xref: /freebsd/sys/dev/ioat/ioat.c (revision ebacd8013fe5f7fdf9f6a5b286f6680dd2891036)
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 	{ 0x0b008086, "ICX IOAT" },
245 };
246 
247 MODULE_PNP_INFO("W32:vendor/device;D:#", pci, ioat, pci_ids,
248     nitems(pci_ids));
249 
250 /*
251  * OS <-> Driver linkage functions
252  */
253 static int
254 ioat_modevent(module_t mod __unused, int type, void *data __unused)
255 {
256 	switch(type) {
257 	case MOD_LOAD:
258 		break;
259 
260 	case MOD_UNLOAD:
261 		ioat_test_detach();
262 		break;
263 
264 	case MOD_SHUTDOWN:
265 		break;
266 
267 	default:
268 		return (EOPNOTSUPP);
269 	}
270 
271 	return (0);
272 }
273 
274 static int
275 ioat_probe(device_t device)
276 {
277 	struct _pcsid *ep;
278 	u_int32_t type;
279 
280 	type = pci_get_devid(device);
281 	for (ep = pci_ids; ep < &pci_ids[nitems(pci_ids)]; ep++) {
282 		if (ep->type == type) {
283 			device_set_desc(device, ep->desc);
284 			return (0);
285 		}
286 	}
287 	return (ENXIO);
288 }
289 
290 static int
291 ioat_attach(device_t device)
292 {
293 	struct ioat_softc *ioat;
294 	int error, i;
295 
296 	ioat = DEVICE2SOFTC(device);
297 	ioat->device = device;
298 	if (bus_get_domain(device, &ioat->domain) != 0)
299 		ioat->domain = 0;
300 	ioat->cpu = CPU_FFS(&cpuset_domain[ioat->domain]) - 1;
301 	if (ioat->cpu < 0)
302 		ioat->cpu = CPU_FIRST();
303 
304 	error = ioat_map_pci_bar(ioat);
305 	if (error != 0)
306 		goto err;
307 
308 	ioat->version = ioat_read_cbver(ioat);
309 	if (ioat->version < IOAT_VER_3_0) {
310 		error = ENODEV;
311 		goto err;
312 	}
313 
314 	error = ioat3_attach(device);
315 	if (error != 0)
316 		goto err;
317 
318 	error = pci_enable_busmaster(device);
319 	if (error != 0)
320 		goto err;
321 
322 	error = ioat_setup_intr(ioat);
323 	if (error != 0)
324 		goto err;
325 
326 	error = ioat_reset_hw(ioat);
327 	if (error != 0)
328 		goto err;
329 
330 	ioat_process_events(ioat, FALSE);
331 	ioat_setup_sysctl(device);
332 
333 	mtx_lock(&ioat_list_mtx);
334 	for (i = 0; i < IOAT_MAX_CHANNELS; i++) {
335 		if (ioat_channel[i] == NULL)
336 			break;
337 	}
338 	if (i >= IOAT_MAX_CHANNELS) {
339 		mtx_unlock(&ioat_list_mtx);
340 		device_printf(device, "Too many I/OAT devices in system\n");
341 		error = ENXIO;
342 		goto err;
343 	}
344 	ioat->chan_idx = i;
345 	ioat_channel[i] = ioat;
346 	if (i >= ioat_channel_index)
347 		ioat_channel_index = i + 1;
348 	mtx_unlock(&ioat_list_mtx);
349 
350 	ioat_test_attach();
351 
352 err:
353 	if (error != 0)
354 		ioat_detach(device);
355 	return (error);
356 }
357 
358 static inline int
359 ioat_bus_dmamap_destroy(struct ioat_softc *ioat, const char *func,
360     bus_dma_tag_t dmat, bus_dmamap_t map)
361 {
362 	int error;
363 
364 	error = bus_dmamap_destroy(dmat, map);
365 	if (error != 0) {
366 		ioat_log_message(0,
367 		    "%s: bus_dmamap_destroy failed %d\n", func, error);
368 	}
369 
370 	return (error);
371 }
372 
373 static int
374 ioat_detach(device_t device)
375 {
376 	struct ioat_softc *ioat;
377 	int i, error;
378 
379 	ioat = DEVICE2SOFTC(device);
380 
381 	mtx_lock(&ioat_list_mtx);
382 	ioat_channel[ioat->chan_idx] = NULL;
383 	while (ioat_channel_index > 0 &&
384 	    ioat_channel[ioat_channel_index - 1] == NULL)
385 		ioat_channel_index--;
386 	mtx_unlock(&ioat_list_mtx);
387 
388 	taskqueue_drain(taskqueue_thread, &ioat->reset_task);
389 
390 	mtx_lock(&ioat->submit_lock);
391 	ioat->quiescing = TRUE;
392 	ioat->destroying = TRUE;
393 	wakeup(&ioat->quiescing);
394 	wakeup(&ioat->resetting);
395 
396 	ioat_drain_locked(ioat);
397 	mtx_unlock(&ioat->submit_lock);
398 	mtx_lock(&ioat->cleanup_lock);
399 	while (ioat_get_active(ioat) > 0)
400 		msleep(&ioat->tail, &ioat->cleanup_lock, 0, "ioat_drain", 1);
401 	mtx_unlock(&ioat->cleanup_lock);
402 
403 	ioat_teardown_intr(ioat);
404 	callout_drain(&ioat->poll_timer);
405 
406 	pci_disable_busmaster(device);
407 
408 	if (ioat->pci_resource != NULL)
409 		bus_release_resource(device, SYS_RES_MEMORY,
410 		    ioat->pci_resource_id, ioat->pci_resource);
411 
412 	if (ioat->data_tag != NULL) {
413 		for (i = 0; i < 1 << ioat->ring_size_order; i++) {
414 			error = ioat_bus_dmamap_destroy(ioat, __func__,
415 			    ioat->data_tag, ioat->ring[i].src_dmamap);
416 			if (error != 0)
417 				return (error);
418 		}
419 		for (i = 0; i < 1 << ioat->ring_size_order; i++) {
420 			error = ioat_bus_dmamap_destroy(ioat, __func__,
421 			    ioat->data_tag, ioat->ring[i].dst_dmamap);
422 			if (error != 0)
423 				return (error);
424 		}
425 
426 		for (i = 0; i < 1 << ioat->ring_size_order; i++) {
427 			error = ioat_bus_dmamap_destroy(ioat, __func__,
428 			    ioat->data_tag, ioat->ring[i].src2_dmamap);
429 			if (error != 0)
430 				return (error);
431 		}
432 		for (i = 0; i < 1 << ioat->ring_size_order; i++) {
433 			error = ioat_bus_dmamap_destroy(ioat, __func__,
434 			    ioat->data_tag, ioat->ring[i].dst2_dmamap);
435 			if (error != 0)
436 				return (error);
437 		}
438 
439 		bus_dma_tag_destroy(ioat->data_tag);
440 	}
441 
442 	if (ioat->ring != NULL)
443 		ioat_free_ring(ioat, 1 << ioat->ring_size_order, ioat->ring);
444 
445 	if (ioat->comp_update != NULL) {
446 		bus_dmamap_unload(ioat->comp_update_tag, ioat->comp_update_map);
447 		bus_dmamem_free(ioat->comp_update_tag, ioat->comp_update,
448 		    ioat->comp_update_map);
449 		bus_dma_tag_destroy(ioat->comp_update_tag);
450 	}
451 
452 	if (ioat->hw_desc_ring != NULL) {
453 		bus_dmamap_unload(ioat->hw_desc_tag, ioat->hw_desc_map);
454 		bus_dmamem_free(ioat->hw_desc_tag, ioat->hw_desc_ring,
455 		    ioat->hw_desc_map);
456 		bus_dma_tag_destroy(ioat->hw_desc_tag);
457 	}
458 
459 	return (0);
460 }
461 
462 static int
463 ioat_teardown_intr(struct ioat_softc *ioat)
464 {
465 
466 	if (ioat->tag != NULL)
467 		bus_teardown_intr(ioat->device, ioat->res, ioat->tag);
468 
469 	if (ioat->res != NULL)
470 		bus_release_resource(ioat->device, SYS_RES_IRQ,
471 		    rman_get_rid(ioat->res), ioat->res);
472 
473 	pci_release_msi(ioat->device);
474 	return (0);
475 }
476 
477 static int
478 ioat_start_channel(struct ioat_softc *ioat)
479 {
480 	struct ioat_dma_hw_descriptor *hw_desc;
481 	struct ioat_descriptor *desc;
482 	struct bus_dmadesc *dmadesc;
483 	uint64_t status;
484 	uint32_t chanerr;
485 	int i;
486 
487 	ioat_acquire(&ioat->dmaengine);
488 
489 	/* Submit 'NULL' operation manually to avoid quiescing flag */
490 	desc = ioat_get_ring_entry(ioat, ioat->head);
491 	hw_desc = &ioat_get_descriptor(ioat, ioat->head)->dma;
492 	dmadesc = &desc->bus_dmadesc;
493 
494 	dmadesc->callback_fn = NULL;
495 	dmadesc->callback_arg = NULL;
496 
497 	hw_desc->u.control_raw = 0;
498 	hw_desc->u.control_generic.op = IOAT_OP_COPY;
499 	hw_desc->u.control_generic.completion_update = 1;
500 	hw_desc->size = 8;
501 	hw_desc->src_addr = 0;
502 	hw_desc->dest_addr = 0;
503 	hw_desc->u.control.null = 1;
504 
505 	ioat_submit_single(ioat);
506 	ioat_release(&ioat->dmaengine);
507 
508 	for (i = 0; i < 100; i++) {
509 		DELAY(1);
510 		status = ioat_get_chansts(ioat);
511 		if (is_ioat_idle(status))
512 			return (0);
513 	}
514 
515 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
516 	ioat_log_message(0, "could not start channel: "
517 	    "status = %#jx error = %b\n", (uintmax_t)status, (int)chanerr,
518 	    IOAT_CHANERR_STR);
519 	return (ENXIO);
520 }
521 
522 /*
523  * Initialize Hardware
524  */
525 static int
526 ioat3_attach(device_t device)
527 {
528 	struct ioat_softc *ioat;
529 	struct ioat_descriptor *ring;
530 	struct ioat_dma_hw_descriptor *dma_hw_desc;
531 	void *hw_desc;
532 	bus_addr_t lowaddr;
533 	size_t ringsz;
534 	int i, num_descriptors;
535 	int error;
536 	uint8_t xfercap;
537 
538 	error = 0;
539 	ioat = DEVICE2SOFTC(device);
540 	ioat->capabilities = ioat_read_dmacapability(ioat);
541 
542 	ioat_log_message(0, "Capabilities: %b\n", (int)ioat->capabilities,
543 	    IOAT_DMACAP_STR);
544 
545 	xfercap = ioat_read_xfercap(ioat);
546 	ioat->max_xfer_size = 1 << xfercap;
547 
548 	ioat->intrdelay_supported = (ioat_read_2(ioat, IOAT_INTRDELAY_OFFSET) &
549 	    IOAT_INTRDELAY_SUPPORTED) != 0;
550 	if (ioat->intrdelay_supported)
551 		ioat->intrdelay_max = IOAT_INTRDELAY_US_MASK;
552 
553 	/* TODO: need to check DCA here if we ever do XOR/PQ */
554 
555 	mtx_init(&ioat->submit_lock, "ioat_submit", NULL, MTX_DEF);
556 	mtx_init(&ioat->cleanup_lock, "ioat_cleanup", NULL, MTX_DEF);
557 	callout_init(&ioat->poll_timer, 1);
558 	TASK_INIT(&ioat->reset_task, 0, ioat_reset_hw_task, ioat);
559 
560 	/* Establish lock order for Witness */
561 	mtx_lock(&ioat->cleanup_lock);
562 	mtx_lock(&ioat->submit_lock);
563 	mtx_unlock(&ioat->submit_lock);
564 	mtx_unlock(&ioat->cleanup_lock);
565 
566 	ioat->is_submitter_processing = FALSE;
567 
568 	if (ioat->version >= IOAT_VER_3_3)
569 		lowaddr = BUS_SPACE_MAXADDR_48BIT;
570 	else if (ioat->version >= IOAT_VER_3_2)
571 		lowaddr = BUS_SPACE_MAXADDR_46BIT;
572 	else
573 		lowaddr = BUS_SPACE_MAXADDR_40BIT;
574 
575 	error = bus_dma_tag_create(bus_get_dma_tag(ioat->device),
576 	    sizeof(uint64_t), 0x0, lowaddr, BUS_SPACE_MAXADDR, NULL, NULL,
577 	    sizeof(uint64_t), 1, sizeof(uint64_t), 0, NULL, NULL,
578 	    &ioat->comp_update_tag);
579 	if (error != 0)
580 		return (error);
581 
582 	error = bus_dmamem_alloc(ioat->comp_update_tag,
583 	    (void **)&ioat->comp_update, BUS_DMA_ZERO | BUS_DMA_WAITOK,
584 	    &ioat->comp_update_map);
585 	if (error != 0)
586 		return (error);
587 
588 	error = bus_dmamap_load(ioat->comp_update_tag, ioat->comp_update_map,
589 	    ioat->comp_update, sizeof(uint64_t), ioat_comp_update_map, ioat,
590 	    BUS_DMA_NOWAIT);
591 	if (error != 0)
592 		return (error);
593 
594 	ioat->ring_size_order = g_ioat_ring_order;
595 	num_descriptors = 1 << ioat->ring_size_order;
596 	ringsz = sizeof(struct ioat_dma_hw_descriptor) * num_descriptors;
597 
598 	error = bus_dma_tag_create(bus_get_dma_tag(ioat->device),
599 	    2 * 1024 * 1024, 0x0, lowaddr, BUS_SPACE_MAXADDR, NULL, NULL,
600 	    ringsz, 1, ringsz, 0, NULL, NULL, &ioat->hw_desc_tag);
601 	if (error != 0)
602 		return (error);
603 
604 	error = bus_dmamem_alloc(ioat->hw_desc_tag, &hw_desc,
605 	    BUS_DMA_ZERO | BUS_DMA_WAITOK, &ioat->hw_desc_map);
606 	if (error != 0)
607 		return (error);
608 
609 	error = bus_dmamap_load(ioat->hw_desc_tag, ioat->hw_desc_map, hw_desc,
610 	    ringsz, ioat_dmamap_cb, &ioat->hw_desc_bus_addr, BUS_DMA_NOWAIT);
611 	if (error)
612 		return (error);
613 
614 	ioat->hw_desc_ring = hw_desc;
615 
616 	error = bus_dma_tag_create(bus_get_dma_tag(ioat->device),
617 	    1, 0, lowaddr, BUS_SPACE_MAXADDR, NULL, NULL,
618 	    ioat->max_xfer_size, 1, ioat->max_xfer_size, 0, NULL, NULL,
619 	    &ioat->data_tag);
620 	if (error != 0)
621 		return (error);
622 	ioat->ring = malloc_domainset(num_descriptors * sizeof(*ring), M_IOAT,
623 	    DOMAINSET_PREF(ioat->domain), M_ZERO | M_WAITOK);
624 
625 	ring = ioat->ring;
626 	for (i = 0; i < num_descriptors; i++) {
627 		memset(&ring[i].bus_dmadesc, 0, sizeof(ring[i].bus_dmadesc));
628 		ring[i].id = i;
629 		error = bus_dmamap_create(ioat->data_tag, 0,
630                     &ring[i].src_dmamap);
631 		if (error != 0) {
632 			ioat_log_message(0,
633 			    "%s: bus_dmamap_create failed %d\n", __func__,
634 			    error);
635 			return (error);
636 		}
637 		error = bus_dmamap_create(ioat->data_tag, 0,
638                     &ring[i].dst_dmamap);
639 		if (error != 0) {
640 			ioat_log_message(0,
641 			    "%s: bus_dmamap_create failed %d\n", __func__,
642 			    error);
643 			return (error);
644 		}
645 		error = bus_dmamap_create(ioat->data_tag, 0,
646                     &ring[i].src2_dmamap);
647 		if (error != 0) {
648 			ioat_log_message(0,
649 			    "%s: bus_dmamap_create failed %d\n", __func__,
650 			    error);
651 			return (error);
652 		}
653 		error = bus_dmamap_create(ioat->data_tag, 0,
654                     &ring[i].dst2_dmamap);
655 		if (error != 0) {
656 			ioat_log_message(0,
657 			    "%s: bus_dmamap_create failed %d\n", __func__,
658 			    error);
659 			return (error);
660 		}
661 	}
662 
663 	for (i = 0; i < num_descriptors; i++) {
664 		dma_hw_desc = &ioat->hw_desc_ring[i].dma;
665 		dma_hw_desc->next = RING_PHYS_ADDR(ioat, i + 1);
666 	}
667 
668 	ioat->tail = ioat->head = 0;
669 	*ioat->comp_update = ioat->last_seen =
670 	    RING_PHYS_ADDR(ioat, ioat->tail - 1);
671 	return (0);
672 }
673 
674 static int
675 ioat_map_pci_bar(struct ioat_softc *ioat)
676 {
677 
678 	ioat->pci_resource_id = PCIR_BAR(0);
679 	ioat->pci_resource = bus_alloc_resource_any(ioat->device,
680 	    SYS_RES_MEMORY, &ioat->pci_resource_id, RF_ACTIVE);
681 
682 	if (ioat->pci_resource == NULL) {
683 		ioat_log_message(0, "unable to allocate pci resource\n");
684 		return (ENODEV);
685 	}
686 
687 	ioat->pci_bus_tag = rman_get_bustag(ioat->pci_resource);
688 	ioat->pci_bus_handle = rman_get_bushandle(ioat->pci_resource);
689 	return (0);
690 }
691 
692 static void
693 ioat_comp_update_map(void *arg, bus_dma_segment_t *seg, int nseg, int error)
694 {
695 	struct ioat_softc *ioat = arg;
696 
697 	KASSERT(error == 0, ("%s: error:%d", __func__, error));
698 	ioat->comp_update_bus_addr = seg[0].ds_addr;
699 }
700 
701 static void
702 ioat_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nseg, int error)
703 {
704 	bus_addr_t *baddr;
705 
706 	KASSERT(error == 0, ("%s: error:%d", __func__, error));
707 	baddr = arg;
708 	*baddr = segs->ds_addr;
709 }
710 
711 /*
712  * Interrupt setup and handlers
713  */
714 static int
715 ioat_setup_intr(struct ioat_softc *ioat)
716 {
717 	uint32_t num_vectors;
718 	int error;
719 	boolean_t use_msix;
720 
721 	use_msix = FALSE;
722 
723 	if (!g_force_legacy_interrupts && pci_msix_count(ioat->device) >= 1) {
724 		num_vectors = 1;
725 		pci_alloc_msix(ioat->device, &num_vectors);
726 		if (num_vectors == 1)
727 			use_msix = TRUE;
728 	}
729 
730 	if (use_msix) {
731 		ioat->rid = 1;
732 		ioat->res = bus_alloc_resource_any(ioat->device, SYS_RES_IRQ,
733 		    &ioat->rid, RF_ACTIVE);
734 	} else {
735 		ioat->rid = 0;
736 		ioat->res = bus_alloc_resource_any(ioat->device, SYS_RES_IRQ,
737 		    &ioat->rid, RF_SHAREABLE | RF_ACTIVE);
738 	}
739 	if (ioat->res == NULL) {
740 		ioat_log_message(0, "bus_alloc_resource failed\n");
741 		return (ENOMEM);
742 	}
743 
744 	ioat->tag = NULL;
745 	error = bus_setup_intr(ioat->device, ioat->res, INTR_MPSAFE |
746 	    INTR_TYPE_MISC, NULL, ioat_interrupt_handler, ioat, &ioat->tag);
747 	if (error != 0) {
748 		ioat_log_message(0, "bus_setup_intr failed\n");
749 		return (error);
750 	}
751 
752 	ioat_write_intrctrl(ioat, IOAT_INTRCTRL_MASTER_INT_EN);
753 	return (0);
754 }
755 
756 static boolean_t
757 ioat_model_resets_msix(struct ioat_softc *ioat)
758 {
759 	u_int32_t pciid;
760 
761 	pciid = pci_get_devid(ioat->device);
762 	switch (pciid) {
763 		/* BWD: */
764 	case 0x0c508086:
765 	case 0x0c518086:
766 	case 0x0c528086:
767 	case 0x0c538086:
768 		/* BDXDE: */
769 	case 0x6f508086:
770 	case 0x6f518086:
771 	case 0x6f528086:
772 	case 0x6f538086:
773 		return (TRUE);
774 	}
775 
776 	return (FALSE);
777 }
778 
779 static void
780 ioat_interrupt_handler(void *arg)
781 {
782 	struct ioat_softc *ioat = arg;
783 
784 	ioat->stats.interrupts++;
785 	ioat_process_events(ioat, TRUE);
786 }
787 
788 static int
789 chanerr_to_errno(uint32_t chanerr)
790 {
791 
792 	if (chanerr == 0)
793 		return (0);
794 	if ((chanerr & (IOAT_CHANERR_XSADDERR | IOAT_CHANERR_XDADDERR)) != 0)
795 		return (EFAULT);
796 	if ((chanerr & (IOAT_CHANERR_RDERR | IOAT_CHANERR_WDERR)) != 0)
797 		return (EIO);
798 	/* This one is probably our fault: */
799 	if ((chanerr & IOAT_CHANERR_NDADDERR) != 0)
800 		return (EIO);
801 	return (EIO);
802 }
803 
804 static void
805 ioat_process_events(struct ioat_softc *ioat, boolean_t intr)
806 {
807 	struct ioat_descriptor *desc;
808 	struct bus_dmadesc *dmadesc;
809 	uint64_t comp_update, status;
810 	uint32_t completed, chanerr;
811 	int error __diagused;
812 
813 	if (intr) {
814 		mtx_lock(&ioat->cleanup_lock);
815 	} else {
816 		if (!mtx_trylock(&ioat->cleanup_lock))
817 			return;
818 	}
819 
820 	/*
821 	 * Don't run while the hardware is being reset.  Reset is responsible
822 	 * for blocking new work and draining & completing existing work, so
823 	 * there is nothing to do until new work is queued after reset anyway.
824 	 */
825 	if (ioat->resetting_cleanup) {
826 		mtx_unlock(&ioat->cleanup_lock);
827 		return;
828 	}
829 
830 	completed = 0;
831 	comp_update = *ioat->comp_update;
832 	status = comp_update & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_MASK;
833 
834 	if (status < ioat->hw_desc_bus_addr ||
835 	    status >= ioat->hw_desc_bus_addr + (1 << ioat->ring_size_order) *
836 	    sizeof(struct ioat_generic_hw_descriptor))
837 		panic("Bogus completion address %jx (channel %u)",
838 		    (uintmax_t)status, ioat->chan_idx);
839 
840 	if (status == ioat->last_seen) {
841 		/*
842 		 * If we landed in process_events and nothing has been
843 		 * completed, check for a timeout due to channel halt.
844 		 */
845 		goto out;
846 	}
847 	CTR4(KTR_IOAT, "%s channel=%u hw_status=0x%lx last_seen=0x%lx",
848 	    __func__, ioat->chan_idx, comp_update, ioat->last_seen);
849 
850 	while (RING_PHYS_ADDR(ioat, ioat->tail - 1) != status) {
851 		desc = ioat_get_ring_entry(ioat, ioat->tail);
852 		dmadesc = &desc->bus_dmadesc;
853 		CTR5(KTR_IOAT, "channel=%u completing desc idx %u (%p) ok  cb %p(%p)",
854 		    ioat->chan_idx, ioat->tail, dmadesc, dmadesc->callback_fn,
855 		    dmadesc->callback_arg);
856 
857 		bus_dmamap_unload(ioat->data_tag, desc->src_dmamap);
858 		bus_dmamap_unload(ioat->data_tag, desc->dst_dmamap);
859 		bus_dmamap_unload(ioat->data_tag, desc->src2_dmamap);
860 		bus_dmamap_unload(ioat->data_tag, desc->dst2_dmamap);
861 
862 		if (dmadesc->callback_fn != NULL)
863 			dmadesc->callback_fn(dmadesc->callback_arg, 0);
864 
865 		completed++;
866 		ioat->tail++;
867 	}
868 	CTR5(KTR_IOAT, "%s channel=%u head=%u tail=%u active=%u", __func__,
869 	    ioat->chan_idx, ioat->head, ioat->tail, ioat_get_active(ioat));
870 
871 	if (completed != 0) {
872 		ioat->last_seen = RING_PHYS_ADDR(ioat, ioat->tail - 1);
873 		ioat->stats.descriptors_processed += completed;
874 		wakeup(&ioat->tail);
875 	}
876 
877 out:
878 	ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
879 	mtx_unlock(&ioat->cleanup_lock);
880 
881 	/*
882 	 * The device doesn't seem to reliably push suspend/halt statuses to
883 	 * the channel completion memory address, so poll the device register
884 	 * here.  For performance reasons skip it on interrupts, do it only
885 	 * on much more rare polling events.
886 	 */
887 	if (!intr)
888 		comp_update = ioat_get_chansts(ioat) & IOAT_CHANSTS_STATUS;
889 	if (!is_ioat_halted(comp_update) && !is_ioat_suspended(comp_update))
890 		return;
891 
892 	ioat->stats.channel_halts++;
893 
894 	/*
895 	 * Fatal programming error on this DMA channel.  Flush any outstanding
896 	 * work with error status and restart the engine.
897 	 */
898 	mtx_lock(&ioat->submit_lock);
899 	ioat->quiescing = TRUE;
900 	mtx_unlock(&ioat->submit_lock);
901 
902 	/*
903 	 * This is safe to do here because the submit queue is quiesced.  We
904 	 * know that we will drain all outstanding events, so ioat_reset_hw
905 	 * can't deadlock. It is necessary to protect other ioat_process_event
906 	 * threads from racing ioat_reset_hw, reading an indeterminate hw
907 	 * state, and attempting to continue issuing completions.
908 	 */
909 	mtx_lock(&ioat->cleanup_lock);
910 	ioat->resetting_cleanup = TRUE;
911 
912 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
913 	if (1 <= g_ioat_debug_level)
914 		ioat_halted_debug(ioat, chanerr);
915 	ioat->stats.last_halt_chanerr = chanerr;
916 
917 	while (ioat_get_active(ioat) > 0) {
918 		desc = ioat_get_ring_entry(ioat, ioat->tail);
919 		dmadesc = &desc->bus_dmadesc;
920 		CTR5(KTR_IOAT, "channel=%u completing desc idx %u (%p) err cb %p(%p)",
921 		    ioat->chan_idx, ioat->tail, dmadesc, dmadesc->callback_fn,
922 		    dmadesc->callback_arg);
923 
924 		if (dmadesc->callback_fn != NULL)
925 			dmadesc->callback_fn(dmadesc->callback_arg,
926 			    chanerr_to_errno(chanerr));
927 
928 		ioat->tail++;
929 		ioat->stats.descriptors_processed++;
930 		ioat->stats.descriptors_error++;
931 	}
932 	CTR5(KTR_IOAT, "%s channel=%u head=%u tail=%u active=%u", __func__,
933 	    ioat->chan_idx, ioat->head, ioat->tail, ioat_get_active(ioat));
934 
935 	/* Clear error status */
936 	ioat_write_4(ioat, IOAT_CHANERR_OFFSET, chanerr);
937 
938 	mtx_unlock(&ioat->cleanup_lock);
939 
940 	ioat_log_message(0, "Resetting channel to recover from error\n");
941 	error = taskqueue_enqueue(taskqueue_thread, &ioat->reset_task);
942 	KASSERT(error == 0,
943 	    ("%s: taskqueue_enqueue failed: %d", __func__, error));
944 }
945 
946 static void
947 ioat_reset_hw_task(void *ctx, int pending __unused)
948 {
949 	struct ioat_softc *ioat;
950 	int error __diagused;
951 
952 	ioat = ctx;
953 	ioat_log_message(1, "%s: Resetting channel\n", __func__);
954 
955 	error = ioat_reset_hw(ioat);
956 	KASSERT(error == 0, ("%s: reset failed: %d", __func__, error));
957 }
958 
959 /*
960  * User API functions
961  */
962 unsigned
963 ioat_get_nchannels(void)
964 {
965 
966 	return (ioat_channel_index);
967 }
968 
969 bus_dmaengine_t
970 ioat_get_dmaengine(uint32_t index, int flags)
971 {
972 	struct ioat_softc *ioat;
973 
974 	KASSERT((flags & ~(M_NOWAIT | M_WAITOK)) == 0,
975 	    ("invalid flags: 0x%08x", flags));
976 	KASSERT((flags & (M_NOWAIT | M_WAITOK)) != (M_NOWAIT | M_WAITOK),
977 	    ("invalid wait | nowait"));
978 
979 	mtx_lock(&ioat_list_mtx);
980 	if (index >= ioat_channel_index ||
981 	    (ioat = ioat_channel[index]) == NULL) {
982 		mtx_unlock(&ioat_list_mtx);
983 		return (NULL);
984 	}
985 	mtx_lock(&ioat->submit_lock);
986 	mtx_unlock(&ioat_list_mtx);
987 
988 	if (ioat->destroying) {
989 		mtx_unlock(&ioat->submit_lock);
990 		return (NULL);
991 	}
992 
993 	ioat_get(ioat);
994 	if (ioat->quiescing) {
995 		if ((flags & M_NOWAIT) != 0) {
996 			ioat_put(ioat);
997 			mtx_unlock(&ioat->submit_lock);
998 			return (NULL);
999 		}
1000 
1001 		while (ioat->quiescing && !ioat->destroying)
1002 			msleep(&ioat->quiescing, &ioat->submit_lock, 0, "getdma", 0);
1003 
1004 		if (ioat->destroying) {
1005 			ioat_put(ioat);
1006 			mtx_unlock(&ioat->submit_lock);
1007 			return (NULL);
1008 		}
1009 	}
1010 	mtx_unlock(&ioat->submit_lock);
1011 	return (&ioat->dmaengine);
1012 }
1013 
1014 void
1015 ioat_put_dmaengine(bus_dmaengine_t dmaengine)
1016 {
1017 	struct ioat_softc *ioat;
1018 
1019 	ioat = to_ioat_softc(dmaengine);
1020 	mtx_lock(&ioat->submit_lock);
1021 	ioat_put(ioat);
1022 	mtx_unlock(&ioat->submit_lock);
1023 }
1024 
1025 int
1026 ioat_get_hwversion(bus_dmaengine_t dmaengine)
1027 {
1028 	struct ioat_softc *ioat;
1029 
1030 	ioat = to_ioat_softc(dmaengine);
1031 	return (ioat->version);
1032 }
1033 
1034 size_t
1035 ioat_get_max_io_size(bus_dmaengine_t dmaengine)
1036 {
1037 	struct ioat_softc *ioat;
1038 
1039 	ioat = to_ioat_softc(dmaengine);
1040 	return (ioat->max_xfer_size);
1041 }
1042 
1043 uint32_t
1044 ioat_get_capabilities(bus_dmaengine_t dmaengine)
1045 {
1046 	struct ioat_softc *ioat;
1047 
1048 	ioat = to_ioat_softc(dmaengine);
1049 	return (ioat->capabilities);
1050 }
1051 
1052 int
1053 ioat_get_domain(bus_dmaengine_t dmaengine, int *domain)
1054 {
1055 	struct ioat_softc *ioat;
1056 
1057 	ioat = to_ioat_softc(dmaengine);
1058 	return (bus_get_domain(ioat->device, domain));
1059 }
1060 
1061 int
1062 ioat_set_interrupt_coalesce(bus_dmaengine_t dmaengine, uint16_t delay)
1063 {
1064 	struct ioat_softc *ioat;
1065 
1066 	ioat = to_ioat_softc(dmaengine);
1067 	if (!ioat->intrdelay_supported)
1068 		return (ENODEV);
1069 	if (delay > ioat->intrdelay_max)
1070 		return (ERANGE);
1071 
1072 	ioat_write_2(ioat, IOAT_INTRDELAY_OFFSET, delay);
1073 	ioat->cached_intrdelay =
1074 	    ioat_read_2(ioat, IOAT_INTRDELAY_OFFSET) & IOAT_INTRDELAY_US_MASK;
1075 	return (0);
1076 }
1077 
1078 uint16_t
1079 ioat_get_max_coalesce_period(bus_dmaengine_t dmaengine)
1080 {
1081 	struct ioat_softc *ioat;
1082 
1083 	ioat = to_ioat_softc(dmaengine);
1084 	return (ioat->intrdelay_max);
1085 }
1086 
1087 void
1088 ioat_acquire(bus_dmaengine_t dmaengine)
1089 {
1090 	struct ioat_softc *ioat;
1091 
1092 	ioat = to_ioat_softc(dmaengine);
1093 	mtx_lock(&ioat->submit_lock);
1094 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1095 	ioat->acq_head = ioat->head;
1096 }
1097 
1098 int
1099 ioat_acquire_reserve(bus_dmaengine_t dmaengine, unsigned n, int mflags)
1100 {
1101 	struct ioat_softc *ioat;
1102 	int error;
1103 
1104 	ioat = to_ioat_softc(dmaengine);
1105 	ioat_acquire(dmaengine);
1106 
1107 	error = ioat_reserve_space(ioat, n, mflags);
1108 	if (error != 0)
1109 		ioat_release(dmaengine);
1110 	return (error);
1111 }
1112 
1113 void
1114 ioat_release(bus_dmaengine_t dmaengine)
1115 {
1116 	struct ioat_softc *ioat;
1117 
1118 	ioat = to_ioat_softc(dmaengine);
1119 	CTR3(KTR_IOAT, "%s channel=%u dispatch1 head=%u", __func__,
1120 	    ioat->chan_idx, ioat->head);
1121 	KFAIL_POINT_CODE(DEBUG_FP, ioat_release, /* do nothing */);
1122 	CTR3(KTR_IOAT, "%s channel=%u dispatch2 head=%u", __func__,
1123 	    ioat->chan_idx, ioat->head);
1124 
1125 	if (ioat->acq_head != ioat->head) {
1126 		ioat_write_2(ioat, IOAT_DMACOUNT_OFFSET,
1127 		    (uint16_t)ioat->head);
1128 
1129 		if (!callout_pending(&ioat->poll_timer)) {
1130 			callout_reset_on(&ioat->poll_timer, 1,
1131 			    ioat_poll_timer_callback, ioat, ioat->cpu);
1132 		}
1133 	}
1134 	mtx_unlock(&ioat->submit_lock);
1135 }
1136 
1137 static struct ioat_descriptor *
1138 ioat_op_generic(struct ioat_softc *ioat, uint8_t op,
1139     uint32_t size, uint64_t src, uint64_t dst,
1140     bus_dmaengine_callback_t callback_fn, void *callback_arg,
1141     uint32_t flags)
1142 {
1143 	struct ioat_generic_hw_descriptor *hw_desc;
1144 	struct ioat_descriptor *desc;
1145 	bus_dma_segment_t seg;
1146 	int mflags, nseg, error;
1147 
1148 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1149 
1150 	KASSERT((flags & ~_DMA_GENERIC_FLAGS) == 0,
1151 	    ("Unrecognized flag(s): %#x", flags & ~_DMA_GENERIC_FLAGS));
1152 	KASSERT(size <= ioat->max_xfer_size, ("%s: size too big (%u > %u)",
1153 	    __func__, (unsigned)size, ioat->max_xfer_size));
1154 
1155 	if ((flags & DMA_NO_WAIT) != 0)
1156 		mflags = M_NOWAIT;
1157 	else
1158 		mflags = M_WAITOK;
1159 
1160 	if (ioat_reserve_space(ioat, 1, mflags) != 0)
1161 		return (NULL);
1162 
1163 	desc = ioat_get_ring_entry(ioat, ioat->head);
1164 	hw_desc = &ioat_get_descriptor(ioat, ioat->head)->generic;
1165 
1166 	hw_desc->u.control_raw = 0;
1167 	hw_desc->u.control_generic.op = op;
1168 	hw_desc->u.control_generic.completion_update = 1;
1169 
1170 	if ((flags & DMA_INT_EN) != 0)
1171 		hw_desc->u.control_generic.int_enable = 1;
1172 	if ((flags & DMA_FENCE) != 0)
1173 		hw_desc->u.control_generic.fence = 1;
1174 
1175 	hw_desc->size = size;
1176 
1177 	if (src != 0) {
1178 		nseg = -1;
1179 		error = _bus_dmamap_load_phys(ioat->data_tag, desc->src_dmamap,
1180 		    src, size, 0, &seg, &nseg);
1181 		if (error != 0) {
1182 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1183 			    " failed %d\n", __func__, error);
1184 			return (NULL);
1185 		}
1186 		hw_desc->src_addr = seg.ds_addr;
1187 	}
1188 
1189 	if (dst != 0) {
1190 		nseg = -1;
1191 		error = _bus_dmamap_load_phys(ioat->data_tag, desc->dst_dmamap,
1192 		    dst, size, 0, &seg, &nseg);
1193 		if (error != 0) {
1194 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1195 			    " failed %d\n", __func__, error);
1196 			return (NULL);
1197 		}
1198 		hw_desc->dest_addr = seg.ds_addr;
1199 	}
1200 
1201 	desc->bus_dmadesc.callback_fn = callback_fn;
1202 	desc->bus_dmadesc.callback_arg = callback_arg;
1203 	return (desc);
1204 }
1205 
1206 struct bus_dmadesc *
1207 ioat_null(bus_dmaengine_t dmaengine, bus_dmaengine_callback_t callback_fn,
1208     void *callback_arg, uint32_t flags)
1209 {
1210 	struct ioat_dma_hw_descriptor *hw_desc;
1211 	struct ioat_descriptor *desc;
1212 	struct ioat_softc *ioat;
1213 
1214 	ioat = to_ioat_softc(dmaengine);
1215 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1216 
1217 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, 8, 0, 0, callback_fn,
1218 	    callback_arg, flags);
1219 	if (desc == NULL)
1220 		return (NULL);
1221 
1222 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->dma;
1223 	hw_desc->u.control.null = 1;
1224 	ioat_submit_single(ioat);
1225 	return (&desc->bus_dmadesc);
1226 }
1227 
1228 struct bus_dmadesc *
1229 ioat_copy(bus_dmaengine_t dmaengine, bus_addr_t dst,
1230     bus_addr_t src, bus_size_t len, bus_dmaengine_callback_t callback_fn,
1231     void *callback_arg, uint32_t flags)
1232 {
1233 	struct ioat_dma_hw_descriptor *hw_desc;
1234 	struct ioat_descriptor *desc;
1235 	struct ioat_softc *ioat;
1236 
1237 	ioat = to_ioat_softc(dmaengine);
1238 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, len, src, dst, callback_fn,
1239 	    callback_arg, flags);
1240 	if (desc == NULL)
1241 		return (NULL);
1242 
1243 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->dma;
1244 	if (g_ioat_debug_level >= 3)
1245 		dump_descriptor(hw_desc);
1246 
1247 	ioat_submit_single(ioat);
1248 	CTR6(KTR_IOAT, "%s channel=%u desc=%p dest=%lx src=%lx len=%lx",
1249 	    __func__, ioat->chan_idx, &desc->bus_dmadesc, dst, src, len);
1250 	return (&desc->bus_dmadesc);
1251 }
1252 
1253 struct bus_dmadesc *
1254 ioat_copy_8k_aligned(bus_dmaengine_t dmaengine, bus_addr_t dst1,
1255     bus_addr_t dst2, bus_addr_t src1, bus_addr_t src2,
1256     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags)
1257 {
1258 	struct ioat_dma_hw_descriptor *hw_desc;
1259 	struct ioat_descriptor *desc;
1260 	struct ioat_softc *ioat;
1261 	bus_size_t src1_len, dst1_len;
1262 	bus_dma_segment_t seg;
1263 	int nseg, error;
1264 
1265 	ioat = to_ioat_softc(dmaengine);
1266 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1267 
1268 	KASSERT(((src1 | src2 | dst1 | dst2) & PAGE_MASK) == 0,
1269 	    ("%s: addresses are not page-aligned", __func__));
1270 
1271 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, 2 * PAGE_SIZE, 0, 0,
1272 	    callback_fn, callback_arg, flags);
1273 	if (desc == NULL)
1274 		return (NULL);
1275 
1276 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->dma;
1277 
1278 	src1_len = (src2 != src1 + PAGE_SIZE) ? PAGE_SIZE : 2 * PAGE_SIZE;
1279 	nseg = -1;
1280 	error = _bus_dmamap_load_phys(ioat->data_tag,
1281 	    desc->src_dmamap, src1, src1_len, 0, &seg, &nseg);
1282 	if (error != 0) {
1283 		ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1284 		    " failed %d\n", __func__, error);
1285 		return (NULL);
1286 	}
1287 	hw_desc->src_addr = seg.ds_addr;
1288 	if (src1_len != 2 * PAGE_SIZE) {
1289 		hw_desc->u.control.src_page_break = 1;
1290 		nseg = -1;
1291 		error = _bus_dmamap_load_phys(ioat->data_tag,
1292 		    desc->src2_dmamap, src2, PAGE_SIZE, 0, &seg, &nseg);
1293 		if (error != 0) {
1294 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1295 			    " failed %d\n", __func__, error);
1296 			return (NULL);
1297 		}
1298 		hw_desc->next_src_addr = seg.ds_addr;
1299 	}
1300 
1301 	dst1_len = (dst2 != dst1 + PAGE_SIZE) ? PAGE_SIZE : 2 * PAGE_SIZE;
1302 	nseg = -1;
1303 	error = _bus_dmamap_load_phys(ioat->data_tag,
1304 	    desc->dst_dmamap, dst1, dst1_len, 0, &seg, &nseg);
1305 	if (error != 0) {
1306 		ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1307 		    " failed %d\n", __func__, error);
1308 		return (NULL);
1309 	}
1310 	hw_desc->dest_addr = seg.ds_addr;
1311 	if (dst1_len != 2 * PAGE_SIZE) {
1312 		hw_desc->u.control.dest_page_break = 1;
1313 		nseg = -1;
1314 		error = _bus_dmamap_load_phys(ioat->data_tag,
1315 		    desc->dst2_dmamap, dst2, PAGE_SIZE, 0, &seg, &nseg);
1316 		if (error != 0) {
1317 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1318 			    " failed %d\n", __func__, error);
1319 			return (NULL);
1320 		}
1321 		hw_desc->next_dest_addr = seg.ds_addr;
1322 	}
1323 
1324 	if (g_ioat_debug_level >= 3)
1325 		dump_descriptor(hw_desc);
1326 
1327 	ioat_submit_single(ioat);
1328 	return (&desc->bus_dmadesc);
1329 }
1330 
1331 struct bus_dmadesc *
1332 ioat_copy_crc(bus_dmaengine_t dmaengine, bus_addr_t dst, bus_addr_t src,
1333     bus_size_t len, uint32_t *initialseed, bus_addr_t crcptr,
1334     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags)
1335 {
1336 	struct ioat_crc32_hw_descriptor *hw_desc;
1337 	struct ioat_descriptor *desc;
1338 	struct ioat_softc *ioat;
1339 	uint32_t teststore;
1340 	uint8_t op;
1341 	bus_dma_segment_t seg;
1342 	int nseg, error;
1343 
1344 	ioat = to_ioat_softc(dmaengine);
1345 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1346 
1347 	KASSERT((ioat->capabilities & IOAT_DMACAP_MOVECRC) != 0,
1348 	    ("%s: device lacks MOVECRC capability", __func__));
1349 	teststore = (flags & _DMA_CRC_TESTSTORE);
1350 	KASSERT(teststore != _DMA_CRC_TESTSTORE,
1351 	    ("%s: TEST and STORE invalid", __func__));
1352 	KASSERT(teststore != 0 || (flags & DMA_CRC_INLINE) == 0,
1353 	    ("%s: INLINE invalid without TEST or STORE", __func__));
1354 
1355 	switch (teststore) {
1356 	case DMA_CRC_STORE:
1357 		op = IOAT_OP_MOVECRC_STORE;
1358 		break;
1359 	case DMA_CRC_TEST:
1360 		op = IOAT_OP_MOVECRC_TEST;
1361 		break;
1362 	default:
1363 		KASSERT(teststore == 0, ("bogus"));
1364 		op = IOAT_OP_MOVECRC;
1365 		break;
1366 	}
1367 
1368 	desc = ioat_op_generic(ioat, op, len, src, dst, callback_fn,
1369 	    callback_arg, flags & ~_DMA_CRC_FLAGS);
1370 	if (desc == NULL)
1371 		return (NULL);
1372 
1373 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->crc32;
1374 
1375 	if ((flags & DMA_CRC_INLINE) == 0) {
1376 		nseg = -1;
1377 		error = _bus_dmamap_load_phys(ioat->data_tag,
1378 		    desc->dst2_dmamap, crcptr, sizeof(uint32_t), 0,
1379 		    &seg, &nseg);
1380 		if (error != 0) {
1381 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1382 			    " failed %d\n", __func__, error);
1383 			return (NULL);
1384 		}
1385 		hw_desc->crc_address = seg.ds_addr;
1386 	} else
1387 		hw_desc->u.control.crc_location = 1;
1388 
1389 	if (initialseed != NULL) {
1390 		hw_desc->u.control.use_seed = 1;
1391 		hw_desc->seed = *initialseed;
1392 	}
1393 
1394 	if (g_ioat_debug_level >= 3)
1395 		dump_descriptor(hw_desc);
1396 
1397 	ioat_submit_single(ioat);
1398 	return (&desc->bus_dmadesc);
1399 }
1400 
1401 struct bus_dmadesc *
1402 ioat_crc(bus_dmaengine_t dmaengine, bus_addr_t src, bus_size_t len,
1403     uint32_t *initialseed, bus_addr_t crcptr,
1404     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags)
1405 {
1406 	struct ioat_crc32_hw_descriptor *hw_desc;
1407 	struct ioat_descriptor *desc;
1408 	struct ioat_softc *ioat;
1409 	uint32_t teststore;
1410 	uint8_t op;
1411 	bus_dma_segment_t seg;
1412 	int nseg, error;
1413 
1414 	ioat = to_ioat_softc(dmaengine);
1415 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1416 
1417 	KASSERT((ioat->capabilities & IOAT_DMACAP_CRC) != 0,
1418 	    ("%s: device lacks CRC capability", __func__));
1419 	teststore = (flags & _DMA_CRC_TESTSTORE);
1420 	KASSERT(teststore != _DMA_CRC_TESTSTORE,
1421 	    ("%s: TEST and STORE invalid", __func__));
1422 	KASSERT(teststore != 0 || (flags & DMA_CRC_INLINE) == 0,
1423 	    ("%s: INLINE invalid without TEST or STORE", __func__));
1424 
1425 	switch (teststore) {
1426 	case DMA_CRC_STORE:
1427 		op = IOAT_OP_CRC_STORE;
1428 		break;
1429 	case DMA_CRC_TEST:
1430 		op = IOAT_OP_CRC_TEST;
1431 		break;
1432 	default:
1433 		KASSERT(teststore == 0, ("bogus"));
1434 		op = IOAT_OP_CRC;
1435 		break;
1436 	}
1437 
1438 	desc = ioat_op_generic(ioat, op, len, src, 0, callback_fn,
1439 	    callback_arg, flags & ~_DMA_CRC_FLAGS);
1440 	if (desc == NULL)
1441 		return (NULL);
1442 
1443 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->crc32;
1444 
1445 	if ((flags & DMA_CRC_INLINE) == 0) {
1446 		nseg = -1;
1447 		error = _bus_dmamap_load_phys(ioat->data_tag,
1448 		    desc->dst2_dmamap, crcptr, sizeof(uint32_t), 0,
1449 		    &seg, &nseg);
1450 		if (error != 0) {
1451 			ioat_log_message(0, "%s: _bus_dmamap_load_phys"
1452 			    " failed %d\n", __func__, error);
1453 			return (NULL);
1454 		}
1455 		hw_desc->crc_address = seg.ds_addr;
1456 	} else
1457 		hw_desc->u.control.crc_location = 1;
1458 
1459 	if (initialseed != NULL) {
1460 		hw_desc->u.control.use_seed = 1;
1461 		hw_desc->seed = *initialseed;
1462 	}
1463 
1464 	if (g_ioat_debug_level >= 3)
1465 		dump_descriptor(hw_desc);
1466 
1467 	ioat_submit_single(ioat);
1468 	return (&desc->bus_dmadesc);
1469 }
1470 
1471 struct bus_dmadesc *
1472 ioat_blockfill(bus_dmaengine_t dmaengine, bus_addr_t dst, uint64_t fillpattern,
1473     bus_size_t len, bus_dmaengine_callback_t callback_fn, void *callback_arg,
1474     uint32_t flags)
1475 {
1476 	struct ioat_fill_hw_descriptor *hw_desc;
1477 	struct ioat_descriptor *desc;
1478 	struct ioat_softc *ioat;
1479 
1480 	ioat = to_ioat_softc(dmaengine);
1481 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1482 
1483 	KASSERT((ioat->capabilities & IOAT_DMACAP_BFILL) != 0,
1484 	    ("%s: device lacks BFILL capability", __func__));
1485 
1486 	desc = ioat_op_generic(ioat, IOAT_OP_FILL, len, 0, dst,
1487 	    callback_fn, callback_arg, flags);
1488 	if (desc == NULL)
1489 		return (NULL);
1490 
1491 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->fill;
1492 	hw_desc->src_data = fillpattern;
1493 	if (g_ioat_debug_level >= 3)
1494 		dump_descriptor(hw_desc);
1495 
1496 	ioat_submit_single(ioat);
1497 	return (&desc->bus_dmadesc);
1498 }
1499 
1500 /*
1501  * Ring Management
1502  */
1503 static inline uint32_t
1504 ioat_get_active(struct ioat_softc *ioat)
1505 {
1506 
1507 	return ((ioat->head - ioat->tail) & ((1 << ioat->ring_size_order) - 1));
1508 }
1509 
1510 static inline uint32_t
1511 ioat_get_ring_space(struct ioat_softc *ioat)
1512 {
1513 
1514 	return ((1 << ioat->ring_size_order) - ioat_get_active(ioat) - 1);
1515 }
1516 
1517 /*
1518  * Reserves space in this IOAT descriptor ring by ensuring enough slots remain
1519  * for 'num_descs'.
1520  *
1521  * If mflags contains M_WAITOK, blocks until enough space is available.
1522  *
1523  * Returns zero on success, or an errno on error.  If num_descs is beyond the
1524  * maximum ring size, returns EINVAl; if allocation would block and mflags
1525  * contains M_NOWAIT, returns EAGAIN.
1526  *
1527  * Must be called with the submit_lock held; returns with the lock held.  The
1528  * lock may be dropped to allocate the ring.
1529  *
1530  * (The submit_lock is needed to add any entries to the ring, so callers are
1531  * assured enough room is available.)
1532  */
1533 static int
1534 ioat_reserve_space(struct ioat_softc *ioat, uint32_t num_descs, int mflags)
1535 {
1536 	boolean_t dug;
1537 	int error;
1538 
1539 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1540 	error = 0;
1541 	dug = FALSE;
1542 
1543 	if (num_descs < 1 || num_descs >= (1 << ioat->ring_size_order)) {
1544 		error = EINVAL;
1545 		goto out;
1546 	}
1547 
1548 	for (;;) {
1549 		if (ioat->quiescing) {
1550 			error = ENXIO;
1551 			goto out;
1552 		}
1553 
1554 		if (ioat_get_ring_space(ioat) >= num_descs)
1555 			goto out;
1556 
1557 		CTR3(KTR_IOAT, "%s channel=%u starved (%u)", __func__,
1558 		    ioat->chan_idx, num_descs);
1559 
1560 		if (!dug && !ioat->is_submitter_processing) {
1561 			ioat->is_submitter_processing = TRUE;
1562 			mtx_unlock(&ioat->submit_lock);
1563 
1564 			CTR2(KTR_IOAT, "%s channel=%u attempting to process events",
1565 			    __func__, ioat->chan_idx);
1566 			ioat_process_events(ioat, FALSE);
1567 
1568 			mtx_lock(&ioat->submit_lock);
1569 			dug = TRUE;
1570 			KASSERT(ioat->is_submitter_processing == TRUE,
1571 			    ("is_submitter_processing"));
1572 			ioat->is_submitter_processing = FALSE;
1573 			wakeup(&ioat->tail);
1574 			continue;
1575 		}
1576 
1577 		if ((mflags & M_WAITOK) == 0) {
1578 			error = EAGAIN;
1579 			break;
1580 		}
1581 		CTR2(KTR_IOAT, "%s channel=%u blocking on completions",
1582 		    __func__, ioat->chan_idx);
1583 		msleep(&ioat->tail, &ioat->submit_lock, 0,
1584 		    "ioat_full", 0);
1585 		continue;
1586 	}
1587 
1588 out:
1589 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1590 	KASSERT(!ioat->quiescing || error == ENXIO,
1591 	    ("reserved during quiesce"));
1592 	return (error);
1593 }
1594 
1595 static void
1596 ioat_free_ring(struct ioat_softc *ioat, uint32_t size,
1597     struct ioat_descriptor *ring)
1598 {
1599 
1600 	free(ring, M_IOAT);
1601 }
1602 
1603 static struct ioat_descriptor *
1604 ioat_get_ring_entry(struct ioat_softc *ioat, uint32_t index)
1605 {
1606 
1607 	return (&ioat->ring[index % (1 << ioat->ring_size_order)]);
1608 }
1609 
1610 static union ioat_hw_descriptor *
1611 ioat_get_descriptor(struct ioat_softc *ioat, uint32_t index)
1612 {
1613 
1614 	return (&ioat->hw_desc_ring[index % (1 << ioat->ring_size_order)]);
1615 }
1616 
1617 static void
1618 ioat_halted_debug(struct ioat_softc *ioat, uint32_t chanerr)
1619 {
1620 	union ioat_hw_descriptor *desc;
1621 
1622 	ioat_log_message(0, "Channel halted (%b)\n", (int)chanerr,
1623 	    IOAT_CHANERR_STR);
1624 	if (chanerr == 0)
1625 		return;
1626 
1627 	mtx_assert(&ioat->cleanup_lock, MA_OWNED);
1628 
1629 	desc = ioat_get_descriptor(ioat, ioat->tail + 0);
1630 	dump_descriptor(desc);
1631 
1632 	desc = ioat_get_descriptor(ioat, ioat->tail + 1);
1633 	dump_descriptor(desc);
1634 }
1635 
1636 static void
1637 ioat_poll_timer_callback(void *arg)
1638 {
1639 	struct ioat_softc *ioat;
1640 
1641 	ioat = arg;
1642 	CTR1(KTR_IOAT, "%s", __func__);
1643 
1644 	ioat_process_events(ioat, FALSE);
1645 
1646 	mtx_lock(&ioat->submit_lock);
1647 	if (ioat_get_active(ioat) > 0)
1648 		callout_schedule(&ioat->poll_timer, 1);
1649 	mtx_unlock(&ioat->submit_lock);
1650 }
1651 
1652 /*
1653  * Support Functions
1654  */
1655 static void
1656 ioat_submit_single(struct ioat_softc *ioat)
1657 {
1658 
1659 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1660 
1661 	ioat->head++;
1662 	CTR4(KTR_IOAT, "%s channel=%u head=%u tail=%u", __func__,
1663 	    ioat->chan_idx, ioat->head, ioat->tail);
1664 
1665 	ioat->stats.descriptors_submitted++;
1666 }
1667 
1668 static int
1669 ioat_reset_hw(struct ioat_softc *ioat)
1670 {
1671 	uint64_t status;
1672 	uint32_t chanerr;
1673 	unsigned timeout;
1674 	int error;
1675 
1676 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1677 
1678 	mtx_lock(&ioat->submit_lock);
1679 	while (ioat->resetting && !ioat->destroying)
1680 		msleep(&ioat->resetting, &ioat->submit_lock, 0, "IRH_drain", 0);
1681 	if (ioat->destroying) {
1682 		mtx_unlock(&ioat->submit_lock);
1683 		return (ENXIO);
1684 	}
1685 	ioat->resetting = TRUE;
1686 	ioat->quiescing = TRUE;
1687 	mtx_unlock(&ioat->submit_lock);
1688 	mtx_lock(&ioat->cleanup_lock);
1689 	while (ioat_get_active(ioat) > 0)
1690 		msleep(&ioat->tail, &ioat->cleanup_lock, 0, "ioat_drain", 1);
1691 
1692 	/*
1693 	 * Suspend ioat_process_events while the hardware and softc are in an
1694 	 * indeterminate state.
1695 	 */
1696 	ioat->resetting_cleanup = TRUE;
1697 	mtx_unlock(&ioat->cleanup_lock);
1698 
1699 	CTR2(KTR_IOAT, "%s channel=%u quiesced and drained", __func__,
1700 	    ioat->chan_idx);
1701 
1702 	status = ioat_get_chansts(ioat);
1703 	if (is_ioat_active(status) || is_ioat_idle(status))
1704 		ioat_suspend(ioat);
1705 
1706 	/* Wait at most 20 ms */
1707 	for (timeout = 0; (is_ioat_active(status) || is_ioat_idle(status)) &&
1708 	    timeout < 20; timeout++) {
1709 		DELAY(1000);
1710 		status = ioat_get_chansts(ioat);
1711 	}
1712 	if (timeout == 20) {
1713 		error = ETIMEDOUT;
1714 		goto out;
1715 	}
1716 
1717 	KASSERT(ioat_get_active(ioat) == 0, ("active after quiesce"));
1718 
1719 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
1720 	ioat_write_4(ioat, IOAT_CHANERR_OFFSET, chanerr);
1721 
1722 	CTR2(KTR_IOAT, "%s channel=%u hardware suspended", __func__,
1723 	    ioat->chan_idx);
1724 
1725 	/*
1726 	 * IOAT v3 workaround - CHANERRMSK_INT with 3E07h to masks out errors
1727 	 *  that can cause stability issues for IOAT v3.
1728 	 */
1729 	pci_write_config(ioat->device, IOAT_CFG_CHANERRMASK_INT_OFFSET, 0x3e07,
1730 	    4);
1731 	chanerr = pci_read_config(ioat->device, IOAT_CFG_CHANERR_INT_OFFSET, 4);
1732 	pci_write_config(ioat->device, IOAT_CFG_CHANERR_INT_OFFSET, chanerr, 4);
1733 
1734 	/*
1735 	 * BDXDE and BWD models reset MSI-X registers on device reset.
1736 	 * Save/restore their contents manually.
1737 	 */
1738 	if (ioat_model_resets_msix(ioat)) {
1739 		ioat_log_message(1, "device resets MSI-X registers; saving\n");
1740 		pci_save_state(ioat->device);
1741 	}
1742 
1743 	ioat_reset(ioat);
1744 	CTR2(KTR_IOAT, "%s channel=%u hardware reset", __func__,
1745 	    ioat->chan_idx);
1746 
1747 	/* Wait at most 20 ms */
1748 	for (timeout = 0; ioat_reset_pending(ioat) && timeout < 20; timeout++)
1749 		DELAY(1000);
1750 	if (timeout == 20) {
1751 		error = ETIMEDOUT;
1752 		goto out;
1753 	}
1754 
1755 	if (ioat_model_resets_msix(ioat)) {
1756 		ioat_log_message(1, "device resets registers; restored\n");
1757 		pci_restore_state(ioat->device);
1758 	}
1759 
1760 	/* Reset attempts to return the hardware to "halted." */
1761 	status = ioat_get_chansts(ioat);
1762 	if (is_ioat_active(status) || is_ioat_idle(status)) {
1763 		/* So this really shouldn't happen... */
1764 		ioat_log_message(0, "Device is active after a reset?\n");
1765 		ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
1766 		error = 0;
1767 		goto out;
1768 	}
1769 
1770 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
1771 	if (chanerr != 0) {
1772 		mtx_lock(&ioat->cleanup_lock);
1773 		ioat_halted_debug(ioat, chanerr);
1774 		mtx_unlock(&ioat->cleanup_lock);
1775 		error = EIO;
1776 		goto out;
1777 	}
1778 
1779 	/*
1780 	 * Bring device back online after reset.  Writing CHAINADDR brings the
1781 	 * device back to active.
1782 	 *
1783 	 * The internal ring counter resets to zero, so we have to start over
1784 	 * at zero as well.
1785 	 */
1786 	ioat->tail = ioat->head = 0;
1787 	*ioat->comp_update = ioat->last_seen =
1788 	    RING_PHYS_ADDR(ioat, ioat->tail - 1);
1789 
1790 	ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
1791 	ioat_write_chancmp(ioat, ioat->comp_update_bus_addr);
1792 	ioat_write_chainaddr(ioat, RING_PHYS_ADDR(ioat, 0));
1793 	error = 0;
1794 	CTR2(KTR_IOAT, "%s channel=%u configured channel", __func__,
1795 	    ioat->chan_idx);
1796 
1797 out:
1798 	/* Enqueues a null operation and ensures it completes. */
1799 	if (error == 0) {
1800 		error = ioat_start_channel(ioat);
1801 		CTR2(KTR_IOAT, "%s channel=%u started channel", __func__,
1802 		    ioat->chan_idx);
1803 	}
1804 
1805 	/*
1806 	 * Resume completions now that ring state is consistent.
1807 	 */
1808 	mtx_lock(&ioat->cleanup_lock);
1809 	ioat->resetting_cleanup = FALSE;
1810 	mtx_unlock(&ioat->cleanup_lock);
1811 
1812 	/* Unblock submission of new work */
1813 	mtx_lock(&ioat->submit_lock);
1814 	ioat->quiescing = FALSE;
1815 	wakeup(&ioat->quiescing);
1816 
1817 	ioat->resetting = FALSE;
1818 	wakeup(&ioat->resetting);
1819 
1820 	CTR2(KTR_IOAT, "%s channel=%u reset done", __func__, ioat->chan_idx);
1821 	mtx_unlock(&ioat->submit_lock);
1822 
1823 	return (error);
1824 }
1825 
1826 static int
1827 sysctl_handle_chansts(SYSCTL_HANDLER_ARGS)
1828 {
1829 	struct ioat_softc *ioat;
1830 	struct sbuf sb;
1831 	uint64_t status;
1832 	int error;
1833 
1834 	ioat = arg1;
1835 
1836 	status = ioat_get_chansts(ioat) & IOAT_CHANSTS_STATUS;
1837 
1838 	sbuf_new_for_sysctl(&sb, NULL, 256, req);
1839 	switch (status) {
1840 	case IOAT_CHANSTS_ACTIVE:
1841 		sbuf_printf(&sb, "ACTIVE");
1842 		break;
1843 	case IOAT_CHANSTS_IDLE:
1844 		sbuf_printf(&sb, "IDLE");
1845 		break;
1846 	case IOAT_CHANSTS_SUSPENDED:
1847 		sbuf_printf(&sb, "SUSPENDED");
1848 		break;
1849 	case IOAT_CHANSTS_HALTED:
1850 		sbuf_printf(&sb, "HALTED");
1851 		break;
1852 	case IOAT_CHANSTS_ARMED:
1853 		sbuf_printf(&sb, "ARMED");
1854 		break;
1855 	default:
1856 		sbuf_printf(&sb, "UNKNOWN");
1857 		break;
1858 	}
1859 	error = sbuf_finish(&sb);
1860 	sbuf_delete(&sb);
1861 
1862 	if (error != 0 || req->newptr == NULL)
1863 		return (error);
1864 	return (EINVAL);
1865 }
1866 
1867 static int
1868 sysctl_handle_dpi(SYSCTL_HANDLER_ARGS)
1869 {
1870 	struct ioat_softc *ioat;
1871 	struct sbuf sb;
1872 #define	PRECISION	"1"
1873 	const uintmax_t factor = 10;
1874 	uintmax_t rate;
1875 	int error;
1876 
1877 	ioat = arg1;
1878 	sbuf_new_for_sysctl(&sb, NULL, 16, req);
1879 
1880 	if (ioat->stats.interrupts == 0) {
1881 		sbuf_printf(&sb, "NaN");
1882 		goto out;
1883 	}
1884 	rate = ioat->stats.descriptors_processed * factor /
1885 	    ioat->stats.interrupts;
1886 	sbuf_printf(&sb, "%ju.%." PRECISION "ju", rate / factor,
1887 	    rate % factor);
1888 #undef	PRECISION
1889 out:
1890 	error = sbuf_finish(&sb);
1891 	sbuf_delete(&sb);
1892 	if (error != 0 || req->newptr == NULL)
1893 		return (error);
1894 	return (EINVAL);
1895 }
1896 
1897 static int
1898 sysctl_handle_reset(SYSCTL_HANDLER_ARGS)
1899 {
1900 	struct ioat_softc *ioat;
1901 	int error, arg;
1902 
1903 	ioat = arg1;
1904 
1905 	arg = 0;
1906 	error = SYSCTL_OUT(req, &arg, sizeof(arg));
1907 	if (error != 0 || req->newptr == NULL)
1908 		return (error);
1909 
1910 	error = SYSCTL_IN(req, &arg, sizeof(arg));
1911 	if (error != 0)
1912 		return (error);
1913 
1914 	if (arg != 0)
1915 		error = ioat_reset_hw(ioat);
1916 
1917 	return (error);
1918 }
1919 
1920 static void
1921 dump_descriptor(void *hw_desc)
1922 {
1923 	int i, j;
1924 
1925 	for (i = 0; i < 2; i++) {
1926 		for (j = 0; j < 8; j++)
1927 			printf("%08x ", ((uint32_t *)hw_desc)[i * 8 + j]);
1928 		printf("\n");
1929 	}
1930 }
1931 
1932 static void
1933 ioat_setup_sysctl(device_t device)
1934 {
1935 	struct sysctl_oid_list *par, *statpar, *state, *hammer;
1936 	struct sysctl_ctx_list *ctx;
1937 	struct sysctl_oid *tree, *tmp;
1938 	struct ioat_softc *ioat;
1939 
1940 	ioat = DEVICE2SOFTC(device);
1941 	ctx = device_get_sysctl_ctx(device);
1942 	tree = device_get_sysctl_tree(device);
1943 	par = SYSCTL_CHILDREN(tree);
1944 
1945 	SYSCTL_ADD_INT(ctx, par, OID_AUTO, "version", CTLFLAG_RD,
1946 	    &ioat->version, 0, "HW version (0xMM form)");
1947 	SYSCTL_ADD_UINT(ctx, par, OID_AUTO, "max_xfer_size", CTLFLAG_RD,
1948 	    &ioat->max_xfer_size, 0, "HW maximum transfer size");
1949 	SYSCTL_ADD_INT(ctx, par, OID_AUTO, "intrdelay_supported", CTLFLAG_RD,
1950 	    &ioat->intrdelay_supported, 0, "Is INTRDELAY supported");
1951 	SYSCTL_ADD_U16(ctx, par, OID_AUTO, "intrdelay_max", CTLFLAG_RD,
1952 	    &ioat->intrdelay_max, 0,
1953 	    "Maximum configurable INTRDELAY on this channel (microseconds)");
1954 
1955 	tmp = SYSCTL_ADD_NODE(ctx, par, OID_AUTO, "state",
1956 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "IOAT channel internal state");
1957 	state = SYSCTL_CHILDREN(tmp);
1958 
1959 	SYSCTL_ADD_UINT(ctx, state, OID_AUTO, "ring_size_order", CTLFLAG_RD,
1960 	    &ioat->ring_size_order, 0, "SW descriptor ring size order");
1961 	SYSCTL_ADD_UINT(ctx, state, OID_AUTO, "head", CTLFLAG_RD, &ioat->head,
1962 	    0, "SW descriptor head pointer index");
1963 	SYSCTL_ADD_UINT(ctx, state, OID_AUTO, "tail", CTLFLAG_RD, &ioat->tail,
1964 	    0, "SW descriptor tail pointer index");
1965 
1966 	SYSCTL_ADD_UQUAD(ctx, state, OID_AUTO, "last_completion", CTLFLAG_RD,
1967 	    ioat->comp_update, "HW addr of last completion");
1968 
1969 	SYSCTL_ADD_INT(ctx, state, OID_AUTO, "is_submitter_processing",
1970 	    CTLFLAG_RD, &ioat->is_submitter_processing, 0,
1971 	    "submitter processing");
1972 
1973 	SYSCTL_ADD_PROC(ctx, state, OID_AUTO, "chansts",
1974 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, ioat, 0,
1975 	    sysctl_handle_chansts, "A", "String of the channel status");
1976 
1977 	SYSCTL_ADD_U16(ctx, state, OID_AUTO, "intrdelay", CTLFLAG_RD,
1978 	    &ioat->cached_intrdelay, 0,
1979 	    "Current INTRDELAY on this channel (cached, microseconds)");
1980 
1981 	tmp = SYSCTL_ADD_NODE(ctx, par, OID_AUTO, "hammer",
1982 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
1983 	    "Big hammers (mostly for testing)");
1984 	hammer = SYSCTL_CHILDREN(tmp);
1985 
1986 	SYSCTL_ADD_PROC(ctx, hammer, OID_AUTO, "force_hw_reset",
1987 	    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, ioat, 0,
1988 	    sysctl_handle_reset, "I", "Set to non-zero to reset the hardware");
1989 
1990 	tmp = SYSCTL_ADD_NODE(ctx, par, OID_AUTO, "stats",
1991 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "IOAT channel statistics");
1992 	statpar = SYSCTL_CHILDREN(tmp);
1993 
1994 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "interrupts",
1995 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.interrupts,
1996 	    "Number of interrupts processed on this channel");
1997 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "descriptors",
1998 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.descriptors_processed,
1999 	    "Number of descriptors processed on this channel");
2000 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "submitted",
2001 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.descriptors_submitted,
2002 	    "Number of descriptors submitted to this channel");
2003 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "errored",
2004 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.descriptors_error,
2005 	    "Number of descriptors failed by channel errors");
2006 	SYSCTL_ADD_U32(ctx, statpar, OID_AUTO, "halts",
2007 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.channel_halts, 0,
2008 	    "Number of times the channel has halted");
2009 	SYSCTL_ADD_U32(ctx, statpar, OID_AUTO, "last_halt_chanerr",
2010 	    CTLFLAG_RW | CTLFLAG_STATS, &ioat->stats.last_halt_chanerr, 0,
2011 	    "The raw CHANERR when the channel was last halted");
2012 
2013 	SYSCTL_ADD_PROC(ctx, statpar, OID_AUTO, "desc_per_interrupt",
2014 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, ioat, 0,
2015 	    sysctl_handle_dpi, "A", "Descriptors per interrupt");
2016 }
2017 
2018 static void
2019 ioat_get(struct ioat_softc *ioat)
2020 {
2021 
2022 	mtx_assert(&ioat->submit_lock, MA_OWNED);
2023 	KASSERT(ioat->refcnt < UINT32_MAX, ("refcnt overflow"));
2024 
2025 	ioat->refcnt++;
2026 }
2027 
2028 static void
2029 ioat_put(struct ioat_softc *ioat)
2030 {
2031 
2032 	mtx_assert(&ioat->submit_lock, MA_OWNED);
2033 	KASSERT(ioat->refcnt >= 1, ("refcnt error"));
2034 
2035 	if (--ioat->refcnt == 0)
2036 		wakeup(&ioat->refcnt);
2037 }
2038 
2039 static void
2040 ioat_drain_locked(struct ioat_softc *ioat)
2041 {
2042 
2043 	mtx_assert(&ioat->submit_lock, MA_OWNED);
2044 
2045 	while (ioat->refcnt > 0)
2046 		msleep(&ioat->refcnt, &ioat->submit_lock, 0, "ioat_drain", 0);
2047 }
2048 
2049 #ifdef DDB
2050 #define	_db_show_lock(lo)	LOCK_CLASS(lo)->lc_ddb_show(lo)
2051 #define	db_show_lock(lk)	_db_show_lock(&(lk)->lock_object)
2052 DB_SHOW_COMMAND(ioat, db_show_ioat)
2053 {
2054 	struct ioat_softc *sc;
2055 	unsigned idx;
2056 
2057 	if (!have_addr)
2058 		goto usage;
2059 	idx = (unsigned)addr;
2060 	if (idx >= ioat_channel_index)
2061 		goto usage;
2062 
2063 	sc = ioat_channel[idx];
2064 	db_printf("ioat softc at %p\n", sc);
2065 	if (sc == NULL)
2066 		return;
2067 
2068 	db_printf(" version: %d\n", sc->version);
2069 	db_printf(" chan_idx: %u\n", sc->chan_idx);
2070 	db_printf(" submit_lock: ");
2071 	db_show_lock(&sc->submit_lock);
2072 
2073 	db_printf(" capabilities: %b\n", (int)sc->capabilities,
2074 	    IOAT_DMACAP_STR);
2075 	db_printf(" cached_intrdelay: %u\n", sc->cached_intrdelay);
2076 	db_printf(" *comp_update: 0x%jx\n", (uintmax_t)*sc->comp_update);
2077 
2078 	db_printf(" poll_timer:\n");
2079 	db_printf("  c_time: %ju\n", (uintmax_t)sc->poll_timer.c_time);
2080 	db_printf("  c_arg: %p\n", sc->poll_timer.c_arg);
2081 	db_printf("  c_func: %p\n", sc->poll_timer.c_func);
2082 	db_printf("  c_lock: %p\n", sc->poll_timer.c_lock);
2083 	db_printf("  c_flags: 0x%x\n", (unsigned)sc->poll_timer.c_flags);
2084 
2085 	db_printf(" quiescing: %d\n", (int)sc->quiescing);
2086 	db_printf(" destroying: %d\n", (int)sc->destroying);
2087 	db_printf(" is_submitter_processing: %d\n",
2088 	    (int)sc->is_submitter_processing);
2089 	db_printf(" intrdelay_supported: %d\n", (int)sc->intrdelay_supported);
2090 	db_printf(" resetting: %d\n", (int)sc->resetting);
2091 
2092 	db_printf(" head: %u\n", sc->head);
2093 	db_printf(" tail: %u\n", sc->tail);
2094 	db_printf(" ring_size_order: %u\n", sc->ring_size_order);
2095 	db_printf(" last_seen: 0x%lx\n", sc->last_seen);
2096 	db_printf(" ring: %p\n", sc->ring);
2097 	db_printf(" descriptors: %p\n", sc->hw_desc_ring);
2098 	db_printf(" descriptors (phys): 0x%jx\n",
2099 	    (uintmax_t)sc->hw_desc_bus_addr);
2100 
2101 	db_printf("  ring[%u] (tail):\n", sc->tail %
2102 	    (1 << sc->ring_size_order));
2103 	db_printf("   id: %u\n", ioat_get_ring_entry(sc, sc->tail)->id);
2104 	db_printf("   addr: 0x%lx\n",
2105 	    RING_PHYS_ADDR(sc, sc->tail));
2106 	db_printf("   next: 0x%lx\n",
2107 	     ioat_get_descriptor(sc, sc->tail)->generic.next);
2108 
2109 	db_printf("  ring[%u] (head - 1):\n", (sc->head - 1) %
2110 	    (1 << sc->ring_size_order));
2111 	db_printf("   id: %u\n", ioat_get_ring_entry(sc, sc->head - 1)->id);
2112 	db_printf("   addr: 0x%lx\n",
2113 	    RING_PHYS_ADDR(sc, sc->head - 1));
2114 	db_printf("   next: 0x%lx\n",
2115 	     ioat_get_descriptor(sc, sc->head - 1)->generic.next);
2116 
2117 	db_printf("  ring[%u] (head):\n", (sc->head) %
2118 	    (1 << sc->ring_size_order));
2119 	db_printf("   id: %u\n", ioat_get_ring_entry(sc, sc->head)->id);
2120 	db_printf("   addr: 0x%lx\n",
2121 	    RING_PHYS_ADDR(sc, sc->head));
2122 	db_printf("   next: 0x%lx\n",
2123 	     ioat_get_descriptor(sc, sc->head)->generic.next);
2124 
2125 	for (idx = 0; idx < (1 << sc->ring_size_order); idx++)
2126 		if ((*sc->comp_update & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_MASK)
2127 		    == RING_PHYS_ADDR(sc, idx))
2128 			db_printf("  ring[%u] == hardware tail\n", idx);
2129 
2130 	db_printf(" cleanup_lock: ");
2131 	db_show_lock(&sc->cleanup_lock);
2132 
2133 	db_printf(" refcnt: %u\n", sc->refcnt);
2134 	db_printf(" stats:\n");
2135 	db_printf("  interrupts: %lu\n", sc->stats.interrupts);
2136 	db_printf("  descriptors_processed: %lu\n", sc->stats.descriptors_processed);
2137 	db_printf("  descriptors_error: %lu\n", sc->stats.descriptors_error);
2138 	db_printf("  descriptors_submitted: %lu\n", sc->stats.descriptors_submitted);
2139 
2140 	db_printf("  channel_halts: %u\n", sc->stats.channel_halts);
2141 	db_printf("  last_halt_chanerr: %u\n", sc->stats.last_halt_chanerr);
2142 
2143 	if (db_pager_quit)
2144 		return;
2145 
2146 	db_printf(" hw status:\n");
2147 	db_printf("  status: 0x%lx\n", ioat_get_chansts(sc));
2148 	db_printf("  chanctrl: 0x%x\n",
2149 	    (unsigned)ioat_read_2(sc, IOAT_CHANCTRL_OFFSET));
2150 	db_printf("  chancmd: 0x%x\n",
2151 	    (unsigned)ioat_read_1(sc, IOAT_CHANCMD_OFFSET));
2152 	db_printf("  dmacount: 0x%x\n",
2153 	    (unsigned)ioat_read_2(sc, IOAT_DMACOUNT_OFFSET));
2154 	db_printf("  chainaddr: 0x%lx\n",
2155 	    ioat_read_double_4(sc, IOAT_CHAINADDR_OFFSET_LOW));
2156 	db_printf("  chancmp: 0x%lx\n",
2157 	    ioat_read_double_4(sc, IOAT_CHANCMP_OFFSET_LOW));
2158 	db_printf("  chanerr: %b\n",
2159 	    (int)ioat_read_4(sc, IOAT_CHANERR_OFFSET), IOAT_CHANERR_STR);
2160 	return;
2161 usage:
2162 	db_printf("usage: show ioat <0-%u>\n", ioat_channel_index);
2163 	return;
2164 }
2165 #endif /* DDB */
2166