xref: /freebsd/sys/dev/ioat/ioat.c (revision f3aff7c91bd451d300ffd37ddce5a1fdbe802123)
1 /*-
2  * Copyright (C) 2012 Intel Corporation
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include "opt_ddb.h"
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/bus.h>
35 #include <sys/conf.h>
36 #include <sys/fail.h>
37 #include <sys/ioccom.h>
38 #include <sys/kernel.h>
39 #include <sys/lock.h>
40 #include <sys/malloc.h>
41 #include <sys/module.h>
42 #include <sys/mutex.h>
43 #include <sys/rman.h>
44 #include <sys/sbuf.h>
45 #include <sys/sysctl.h>
46 #include <sys/taskqueue.h>
47 #include <sys/time.h>
48 #include <dev/pci/pcireg.h>
49 #include <dev/pci/pcivar.h>
50 #include <machine/bus.h>
51 #include <machine/resource.h>
52 #include <machine/stdarg.h>
53 
54 #ifdef DDB
55 #include <ddb/ddb.h>
56 #endif
57 
58 #include "ioat.h"
59 #include "ioat_hw.h"
60 #include "ioat_internal.h"
61 
62 #ifndef	BUS_SPACE_MAXADDR_40BIT
63 #define	BUS_SPACE_MAXADDR_40BIT	0xFFFFFFFFFFULL
64 #endif
65 #define	IOAT_REFLK	(&ioat->submit_lock)
66 
67 static int ioat_probe(device_t device);
68 static int ioat_attach(device_t device);
69 static int ioat_detach(device_t device);
70 static int ioat_setup_intr(struct ioat_softc *ioat);
71 static int ioat_teardown_intr(struct ioat_softc *ioat);
72 static int ioat3_attach(device_t device);
73 static int ioat_start_channel(struct ioat_softc *ioat);
74 static int ioat_map_pci_bar(struct ioat_softc *ioat);
75 static void ioat_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nseg,
76     int error);
77 static void ioat_interrupt_handler(void *arg);
78 static boolean_t ioat_model_resets_msix(struct ioat_softc *ioat);
79 static int chanerr_to_errno(uint32_t);
80 static void ioat_process_events(struct ioat_softc *ioat);
81 static inline uint32_t ioat_get_active(struct ioat_softc *ioat);
82 static inline uint32_t ioat_get_ring_space(struct ioat_softc *ioat);
83 static void ioat_free_ring(struct ioat_softc *, uint32_t size,
84     struct ioat_descriptor *);
85 static int ioat_reserve_space(struct ioat_softc *, uint32_t, int mflags);
86 static union ioat_hw_descriptor *ioat_get_descriptor(struct ioat_softc *,
87     uint32_t index);
88 static struct ioat_descriptor *ioat_get_ring_entry(struct ioat_softc *,
89     uint32_t index);
90 static void ioat_halted_debug(struct ioat_softc *, uint32_t);
91 static void ioat_poll_timer_callback(void *arg);
92 static void dump_descriptor(void *hw_desc);
93 static void ioat_submit_single(struct ioat_softc *ioat);
94 static void ioat_comp_update_map(void *arg, bus_dma_segment_t *seg, int nseg,
95     int error);
96 static int ioat_reset_hw(struct ioat_softc *ioat);
97 static void ioat_reset_hw_task(void *, int);
98 static void ioat_setup_sysctl(device_t device);
99 static int sysctl_handle_reset(SYSCTL_HANDLER_ARGS);
100 static inline struct ioat_softc *ioat_get(struct ioat_softc *,
101     enum ioat_ref_kind);
102 static inline void ioat_put(struct ioat_softc *, enum ioat_ref_kind);
103 static inline void _ioat_putn(struct ioat_softc *, uint32_t,
104     enum ioat_ref_kind, boolean_t);
105 static inline void ioat_putn(struct ioat_softc *, uint32_t,
106     enum ioat_ref_kind);
107 static inline void ioat_putn_locked(struct ioat_softc *, uint32_t,
108     enum ioat_ref_kind);
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, 0, "ioat node");
119 
120 static int g_force_legacy_interrupts;
121 SYSCTL_INT(_hw_ioat, OID_AUTO, force_legacy_interrupts, CTLFLAG_RDTUN,
122     &g_force_legacy_interrupts, 0, "Set to non-zero to force MSI-X disabled");
123 
124 int g_ioat_debug_level = 0;
125 SYSCTL_INT(_hw_ioat, OID_AUTO, debug_level, CTLFLAG_RWTUN, &g_ioat_debug_level,
126     0, "Set log level (0-3) for ioat(4). Higher is more verbose.");
127 
128 unsigned g_ioat_ring_order = 13;
129 SYSCTL_UINT(_hw_ioat, OID_AUTO, ring_order, CTLFLAG_RDTUN, &g_ioat_ring_order,
130     0, "Set IOAT ring order.  (1 << this) == ring size.");
131 
132 /*
133  * OS <-> Driver interface structures
134  */
135 static device_method_t ioat_pci_methods[] = {
136 	/* Device interface */
137 	DEVMETHOD(device_probe,     ioat_probe),
138 	DEVMETHOD(device_attach,    ioat_attach),
139 	DEVMETHOD(device_detach,    ioat_detach),
140 	DEVMETHOD_END
141 };
142 
143 static driver_t ioat_pci_driver = {
144 	"ioat",
145 	ioat_pci_methods,
146 	sizeof(struct ioat_softc),
147 };
148 
149 static devclass_t ioat_devclass;
150 DRIVER_MODULE(ioat, pci, ioat_pci_driver, ioat_devclass, 0, 0);
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 
161 static struct _pcsid
162 {
163 	u_int32_t   type;
164 	const char  *desc;
165 } pci_ids[] = {
166 	{ 0x34308086, "TBG IOAT Ch0" },
167 	{ 0x34318086, "TBG IOAT Ch1" },
168 	{ 0x34328086, "TBG IOAT Ch2" },
169 	{ 0x34338086, "TBG IOAT Ch3" },
170 	{ 0x34298086, "TBG IOAT Ch4" },
171 	{ 0x342a8086, "TBG IOAT Ch5" },
172 	{ 0x342b8086, "TBG IOAT Ch6" },
173 	{ 0x342c8086, "TBG IOAT Ch7" },
174 
175 	{ 0x37108086, "JSF IOAT Ch0" },
176 	{ 0x37118086, "JSF IOAT Ch1" },
177 	{ 0x37128086, "JSF IOAT Ch2" },
178 	{ 0x37138086, "JSF IOAT Ch3" },
179 	{ 0x37148086, "JSF IOAT Ch4" },
180 	{ 0x37158086, "JSF IOAT Ch5" },
181 	{ 0x37168086, "JSF IOAT Ch6" },
182 	{ 0x37178086, "JSF IOAT Ch7" },
183 	{ 0x37188086, "JSF IOAT Ch0 (RAID)" },
184 	{ 0x37198086, "JSF IOAT Ch1 (RAID)" },
185 
186 	{ 0x3c208086, "SNB IOAT Ch0" },
187 	{ 0x3c218086, "SNB IOAT Ch1" },
188 	{ 0x3c228086, "SNB IOAT Ch2" },
189 	{ 0x3c238086, "SNB IOAT Ch3" },
190 	{ 0x3c248086, "SNB IOAT Ch4" },
191 	{ 0x3c258086, "SNB IOAT Ch5" },
192 	{ 0x3c268086, "SNB IOAT Ch6" },
193 	{ 0x3c278086, "SNB IOAT Ch7" },
194 	{ 0x3c2e8086, "SNB IOAT Ch0 (RAID)" },
195 	{ 0x3c2f8086, "SNB IOAT Ch1 (RAID)" },
196 
197 	{ 0x0e208086, "IVB IOAT Ch0" },
198 	{ 0x0e218086, "IVB IOAT Ch1" },
199 	{ 0x0e228086, "IVB IOAT Ch2" },
200 	{ 0x0e238086, "IVB IOAT Ch3" },
201 	{ 0x0e248086, "IVB IOAT Ch4" },
202 	{ 0x0e258086, "IVB IOAT Ch5" },
203 	{ 0x0e268086, "IVB IOAT Ch6" },
204 	{ 0x0e278086, "IVB IOAT Ch7" },
205 	{ 0x0e2e8086, "IVB IOAT Ch0 (RAID)" },
206 	{ 0x0e2f8086, "IVB IOAT Ch1 (RAID)" },
207 
208 	{ 0x2f208086, "HSW IOAT Ch0" },
209 	{ 0x2f218086, "HSW IOAT Ch1" },
210 	{ 0x2f228086, "HSW IOAT Ch2" },
211 	{ 0x2f238086, "HSW IOAT Ch3" },
212 	{ 0x2f248086, "HSW IOAT Ch4" },
213 	{ 0x2f258086, "HSW IOAT Ch5" },
214 	{ 0x2f268086, "HSW IOAT Ch6" },
215 	{ 0x2f278086, "HSW IOAT Ch7" },
216 	{ 0x2f2e8086, "HSW IOAT Ch0 (RAID)" },
217 	{ 0x2f2f8086, "HSW IOAT Ch1 (RAID)" },
218 
219 	{ 0x0c508086, "BWD IOAT Ch0" },
220 	{ 0x0c518086, "BWD IOAT Ch1" },
221 	{ 0x0c528086, "BWD IOAT Ch2" },
222 	{ 0x0c538086, "BWD IOAT Ch3" },
223 
224 	{ 0x6f508086, "BDXDE IOAT Ch0" },
225 	{ 0x6f518086, "BDXDE IOAT Ch1" },
226 	{ 0x6f528086, "BDXDE IOAT Ch2" },
227 	{ 0x6f538086, "BDXDE IOAT Ch3" },
228 
229 	{ 0x6f208086, "BDX IOAT Ch0" },
230 	{ 0x6f218086, "BDX IOAT Ch1" },
231 	{ 0x6f228086, "BDX IOAT Ch2" },
232 	{ 0x6f238086, "BDX IOAT Ch3" },
233 	{ 0x6f248086, "BDX IOAT Ch4" },
234 	{ 0x6f258086, "BDX IOAT Ch5" },
235 	{ 0x6f268086, "BDX IOAT Ch6" },
236 	{ 0x6f278086, "BDX IOAT Ch7" },
237 	{ 0x6f2e8086, "BDX IOAT Ch0 (RAID)" },
238 	{ 0x6f2f8086, "BDX IOAT Ch1 (RAID)" },
239 
240 	{ 0x20218086, "SKX IOAT" },
241 };
242 
243 MODULE_PNP_INFO("W32:vendor/device;D:human", pci, ioat, pci_ids,
244     sizeof(pci_ids[0]), nitems(pci_ids));
245 
246 /*
247  * OS <-> Driver linkage functions
248  */
249 static int
250 ioat_probe(device_t device)
251 {
252 	struct _pcsid *ep;
253 	u_int32_t type;
254 
255 	type = pci_get_devid(device);
256 	for (ep = pci_ids; ep < &pci_ids[nitems(pci_ids)]; ep++) {
257 		if (ep->type == type) {
258 			device_set_desc(device, ep->desc);
259 			return (0);
260 		}
261 	}
262 	return (ENXIO);
263 }
264 
265 static int
266 ioat_attach(device_t device)
267 {
268 	struct ioat_softc *ioat;
269 	int error;
270 
271 	ioat = DEVICE2SOFTC(device);
272 	ioat->device = device;
273 
274 	error = ioat_map_pci_bar(ioat);
275 	if (error != 0)
276 		goto err;
277 
278 	ioat->version = ioat_read_cbver(ioat);
279 	if (ioat->version < IOAT_VER_3_0) {
280 		error = ENODEV;
281 		goto err;
282 	}
283 
284 	error = ioat3_attach(device);
285 	if (error != 0)
286 		goto err;
287 
288 	error = pci_enable_busmaster(device);
289 	if (error != 0)
290 		goto err;
291 
292 	error = ioat_setup_intr(ioat);
293 	if (error != 0)
294 		goto err;
295 
296 	error = ioat_reset_hw(ioat);
297 	if (error != 0)
298 		goto err;
299 
300 	ioat_process_events(ioat);
301 	ioat_setup_sysctl(device);
302 
303 	ioat->chan_idx = ioat_channel_index;
304 	ioat_channel[ioat_channel_index++] = ioat;
305 	ioat_test_attach();
306 
307 err:
308 	if (error != 0)
309 		ioat_detach(device);
310 	return (error);
311 }
312 
313 static int
314 ioat_detach(device_t device)
315 {
316 	struct ioat_softc *ioat;
317 
318 	ioat = DEVICE2SOFTC(device);
319 
320 	ioat_test_detach();
321 	taskqueue_drain(taskqueue_thread, &ioat->reset_task);
322 
323 	mtx_lock(IOAT_REFLK);
324 	ioat->quiescing = TRUE;
325 	ioat->destroying = TRUE;
326 	wakeup(&ioat->quiescing);
327 	wakeup(&ioat->resetting);
328 
329 	ioat_channel[ioat->chan_idx] = NULL;
330 
331 	ioat_drain_locked(ioat);
332 	mtx_unlock(IOAT_REFLK);
333 
334 	ioat_teardown_intr(ioat);
335 	callout_drain(&ioat->poll_timer);
336 
337 	pci_disable_busmaster(device);
338 
339 	if (ioat->pci_resource != NULL)
340 		bus_release_resource(device, SYS_RES_MEMORY,
341 		    ioat->pci_resource_id, ioat->pci_resource);
342 
343 	if (ioat->ring != NULL)
344 		ioat_free_ring(ioat, 1 << ioat->ring_size_order, ioat->ring);
345 
346 	if (ioat->comp_update != NULL) {
347 		bus_dmamap_unload(ioat->comp_update_tag, ioat->comp_update_map);
348 		bus_dmamem_free(ioat->comp_update_tag, ioat->comp_update,
349 		    ioat->comp_update_map);
350 		bus_dma_tag_destroy(ioat->comp_update_tag);
351 	}
352 
353 	if (ioat->hw_desc_ring != NULL) {
354 		bus_dmamap_unload(ioat->hw_desc_tag, ioat->hw_desc_map);
355 		bus_dmamem_free(ioat->hw_desc_tag, ioat->hw_desc_ring,
356 		    ioat->hw_desc_map);
357 		bus_dma_tag_destroy(ioat->hw_desc_tag);
358 	}
359 
360 	return (0);
361 }
362 
363 static int
364 ioat_teardown_intr(struct ioat_softc *ioat)
365 {
366 
367 	if (ioat->tag != NULL)
368 		bus_teardown_intr(ioat->device, ioat->res, ioat->tag);
369 
370 	if (ioat->res != NULL)
371 		bus_release_resource(ioat->device, SYS_RES_IRQ,
372 		    rman_get_rid(ioat->res), ioat->res);
373 
374 	pci_release_msi(ioat->device);
375 	return (0);
376 }
377 
378 static int
379 ioat_start_channel(struct ioat_softc *ioat)
380 {
381 	struct ioat_dma_hw_descriptor *hw_desc;
382 	struct ioat_descriptor *desc;
383 	struct bus_dmadesc *dmadesc;
384 	uint64_t status;
385 	uint32_t chanerr;
386 	int i;
387 
388 	ioat_acquire(&ioat->dmaengine);
389 
390 	/* Submit 'NULL' operation manually to avoid quiescing flag */
391 	desc = ioat_get_ring_entry(ioat, ioat->head);
392 	hw_desc = &ioat_get_descriptor(ioat, ioat->head)->dma;
393 	dmadesc = &desc->bus_dmadesc;
394 
395 	dmadesc->callback_fn = NULL;
396 	dmadesc->callback_arg = NULL;
397 
398 	hw_desc->u.control_raw = 0;
399 	hw_desc->u.control_generic.op = IOAT_OP_COPY;
400 	hw_desc->u.control_generic.completion_update = 1;
401 	hw_desc->size = 8;
402 	hw_desc->src_addr = 0;
403 	hw_desc->dest_addr = 0;
404 	hw_desc->u.control.null = 1;
405 
406 	ioat_submit_single(ioat);
407 	ioat_release(&ioat->dmaengine);
408 
409 	for (i = 0; i < 100; i++) {
410 		DELAY(1);
411 		status = ioat_get_chansts(ioat);
412 		if (is_ioat_idle(status))
413 			return (0);
414 	}
415 
416 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
417 	ioat_log_message(0, "could not start channel: "
418 	    "status = %#jx error = %b\n", (uintmax_t)status, (int)chanerr,
419 	    IOAT_CHANERR_STR);
420 	return (ENXIO);
421 }
422 
423 /*
424  * Initialize Hardware
425  */
426 static int
427 ioat3_attach(device_t device)
428 {
429 	struct ioat_softc *ioat;
430 	struct ioat_descriptor *ring;
431 	struct ioat_dma_hw_descriptor *dma_hw_desc;
432 	void *hw_desc;
433 	size_t ringsz;
434 	int i, num_descriptors;
435 	int error;
436 	uint8_t xfercap;
437 
438 	error = 0;
439 	ioat = DEVICE2SOFTC(device);
440 	ioat->capabilities = ioat_read_dmacapability(ioat);
441 
442 	ioat_log_message(0, "Capabilities: %b\n", (int)ioat->capabilities,
443 	    IOAT_DMACAP_STR);
444 
445 	xfercap = ioat_read_xfercap(ioat);
446 	ioat->max_xfer_size = 1 << xfercap;
447 
448 	ioat->intrdelay_supported = (ioat_read_2(ioat, IOAT_INTRDELAY_OFFSET) &
449 	    IOAT_INTRDELAY_SUPPORTED) != 0;
450 	if (ioat->intrdelay_supported)
451 		ioat->intrdelay_max = IOAT_INTRDELAY_US_MASK;
452 
453 	/* TODO: need to check DCA here if we ever do XOR/PQ */
454 
455 	mtx_init(&ioat->submit_lock, "ioat_submit", NULL, MTX_DEF);
456 	mtx_init(&ioat->cleanup_lock, "ioat_cleanup", NULL, MTX_DEF);
457 	callout_init(&ioat->poll_timer, 1);
458 	TASK_INIT(&ioat->reset_task, 0, ioat_reset_hw_task, ioat);
459 
460 	/* Establish lock order for Witness */
461 	mtx_lock(&ioat->submit_lock);
462 	mtx_lock(&ioat->cleanup_lock);
463 	mtx_unlock(&ioat->cleanup_lock);
464 	mtx_unlock(&ioat->submit_lock);
465 
466 	ioat->is_submitter_processing = FALSE;
467 	ioat->is_completion_pending = FALSE;
468 	ioat->is_reset_pending = FALSE;
469 	ioat->is_channel_running = FALSE;
470 
471 	bus_dma_tag_create(bus_get_dma_tag(ioat->device), sizeof(uint64_t), 0x0,
472 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
473 	    sizeof(uint64_t), 1, sizeof(uint64_t), 0, NULL, NULL,
474 	    &ioat->comp_update_tag);
475 
476 	error = bus_dmamem_alloc(ioat->comp_update_tag,
477 	    (void **)&ioat->comp_update, BUS_DMA_ZERO, &ioat->comp_update_map);
478 	if (ioat->comp_update == NULL)
479 		return (ENOMEM);
480 
481 	error = bus_dmamap_load(ioat->comp_update_tag, ioat->comp_update_map,
482 	    ioat->comp_update, sizeof(uint64_t), ioat_comp_update_map, ioat,
483 	    0);
484 	if (error != 0)
485 		return (error);
486 
487 	ioat->ring_size_order = g_ioat_ring_order;
488 	num_descriptors = 1 << ioat->ring_size_order;
489 	ringsz = sizeof(struct ioat_dma_hw_descriptor) * num_descriptors;
490 
491 	error = bus_dma_tag_create(bus_get_dma_tag(ioat->device),
492 	    2 * 1024 * 1024, 0x0, (bus_addr_t)BUS_SPACE_MAXADDR_40BIT,
493 	    BUS_SPACE_MAXADDR, NULL, NULL, ringsz, 1, ringsz, 0, NULL, NULL,
494 	    &ioat->hw_desc_tag);
495 	if (error != 0)
496 		return (error);
497 
498 	error = bus_dmamem_alloc(ioat->hw_desc_tag, &hw_desc,
499 	    BUS_DMA_ZERO | BUS_DMA_WAITOK, &ioat->hw_desc_map);
500 	if (error != 0)
501 		return (error);
502 
503 	error = bus_dmamap_load(ioat->hw_desc_tag, ioat->hw_desc_map, hw_desc,
504 	    ringsz, ioat_dmamap_cb, &ioat->hw_desc_bus_addr, BUS_DMA_WAITOK);
505 	if (error)
506 		return (error);
507 
508 	ioat->hw_desc_ring = hw_desc;
509 
510 	ioat->ring = malloc(num_descriptors * sizeof(*ring), M_IOAT,
511 	    M_ZERO | M_WAITOK);
512 
513 	ring = ioat->ring;
514 	for (i = 0; i < num_descriptors; i++) {
515 		memset(&ring[i].bus_dmadesc, 0, sizeof(ring[i].bus_dmadesc));
516 		ring[i].id = i;
517 	}
518 
519 	for (i = 0; i < num_descriptors; i++) {
520 		dma_hw_desc = &ioat->hw_desc_ring[i].dma;
521 		dma_hw_desc->next = RING_PHYS_ADDR(ioat, i + 1);
522 	}
523 
524 	ioat->head = ioat->hw_head = 0;
525 	ioat->tail = 0;
526 	ioat->last_seen = 0;
527 	*ioat->comp_update = 0;
528 	return (0);
529 }
530 
531 static int
532 ioat_map_pci_bar(struct ioat_softc *ioat)
533 {
534 
535 	ioat->pci_resource_id = PCIR_BAR(0);
536 	ioat->pci_resource = bus_alloc_resource_any(ioat->device,
537 	    SYS_RES_MEMORY, &ioat->pci_resource_id, RF_ACTIVE);
538 
539 	if (ioat->pci_resource == NULL) {
540 		ioat_log_message(0, "unable to allocate pci resource\n");
541 		return (ENODEV);
542 	}
543 
544 	ioat->pci_bus_tag = rman_get_bustag(ioat->pci_resource);
545 	ioat->pci_bus_handle = rman_get_bushandle(ioat->pci_resource);
546 	return (0);
547 }
548 
549 static void
550 ioat_comp_update_map(void *arg, bus_dma_segment_t *seg, int nseg, int error)
551 {
552 	struct ioat_softc *ioat = arg;
553 
554 	KASSERT(error == 0, ("%s: error:%d", __func__, error));
555 	ioat->comp_update_bus_addr = seg[0].ds_addr;
556 }
557 
558 static void
559 ioat_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nseg, int error)
560 {
561 	bus_addr_t *baddr;
562 
563 	KASSERT(error == 0, ("%s: error:%d", __func__, error));
564 	baddr = arg;
565 	*baddr = segs->ds_addr;
566 }
567 
568 /*
569  * Interrupt setup and handlers
570  */
571 static int
572 ioat_setup_intr(struct ioat_softc *ioat)
573 {
574 	uint32_t num_vectors;
575 	int error;
576 	boolean_t use_msix;
577 	boolean_t force_legacy_interrupts;
578 
579 	use_msix = FALSE;
580 	force_legacy_interrupts = FALSE;
581 
582 	if (!g_force_legacy_interrupts && pci_msix_count(ioat->device) >= 1) {
583 		num_vectors = 1;
584 		pci_alloc_msix(ioat->device, &num_vectors);
585 		if (num_vectors == 1)
586 			use_msix = TRUE;
587 	}
588 
589 	if (use_msix) {
590 		ioat->rid = 1;
591 		ioat->res = bus_alloc_resource_any(ioat->device, SYS_RES_IRQ,
592 		    &ioat->rid, RF_ACTIVE);
593 	} else {
594 		ioat->rid = 0;
595 		ioat->res = bus_alloc_resource_any(ioat->device, SYS_RES_IRQ,
596 		    &ioat->rid, RF_SHAREABLE | RF_ACTIVE);
597 	}
598 	if (ioat->res == NULL) {
599 		ioat_log_message(0, "bus_alloc_resource failed\n");
600 		return (ENOMEM);
601 	}
602 
603 	ioat->tag = NULL;
604 	error = bus_setup_intr(ioat->device, ioat->res, INTR_MPSAFE |
605 	    INTR_TYPE_MISC, NULL, ioat_interrupt_handler, ioat, &ioat->tag);
606 	if (error != 0) {
607 		ioat_log_message(0, "bus_setup_intr failed\n");
608 		return (error);
609 	}
610 
611 	ioat_write_intrctrl(ioat, IOAT_INTRCTRL_MASTER_INT_EN);
612 	return (0);
613 }
614 
615 static boolean_t
616 ioat_model_resets_msix(struct ioat_softc *ioat)
617 {
618 	u_int32_t pciid;
619 
620 	pciid = pci_get_devid(ioat->device);
621 	switch (pciid) {
622 		/* BWD: */
623 	case 0x0c508086:
624 	case 0x0c518086:
625 	case 0x0c528086:
626 	case 0x0c538086:
627 		/* BDXDE: */
628 	case 0x6f508086:
629 	case 0x6f518086:
630 	case 0x6f528086:
631 	case 0x6f538086:
632 		return (TRUE);
633 	}
634 
635 	return (FALSE);
636 }
637 
638 static void
639 ioat_interrupt_handler(void *arg)
640 {
641 	struct ioat_softc *ioat = arg;
642 
643 	ioat->stats.interrupts++;
644 	ioat_process_events(ioat);
645 }
646 
647 static int
648 chanerr_to_errno(uint32_t chanerr)
649 {
650 
651 	if (chanerr == 0)
652 		return (0);
653 	if ((chanerr & (IOAT_CHANERR_XSADDERR | IOAT_CHANERR_XDADDERR)) != 0)
654 		return (EFAULT);
655 	if ((chanerr & (IOAT_CHANERR_RDERR | IOAT_CHANERR_WDERR)) != 0)
656 		return (EIO);
657 	/* This one is probably our fault: */
658 	if ((chanerr & IOAT_CHANERR_NDADDERR) != 0)
659 		return (EIO);
660 	return (EIO);
661 }
662 
663 static void
664 ioat_process_events(struct ioat_softc *ioat)
665 {
666 	struct ioat_descriptor *desc;
667 	struct bus_dmadesc *dmadesc;
668 	uint64_t comp_update, status;
669 	uint32_t completed, chanerr;
670 	boolean_t pending;
671 	int error;
672 
673 	mtx_lock(&ioat->cleanup_lock);
674 
675 	/*
676 	 * Don't run while the hardware is being reset.  Reset is responsible
677 	 * for blocking new work and draining & completing existing work, so
678 	 * there is nothing to do until new work is queued after reset anyway.
679 	 */
680 	if (ioat->resetting_cleanup) {
681 		mtx_unlock(&ioat->cleanup_lock);
682 		return;
683 	}
684 
685 	completed = 0;
686 	comp_update = *ioat->comp_update;
687 	status = comp_update & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_MASK;
688 
689 	if (status < ioat->hw_desc_bus_addr ||
690 	    status >= ioat->hw_desc_bus_addr + (1 << ioat->ring_size_order) *
691 	    sizeof(struct ioat_generic_hw_descriptor))
692 		panic("Bogus completion address %jx (channel %u)",
693 		    (uintmax_t)status, ioat->chan_idx);
694 
695 	if (status == ioat->last_seen) {
696 		/*
697 		 * If we landed in process_events and nothing has been
698 		 * completed, check for a timeout due to channel halt.
699 		 */
700 		goto out;
701 	}
702 	CTR4(KTR_IOAT, "%s channel=%u hw_status=0x%lx last_seen=0x%lx",
703 	    __func__, ioat->chan_idx, comp_update, ioat->last_seen);
704 
705 	while (RING_PHYS_ADDR(ioat, ioat->tail - 1) != status) {
706 		desc = ioat_get_ring_entry(ioat, ioat->tail);
707 		dmadesc = &desc->bus_dmadesc;
708 		CTR5(KTR_IOAT, "channel=%u completing desc idx %u (%p) ok  cb %p(%p)",
709 		    ioat->chan_idx, ioat->tail, dmadesc, dmadesc->callback_fn,
710 		    dmadesc->callback_arg);
711 
712 		if (dmadesc->callback_fn != NULL)
713 			dmadesc->callback_fn(dmadesc->callback_arg, 0);
714 
715 		completed++;
716 		ioat->tail++;
717 	}
718 	CTR5(KTR_IOAT, "%s channel=%u head=%u tail=%u active=%u", __func__,
719 	    ioat->chan_idx, ioat->head, ioat->tail, ioat_get_active(ioat));
720 
721 	if (completed != 0) {
722 		ioat->last_seen = RING_PHYS_ADDR(ioat, ioat->tail - 1);
723 		ioat->stats.descriptors_processed += completed;
724 	}
725 
726 out:
727 	ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
728 
729 	/* Perform a racy check first; only take the locks if it passes. */
730 	pending = (ioat_get_active(ioat) != 0);
731 	if (!pending && ioat->is_completion_pending) {
732 		mtx_unlock(&ioat->cleanup_lock);
733 		mtx_lock(&ioat->submit_lock);
734 		mtx_lock(&ioat->cleanup_lock);
735 
736 		pending = (ioat_get_active(ioat) != 0);
737 		if (!pending && ioat->is_completion_pending) {
738 			ioat->is_completion_pending = FALSE;
739 			callout_stop(&ioat->poll_timer);
740 		}
741 		mtx_unlock(&ioat->submit_lock);
742 	}
743 	mtx_unlock(&ioat->cleanup_lock);
744 
745 	if (pending)
746 		callout_reset(&ioat->poll_timer, 1, ioat_poll_timer_callback,
747 		    ioat);
748 
749 	if (completed != 0) {
750 		ioat_putn(ioat, completed, IOAT_ACTIVE_DESCR_REF);
751 		wakeup(&ioat->tail);
752 	}
753 
754 	/*
755 	 * The device doesn't seem to reliably push suspend/halt statuses to
756 	 * the channel completion memory address, so poll the device register
757 	 * here.
758 	 */
759 	comp_update = ioat_get_chansts(ioat) & IOAT_CHANSTS_STATUS;
760 	if (!is_ioat_halted(comp_update) && !is_ioat_suspended(comp_update))
761 		return;
762 
763 	ioat->stats.channel_halts++;
764 
765 	/*
766 	 * Fatal programming error on this DMA channel.  Flush any outstanding
767 	 * work with error status and restart the engine.
768 	 */
769 	mtx_lock(&ioat->submit_lock);
770 	mtx_lock(&ioat->cleanup_lock);
771 	ioat->quiescing = TRUE;
772 	/*
773 	 * This is safe to do here because we have both locks and the submit
774 	 * queue is quiesced.  We know that we will drain all outstanding
775 	 * events, so ioat_reset_hw can't deadlock.  It is necessary to
776 	 * protect other ioat_process_event threads from racing ioat_reset_hw,
777 	 * reading an indeterminate hw state, and attempting to continue
778 	 * issuing completions.
779 	 */
780 	ioat->resetting_cleanup = TRUE;
781 
782 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
783 	if (1 <= g_ioat_debug_level)
784 		ioat_halted_debug(ioat, chanerr);
785 	ioat->stats.last_halt_chanerr = chanerr;
786 
787 	while (ioat_get_active(ioat) > 0) {
788 		desc = ioat_get_ring_entry(ioat, ioat->tail);
789 		dmadesc = &desc->bus_dmadesc;
790 		CTR5(KTR_IOAT, "channel=%u completing desc idx %u (%p) err cb %p(%p)",
791 		    ioat->chan_idx, ioat->tail, dmadesc, dmadesc->callback_fn,
792 		    dmadesc->callback_arg);
793 
794 		if (dmadesc->callback_fn != NULL)
795 			dmadesc->callback_fn(dmadesc->callback_arg,
796 			    chanerr_to_errno(chanerr));
797 
798 		ioat_putn_locked(ioat, 1, IOAT_ACTIVE_DESCR_REF);
799 		ioat->tail++;
800 		ioat->stats.descriptors_processed++;
801 		ioat->stats.descriptors_error++;
802 	}
803 	CTR5(KTR_IOAT, "%s channel=%u head=%u tail=%u active=%u", __func__,
804 	    ioat->chan_idx, ioat->head, ioat->tail, ioat_get_active(ioat));
805 
806 	if (ioat->is_completion_pending) {
807 		ioat->is_completion_pending = FALSE;
808 		callout_stop(&ioat->poll_timer);
809 	}
810 
811 	/* Clear error status */
812 	ioat_write_4(ioat, IOAT_CHANERR_OFFSET, chanerr);
813 
814 	mtx_unlock(&ioat->cleanup_lock);
815 	mtx_unlock(&ioat->submit_lock);
816 
817 	ioat_log_message(0, "Resetting channel to recover from error\n");
818 	error = taskqueue_enqueue(taskqueue_thread, &ioat->reset_task);
819 	KASSERT(error == 0,
820 	    ("%s: taskqueue_enqueue failed: %d", __func__, error));
821 }
822 
823 static void
824 ioat_reset_hw_task(void *ctx, int pending __unused)
825 {
826 	struct ioat_softc *ioat;
827 	int error;
828 
829 	ioat = ctx;
830 	ioat_log_message(1, "%s: Resetting channel\n", __func__);
831 
832 	error = ioat_reset_hw(ioat);
833 	KASSERT(error == 0, ("%s: reset failed: %d", __func__, error));
834 	(void)error;
835 }
836 
837 /*
838  * User API functions
839  */
840 unsigned
841 ioat_get_nchannels(void)
842 {
843 
844 	return (ioat_channel_index);
845 }
846 
847 bus_dmaengine_t
848 ioat_get_dmaengine(uint32_t index, int flags)
849 {
850 	struct ioat_softc *ioat;
851 
852 	KASSERT((flags & ~(M_NOWAIT | M_WAITOK)) == 0,
853 	    ("invalid flags: 0x%08x", flags));
854 	KASSERT((flags & (M_NOWAIT | M_WAITOK)) != (M_NOWAIT | M_WAITOK),
855 	    ("invalid wait | nowait"));
856 
857 	if (index >= ioat_channel_index)
858 		return (NULL);
859 
860 	ioat = ioat_channel[index];
861 	if (ioat == NULL || ioat->destroying)
862 		return (NULL);
863 
864 	if (ioat->quiescing) {
865 		if ((flags & M_NOWAIT) != 0)
866 			return (NULL);
867 
868 		mtx_lock(IOAT_REFLK);
869 		while (ioat->quiescing && !ioat->destroying)
870 			msleep(&ioat->quiescing, IOAT_REFLK, 0, "getdma", 0);
871 		mtx_unlock(IOAT_REFLK);
872 
873 		if (ioat->destroying)
874 			return (NULL);
875 	}
876 
877 	/*
878 	 * There's a race here between the quiescing check and HW reset or
879 	 * module destroy.
880 	 */
881 	return (&ioat_get(ioat, IOAT_DMAENGINE_REF)->dmaengine);
882 }
883 
884 void
885 ioat_put_dmaengine(bus_dmaengine_t dmaengine)
886 {
887 	struct ioat_softc *ioat;
888 
889 	ioat = to_ioat_softc(dmaengine);
890 	ioat_put(ioat, IOAT_DMAENGINE_REF);
891 }
892 
893 int
894 ioat_get_hwversion(bus_dmaengine_t dmaengine)
895 {
896 	struct ioat_softc *ioat;
897 
898 	ioat = to_ioat_softc(dmaengine);
899 	return (ioat->version);
900 }
901 
902 size_t
903 ioat_get_max_io_size(bus_dmaengine_t dmaengine)
904 {
905 	struct ioat_softc *ioat;
906 
907 	ioat = to_ioat_softc(dmaengine);
908 	return (ioat->max_xfer_size);
909 }
910 
911 uint32_t
912 ioat_get_capabilities(bus_dmaengine_t dmaengine)
913 {
914 	struct ioat_softc *ioat;
915 
916 	ioat = to_ioat_softc(dmaengine);
917 	return (ioat->capabilities);
918 }
919 
920 int
921 ioat_set_interrupt_coalesce(bus_dmaengine_t dmaengine, uint16_t delay)
922 {
923 	struct ioat_softc *ioat;
924 
925 	ioat = to_ioat_softc(dmaengine);
926 	if (!ioat->intrdelay_supported)
927 		return (ENODEV);
928 	if (delay > ioat->intrdelay_max)
929 		return (ERANGE);
930 
931 	ioat_write_2(ioat, IOAT_INTRDELAY_OFFSET, delay);
932 	ioat->cached_intrdelay =
933 	    ioat_read_2(ioat, IOAT_INTRDELAY_OFFSET) & IOAT_INTRDELAY_US_MASK;
934 	return (0);
935 }
936 
937 uint16_t
938 ioat_get_max_coalesce_period(bus_dmaengine_t dmaengine)
939 {
940 	struct ioat_softc *ioat;
941 
942 	ioat = to_ioat_softc(dmaengine);
943 	return (ioat->intrdelay_max);
944 }
945 
946 void
947 ioat_acquire(bus_dmaengine_t dmaengine)
948 {
949 	struct ioat_softc *ioat;
950 
951 	ioat = to_ioat_softc(dmaengine);
952 	mtx_lock(&ioat->submit_lock);
953 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
954 	ioat->acq_head = ioat->head;
955 }
956 
957 int
958 ioat_acquire_reserve(bus_dmaengine_t dmaengine, unsigned n, int mflags)
959 {
960 	struct ioat_softc *ioat;
961 	int error;
962 
963 	ioat = to_ioat_softc(dmaengine);
964 	ioat_acquire(dmaengine);
965 
966 	error = ioat_reserve_space(ioat, n, mflags);
967 	if (error != 0)
968 		ioat_release(dmaengine);
969 	return (error);
970 }
971 
972 void
973 ioat_release(bus_dmaengine_t dmaengine)
974 {
975 	struct ioat_softc *ioat;
976 
977 	ioat = to_ioat_softc(dmaengine);
978 	CTR4(KTR_IOAT, "%s channel=%u dispatch1 hw_head=%u head=%u", __func__,
979 	    ioat->chan_idx, ioat->hw_head & UINT16_MAX, ioat->head);
980 	KFAIL_POINT_CODE(DEBUG_FP, ioat_release, /* do nothing */);
981 	CTR4(KTR_IOAT, "%s channel=%u dispatch2 hw_head=%u head=%u", __func__,
982 	    ioat->chan_idx, ioat->hw_head & UINT16_MAX, ioat->head);
983 
984 	if (ioat->acq_head != ioat->head) {
985 		ioat_write_2(ioat, IOAT_DMACOUNT_OFFSET,
986 		    (uint16_t)ioat->hw_head);
987 
988 		if (!ioat->is_completion_pending) {
989 			ioat->is_completion_pending = TRUE;
990 			callout_reset(&ioat->poll_timer, 1,
991 			    ioat_poll_timer_callback, ioat);
992 		}
993 	}
994 	mtx_unlock(&ioat->submit_lock);
995 }
996 
997 static struct ioat_descriptor *
998 ioat_op_generic(struct ioat_softc *ioat, uint8_t op,
999     uint32_t size, uint64_t src, uint64_t dst,
1000     bus_dmaengine_callback_t callback_fn, void *callback_arg,
1001     uint32_t flags)
1002 {
1003 	struct ioat_generic_hw_descriptor *hw_desc;
1004 	struct ioat_descriptor *desc;
1005 	int mflags;
1006 
1007 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1008 
1009 	KASSERT((flags & ~_DMA_GENERIC_FLAGS) == 0,
1010 	    ("Unrecognized flag(s): %#x", flags & ~_DMA_GENERIC_FLAGS));
1011 	if ((flags & DMA_NO_WAIT) != 0)
1012 		mflags = M_NOWAIT;
1013 	else
1014 		mflags = M_WAITOK;
1015 
1016 	if (size > ioat->max_xfer_size) {
1017 		ioat_log_message(0, "%s: max_xfer_size = %d, requested = %u\n",
1018 		    __func__, ioat->max_xfer_size, (unsigned)size);
1019 		return (NULL);
1020 	}
1021 
1022 	if (ioat_reserve_space(ioat, 1, mflags) != 0)
1023 		return (NULL);
1024 
1025 	desc = ioat_get_ring_entry(ioat, ioat->head);
1026 	hw_desc = &ioat_get_descriptor(ioat, ioat->head)->generic;
1027 
1028 	hw_desc->u.control_raw = 0;
1029 	hw_desc->u.control_generic.op = op;
1030 	hw_desc->u.control_generic.completion_update = 1;
1031 
1032 	if ((flags & DMA_INT_EN) != 0)
1033 		hw_desc->u.control_generic.int_enable = 1;
1034 	if ((flags & DMA_FENCE) != 0)
1035 		hw_desc->u.control_generic.fence = 1;
1036 
1037 	hw_desc->size = size;
1038 	hw_desc->src_addr = src;
1039 	hw_desc->dest_addr = dst;
1040 
1041 	desc->bus_dmadesc.callback_fn = callback_fn;
1042 	desc->bus_dmadesc.callback_arg = callback_arg;
1043 	return (desc);
1044 }
1045 
1046 struct bus_dmadesc *
1047 ioat_null(bus_dmaengine_t dmaengine, bus_dmaengine_callback_t callback_fn,
1048     void *callback_arg, uint32_t flags)
1049 {
1050 	struct ioat_dma_hw_descriptor *hw_desc;
1051 	struct ioat_descriptor *desc;
1052 	struct ioat_softc *ioat;
1053 
1054 	ioat = to_ioat_softc(dmaengine);
1055 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1056 
1057 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, 8, 0, 0, callback_fn,
1058 	    callback_arg, flags);
1059 	if (desc == NULL)
1060 		return (NULL);
1061 
1062 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->dma;
1063 	hw_desc->u.control.null = 1;
1064 	ioat_submit_single(ioat);
1065 	return (&desc->bus_dmadesc);
1066 }
1067 
1068 struct bus_dmadesc *
1069 ioat_copy(bus_dmaengine_t dmaengine, bus_addr_t dst,
1070     bus_addr_t src, bus_size_t len, bus_dmaengine_callback_t callback_fn,
1071     void *callback_arg, uint32_t flags)
1072 {
1073 	struct ioat_dma_hw_descriptor *hw_desc;
1074 	struct ioat_descriptor *desc;
1075 	struct ioat_softc *ioat;
1076 
1077 	ioat = to_ioat_softc(dmaengine);
1078 
1079 	if (((src | dst) & (0xffffull << 48)) != 0) {
1080 		ioat_log_message(0, "%s: High 16 bits of src/dst invalid\n",
1081 		    __func__);
1082 		return (NULL);
1083 	}
1084 
1085 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, len, src, dst, callback_fn,
1086 	    callback_arg, flags);
1087 	if (desc == NULL)
1088 		return (NULL);
1089 
1090 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->dma;
1091 	if (g_ioat_debug_level >= 3)
1092 		dump_descriptor(hw_desc);
1093 
1094 	ioat_submit_single(ioat);
1095 	CTR6(KTR_IOAT, "%s channel=%u desc=%p dest=%lx src=%lx len=%lx",
1096 	    __func__, ioat->chan_idx, &desc->bus_dmadesc, dst, src, len);
1097 	return (&desc->bus_dmadesc);
1098 }
1099 
1100 struct bus_dmadesc *
1101 ioat_copy_8k_aligned(bus_dmaengine_t dmaengine, bus_addr_t dst1,
1102     bus_addr_t dst2, bus_addr_t src1, bus_addr_t src2,
1103     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags)
1104 {
1105 	struct ioat_dma_hw_descriptor *hw_desc;
1106 	struct ioat_descriptor *desc;
1107 	struct ioat_softc *ioat;
1108 
1109 	ioat = to_ioat_softc(dmaengine);
1110 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1111 
1112 	if (((src1 | src2 | dst1 | dst2) & (0xffffull << 48)) != 0) {
1113 		ioat_log_message(0, "%s: High 16 bits of src/dst invalid\n",
1114 		    __func__);
1115 		return (NULL);
1116 	}
1117 	if (((src1 | src2 | dst1 | dst2) & PAGE_MASK) != 0) {
1118 		ioat_log_message(0, "%s: Addresses must be page-aligned\n",
1119 		    __func__);
1120 		return (NULL);
1121 	}
1122 
1123 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, 2 * PAGE_SIZE, src1, dst1,
1124 	    callback_fn, callback_arg, flags);
1125 	if (desc == NULL)
1126 		return (NULL);
1127 
1128 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->dma;
1129 	if (src2 != src1 + PAGE_SIZE) {
1130 		hw_desc->u.control.src_page_break = 1;
1131 		hw_desc->next_src_addr = src2;
1132 	}
1133 	if (dst2 != dst1 + PAGE_SIZE) {
1134 		hw_desc->u.control.dest_page_break = 1;
1135 		hw_desc->next_dest_addr = dst2;
1136 	}
1137 
1138 	if (g_ioat_debug_level >= 3)
1139 		dump_descriptor(hw_desc);
1140 
1141 	ioat_submit_single(ioat);
1142 	return (&desc->bus_dmadesc);
1143 }
1144 
1145 struct bus_dmadesc *
1146 ioat_copy_crc(bus_dmaengine_t dmaengine, bus_addr_t dst, bus_addr_t src,
1147     bus_size_t len, uint32_t *initialseed, bus_addr_t crcptr,
1148     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags)
1149 {
1150 	struct ioat_crc32_hw_descriptor *hw_desc;
1151 	struct ioat_descriptor *desc;
1152 	struct ioat_softc *ioat;
1153 	uint32_t teststore;
1154 	uint8_t op;
1155 
1156 	ioat = to_ioat_softc(dmaengine);
1157 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1158 
1159 	if ((ioat->capabilities & IOAT_DMACAP_MOVECRC) == 0) {
1160 		ioat_log_message(0, "%s: Device lacks MOVECRC capability\n",
1161 		    __func__);
1162 		return (NULL);
1163 	}
1164 	if (((src | dst) & (0xffffffull << 40)) != 0) {
1165 		ioat_log_message(0, "%s: High 24 bits of src/dst invalid\n",
1166 		    __func__);
1167 		return (NULL);
1168 	}
1169 	teststore = (flags & _DMA_CRC_TESTSTORE);
1170 	if (teststore == _DMA_CRC_TESTSTORE) {
1171 		ioat_log_message(0, "%s: TEST and STORE invalid\n", __func__);
1172 		return (NULL);
1173 	}
1174 	if (teststore == 0 && (flags & DMA_CRC_INLINE) != 0) {
1175 		ioat_log_message(0, "%s: INLINE invalid without TEST or STORE\n",
1176 		    __func__);
1177 		return (NULL);
1178 	}
1179 
1180 	switch (teststore) {
1181 	case DMA_CRC_STORE:
1182 		op = IOAT_OP_MOVECRC_STORE;
1183 		break;
1184 	case DMA_CRC_TEST:
1185 		op = IOAT_OP_MOVECRC_TEST;
1186 		break;
1187 	default:
1188 		KASSERT(teststore == 0, ("bogus"));
1189 		op = IOAT_OP_MOVECRC;
1190 		break;
1191 	}
1192 
1193 	if ((flags & DMA_CRC_INLINE) == 0 &&
1194 	    (crcptr & (0xffffffull << 40)) != 0) {
1195 		ioat_log_message(0,
1196 		    "%s: High 24 bits of crcptr invalid\n", __func__);
1197 		return (NULL);
1198 	}
1199 
1200 	desc = ioat_op_generic(ioat, op, len, src, dst, callback_fn,
1201 	    callback_arg, flags & ~_DMA_CRC_FLAGS);
1202 	if (desc == NULL)
1203 		return (NULL);
1204 
1205 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->crc32;
1206 
1207 	if ((flags & DMA_CRC_INLINE) == 0)
1208 		hw_desc->crc_address = crcptr;
1209 	else
1210 		hw_desc->u.control.crc_location = 1;
1211 
1212 	if (initialseed != NULL) {
1213 		hw_desc->u.control.use_seed = 1;
1214 		hw_desc->seed = *initialseed;
1215 	}
1216 
1217 	if (g_ioat_debug_level >= 3)
1218 		dump_descriptor(hw_desc);
1219 
1220 	ioat_submit_single(ioat);
1221 	return (&desc->bus_dmadesc);
1222 }
1223 
1224 struct bus_dmadesc *
1225 ioat_crc(bus_dmaengine_t dmaengine, bus_addr_t src, bus_size_t len,
1226     uint32_t *initialseed, bus_addr_t crcptr,
1227     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags)
1228 {
1229 	struct ioat_crc32_hw_descriptor *hw_desc;
1230 	struct ioat_descriptor *desc;
1231 	struct ioat_softc *ioat;
1232 	uint32_t teststore;
1233 	uint8_t op;
1234 
1235 	ioat = to_ioat_softc(dmaengine);
1236 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1237 
1238 	if ((ioat->capabilities & IOAT_DMACAP_CRC) == 0) {
1239 		ioat_log_message(0, "%s: Device lacks CRC capability\n",
1240 		    __func__);
1241 		return (NULL);
1242 	}
1243 	if ((src & (0xffffffull << 40)) != 0) {
1244 		ioat_log_message(0, "%s: High 24 bits of src invalid\n",
1245 		    __func__);
1246 		return (NULL);
1247 	}
1248 	teststore = (flags & _DMA_CRC_TESTSTORE);
1249 	if (teststore == _DMA_CRC_TESTSTORE) {
1250 		ioat_log_message(0, "%s: TEST and STORE invalid\n", __func__);
1251 		return (NULL);
1252 	}
1253 	if (teststore == 0 && (flags & DMA_CRC_INLINE) != 0) {
1254 		ioat_log_message(0, "%s: INLINE invalid without TEST or STORE\n",
1255 		    __func__);
1256 		return (NULL);
1257 	}
1258 
1259 	switch (teststore) {
1260 	case DMA_CRC_STORE:
1261 		op = IOAT_OP_CRC_STORE;
1262 		break;
1263 	case DMA_CRC_TEST:
1264 		op = IOAT_OP_CRC_TEST;
1265 		break;
1266 	default:
1267 		KASSERT(teststore == 0, ("bogus"));
1268 		op = IOAT_OP_CRC;
1269 		break;
1270 	}
1271 
1272 	if ((flags & DMA_CRC_INLINE) == 0 &&
1273 	    (crcptr & (0xffffffull << 40)) != 0) {
1274 		ioat_log_message(0,
1275 		    "%s: High 24 bits of crcptr invalid\n", __func__);
1276 		return (NULL);
1277 	}
1278 
1279 	desc = ioat_op_generic(ioat, op, len, src, 0, callback_fn,
1280 	    callback_arg, flags & ~_DMA_CRC_FLAGS);
1281 	if (desc == NULL)
1282 		return (NULL);
1283 
1284 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->crc32;
1285 
1286 	if ((flags & DMA_CRC_INLINE) == 0)
1287 		hw_desc->crc_address = crcptr;
1288 	else
1289 		hw_desc->u.control.crc_location = 1;
1290 
1291 	if (initialseed != NULL) {
1292 		hw_desc->u.control.use_seed = 1;
1293 		hw_desc->seed = *initialseed;
1294 	}
1295 
1296 	if (g_ioat_debug_level >= 3)
1297 		dump_descriptor(hw_desc);
1298 
1299 	ioat_submit_single(ioat);
1300 	return (&desc->bus_dmadesc);
1301 }
1302 
1303 struct bus_dmadesc *
1304 ioat_blockfill(bus_dmaengine_t dmaengine, bus_addr_t dst, uint64_t fillpattern,
1305     bus_size_t len, bus_dmaengine_callback_t callback_fn, void *callback_arg,
1306     uint32_t flags)
1307 {
1308 	struct ioat_fill_hw_descriptor *hw_desc;
1309 	struct ioat_descriptor *desc;
1310 	struct ioat_softc *ioat;
1311 
1312 	ioat = to_ioat_softc(dmaengine);
1313 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1314 
1315 	if ((ioat->capabilities & IOAT_DMACAP_BFILL) == 0) {
1316 		ioat_log_message(0, "%s: Device lacks BFILL capability\n",
1317 		    __func__);
1318 		return (NULL);
1319 	}
1320 
1321 	if ((dst & (0xffffull << 48)) != 0) {
1322 		ioat_log_message(0, "%s: High 16 bits of dst invalid\n",
1323 		    __func__);
1324 		return (NULL);
1325 	}
1326 
1327 	desc = ioat_op_generic(ioat, IOAT_OP_FILL, len, fillpattern, dst,
1328 	    callback_fn, callback_arg, flags);
1329 	if (desc == NULL)
1330 		return (NULL);
1331 
1332 	hw_desc = &ioat_get_descriptor(ioat, desc->id)->fill;
1333 	if (g_ioat_debug_level >= 3)
1334 		dump_descriptor(hw_desc);
1335 
1336 	ioat_submit_single(ioat);
1337 	return (&desc->bus_dmadesc);
1338 }
1339 
1340 /*
1341  * Ring Management
1342  */
1343 static inline uint32_t
1344 ioat_get_active(struct ioat_softc *ioat)
1345 {
1346 
1347 	return ((ioat->head - ioat->tail) & ((1 << ioat->ring_size_order) - 1));
1348 }
1349 
1350 static inline uint32_t
1351 ioat_get_ring_space(struct ioat_softc *ioat)
1352 {
1353 
1354 	return ((1 << ioat->ring_size_order) - ioat_get_active(ioat) - 1);
1355 }
1356 
1357 /*
1358  * Reserves space in this IOAT descriptor ring by ensuring enough slots remain
1359  * for 'num_descs'.
1360  *
1361  * If mflags contains M_WAITOK, blocks until enough space is available.
1362  *
1363  * Returns zero on success, or an errno on error.  If num_descs is beyond the
1364  * maximum ring size, returns EINVAl; if allocation would block and mflags
1365  * contains M_NOWAIT, returns EAGAIN.
1366  *
1367  * Must be called with the submit_lock held; returns with the lock held.  The
1368  * lock may be dropped to allocate the ring.
1369  *
1370  * (The submit_lock is needed to add any entries to the ring, so callers are
1371  * assured enough room is available.)
1372  */
1373 static int
1374 ioat_reserve_space(struct ioat_softc *ioat, uint32_t num_descs, int mflags)
1375 {
1376 	boolean_t dug;
1377 	int error;
1378 
1379 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1380 	error = 0;
1381 	dug = FALSE;
1382 
1383 	if (num_descs < 1 || num_descs >= (1 << ioat->ring_size_order)) {
1384 		error = EINVAL;
1385 		goto out;
1386 	}
1387 
1388 	for (;;) {
1389 		if (ioat->quiescing) {
1390 			error = ENXIO;
1391 			goto out;
1392 		}
1393 
1394 		if (ioat_get_ring_space(ioat) >= num_descs)
1395 			goto out;
1396 
1397 		CTR3(KTR_IOAT, "%s channel=%u starved (%u)", __func__,
1398 		    ioat->chan_idx, num_descs);
1399 
1400 		if (!dug && !ioat->is_submitter_processing) {
1401 			ioat->is_submitter_processing = TRUE;
1402 			mtx_unlock(&ioat->submit_lock);
1403 
1404 			CTR2(KTR_IOAT, "%s channel=%u attempting to process events",
1405 			    __func__, ioat->chan_idx);
1406 			ioat_process_events(ioat);
1407 
1408 			mtx_lock(&ioat->submit_lock);
1409 			dug = TRUE;
1410 			KASSERT(ioat->is_submitter_processing == TRUE,
1411 			    ("is_submitter_processing"));
1412 			ioat->is_submitter_processing = FALSE;
1413 			wakeup(&ioat->tail);
1414 			continue;
1415 		}
1416 
1417 		if ((mflags & M_WAITOK) == 0) {
1418 			error = EAGAIN;
1419 			break;
1420 		}
1421 		CTR2(KTR_IOAT, "%s channel=%u blocking on completions",
1422 		    __func__, ioat->chan_idx);
1423 		msleep(&ioat->tail, &ioat->submit_lock, 0,
1424 		    "ioat_full", 0);
1425 		continue;
1426 	}
1427 
1428 out:
1429 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1430 	KASSERT(!ioat->quiescing || error == ENXIO,
1431 	    ("reserved during quiesce"));
1432 	return (error);
1433 }
1434 
1435 static void
1436 ioat_free_ring(struct ioat_softc *ioat, uint32_t size,
1437     struct ioat_descriptor *ring)
1438 {
1439 
1440 	free(ring, M_IOAT);
1441 }
1442 
1443 static struct ioat_descriptor *
1444 ioat_get_ring_entry(struct ioat_softc *ioat, uint32_t index)
1445 {
1446 
1447 	return (&ioat->ring[index % (1 << ioat->ring_size_order)]);
1448 }
1449 
1450 static union ioat_hw_descriptor *
1451 ioat_get_descriptor(struct ioat_softc *ioat, uint32_t index)
1452 {
1453 
1454 	return (&ioat->hw_desc_ring[index % (1 << ioat->ring_size_order)]);
1455 }
1456 
1457 static void
1458 ioat_halted_debug(struct ioat_softc *ioat, uint32_t chanerr)
1459 {
1460 	union ioat_hw_descriptor *desc;
1461 
1462 	ioat_log_message(0, "Channel halted (%b)\n", (int)chanerr,
1463 	    IOAT_CHANERR_STR);
1464 	if (chanerr == 0)
1465 		return;
1466 
1467 	mtx_assert(&ioat->cleanup_lock, MA_OWNED);
1468 
1469 	desc = ioat_get_descriptor(ioat, ioat->tail + 0);
1470 	dump_descriptor(desc);
1471 
1472 	desc = ioat_get_descriptor(ioat, ioat->tail + 1);
1473 	dump_descriptor(desc);
1474 }
1475 
1476 static void
1477 ioat_poll_timer_callback(void *arg)
1478 {
1479 	struct ioat_softc *ioat;
1480 
1481 	ioat = arg;
1482 	ioat_log_message(3, "%s\n", __func__);
1483 
1484 	ioat_process_events(ioat);
1485 }
1486 
1487 /*
1488  * Support Functions
1489  */
1490 static void
1491 ioat_submit_single(struct ioat_softc *ioat)
1492 {
1493 
1494 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1495 
1496 	ioat_get(ioat, IOAT_ACTIVE_DESCR_REF);
1497 	atomic_add_rel_int(&ioat->head, 1);
1498 	atomic_add_rel_int(&ioat->hw_head, 1);
1499 	CTR5(KTR_IOAT, "%s channel=%u head=%u hw_head=%u tail=%u", __func__,
1500 	    ioat->chan_idx, ioat->head, ioat->hw_head & UINT16_MAX,
1501 	    ioat->tail);
1502 
1503 	ioat->stats.descriptors_submitted++;
1504 }
1505 
1506 static int
1507 ioat_reset_hw(struct ioat_softc *ioat)
1508 {
1509 	uint64_t status;
1510 	uint32_t chanerr;
1511 	unsigned timeout;
1512 	int error;
1513 
1514 	CTR2(KTR_IOAT, "%s channel=%u", __func__, ioat->chan_idx);
1515 
1516 	mtx_lock(IOAT_REFLK);
1517 	while (ioat->resetting && !ioat->destroying)
1518 		msleep(&ioat->resetting, IOAT_REFLK, 0, "IRH_drain", 0);
1519 	if (ioat->destroying) {
1520 		mtx_unlock(IOAT_REFLK);
1521 		return (ENXIO);
1522 	}
1523 	ioat->resetting = TRUE;
1524 
1525 	ioat->quiescing = TRUE;
1526 	ioat_drain_locked(ioat);
1527 	mtx_unlock(IOAT_REFLK);
1528 
1529 	/*
1530 	 * Suspend ioat_process_events while the hardware and softc are in an
1531 	 * indeterminate state.
1532 	 */
1533 	mtx_lock(&ioat->cleanup_lock);
1534 	ioat->resetting_cleanup = TRUE;
1535 	mtx_unlock(&ioat->cleanup_lock);
1536 
1537 	CTR2(KTR_IOAT, "%s channel=%u quiesced and drained", __func__,
1538 	    ioat->chan_idx);
1539 
1540 	status = ioat_get_chansts(ioat);
1541 	if (is_ioat_active(status) || is_ioat_idle(status))
1542 		ioat_suspend(ioat);
1543 
1544 	/* Wait at most 20 ms */
1545 	for (timeout = 0; (is_ioat_active(status) || is_ioat_idle(status)) &&
1546 	    timeout < 20; timeout++) {
1547 		DELAY(1000);
1548 		status = ioat_get_chansts(ioat);
1549 	}
1550 	if (timeout == 20) {
1551 		error = ETIMEDOUT;
1552 		goto out;
1553 	}
1554 
1555 	KASSERT(ioat_get_active(ioat) == 0, ("active after quiesce"));
1556 
1557 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
1558 	ioat_write_4(ioat, IOAT_CHANERR_OFFSET, chanerr);
1559 
1560 	CTR2(KTR_IOAT, "%s channel=%u hardware suspended", __func__,
1561 	    ioat->chan_idx);
1562 
1563 	/*
1564 	 * IOAT v3 workaround - CHANERRMSK_INT with 3E07h to masks out errors
1565 	 *  that can cause stability issues for IOAT v3.
1566 	 */
1567 	pci_write_config(ioat->device, IOAT_CFG_CHANERRMASK_INT_OFFSET, 0x3e07,
1568 	    4);
1569 	chanerr = pci_read_config(ioat->device, IOAT_CFG_CHANERR_INT_OFFSET, 4);
1570 	pci_write_config(ioat->device, IOAT_CFG_CHANERR_INT_OFFSET, chanerr, 4);
1571 
1572 	/*
1573 	 * BDXDE and BWD models reset MSI-X registers on device reset.
1574 	 * Save/restore their contents manually.
1575 	 */
1576 	if (ioat_model_resets_msix(ioat)) {
1577 		ioat_log_message(1, "device resets MSI-X registers; saving\n");
1578 		pci_save_state(ioat->device);
1579 	}
1580 
1581 	ioat_reset(ioat);
1582 	CTR2(KTR_IOAT, "%s channel=%u hardware reset", __func__,
1583 	    ioat->chan_idx);
1584 
1585 	/* Wait at most 20 ms */
1586 	for (timeout = 0; ioat_reset_pending(ioat) && timeout < 20; timeout++)
1587 		DELAY(1000);
1588 	if (timeout == 20) {
1589 		error = ETIMEDOUT;
1590 		goto out;
1591 	}
1592 
1593 	if (ioat_model_resets_msix(ioat)) {
1594 		ioat_log_message(1, "device resets registers; restored\n");
1595 		pci_restore_state(ioat->device);
1596 	}
1597 
1598 	/* Reset attempts to return the hardware to "halted." */
1599 	status = ioat_get_chansts(ioat);
1600 	if (is_ioat_active(status) || is_ioat_idle(status)) {
1601 		/* So this really shouldn't happen... */
1602 		ioat_log_message(0, "Device is active after a reset?\n");
1603 		ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
1604 		error = 0;
1605 		goto out;
1606 	}
1607 
1608 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
1609 	if (chanerr != 0) {
1610 		mtx_lock(&ioat->cleanup_lock);
1611 		ioat_halted_debug(ioat, chanerr);
1612 		mtx_unlock(&ioat->cleanup_lock);
1613 		error = EIO;
1614 		goto out;
1615 	}
1616 
1617 	/*
1618 	 * Bring device back online after reset.  Writing CHAINADDR brings the
1619 	 * device back to active.
1620 	 *
1621 	 * The internal ring counter resets to zero, so we have to start over
1622 	 * at zero as well.
1623 	 */
1624 	ioat->tail = ioat->head = ioat->hw_head = 0;
1625 	ioat->last_seen = 0;
1626 	*ioat->comp_update = 0;
1627 	KASSERT(!ioat->is_completion_pending, ("bogus completion_pending"));
1628 
1629 	ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
1630 	ioat_write_chancmp(ioat, ioat->comp_update_bus_addr);
1631 	ioat_write_chainaddr(ioat, RING_PHYS_ADDR(ioat, 0));
1632 	error = 0;
1633 	CTR2(KTR_IOAT, "%s channel=%u configured channel", __func__,
1634 	    ioat->chan_idx);
1635 
1636 out:
1637 	/* Enqueues a null operation and ensures it completes. */
1638 	if (error == 0) {
1639 		error = ioat_start_channel(ioat);
1640 		CTR2(KTR_IOAT, "%s channel=%u started channel", __func__,
1641 		    ioat->chan_idx);
1642 	}
1643 
1644 	/*
1645 	 * Resume completions now that ring state is consistent.
1646 	 */
1647 	mtx_lock(&ioat->cleanup_lock);
1648 	ioat->resetting_cleanup = FALSE;
1649 	mtx_unlock(&ioat->cleanup_lock);
1650 
1651 	/* Unblock submission of new work */
1652 	mtx_lock(IOAT_REFLK);
1653 	ioat->quiescing = FALSE;
1654 	wakeup(&ioat->quiescing);
1655 
1656 	ioat->resetting = FALSE;
1657 	wakeup(&ioat->resetting);
1658 
1659 	if (ioat->is_completion_pending)
1660 		callout_reset(&ioat->poll_timer, 1, ioat_poll_timer_callback,
1661 		    ioat);
1662 	CTR2(KTR_IOAT, "%s channel=%u reset done", __func__, ioat->chan_idx);
1663 	mtx_unlock(IOAT_REFLK);
1664 
1665 	return (error);
1666 }
1667 
1668 static int
1669 sysctl_handle_chansts(SYSCTL_HANDLER_ARGS)
1670 {
1671 	struct ioat_softc *ioat;
1672 	struct sbuf sb;
1673 	uint64_t status;
1674 	int error;
1675 
1676 	ioat = arg1;
1677 
1678 	status = ioat_get_chansts(ioat) & IOAT_CHANSTS_STATUS;
1679 
1680 	sbuf_new_for_sysctl(&sb, NULL, 256, req);
1681 	switch (status) {
1682 	case IOAT_CHANSTS_ACTIVE:
1683 		sbuf_printf(&sb, "ACTIVE");
1684 		break;
1685 	case IOAT_CHANSTS_IDLE:
1686 		sbuf_printf(&sb, "IDLE");
1687 		break;
1688 	case IOAT_CHANSTS_SUSPENDED:
1689 		sbuf_printf(&sb, "SUSPENDED");
1690 		break;
1691 	case IOAT_CHANSTS_HALTED:
1692 		sbuf_printf(&sb, "HALTED");
1693 		break;
1694 	case IOAT_CHANSTS_ARMED:
1695 		sbuf_printf(&sb, "ARMED");
1696 		break;
1697 	default:
1698 		sbuf_printf(&sb, "UNKNOWN");
1699 		break;
1700 	}
1701 	error = sbuf_finish(&sb);
1702 	sbuf_delete(&sb);
1703 
1704 	if (error != 0 || req->newptr == NULL)
1705 		return (error);
1706 	return (EINVAL);
1707 }
1708 
1709 static int
1710 sysctl_handle_dpi(SYSCTL_HANDLER_ARGS)
1711 {
1712 	struct ioat_softc *ioat;
1713 	struct sbuf sb;
1714 #define	PRECISION	"1"
1715 	const uintmax_t factor = 10;
1716 	uintmax_t rate;
1717 	int error;
1718 
1719 	ioat = arg1;
1720 	sbuf_new_for_sysctl(&sb, NULL, 16, req);
1721 
1722 	if (ioat->stats.interrupts == 0) {
1723 		sbuf_printf(&sb, "NaN");
1724 		goto out;
1725 	}
1726 	rate = ioat->stats.descriptors_processed * factor /
1727 	    ioat->stats.interrupts;
1728 	sbuf_printf(&sb, "%ju.%." PRECISION "ju", rate / factor,
1729 	    rate % factor);
1730 #undef	PRECISION
1731 out:
1732 	error = sbuf_finish(&sb);
1733 	sbuf_delete(&sb);
1734 	if (error != 0 || req->newptr == NULL)
1735 		return (error);
1736 	return (EINVAL);
1737 }
1738 
1739 static int
1740 sysctl_handle_reset(SYSCTL_HANDLER_ARGS)
1741 {
1742 	struct ioat_softc *ioat;
1743 	int error, arg;
1744 
1745 	ioat = arg1;
1746 
1747 	arg = 0;
1748 	error = SYSCTL_OUT(req, &arg, sizeof(arg));
1749 	if (error != 0 || req->newptr == NULL)
1750 		return (error);
1751 
1752 	error = SYSCTL_IN(req, &arg, sizeof(arg));
1753 	if (error != 0)
1754 		return (error);
1755 
1756 	if (arg != 0)
1757 		error = ioat_reset_hw(ioat);
1758 
1759 	return (error);
1760 }
1761 
1762 static void
1763 dump_descriptor(void *hw_desc)
1764 {
1765 	int i, j;
1766 
1767 	for (i = 0; i < 2; i++) {
1768 		for (j = 0; j < 8; j++)
1769 			printf("%08x ", ((uint32_t *)hw_desc)[i * 8 + j]);
1770 		printf("\n");
1771 	}
1772 }
1773 
1774 static void
1775 ioat_setup_sysctl(device_t device)
1776 {
1777 	struct sysctl_oid_list *par, *statpar, *state, *hammer;
1778 	struct sysctl_ctx_list *ctx;
1779 	struct sysctl_oid *tree, *tmp;
1780 	struct ioat_softc *ioat;
1781 
1782 	ioat = DEVICE2SOFTC(device);
1783 	ctx = device_get_sysctl_ctx(device);
1784 	tree = device_get_sysctl_tree(device);
1785 	par = SYSCTL_CHILDREN(tree);
1786 
1787 	SYSCTL_ADD_INT(ctx, par, OID_AUTO, "version", CTLFLAG_RD,
1788 	    &ioat->version, 0, "HW version (0xMM form)");
1789 	SYSCTL_ADD_UINT(ctx, par, OID_AUTO, "max_xfer_size", CTLFLAG_RD,
1790 	    &ioat->max_xfer_size, 0, "HW maximum transfer size");
1791 	SYSCTL_ADD_INT(ctx, par, OID_AUTO, "intrdelay_supported", CTLFLAG_RD,
1792 	    &ioat->intrdelay_supported, 0, "Is INTRDELAY supported");
1793 	SYSCTL_ADD_U16(ctx, par, OID_AUTO, "intrdelay_max", CTLFLAG_RD,
1794 	    &ioat->intrdelay_max, 0,
1795 	    "Maximum configurable INTRDELAY on this channel (microseconds)");
1796 
1797 	tmp = SYSCTL_ADD_NODE(ctx, par, OID_AUTO, "state", CTLFLAG_RD, NULL,
1798 	    "IOAT channel internal state");
1799 	state = SYSCTL_CHILDREN(tmp);
1800 
1801 	SYSCTL_ADD_UINT(ctx, state, OID_AUTO, "ring_size_order", CTLFLAG_RD,
1802 	    &ioat->ring_size_order, 0, "SW descriptor ring size order");
1803 	SYSCTL_ADD_UINT(ctx, state, OID_AUTO, "head", CTLFLAG_RD, &ioat->head,
1804 	    0, "SW descriptor head pointer index");
1805 	SYSCTL_ADD_UINT(ctx, state, OID_AUTO, "tail", CTLFLAG_RD, &ioat->tail,
1806 	    0, "SW descriptor tail pointer index");
1807 	SYSCTL_ADD_UINT(ctx, state, OID_AUTO, "hw_head", CTLFLAG_RD,
1808 	    &ioat->hw_head, 0, "HW DMACOUNT");
1809 
1810 	SYSCTL_ADD_UQUAD(ctx, state, OID_AUTO, "last_completion", CTLFLAG_RD,
1811 	    ioat->comp_update, "HW addr of last completion");
1812 
1813 	SYSCTL_ADD_INT(ctx, state, OID_AUTO, "is_submitter_processing",
1814 	    CTLFLAG_RD, &ioat->is_submitter_processing, 0,
1815 	    "submitter processing");
1816 	SYSCTL_ADD_INT(ctx, state, OID_AUTO, "is_completion_pending",
1817 	    CTLFLAG_RD, &ioat->is_completion_pending, 0, "completion pending");
1818 	SYSCTL_ADD_INT(ctx, state, OID_AUTO, "is_reset_pending", CTLFLAG_RD,
1819 	    &ioat->is_reset_pending, 0, "reset pending");
1820 	SYSCTL_ADD_INT(ctx, state, OID_AUTO, "is_channel_running", CTLFLAG_RD,
1821 	    &ioat->is_channel_running, 0, "channel running");
1822 
1823 	SYSCTL_ADD_PROC(ctx, state, OID_AUTO, "chansts",
1824 	    CTLTYPE_STRING | CTLFLAG_RD, ioat, 0, sysctl_handle_chansts, "A",
1825 	    "String of the channel status");
1826 
1827 	SYSCTL_ADD_U16(ctx, state, OID_AUTO, "intrdelay", CTLFLAG_RD,
1828 	    &ioat->cached_intrdelay, 0,
1829 	    "Current INTRDELAY on this channel (cached, microseconds)");
1830 
1831 	tmp = SYSCTL_ADD_NODE(ctx, par, OID_AUTO, "hammer", CTLFLAG_RD, NULL,
1832 	    "Big hammers (mostly for testing)");
1833 	hammer = SYSCTL_CHILDREN(tmp);
1834 
1835 	SYSCTL_ADD_PROC(ctx, hammer, OID_AUTO, "force_hw_reset",
1836 	    CTLTYPE_INT | CTLFLAG_RW, ioat, 0, sysctl_handle_reset, "I",
1837 	    "Set to non-zero to reset the hardware");
1838 
1839 	tmp = SYSCTL_ADD_NODE(ctx, par, OID_AUTO, "stats", CTLFLAG_RD, NULL,
1840 	    "IOAT channel statistics");
1841 	statpar = SYSCTL_CHILDREN(tmp);
1842 
1843 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "interrupts", CTLFLAG_RW,
1844 	    &ioat->stats.interrupts,
1845 	    "Number of interrupts processed on this channel");
1846 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "descriptors", CTLFLAG_RW,
1847 	    &ioat->stats.descriptors_processed,
1848 	    "Number of descriptors processed on this channel");
1849 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "submitted", CTLFLAG_RW,
1850 	    &ioat->stats.descriptors_submitted,
1851 	    "Number of descriptors submitted to this channel");
1852 	SYSCTL_ADD_UQUAD(ctx, statpar, OID_AUTO, "errored", CTLFLAG_RW,
1853 	    &ioat->stats.descriptors_error,
1854 	    "Number of descriptors failed by channel errors");
1855 	SYSCTL_ADD_U32(ctx, statpar, OID_AUTO, "halts", CTLFLAG_RW,
1856 	    &ioat->stats.channel_halts, 0,
1857 	    "Number of times the channel has halted");
1858 	SYSCTL_ADD_U32(ctx, statpar, OID_AUTO, "last_halt_chanerr", CTLFLAG_RW,
1859 	    &ioat->stats.last_halt_chanerr, 0,
1860 	    "The raw CHANERR when the channel was last halted");
1861 
1862 	SYSCTL_ADD_PROC(ctx, statpar, OID_AUTO, "desc_per_interrupt",
1863 	    CTLTYPE_STRING | CTLFLAG_RD, ioat, 0, sysctl_handle_dpi, "A",
1864 	    "Descriptors per interrupt");
1865 }
1866 
1867 static inline struct ioat_softc *
1868 ioat_get(struct ioat_softc *ioat, enum ioat_ref_kind kind)
1869 {
1870 	uint32_t old;
1871 
1872 	KASSERT(kind < IOAT_NUM_REF_KINDS, ("bogus"));
1873 
1874 	old = atomic_fetchadd_32(&ioat->refcnt, 1);
1875 	KASSERT(old < UINT32_MAX, ("refcnt overflow"));
1876 
1877 #ifdef INVARIANTS
1878 	old = atomic_fetchadd_32(&ioat->refkinds[kind], 1);
1879 	KASSERT(old < UINT32_MAX, ("refcnt kind overflow"));
1880 #endif
1881 
1882 	return (ioat);
1883 }
1884 
1885 static inline void
1886 ioat_putn(struct ioat_softc *ioat, uint32_t n, enum ioat_ref_kind kind)
1887 {
1888 
1889 	_ioat_putn(ioat, n, kind, FALSE);
1890 }
1891 
1892 static inline void
1893 ioat_putn_locked(struct ioat_softc *ioat, uint32_t n, enum ioat_ref_kind kind)
1894 {
1895 
1896 	_ioat_putn(ioat, n, kind, TRUE);
1897 }
1898 
1899 static inline void
1900 _ioat_putn(struct ioat_softc *ioat, uint32_t n, enum ioat_ref_kind kind,
1901     boolean_t locked)
1902 {
1903 	uint32_t old;
1904 
1905 	KASSERT(kind < IOAT_NUM_REF_KINDS, ("bogus"));
1906 
1907 	if (n == 0)
1908 		return;
1909 
1910 #ifdef INVARIANTS
1911 	old = atomic_fetchadd_32(&ioat->refkinds[kind], -n);
1912 	KASSERT(old >= n, ("refcnt kind underflow"));
1913 #endif
1914 
1915 	/* Skip acquiring the lock if resulting refcnt > 0. */
1916 	for (;;) {
1917 		old = ioat->refcnt;
1918 		if (old <= n)
1919 			break;
1920 		if (atomic_cmpset_32(&ioat->refcnt, old, old - n))
1921 			return;
1922 	}
1923 
1924 	if (locked)
1925 		mtx_assert(IOAT_REFLK, MA_OWNED);
1926 	else
1927 		mtx_lock(IOAT_REFLK);
1928 
1929 	old = atomic_fetchadd_32(&ioat->refcnt, -n);
1930 	KASSERT(old >= n, ("refcnt error"));
1931 
1932 	if (old == n)
1933 		wakeup(IOAT_REFLK);
1934 	if (!locked)
1935 		mtx_unlock(IOAT_REFLK);
1936 }
1937 
1938 static inline void
1939 ioat_put(struct ioat_softc *ioat, enum ioat_ref_kind kind)
1940 {
1941 
1942 	ioat_putn(ioat, 1, kind);
1943 }
1944 
1945 static void
1946 ioat_drain_locked(struct ioat_softc *ioat)
1947 {
1948 
1949 	mtx_assert(IOAT_REFLK, MA_OWNED);
1950 	while (ioat->refcnt > 0)
1951 		msleep(IOAT_REFLK, IOAT_REFLK, 0, "ioat_drain", 0);
1952 }
1953 
1954 #ifdef DDB
1955 #define	_db_show_lock(lo)	LOCK_CLASS(lo)->lc_ddb_show(lo)
1956 #define	db_show_lock(lk)	_db_show_lock(&(lk)->lock_object)
1957 DB_SHOW_COMMAND(ioat, db_show_ioat)
1958 {
1959 	struct ioat_softc *sc;
1960 	unsigned idx;
1961 
1962 	if (!have_addr)
1963 		goto usage;
1964 	idx = (unsigned)addr;
1965 	if (idx >= ioat_channel_index)
1966 		goto usage;
1967 
1968 	sc = ioat_channel[idx];
1969 	db_printf("ioat softc at %p\n", sc);
1970 	if (sc == NULL)
1971 		return;
1972 
1973 	db_printf(" version: %d\n", sc->version);
1974 	db_printf(" chan_idx: %u\n", sc->chan_idx);
1975 	db_printf(" submit_lock: ");
1976 	db_show_lock(&sc->submit_lock);
1977 
1978 	db_printf(" capabilities: %b\n", (int)sc->capabilities,
1979 	    IOAT_DMACAP_STR);
1980 	db_printf(" cached_intrdelay: %u\n", sc->cached_intrdelay);
1981 	db_printf(" *comp_update: 0x%jx\n", (uintmax_t)*sc->comp_update);
1982 
1983 	db_printf(" poll_timer:\n");
1984 	db_printf("  c_time: %ju\n", (uintmax_t)sc->poll_timer.c_time);
1985 	db_printf("  c_arg: %p\n", sc->poll_timer.c_arg);
1986 	db_printf("  c_func: %p\n", sc->poll_timer.c_func);
1987 	db_printf("  c_lock: %p\n", sc->poll_timer.c_lock);
1988 	db_printf("  c_flags: 0x%x\n", (unsigned)sc->poll_timer.c_flags);
1989 
1990 	db_printf(" quiescing: %d\n", (int)sc->quiescing);
1991 	db_printf(" destroying: %d\n", (int)sc->destroying);
1992 	db_printf(" is_submitter_processing: %d\n",
1993 	    (int)sc->is_submitter_processing);
1994 	db_printf(" is_completion_pending: %d\n", (int)sc->is_completion_pending);
1995 	db_printf(" is_reset_pending: %d\n", (int)sc->is_reset_pending);
1996 	db_printf(" is_channel_running: %d\n", (int)sc->is_channel_running);
1997 	db_printf(" intrdelay_supported: %d\n", (int)sc->intrdelay_supported);
1998 	db_printf(" resetting: %d\n", (int)sc->resetting);
1999 
2000 	db_printf(" head: %u\n", sc->head);
2001 	db_printf(" tail: %u\n", sc->tail);
2002 	db_printf(" hw_head: %u\n", sc->hw_head);
2003 	db_printf(" ring_size_order: %u\n", sc->ring_size_order);
2004 	db_printf(" last_seen: 0x%lx\n", sc->last_seen);
2005 	db_printf(" ring: %p\n", sc->ring);
2006 	db_printf(" descriptors: %p\n", sc->hw_desc_ring);
2007 	db_printf(" descriptors (phys): 0x%jx\n",
2008 	    (uintmax_t)sc->hw_desc_bus_addr);
2009 
2010 	db_printf("  ring[%u] (tail):\n", sc->tail %
2011 	    (1 << sc->ring_size_order));
2012 	db_printf("   id: %u\n", ioat_get_ring_entry(sc, sc->tail)->id);
2013 	db_printf("   addr: 0x%lx\n",
2014 	    RING_PHYS_ADDR(sc, sc->tail));
2015 	db_printf("   next: 0x%lx\n",
2016 	     ioat_get_descriptor(sc, sc->tail)->generic.next);
2017 
2018 	db_printf("  ring[%u] (head - 1):\n", (sc->head - 1) %
2019 	    (1 << sc->ring_size_order));
2020 	db_printf("   id: %u\n", ioat_get_ring_entry(sc, sc->head - 1)->id);
2021 	db_printf("   addr: 0x%lx\n",
2022 	    RING_PHYS_ADDR(sc, sc->head - 1));
2023 	db_printf("   next: 0x%lx\n",
2024 	     ioat_get_descriptor(sc, sc->head - 1)->generic.next);
2025 
2026 	db_printf("  ring[%u] (head):\n", (sc->head) %
2027 	    (1 << sc->ring_size_order));
2028 	db_printf("   id: %u\n", ioat_get_ring_entry(sc, sc->head)->id);
2029 	db_printf("   addr: 0x%lx\n",
2030 	    RING_PHYS_ADDR(sc, sc->head));
2031 	db_printf("   next: 0x%lx\n",
2032 	     ioat_get_descriptor(sc, sc->head)->generic.next);
2033 
2034 	for (idx = 0; idx < (1 << sc->ring_size_order); idx++)
2035 		if ((*sc->comp_update & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_MASK)
2036 		    == RING_PHYS_ADDR(sc, idx))
2037 			db_printf("  ring[%u] == hardware tail\n", idx);
2038 
2039 	db_printf(" cleanup_lock: ");
2040 	db_show_lock(&sc->cleanup_lock);
2041 
2042 	db_printf(" refcnt: %u\n", sc->refcnt);
2043 #ifdef INVARIANTS
2044 	CTASSERT(IOAT_NUM_REF_KINDS == 2);
2045 	db_printf(" refkinds: [ENG=%u, DESCR=%u]\n", sc->refkinds[0],
2046 	    sc->refkinds[1]);
2047 #endif
2048 	db_printf(" stats:\n");
2049 	db_printf("  interrupts: %lu\n", sc->stats.interrupts);
2050 	db_printf("  descriptors_processed: %lu\n", sc->stats.descriptors_processed);
2051 	db_printf("  descriptors_error: %lu\n", sc->stats.descriptors_error);
2052 	db_printf("  descriptors_submitted: %lu\n", sc->stats.descriptors_submitted);
2053 
2054 	db_printf("  channel_halts: %u\n", sc->stats.channel_halts);
2055 	db_printf("  last_halt_chanerr: %u\n", sc->stats.last_halt_chanerr);
2056 
2057 	if (db_pager_quit)
2058 		return;
2059 
2060 	db_printf(" hw status:\n");
2061 	db_printf("  status: 0x%lx\n", ioat_get_chansts(sc));
2062 	db_printf("  chanctrl: 0x%x\n",
2063 	    (unsigned)ioat_read_2(sc, IOAT_CHANCTRL_OFFSET));
2064 	db_printf("  chancmd: 0x%x\n",
2065 	    (unsigned)ioat_read_1(sc, IOAT_CHANCMD_OFFSET));
2066 	db_printf("  dmacount: 0x%x\n",
2067 	    (unsigned)ioat_read_2(sc, IOAT_DMACOUNT_OFFSET));
2068 	db_printf("  chainaddr: 0x%lx\n",
2069 	    ioat_read_double_4(sc, IOAT_CHAINADDR_OFFSET_LOW));
2070 	db_printf("  chancmp: 0x%lx\n",
2071 	    ioat_read_double_4(sc, IOAT_CHANCMP_OFFSET_LOW));
2072 	db_printf("  chanerr: %b\n",
2073 	    (int)ioat_read_4(sc, IOAT_CHANERR_OFFSET), IOAT_CHANERR_STR);
2074 	return;
2075 usage:
2076 	db_printf("usage: show ioat <0-%u>\n", ioat_channel_index);
2077 	return;
2078 }
2079 #endif /* DDB */
2080