		op = IOAT_OP_CRC;
1437 		break;
1438 	}
1439 
1440 	desc = ioat_op_generic(ioat, op, len, src, 0, callback_fn,
1441 	    callback_arg, flags & ~_DMA_CRC_FLAGS);
1442 	if (desc == NULL)
1443 		return (NULL);
1444 
1445 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->crc32;
1446 
1447 	if ((flags & DMA_CRC_INLINE) == 0) {
1448 		nseg = -1;
1449 		error = _bus_dmamap_load_phys(ioat->data_tag,
1450 		    desc->dst2_dmamap, crcptr, sizeof(uint32_t), 0,
1451 		    &seg, &nseg);
1452 		if (error != 0) {
1453 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1454 			    " failed %d\n", __func__, error);
1455 			return (NULL);
1456 		}
1457 		hw_desc->crc_address = seg.ds_addr;
1458 	} else
1459 		hw_desc->u.control.crc_location = 1;
1460 
1461 	if (initialseed != NULL) {
1462 		hw_desc->u.control.use_seed = 1;
1463 		hw_desc->seed = *initialseed;
1464 	}
1465 
1466 	if (g_ioat_debug_level >= 3)
1467 		dump_descriptor(hw_desc);
1468 
1469 	ioat_submit_single(ioat);
1470 	return (&desc->bus_dmadesc);
1471 }
1472 
1473 struct bus_dmadesc *
1474 ioat_blockfill(bus_dmaengine_t dmaengine, bus_addr_t dst, uint64_t fillpattern,
1475     bus_size_t len, bus_dmaengine_callback_t callback_fn, void *callback_arg,
1476     uint32_t flags)
1477 {
1478 	struct ioat_fill_hw_descriptor *hw_desc;
1479 	struct ioat_descriptor *desc;
1480 	struct ioat_softc *ioat;
1481 
1482 	ioat = to_ioat_softc(dmaengine);
1483 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1484 
1485 	KASSERT((ioat->capabilities & IOAT_DMACAP_BFILL) != 0,
1486 	    ("%s: device lacks BFILL capability", __func__));
1487 
1488 	desc = ioat_op_generic(ioat, IOAT_OP_FILL, len, 0, dst,
1489 	    callback_fn, callback_arg, flags);
1490 	if (desc == NULL)
1491 		return (NULL);
1492 
1493 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->fill;
1494 	hw_desc->src_data = fillpattern;
1495 	if (g_ioat_debug_level >= 3)
1496 		dump_descriptor(hw_desc);
1497 
1498 	ioat_submit_single(ioat);
1499 	return (&desc->bus_dmadesc);
1500 }
1501 
1502 /*
1503  * Ring Management
1504  */
1505 static inline uint32_t
1506 ioat_get_active(struct ioat_softc *ioat)
1507 {
1508 
1509 	return ((ioat->head - ioat->tail) & ((1 << ioat->ring_size_order) - 1));
1510 }
1511 
1512 static inline uint32_t
1513 ioat_get_ring_space(struct ioat_softc *ioat)
1514 {
1515 
1516 	return ((1 << ioat->ring_size_order) - ioat_get_active(ioat) - 1);
1517 }
1518 
1519 /*
1520  * Reserves space in this IOAT descriptor ring by ensuring enough slots remain
1521  * for 'num_descs'.
1522  *
1523  * If mflags contains M_WAITOK, blocks until enough space is available.
1524  *
1525  * Returns zero on success, or an errno on error.  If num_descs is beyond the
1526  * maximum ring size, returns EINVAl; if allocation would block and mflags
1527  * contains M_NOWAIT, returns EAGAIN.
1528  *
1529  * Must be called with the submit_lock held; returns with the lock held.  The
1530  * lock may be dropped to allocate the ring.
1531  *
1532  * (The submit_lock is needed to add any entries to the ring, so callers are
1533  * assured enough room is available.)
1534  */
1535 static int
1536 ioat_reserve_space(struct ioat_softc *ioat, uint32_t num_descs, int mflags)
1537 {
1538 	boolean_t dug;
1539 	int error;
1540 
1541 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1542 	error = 0;
1543 	dug = FALSE;
1544 
1545 	if (num_descs < 1 || num_descs >= (1 << ioat->ring_size_order)) {
1546 		error = EINVAL;
1547 		goto out;
1548 	}
1549 
1550 	for (;;) {
1551 		if (ioat->quiescing) {
1552 			error = ENXIO;
1553 			goto out;
1554 		}
1555 
1556 		if (ioat_get_ring_space(ioat) >= num_descs)
1557 			goto out;
1558 
1559 		CTR3(KTR_IOAT, "%s channel=%u starved (%u)", __func__,
1560 		    ioat->chan_idx, num_descs);
1561 
1562 		if (!dug && !ioat->is_submitter_processing) {
1563 			ioat->is_submitter_processing = TRUE;
1564 			mtx_unlock(&ioat->submit_lock);
1565 
1566 			CTR2(KTR_IOAT, "%s channel=%u attempting to process events",
1567 			    __func__, ioat->chan_idx);
1568 			ioat_process_events(ioat, FALSE);
1569 
1570 			mtx_lock(&ioat->submit_lock);
1571 			dug = TRUE;
1572 			KASSERT(ioat->is_submitter_processing == TRUE,
1573 			    ("is_submitter_processing"));
1574 			ioat->is_submitter_processing = FALSE;
1575 			wakeup(&ioat->tail);
1576 			continue;
1577 		}
1578 
1579 		if ((mflags & M_WAITOK) == 0) {
1580 			error = EAGAIN;
1581 			break;
1582 		}
1583 		CTR2(KTR_IOAT, "%s channel=%u blocking on completions",
1584 		    __func__, ioat->chan_idx);
1585 		msleep(&ioat->tail, &ioat->submit_lock, 0,
1586 		    "ioat_full", 0);
1587 		continue;
1588 	}
1589 
1590 out:
1591 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1592 	KASSERT(!ioat->quiescing || error == ENXIO,
1593 	    ("reserved during quiesce"));
1594 	return (error);
1595 }
1596 
1597 static void
1598 ioat_free_ring(struct ioat_softc *ioat, uint32_t size,
1599     struct ioat_descriptor *ring)
1600 {
1601 
1602 	free(ring, M_IOAT);
1603 }
1604 
1605 static struct ioat_descriptor *
1606 ioat_get_ring_entry(struct ioat_softc *ioat, uint32_t index)
1607 {
1608 
1609 	return (&ioat->ring[index % (1 << ioat->ring_size_order)]);
1610 }
1611 
1612 static union ioat_hw_descriptor *
1613 ioat_get_descriptor(struct ioat_softc *ioat, uint32_t index)
1614 {
1615 
1616 	return (&ioat->hw_desc_ring[index % (1 << ioat->ring_size_order)]);
1617 }
1618 
1619 static void
1620 ioat_halted_debug(struct ioat_softc *ioat, uint32_t chanerr)
1621 {
1622 	union ioat_hw_descriptor *desc;
1623 
1624 	ioat_log_message(0, "Channel halted (%b)\n", (int)chanerr,
1625 	    IOAT_CHANERR_STR);
1626 	if (chanerr == 0)
1627 		return;
1628 
1629 	mtx_assert(&ioat->cleanup_lock, MA_OWNED);
1630 
1631 	desc = ioat_get_descriptor(ioat, ioat->tail + 0);
1632 	dump_descriptor(desc);
1633 
1634 	desc = ioat_get_descriptor(ioat, ioat->tail + 1);
1635 	dump_descriptor(desc);
1636 }
1637 
1638 static void
1639 ioat_poll_timer_callback(void *arg)
1640 {
1641 	struct ioat_softc *ioat;
1642 
1643 	ioat = arg;
1644 	CTR1(KTR_IOAT, "%s", __func__);
1645 
1646 	ioat_process_events(ioat, FALSE);
1647 
1648 	mtx_lock(&ioat->submit_lock);
1649 	if (ioat_get_active(ioat) > 0)
1650 		callout_schedule(&ioat->poll_timer, 1);
1651 	mtx_unlock(&ioat->submit_lock);
1652 }
1653 
1654 /*
1655  * Support Functions
1656  */
1657 static void
1658 ioat_submit_single(struct ioat_softc *ioat)
1659 {
1660 
1661 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1662 
1663 	ioat->head++;
1664 	CTR4(KTR_IOAT, "%s channel=%u head=%u tail=%u", __func__,
1665 	    ioat->chan_idx, ioat->head, ioat->tail);
1666 
1667 	ioat->stats.descriptors_submitted++;
1668 }
1669 
1670 static int
1671 ioat_reset_hw(struct ioat_softc *ioat)
1672 {
1673 	uint64_t status;
1674 	uint32_t chanerr;
1675 	unsigned timeout;
1676 	int error;
1677 
1678 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1679 
1680 	mtx_lock(&ioat->submit_lock);
1681 	while (ioat->resetting && !ioat->destroying)
1682 		msleep(&ioat->resetting, &ioat->submit_lock, 0, "IRH_drain", 0);
1683 	if (ioat->destroying) {
1684 		mtx_unlock(&ioat->submit_lock);
1685 		return (ENXIO);
1686 	}
1687 	ioat->resetting = TRUE;
1688 	ioat->quiescing = TRUE;
1689 	mtx_unlock(&ioat->submit_lock);
1690 	mtx_lock(&ioat->cleanup_lock);
1691 	while (ioat_get_active(ioat) > 0)
1692 		msleep(&ioat->tail, &ioat->cleanup_lock, 0, "ioat_drain", 1);
1693 
1694 	/*
1695 	 * Suspend ioat_process_events while the hardware and softc are in an
1696 	 * indeterminate state.
1697 	 */
1698 	ioat->resetting_cleanup = TRUE;
1699 	mtx_unlock(&ioat->cleanup_lock);
1700 
1701 	CTR2(KTR_IOAT, "%s channel=%u quiesced and drained", __func__,
1702 	    ioat->chan_idx);
1703 
1704 	status = ioat_get_chansts(ioat);
1705 	if (is_ioat_active(status) || is_ioat_idle(status))
1706 		ioat_suspend(ioat);
1707 
1708 	/* Wait at most 20 ms */
1709 	for (timeout = 0; (is_ioat_active(status) || is_ioat_idle(status)) &&
1710 	    timeout < 20; timeout++) {
1711 		DELAY(1000);
1712 		status = ioat_get_chansts(ioat);
1713 	}
1714 	if (timeout == 20) {
1715 		error = ETIMEDOUT;
1716 		goto out;
1717 	}
1718 
1719 	KASSERT(ioat_get_active(ioat) == 0, ("active after quiesce"));
1720 
1721 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
1722 	ioat_write_4(ioat, IOAT_CHANERR_OFFSET, chanerr);
1723 
1724 	CTR2(KTR_IOAT, "%s channel=%u hardware suspended", __func__,
1725 	    ioat->chan_idx);
1726 
1727 	/*
1728 	 * IOAT v3 workaround - CHANERRMSK_INT with 3E07h to masks out errors
1729 	 *  that can cause stability issues for IOAT v3.
1730 	 */
1731 	pci_write_config(ioat->device, IOAT_CFG_CHANERRMASK_INT_OFFSET, 0x3e07,
1732 	    4);
1733 	chanerr = pci_read_config(ioat->device, IOAT_CFG_CHANERR_INT_OFFSET, 4);
1734 	pci_write_config(ioat->device, IOAT_CFG_CHANERR_INT_OFFSET, chanerr, 4);
1735 
1736 	/*
1737 	 * BDXDE and BWD models reset MSI-X registers on device reset.
1738 	 * Save/restore their contents manually.
1739 	 */
1740 	if (ioat_model_resets_msix(ioat)) {
1741 		ioat_log_message(1, "device resets MSI-X registers; saving\n");
1742 		pci_save_state(ioat->device);
1743 	}
1744 
1745 	ioat_reset(ioat);
1746 	CTR2(KTR_IOAT, "%s channel=%u hardware reset", __func__,
1747 	    ioat->chan_idx);
1748 
1749 	/* Wait at most 20 ms */
1750 	for (timeout = 0; ioat_reset_pending(ioat) && timeout < 20; timeout++)
1751 		DELAY(1000);
1752 	if (timeout == 20) {
1753 		error = ETIMEDOUT;
1754 		goto out;
1755 	}
1756 
1757 	if (ioat_model_resets_msix(ioat)) {
1758 		ioat_log_message(1, "device resets registers; restored\n");
1759 		pci_restore_state(ioat->device);
1760 	}
1761 
1762 	/* Reset attempts to return the hardware to "halted." */
1763 	status = ioat_get_chansts(ioat);
1764 	if (is_ioat_active(status) || is_ioat_idle(status)) {
1765 		/* So this really shouldn't happen... */
1766 		ioat_log_message(0, "Device is active after a reset?\n");
1767 		ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
1768 		error = 0;
1769 		goto out;
1770 	}
1771 
1772 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
1773 	if (chanerr != 0) {
1774 		mtx_lock(&ioat->cleanup_lock);
1775 		ioat_halted_debug(ioat, chanerr);
1776 		mtx_unlock(&ioat->cleanup_lock);
1777 		error = EIO;
1778 		goto out;
1779 	}
1780 
1781 	/*
1782 	 * Bring device back online after reset.  Writing CHAINADDR brings the
1783 	 * device back to active.
1784 	 *
1785 	 * The internal ring counter resets to zero, so we have to start over
1786 	 * at zero as well.
1787 	 */
1788 	ioat->tail = ioat->head = 0;
1789 	*ioat->comp_update = ioat->last_seen =
1790 	    RING_PHYS_ADDR(ioat, ioat->tail - 1);
1791 
1792 	ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
1793 	ioat_write_chancmp(ioat, ioat->comp_update_bus_addr);
1794 	ioat_write_chainaddr(ioat, RING_PHYS_ADDR(ioat, 0));
1795 	error = 0;
1796 	CTR2(KTR_IOAT, "%s channel=%u configured channel", __func__,
1797 	    ioat->chan_idx);
1798 
1799 out:
1800 	/* Enqueues a null operation and ensures it completes. */
1801 	if (error == 0) {
1802 		error = ioat_start_channel(ioat);
1803 		CTR2(KTR_IOAT, "%s channel=%u started channel", __func__,
1804 		    ioat->chan_idx);
1805 	}
1806 
1807 	/*
1808 	 * Resume completions now that ring state is consistent.
1809 	 */
1810 	mtx_lock(&ioat->cleanup_lock);
1811 	ioat->resetting_cleanup = FALSE;
1812 	mtx_unlock(&ioat->cleanup_lock);
1813 
1814 	/* Unblock submission of new work */
1815 	mtx_lock(&ioat->submit_lock);
1816 	ioat->quiescing = FALSE;
1817 	wakeup(&ioat->quiescing);
1818 
1819 	ioat->resetting = FALSE;
1820 	wakeup(&ioat->resetting);
1821 
1822 	CTR2(KTR_IOAT, "%s channel=%u reset done", __func__, ioat->chan_idx);
1823 	mtx_unlock(&ioat->submit_lock);
1824 
1825 	return (error);
1826 }
1827 
1828 static int
1829 sysctl_handle_chansts(SYSCTL_HANDLER_ARGS)
1830 {
1831 	struct ioat_softc *ioat;
1832 	struct sbuf sb;
1833 	uint64_t status;
1834 	int error;
1835 
1836 	ioat = arg1;
1837 
1838 	status = ioat_get_chansts(ioat) & IOAT_CHANSTS_STATUS;
1839 
1840 	sbuf_new_for_sysctl(&sb, NULL, 256, req);
1841 	switch (status) {
1842 	case IOAT_CHANSTS_ACTIVE:
1843 		sbuf_printf(&sb, "ACTIVE");
1844 		break;
1845 	case IOAT_CHANSTS_IDLE:
1846 		sbuf_printf(&sb, "IDLE");
1847 		break;
1848 	case IOAT_CHANSTS_SUSPENDED:
1849 		sbuf_printf(&sb, "SUSPENDED");
1850 		break;
1851 	case IOAT_CHANSTS_HALTED:
1852 		sbuf_printf(&sb, "HALTED");
1853 		break;
1854 	case IOAT_CHANSTS_ARMED:
1855 		sbuf_printf(&sb, "ARMED");
1856 		break;
1857 	default:
1858 		sbuf_printf(&sb, "UNKNOWN");
1859 		break;
1860 	}
1861 	error = sbuf_finish(&sb);
1862 	sbuf_delete(&sb);
1863 
1864 	if (error != 0 || req->newptr == NULL)
1865 		return (error);
1866 	return (EINVAL);
1867 }
1868 
1869 static int
1870 sysctl_handle_dpi(SYSCTL_HANDLER_ARGS)
1871 {
1872 	struct ioat_softc *ioat;
1873 	struct sbuf sb;
1874 #define	PRECISION	"1"
1875 	const uintmax_t factor = 10;
1876 	uintmax_t rate;
1877 	int error;
1878 
1879 	ioat = arg1;
1880 	sbuf_new_for_sysctl(&sb, NULL, 16, req);
1881 
1882 	if (ioat->stats.interrupts == 0) {
1883 		sbuf_printf(&sb, "NaN");
1884 		goto out;
1885 	}
1886 	rate = ioat->stats.descriptors_processed * factor /
1887 	    ioat->stats.interrupts;
1888 	sbuf_printf(&sb, "%ju.%." PRECISION "ju", rate / factor,
1889 	    rate % factor);
1890 #undef	PRECISION
1891 out:
1892 	error = sbuf_finish(&sb);
1893 	sbuf_delete(&sb);
1894 	if (error != 0 || req->newptr == NULL)
1895 		return (error);
1896 	return (EINVAL);
1897 }
1898 
1899 static int
1900 sysctl_handle_reset(SYSCTL_HANDLER_ARGS)
1901 {
1902 	struct ioat_softc *ioat;
1903 	int error, arg;
1904 
1905 	ioat = arg1;
1906 
1907 	arg = 0;
1908 	error = SYSCTL_OUT(req, &arg, sizeof(arg));
1909 	if (error != 0 || req->newptr == NULL)
1910 		return (error);
1911 
1912 	error = SYSCTL_IN(req, &arg, sizeof(arg));
1913 	if (error != 0)
1914 		return (error);
1915 
1916 	if (arg != 0)
1917 		error = ioat_reset_hw(ioat);
1918 
1919 	return (error);
1920 }
1921 
1922 static void
1923 dump_descriptor(void *hw_desc)
1924 {
1925 	int i, j;
1926 
1927 	for (i = 0; i < 2; i++) {
1928 		for (j = 0; j < 8; j++)
1929 			printf("%08x ", ((uint32_t *)hw_desc)[i * 8 + j]);
1930 		printf("\n");
1931 	}
1932 }
1933 
1934 static void
1935 ioat_setup_sysctl(device_t device)
1936 {
1937 	struct sysctl_oid_list *par, *statpar, *state, *hammer;
1938 	struct sysctl_ctx_list *ctx;
1939 	struct sysctl_oid *tree, *tmp;
1940 	struct ioat_softc *ioat;
1941 
1942 	ioat = DEVICE2SOFTC(device);
1943 	ctx = device_get_sysctl_ctx(device);
1944 	tree = device_get_sysctl_tree(device);
1945 	par = SYSCTL_CHILDREN(tree);
1946 
1947 	SYSCTL_ADD_INT(ctx, par, OID_AUTO, "version", CTLFLAG_RD,
1948 	    &ioat->version, 0, "HW version (0xMM form)");
1949 	SYSCTL_ADD_UINT(ctx, par, OID_AUTO, "max_xfer_size", CTLFLAG_RD,
1950 	    &ioat->max_xfer_size, 0, "HW maximum transfer size");
1951 	SYSCTL_ADD_INT(ctx, par, OID_AUTO, "intrdelay_supported", CTLFLAG_RD,
1952 	    &ioat->intrdelay_supported, 0, "Is INTRDELAY supported");
1953 	SYSCTL_ADD_U16(ctx, par, OID_AUTO, "intrdelay_max", CTLFLAG_RD,
1954 	    &ioat->intrdelay_max, 0,
1955 	    "Maximum configurable INTRDELAY on this channel (microseconds)");
1956 
1957 	tmp = SYSCTL_ADD_NODE(ctx, par, OID_AUTO, "state",
1958 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "IOAT channel internal state");
1959 	state = SYSCTL_CHILDREN(tmp);
1960 
1961 	SYSCTL_ADD_UINT(ctx, state, OID_AUTO, "ring_size_order", CTLFLAG_RD,
1962 	    &ioat->ring_size_order, 0, "SW descriptor ring size order");
1963 	SYSCTL_ADD_UINT(ctx, state, OID_AUTO, "head", CTLFLAG_RD, &ioat->head,
1964 	    0, "SW descriptor head pointer index");
1965 	SYSCTL_ADD_UINT(ctx, state, OID_AUTO, "tail", CTLFLAG_RD, &ioat->tail,
1966 	    0, "SW descriptor tail pointer index");
1967 
1968 	SYSCTL_ADD_UQUAD(ctx, state, OID_AUTO, "last_completion", CTLFLAG_RD,
1969 	    ioat->comp_update, "HW addr of last completion");
1970 
1971 	SYSCTL_ADD_INT(ctx, state, OID_AUTO, "is_submitter_processing",
1972 	    CTLFLAG_RD, &ioat->is_submitter_processing, 0,
1973 	    "submitter processing");
1974 
1975 	SYSCTL_ADD_PROC(ctx, state, OID_AUTO, "chansts",
1976 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, ioat, 0,
1977 	    sysctl_handle_chansts, "A", "String of the channel status");
1978 
1979 	SYSCTL_ADD_U16(ctx, state, OID_AUTO, "intrdelay", CTLFLAG_RD,
1980 	    &ioat->cached_intrdelay, 0,
1981 	    "Current INTRDELAY on this channel (cached, microseconds)");
1982 
1983 	tmp = SYSCTL_ADD_NODE(ctx, par, OID_AUTO, "hammer",
1984 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
1985 	    "Big hammers (mostly for testing)");
1986 	hammer = SYSCTL_CHILDREN(tmp);
1987 
1988 	SYSCTL_ADD_PROC(ctx, hammer, OID_AUTO, "force_hw_reset",
1989 	    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, ioat, 0,
1990 	    sysctl_handle_reset, "I", "Set to non-zero to reset the hardware");
1991 
1992 	tmp = SYSCTL_ADD_NODE(ctx, par, OID_AUTO, "stats",
1993 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "IOAT channel statistics");
1994 	statpar = SYSCTL_CHILDREN(tmp);
1995 
1996 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "interrupts",
1997 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.interrupts,
1998 	    "Number of interrupts processed on this channel");
1999 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "descriptors",
2000 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.descriptors_processed,
2001 	    "Number of descriptors processed on this channel");
2002 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "submitted",
2003 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.descriptors_submitted,
2004 	    "Number of descriptors submitted to this channel");
2005 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "errored",
2006 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.descriptors_error,
2007 	    "Number of descriptors failed by channel errors");
2008 	SYSCTL_ADD_U32(ctx, statpar, OID_AUTO, "halts",
2009 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.channel_halts, 0,
2010 	    "Number of times the channel has halted");
2011 	SYSCTL_ADD_U32(ctx, statpar, OID_AUTO, "last_halt_chanerr",
2012 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.last_halt_chanerr, 0,
2013 	    "The raw CHANERR when the channel was last halted");
2014 
2015 	SYSCTL_ADD_PROC(ctx, statpar, OID_AUTO, "desc_per_interrupt",
2016 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, ioat, 0,
2017 	    sysctl_handle_dpi, "A", "Descriptors per interrupt");
2018 }
2019 
2020 static void
2021 ioat_get(struct ioat_softc *ioat)
2022 {
2023 
2024 	mtx_assert(&ioat->submit_lock, MA_OWNED);
2025 	KASSERT(ioat->refcnt < UINT32_MAX, ("refcnt overflow"));
2026 
2027 	ioat->refcnt++;
2028 }
2029 
2030 static void
2031 ioat_put(struct ioat_softc *ioat)
2032 {
2033 
2034 	mtx_assert(&ioat->submit_lock, MA_OWNED);
2035 	KASSERT(ioat->refcnt >= 1, ("refcnt error"));
2036 
2037 	if (--ioat->refcnt == 0)
2038 		wakeup(&ioat->refcnt);
2039 }
2040 
2041 static void
2042 ioat_drain_locked(struct ioat_softc *ioat)
2043 {
2044 
2045 	mtx_assert(&ioat->submit_lock, MA_OWNED);
2046 
2047 	while (ioat->refcnt > 0)
2048 		msleep(&ioat->refcnt, &ioat->submit_lock, 0, "ioat_drain", 0);
2049 }
2050 
2051 #ifdef DDB
2052 #define	_db_show_lock(lo)	LOCK_CLASS(lo)->lc_ddb_show(lo)
2053 #define	db_show_lock(lk)	_db_show_lock(&(lk)->lock_object)
2054 DB_SHOW_COMMAND(ioat, db_show_ioat)
2055 {
2056 	struct ioat_softc *sc;
2057 	unsigned idx;
2058 
2059 	if (!have_addr)
2060 		goto usage;
2061 	idx = (unsigned)addr;
2062 	if (idx >= ioat_channel_index)
2063 		goto usage;
2064 
2065 	sc = ioat_channel[idx];
2066 	db_printf("ioat softc at %p\n", sc);
2067 	if (sc == NULL)
2068 		return;
2069 
2070 	db_printf(" version: %d\n", sc->version);
2071 	db_printf(" chan_idx: %u\n", sc->chan_idx);
2072 	db_printf(" submit_lock: ");
2073 	db_show_lock(&sc->submit_lock);
2074 
2075 	db_printf(" capabilities: %b\n", (int)sc->capabilities,
2076 	    IOAT_DMACAP_STR);
2077 	db_printf(" cached_intrdelay: %u\n", sc->cached_intrdelay);
2078 	db_printf(" *comp_update: 0x%jx\n", (uintmax_t)*sc->comp_update);
2079 
2080 	db_printf(" poll_timer:\n");
2081 	db_printf("  c_time: %ju\n", (uintmax_t)sc->poll_timer.c_time);
2082 	db_printf("  c_arg: %p\n", sc->poll_timer.c_arg);
2083 	db_printf("  c_func: %p\n", sc->poll_timer.c_func);
2084 	db_printf("  c_lock: %p\n", sc->poll_timer.c_lock);
2085 	db_printf("  c_flags: 0x%x\n", (unsigned)sc->poll_timer.c_flags);
2086 
2087 	db_printf(" quiescing: %d\n", (int)sc->quiescing);
2088 	db_printf(" destroying: %d\n", (int)sc->destroying);
2089 	db_printf(" is_submitter_processing: %d\n",
2090 	    (int)sc->is_submitter_processing);
2091 	db_printf(" intrdelay_supported: %d\n", (int)sc->intrdelay_supported);
2092 	db_printf(" resetting: %d\n", (int)sc->resetting);
2093 
2094 	db_printf(" head: %u\n", sc->head);
2095 	db_printf(" tail: %u\n", sc->tail);
2096 	db_printf(" ring_size_order: %u\n", sc->ring_size_order);
2097 	db_printf(" last_seen: 0x%lx\n", sc->last_seen);
2098 	db_printf(" ring: %p\n", sc->ring);
2099 	db_printf(" descriptors: %p\n", sc->hw_desc_ring);
2100 	db_printf(" descriptors (phys): 0x%jx\n",
2101 	    (uintmax_t)sc->hw_desc_bus_addr);
2102 
2103 	db_printf("  ring[%u] (tail):\n", sc->tail %
2104 	    (1 << sc->ring_size_order));
2105 	db_printf("   id: %u\n", ioat_get_ring_entry(sc, sc->tail)->id);
2106 	db_printf("   addr: 0x%lx\n",
2107 	    RING_PHYS_ADDR(sc, sc->tail));
2108 	db_printf("   next: 0x%lx\n",
2109 	     ioat_get_descriptor(sc, sc->tail)->generic.next);
2110 
2111 	db_printf("  ring[%u] (head - 1):\n", (sc->head - 1) %
2112 	    (1 << sc->ring_size_order));
2113 	db_printf("   id: %u\n", ioat_get_ring_entry(sc, sc->head - 1)->id);
2114 	db_printf("   addr: 0x%lx\n",
2115 	    RING_PHYS_ADDR(sc, sc->head - 1));
2116 	db_printf("   next: 0x%lx\n",
2117 	     ioat_get_descriptor(sc, sc->head - 1)->generic.next);
2118 
2119 	db_printf("  ring[%u] (head):\n", (sc->head) %
2120 	    (1 << sc->ring_size_order));
2121 	db_printf("   id: %u\n", ioat_get_ring_entry(sc, sc->head)->id);
2122 	db_printf("   addr: 0x%lx\n",
2123 	    RING_PHYS_ADDR(sc, sc->head));
2124 	db_printf("   next: 0x%lx\n",
2125 	     ioat_get_descriptor(sc, sc->head)->generic.next);
2126 
2127 	for (idx = 0; idx < (1 << sc->ring_size_order); idx++)
2128 		if ((*sc->comp_update & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_MASK)
2129 		    == RING_PHYS_ADDR(sc, idx))
2130 			db_printf("  ring[%u] == hardware tail\n", idx);
2131 
2132 	db_printf(" cleanup_lock: ");
2133 	db_show_lock(&sc->cleanup_lock);
2134 
2135 	db_printf(" refcnt: %u\n", sc->refcnt);
2136 	db_printf(" stats:\n");
2137 	db_printf("  interrupts: %lu\n", sc->stats.interrupts);
2138 	db_printf("  descriptors_processed: %lu\n", sc->stats.descriptors_processed);
2139 	db_printf("  descriptors_error: %lu\n", sc->stats.descriptors_error);
2140 	db_printf("  descriptors_submitted: %lu\n", sc->stats.descriptors_submitted);
2141 
2142 	db_printf("  channel_halts: %u\n", sc->stats.channel_halts);
2143 	db_printf("  last_halt_chanerr: %u\n", sc->stats.last_halt_chanerr);
2144 
2145 	if (db_pager_quit)
2146 		return;
2147 
2148 	db_printf(" hw status:\n");
2149 	db_printf("  status: 0x%lx\n", ioat_get_chansts(sc));
2150 	db_printf("  chanctrl: 0x%x\n",
2151 	    (unsigned)ioat_read_2(sc, IOAT_CHANCTRL_OFFSET));
2152 	db_printf("  chancmd: 0x%x\n",
2153 	    (unsigned)ioat_read_1(sc, IOAT_CHANCMD_OFFSET));
2154 	db_printf("  dmacount: 0x%x\n",
2155 	    (unsigned)ioat_read_2(sc, IOAT_DMACOUNT_OFFSET));
2156 	db_printf("  chainaddr: 0x%lx\n",
2157 	    ioat_read_double_4(sc, IOAT_CHAINADDR_OFFSET_LOW));
2158 	db_printf("  chancmp: 0x%lx\n",
2159 	    ioat_read_double_4(sc, IOAT_CHANCMP_OFFSET_LOW));
2160 	db_printf("  chanerr: %b\n",
2161 	    (int)ioat_read_4(sc, IOAT_CHANERR_OFFSET), IOAT_CHANERR_STR);
2162 	return;
2163 usage:
2164 	db_printf("usage: show ioat <0-%u>\n", ioat_channel_index);
2165 	return;
2166 }
2167 #endif /* DDB */
2168