xref: /freebsd/sys/dev/ioat/ioat.c (revision 1ce1c6895245648ba022f7187df1626904dc1f89)
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 <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/conf.h>
34 #include <sys/ioccom.h>
35 #include <sys/kernel.h>
36 #include <sys/lock.h>
37 #include <sys/malloc.h>
38 #include <sys/module.h>
39 #include <sys/mutex.h>
40 #include <sys/rman.h>
41 #include <sys/sbuf.h>
42 #include <sys/sysctl.h>
43 #include <sys/time.h>
44 #include <dev/pci/pcireg.h>
45 #include <dev/pci/pcivar.h>
46 #include <machine/bus.h>
47 #include <machine/resource.h>
48 #include <machine/stdarg.h>
49 
50 #include "ioat.h"
51 #include "ioat_hw.h"
52 #include "ioat_internal.h"
53 
54 #define	IOAT_INTR_TIMO	(hz / 10)
55 #define	IOAT_REFLK	(&ioat->submit_lock)
56 
57 static int ioat_probe(device_t device);
58 static int ioat_attach(device_t device);
59 static int ioat_detach(device_t device);
60 static int ioat_setup_intr(struct ioat_softc *ioat);
61 static int ioat_teardown_intr(struct ioat_softc *ioat);
62 static int ioat3_attach(device_t device);
63 static int ioat_start_channel(struct ioat_softc *ioat);
64 static int ioat_map_pci_bar(struct ioat_softc *ioat);
65 static void ioat_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nseg,
66     int error);
67 static void ioat_interrupt_handler(void *arg);
68 static boolean_t ioat_model_resets_msix(struct ioat_softc *ioat);
69 static int chanerr_to_errno(uint32_t);
70 static void ioat_process_events(struct ioat_softc *ioat);
71 static inline uint32_t ioat_get_active(struct ioat_softc *ioat);
72 static inline uint32_t ioat_get_ring_space(struct ioat_softc *ioat);
73 static void ioat_free_ring(struct ioat_softc *, uint32_t size,
74     struct ioat_descriptor **);
75 static void ioat_free_ring_entry(struct ioat_softc *ioat,
76     struct ioat_descriptor *desc);
77 static struct ioat_descriptor *ioat_alloc_ring_entry(struct ioat_softc *,
78     int mflags);
79 static int ioat_reserve_space(struct ioat_softc *, uint32_t, int mflags);
80 static struct ioat_descriptor *ioat_get_ring_entry(struct ioat_softc *ioat,
81     uint32_t index);
82 static struct ioat_descriptor **ioat_prealloc_ring(struct ioat_softc *,
83     uint32_t size, boolean_t need_dscr, int mflags);
84 static int ring_grow(struct ioat_softc *, uint32_t oldorder,
85     struct ioat_descriptor **);
86 static int ring_shrink(struct ioat_softc *, uint32_t oldorder,
87     struct ioat_descriptor **);
88 static void ioat_halted_debug(struct ioat_softc *, uint32_t);
89 static void ioat_timer_callback(void *arg);
90 static void dump_descriptor(void *hw_desc);
91 static void ioat_submit_single(struct ioat_softc *ioat);
92 static void ioat_comp_update_map(void *arg, bus_dma_segment_t *seg, int nseg,
93     int error);
94 static int ioat_reset_hw(struct ioat_softc *ioat);
95 static void ioat_setup_sysctl(device_t device);
96 static int sysctl_handle_reset(SYSCTL_HANDLER_ARGS);
97 static inline struct ioat_softc *ioat_get(struct ioat_softc *,
98     enum ioat_ref_kind);
99 static inline void ioat_put(struct ioat_softc *, enum ioat_ref_kind);
100 static inline void _ioat_putn(struct ioat_softc *, uint32_t,
101     enum ioat_ref_kind, boolean_t);
102 static inline void ioat_putn(struct ioat_softc *, uint32_t,
103     enum ioat_ref_kind);
104 static inline void ioat_putn_locked(struct ioat_softc *, uint32_t,
105     enum ioat_ref_kind);
106 static void ioat_drain_locked(struct ioat_softc *);
107 
108 #define	ioat_log_message(v, ...) do {					\
109 	if ((v) <= g_ioat_debug_level) {				\
110 		device_printf(ioat->device, __VA_ARGS__);		\
111 	}								\
112 } while (0)
113 
114 MALLOC_DEFINE(M_IOAT, "ioat", "ioat driver memory allocations");
115 SYSCTL_NODE(_hw, OID_AUTO, ioat, CTLFLAG_RD, 0, "ioat node");
116 
117 static int g_force_legacy_interrupts;
118 SYSCTL_INT(_hw_ioat, OID_AUTO, force_legacy_interrupts, CTLFLAG_RDTUN,
119     &g_force_legacy_interrupts, 0, "Set to non-zero to force MSI-X disabled");
120 
121 int g_ioat_debug_level = 0;
122 SYSCTL_INT(_hw_ioat, OID_AUTO, debug_level, CTLFLAG_RWTUN, &g_ioat_debug_level,
123     0, "Set log level (0-3) for ioat(4). Higher is more verbose.");
124 
125 /*
126  * OS <-> Driver interface structures
127  */
128 static device_method_t ioat_pci_methods[] = {
129 	/* Device interface */
130 	DEVMETHOD(device_probe,     ioat_probe),
131 	DEVMETHOD(device_attach,    ioat_attach),
132 	DEVMETHOD(device_detach,    ioat_detach),
133 	{ 0, 0 }
134 };
135 
136 static driver_t ioat_pci_driver = {
137 	"ioat",
138 	ioat_pci_methods,
139 	sizeof(struct ioat_softc),
140 };
141 
142 static devclass_t ioat_devclass;
143 DRIVER_MODULE(ioat, pci, ioat_pci_driver, ioat_devclass, 0, 0);
144 MODULE_VERSION(ioat, 1);
145 
146 /*
147  * Private data structures
148  */
149 static struct ioat_softc *ioat_channel[IOAT_MAX_CHANNELS];
150 static int ioat_channel_index = 0;
151 SYSCTL_INT(_hw_ioat, OID_AUTO, channels, CTLFLAG_RD, &ioat_channel_index, 0,
152     "Number of IOAT channels attached");
153 
154 static struct _pcsid
155 {
156 	u_int32_t   type;
157 	const char  *desc;
158 } pci_ids[] = {
159 	{ 0x34308086, "TBG IOAT Ch0" },
160 	{ 0x34318086, "TBG IOAT Ch1" },
161 	{ 0x34328086, "TBG IOAT Ch2" },
162 	{ 0x34338086, "TBG IOAT Ch3" },
163 	{ 0x34298086, "TBG IOAT Ch4" },
164 	{ 0x342a8086, "TBG IOAT Ch5" },
165 	{ 0x342b8086, "TBG IOAT Ch6" },
166 	{ 0x342c8086, "TBG IOAT Ch7" },
167 
168 	{ 0x37108086, "JSF IOAT Ch0" },
169 	{ 0x37118086, "JSF IOAT Ch1" },
170 	{ 0x37128086, "JSF IOAT Ch2" },
171 	{ 0x37138086, "JSF IOAT Ch3" },
172 	{ 0x37148086, "JSF IOAT Ch4" },
173 	{ 0x37158086, "JSF IOAT Ch5" },
174 	{ 0x37168086, "JSF IOAT Ch6" },
175 	{ 0x37178086, "JSF IOAT Ch7" },
176 	{ 0x37188086, "JSF IOAT Ch0 (RAID)" },
177 	{ 0x37198086, "JSF IOAT Ch1 (RAID)" },
178 
179 	{ 0x3c208086, "SNB IOAT Ch0" },
180 	{ 0x3c218086, "SNB IOAT Ch1" },
181 	{ 0x3c228086, "SNB IOAT Ch2" },
182 	{ 0x3c238086, "SNB IOAT Ch3" },
183 	{ 0x3c248086, "SNB IOAT Ch4" },
184 	{ 0x3c258086, "SNB IOAT Ch5" },
185 	{ 0x3c268086, "SNB IOAT Ch6" },
186 	{ 0x3c278086, "SNB IOAT Ch7" },
187 	{ 0x3c2e8086, "SNB IOAT Ch0 (RAID)" },
188 	{ 0x3c2f8086, "SNB IOAT Ch1 (RAID)" },
189 
190 	{ 0x0e208086, "IVB IOAT Ch0" },
191 	{ 0x0e218086, "IVB IOAT Ch1" },
192 	{ 0x0e228086, "IVB IOAT Ch2" },
193 	{ 0x0e238086, "IVB IOAT Ch3" },
194 	{ 0x0e248086, "IVB IOAT Ch4" },
195 	{ 0x0e258086, "IVB IOAT Ch5" },
196 	{ 0x0e268086, "IVB IOAT Ch6" },
197 	{ 0x0e278086, "IVB IOAT Ch7" },
198 	{ 0x0e2e8086, "IVB IOAT Ch0 (RAID)" },
199 	{ 0x0e2f8086, "IVB IOAT Ch1 (RAID)" },
200 
201 	{ 0x2f208086, "HSW IOAT Ch0" },
202 	{ 0x2f218086, "HSW IOAT Ch1" },
203 	{ 0x2f228086, "HSW IOAT Ch2" },
204 	{ 0x2f238086, "HSW IOAT Ch3" },
205 	{ 0x2f248086, "HSW IOAT Ch4" },
206 	{ 0x2f258086, "HSW IOAT Ch5" },
207 	{ 0x2f268086, "HSW IOAT Ch6" },
208 	{ 0x2f278086, "HSW IOAT Ch7" },
209 	{ 0x2f2e8086, "HSW IOAT Ch0 (RAID)" },
210 	{ 0x2f2f8086, "HSW IOAT Ch1 (RAID)" },
211 
212 	{ 0x0c508086, "BWD IOAT Ch0" },
213 	{ 0x0c518086, "BWD IOAT Ch1" },
214 	{ 0x0c528086, "BWD IOAT Ch2" },
215 	{ 0x0c538086, "BWD IOAT Ch3" },
216 
217 	{ 0x6f508086, "BDXDE IOAT Ch0" },
218 	{ 0x6f518086, "BDXDE IOAT Ch1" },
219 	{ 0x6f528086, "BDXDE IOAT Ch2" },
220 	{ 0x6f538086, "BDXDE IOAT Ch3" },
221 
222 	{ 0x6f208086, "BDX IOAT Ch0" },
223 	{ 0x6f218086, "BDX IOAT Ch1" },
224 	{ 0x6f228086, "BDX IOAT Ch2" },
225 	{ 0x6f238086, "BDX IOAT Ch3" },
226 	{ 0x6f248086, "BDX IOAT Ch4" },
227 	{ 0x6f258086, "BDX IOAT Ch5" },
228 	{ 0x6f268086, "BDX IOAT Ch6" },
229 	{ 0x6f278086, "BDX IOAT Ch7" },
230 	{ 0x6f2e8086, "BDX IOAT Ch0 (RAID)" },
231 	{ 0x6f2f8086, "BDX IOAT Ch1 (RAID)" },
232 
233 	{ 0x00000000, NULL           }
234 };
235 
236 /*
237  * OS <-> Driver linkage functions
238  */
239 static int
240 ioat_probe(device_t device)
241 {
242 	struct _pcsid *ep;
243 	u_int32_t type;
244 
245 	type = pci_get_devid(device);
246 	for (ep = pci_ids; ep->type; ep++) {
247 		if (ep->type == type) {
248 			device_set_desc(device, ep->desc);
249 			return (0);
250 		}
251 	}
252 	return (ENXIO);
253 }
254 
255 static int
256 ioat_attach(device_t device)
257 {
258 	struct ioat_softc *ioat;
259 	int error;
260 
261 	ioat = DEVICE2SOFTC(device);
262 	ioat->device = device;
263 
264 	error = ioat_map_pci_bar(ioat);
265 	if (error != 0)
266 		goto err;
267 
268 	ioat->version = ioat_read_cbver(ioat);
269 	if (ioat->version < IOAT_VER_3_0) {
270 		error = ENODEV;
271 		goto err;
272 	}
273 
274 	error = ioat3_attach(device);
275 	if (error != 0)
276 		goto err;
277 
278 	error = pci_enable_busmaster(device);
279 	if (error != 0)
280 		goto err;
281 
282 	error = ioat_setup_intr(ioat);
283 	if (error != 0)
284 		goto err;
285 
286 	error = ioat_reset_hw(ioat);
287 	if (error != 0)
288 		goto err;
289 
290 	ioat_process_events(ioat);
291 	ioat_setup_sysctl(device);
292 
293 	ioat->chan_idx = ioat_channel_index;
294 	ioat_channel[ioat_channel_index++] = ioat;
295 	ioat_test_attach();
296 
297 err:
298 	if (error != 0)
299 		ioat_detach(device);
300 	return (error);
301 }
302 
303 static int
304 ioat_detach(device_t device)
305 {
306 	struct ioat_softc *ioat;
307 
308 	ioat = DEVICE2SOFTC(device);
309 
310 	ioat_test_detach();
311 
312 	mtx_lock(IOAT_REFLK);
313 	ioat->quiescing = TRUE;
314 	ioat_channel[ioat->chan_idx] = NULL;
315 
316 	ioat_drain_locked(ioat);
317 	mtx_unlock(IOAT_REFLK);
318 
319 	ioat_teardown_intr(ioat);
320 	callout_drain(&ioat->timer);
321 
322 	pci_disable_busmaster(device);
323 
324 	if (ioat->pci_resource != NULL)
325 		bus_release_resource(device, SYS_RES_MEMORY,
326 		    ioat->pci_resource_id, ioat->pci_resource);
327 
328 	if (ioat->ring != NULL)
329 		ioat_free_ring(ioat, 1 << ioat->ring_size_order, ioat->ring);
330 
331 	if (ioat->comp_update != NULL) {
332 		bus_dmamap_unload(ioat->comp_update_tag, ioat->comp_update_map);
333 		bus_dmamem_free(ioat->comp_update_tag, ioat->comp_update,
334 		    ioat->comp_update_map);
335 		bus_dma_tag_destroy(ioat->comp_update_tag);
336 	}
337 
338 	bus_dma_tag_destroy(ioat->hw_desc_tag);
339 
340 	return (0);
341 }
342 
343 static int
344 ioat_teardown_intr(struct ioat_softc *ioat)
345 {
346 
347 	if (ioat->tag != NULL)
348 		bus_teardown_intr(ioat->device, ioat->res, ioat->tag);
349 
350 	if (ioat->res != NULL)
351 		bus_release_resource(ioat->device, SYS_RES_IRQ,
352 		    rman_get_rid(ioat->res), ioat->res);
353 
354 	pci_release_msi(ioat->device);
355 	return (0);
356 }
357 
358 static int
359 ioat_start_channel(struct ioat_softc *ioat)
360 {
361 	uint64_t status;
362 	uint32_t chanerr;
363 	int i;
364 
365 	ioat_acquire(&ioat->dmaengine);
366 	ioat_null(&ioat->dmaengine, NULL, NULL, 0);
367 	ioat_release(&ioat->dmaengine);
368 
369 	for (i = 0; i < 100; i++) {
370 		DELAY(1);
371 		status = ioat_get_chansts(ioat);
372 		if (is_ioat_idle(status))
373 			return (0);
374 	}
375 
376 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
377 	ioat_log_message(0, "could not start channel: "
378 	    "status = %#jx error = %b\n", (uintmax_t)status, (int)chanerr,
379 	    IOAT_CHANERR_STR);
380 	return (ENXIO);
381 }
382 
383 /*
384  * Initialize Hardware
385  */
386 static int
387 ioat3_attach(device_t device)
388 {
389 	struct ioat_softc *ioat;
390 	struct ioat_descriptor **ring;
391 	struct ioat_descriptor *next;
392 	struct ioat_dma_hw_descriptor *dma_hw_desc;
393 	int i, num_descriptors;
394 	int error;
395 	uint8_t xfercap;
396 
397 	error = 0;
398 	ioat = DEVICE2SOFTC(device);
399 	ioat->capabilities = ioat_read_dmacapability(ioat);
400 
401 	ioat_log_message(1, "Capabilities: %b\n", (int)ioat->capabilities,
402 	    IOAT_DMACAP_STR);
403 
404 	xfercap = ioat_read_xfercap(ioat);
405 	ioat->max_xfer_size = 1 << xfercap;
406 
407 	/* TODO: need to check DCA here if we ever do XOR/PQ */
408 
409 	mtx_init(&ioat->submit_lock, "ioat_submit", NULL, MTX_DEF);
410 	mtx_init(&ioat->cleanup_lock, "ioat_cleanup", NULL, MTX_DEF);
411 	callout_init(&ioat->timer, 1);
412 
413 	/* Establish lock order for Witness */
414 	mtx_lock(&ioat->submit_lock);
415 	mtx_lock(&ioat->cleanup_lock);
416 	mtx_unlock(&ioat->cleanup_lock);
417 	mtx_unlock(&ioat->submit_lock);
418 
419 	ioat->is_resize_pending = FALSE;
420 	ioat->is_completion_pending = FALSE;
421 	ioat->is_reset_pending = FALSE;
422 	ioat->is_channel_running = FALSE;
423 
424 	bus_dma_tag_create(bus_get_dma_tag(ioat->device), sizeof(uint64_t), 0x0,
425 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
426 	    sizeof(uint64_t), 1, sizeof(uint64_t), 0, NULL, NULL,
427 	    &ioat->comp_update_tag);
428 
429 	error = bus_dmamem_alloc(ioat->comp_update_tag,
430 	    (void **)&ioat->comp_update, BUS_DMA_ZERO, &ioat->comp_update_map);
431 	if (ioat->comp_update == NULL)
432 		return (ENOMEM);
433 
434 	error = bus_dmamap_load(ioat->comp_update_tag, ioat->comp_update_map,
435 	    ioat->comp_update, sizeof(uint64_t), ioat_comp_update_map, ioat,
436 	    0);
437 	if (error != 0)
438 		return (error);
439 
440 	ioat->ring_size_order = IOAT_MIN_ORDER;
441 
442 	num_descriptors = 1 << ioat->ring_size_order;
443 
444 	bus_dma_tag_create(bus_get_dma_tag(ioat->device), 0x40, 0x0,
445 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
446 	    sizeof(struct ioat_dma_hw_descriptor), 1,
447 	    sizeof(struct ioat_dma_hw_descriptor), 0, NULL, NULL,
448 	    &ioat->hw_desc_tag);
449 
450 	ioat->ring = malloc(num_descriptors * sizeof(*ring), M_IOAT,
451 	    M_ZERO | M_WAITOK);
452 	if (ioat->ring == NULL)
453 		return (ENOMEM);
454 
455 	ring = ioat->ring;
456 	for (i = 0; i < num_descriptors; i++) {
457 		ring[i] = ioat_alloc_ring_entry(ioat, M_WAITOK);
458 		if (ring[i] == NULL)
459 			return (ENOMEM);
460 
461 		ring[i]->id = i;
462 	}
463 
464 	for (i = 0; i < num_descriptors - 1; i++) {
465 		next = ring[i + 1];
466 		dma_hw_desc = ring[i]->u.dma;
467 
468 		dma_hw_desc->next = next->hw_desc_bus_addr;
469 	}
470 
471 	ring[i]->u.dma->next = ring[0]->hw_desc_bus_addr;
472 
473 	ioat->head = ioat->hw_head = 0;
474 	ioat->tail = 0;
475 	ioat->last_seen = 0;
476 	return (0);
477 }
478 
479 static int
480 ioat_map_pci_bar(struct ioat_softc *ioat)
481 {
482 
483 	ioat->pci_resource_id = PCIR_BAR(0);
484 	ioat->pci_resource = bus_alloc_resource_any(ioat->device,
485 	    SYS_RES_MEMORY, &ioat->pci_resource_id, RF_ACTIVE);
486 
487 	if (ioat->pci_resource == NULL) {
488 		ioat_log_message(0, "unable to allocate pci resource\n");
489 		return (ENODEV);
490 	}
491 
492 	ioat->pci_bus_tag = rman_get_bustag(ioat->pci_resource);
493 	ioat->pci_bus_handle = rman_get_bushandle(ioat->pci_resource);
494 	return (0);
495 }
496 
497 static void
498 ioat_comp_update_map(void *arg, bus_dma_segment_t *seg, int nseg, int error)
499 {
500 	struct ioat_softc *ioat = arg;
501 
502 	KASSERT(error == 0, ("%s: error:%d", __func__, error));
503 	ioat->comp_update_bus_addr = seg[0].ds_addr;
504 }
505 
506 static void
507 ioat_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nseg, int error)
508 {
509 	bus_addr_t *baddr;
510 
511 	KASSERT(error == 0, ("%s: error:%d", __func__, error));
512 	baddr = arg;
513 	*baddr = segs->ds_addr;
514 }
515 
516 /*
517  * Interrupt setup and handlers
518  */
519 static int
520 ioat_setup_intr(struct ioat_softc *ioat)
521 {
522 	uint32_t num_vectors;
523 	int error;
524 	boolean_t use_msix;
525 	boolean_t force_legacy_interrupts;
526 
527 	use_msix = FALSE;
528 	force_legacy_interrupts = FALSE;
529 
530 	if (!g_force_legacy_interrupts && pci_msix_count(ioat->device) >= 1) {
531 		num_vectors = 1;
532 		pci_alloc_msix(ioat->device, &num_vectors);
533 		if (num_vectors == 1)
534 			use_msix = TRUE;
535 	}
536 
537 	if (use_msix) {
538 		ioat->rid = 1;
539 		ioat->res = bus_alloc_resource_any(ioat->device, SYS_RES_IRQ,
540 		    &ioat->rid, RF_ACTIVE);
541 	} else {
542 		ioat->rid = 0;
543 		ioat->res = bus_alloc_resource_any(ioat->device, SYS_RES_IRQ,
544 		    &ioat->rid, RF_SHAREABLE | RF_ACTIVE);
545 	}
546 	if (ioat->res == NULL) {
547 		ioat_log_message(0, "bus_alloc_resource failed\n");
548 		return (ENOMEM);
549 	}
550 
551 	ioat->tag = NULL;
552 	error = bus_setup_intr(ioat->device, ioat->res, INTR_MPSAFE |
553 	    INTR_TYPE_MISC, NULL, ioat_interrupt_handler, ioat, &ioat->tag);
554 	if (error != 0) {
555 		ioat_log_message(0, "bus_setup_intr failed\n");
556 		return (error);
557 	}
558 
559 	ioat_write_intrctrl(ioat, IOAT_INTRCTRL_MASTER_INT_EN);
560 	return (0);
561 }
562 
563 static boolean_t
564 ioat_model_resets_msix(struct ioat_softc *ioat)
565 {
566 	u_int32_t pciid;
567 
568 	pciid = pci_get_devid(ioat->device);
569 	switch (pciid) {
570 		/* BWD: */
571 	case 0x0c508086:
572 	case 0x0c518086:
573 	case 0x0c528086:
574 	case 0x0c538086:
575 		/* BDXDE: */
576 	case 0x6f508086:
577 	case 0x6f518086:
578 	case 0x6f528086:
579 	case 0x6f538086:
580 		return (TRUE);
581 	}
582 
583 	return (FALSE);
584 }
585 
586 static void
587 ioat_interrupt_handler(void *arg)
588 {
589 	struct ioat_softc *ioat = arg;
590 
591 	ioat_process_events(ioat);
592 }
593 
594 static int
595 chanerr_to_errno(uint32_t chanerr)
596 {
597 
598 	if (chanerr == 0)
599 		return (0);
600 	if ((chanerr & (IOAT_CHANERR_XSADDERR | IOAT_CHANERR_XDADDERR)) != 0)
601 		return (EFAULT);
602 	if ((chanerr & (IOAT_CHANERR_RDERR | IOAT_CHANERR_WDERR)) != 0)
603 		return (EIO);
604 	/* This one is probably our fault: */
605 	if ((chanerr & IOAT_CHANERR_NDADDERR) != 0)
606 		return (EIO);
607 	return (EIO);
608 }
609 
610 static void
611 ioat_process_events(struct ioat_softc *ioat)
612 {
613 	struct ioat_descriptor *desc;
614 	struct bus_dmadesc *dmadesc;
615 	uint64_t comp_update, status;
616 	uint32_t completed, chanerr;
617 	int error;
618 
619 	mtx_lock(&ioat->cleanup_lock);
620 
621 	completed = 0;
622 	comp_update = *ioat->comp_update;
623 	status = comp_update & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_MASK;
624 
625 	CTR0(KTR_IOAT, __func__);
626 
627 	if (status == ioat->last_seen)
628 		goto out;
629 
630 	while (1) {
631 		desc = ioat_get_ring_entry(ioat, ioat->tail);
632 		dmadesc = &desc->bus_dmadesc;
633 		CTR1(KTR_IOAT, "completing desc %d", ioat->tail);
634 
635 		if (dmadesc->callback_fn != NULL)
636 			dmadesc->callback_fn(dmadesc->callback_arg, 0);
637 
638 		completed++;
639 		ioat->tail++;
640 		if (desc->hw_desc_bus_addr == status)
641 			break;
642 	}
643 
644 	ioat->last_seen = desc->hw_desc_bus_addr;
645 
646 	if (ioat->head == ioat->tail) {
647 		ioat->is_completion_pending = FALSE;
648 		callout_reset(&ioat->timer, IOAT_INTR_TIMO,
649 		    ioat_timer_callback, ioat);
650 	}
651 
652 out:
653 	ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
654 	mtx_unlock(&ioat->cleanup_lock);
655 
656 	ioat_putn(ioat, completed, IOAT_ACTIVE_DESCR_REF);
657 	wakeup(&ioat->tail);
658 
659 	if (!is_ioat_halted(comp_update))
660 		return;
661 
662 	/*
663 	 * Fatal programming error on this DMA channel.  Flush any outstanding
664 	 * work with error status and restart the engine.
665 	 */
666 	ioat_log_message(0, "Channel halted due to fatal programming error\n");
667 	mtx_lock(&ioat->submit_lock);
668 	mtx_lock(&ioat->cleanup_lock);
669 	ioat->quiescing = TRUE;
670 
671 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
672 	ioat_halted_debug(ioat, chanerr);
673 
674 	while (ioat_get_active(ioat) > 0) {
675 		desc = ioat_get_ring_entry(ioat, ioat->tail);
676 		dmadesc = &desc->bus_dmadesc;
677 		CTR1(KTR_IOAT, "completing err desc %d", ioat->tail);
678 
679 		if (dmadesc->callback_fn != NULL)
680 			dmadesc->callback_fn(dmadesc->callback_arg,
681 			    chanerr_to_errno(chanerr));
682 
683 		ioat_putn_locked(ioat, 1, IOAT_ACTIVE_DESCR_REF);
684 		ioat->tail++;
685 	}
686 
687 	/* Clear error status */
688 	ioat_write_4(ioat, IOAT_CHANERR_OFFSET, chanerr);
689 
690 	mtx_unlock(&ioat->cleanup_lock);
691 	mtx_unlock(&ioat->submit_lock);
692 
693 	ioat_log_message(0, "Resetting channel to recover from error\n");
694 	error = ioat_reset_hw(ioat);
695 	KASSERT(error == 0, ("%s: reset failed: %d", __func__, error));
696 }
697 
698 /*
699  * User API functions
700  */
701 bus_dmaengine_t
702 ioat_get_dmaengine(uint32_t index)
703 {
704 	struct ioat_softc *sc;
705 
706 	if (index >= ioat_channel_index)
707 		return (NULL);
708 
709 	sc = ioat_channel[index];
710 	if (sc == NULL || sc->quiescing)
711 		return (NULL);
712 
713 	return (&ioat_get(sc, IOAT_DMAENGINE_REF)->dmaengine);
714 }
715 
716 void
717 ioat_put_dmaengine(bus_dmaengine_t dmaengine)
718 {
719 	struct ioat_softc *ioat;
720 
721 	ioat = to_ioat_softc(dmaengine);
722 	ioat_put(ioat, IOAT_DMAENGINE_REF);
723 }
724 
725 void
726 ioat_acquire(bus_dmaengine_t dmaengine)
727 {
728 	struct ioat_softc *ioat;
729 
730 	ioat = to_ioat_softc(dmaengine);
731 	mtx_lock(&ioat->submit_lock);
732 	CTR0(KTR_IOAT, __func__);
733 }
734 
735 void
736 ioat_release(bus_dmaengine_t dmaengine)
737 {
738 	struct ioat_softc *ioat;
739 
740 	ioat = to_ioat_softc(dmaengine);
741 	CTR0(KTR_IOAT, __func__);
742 	ioat_write_2(ioat, IOAT_DMACOUNT_OFFSET, (uint16_t)ioat->hw_head);
743 	mtx_unlock(&ioat->submit_lock);
744 }
745 
746 static struct ioat_descriptor *
747 ioat_op_generic(struct ioat_softc *ioat, uint8_t op,
748     uint32_t size, uint64_t src, uint64_t dst,
749     bus_dmaengine_callback_t callback_fn, void *callback_arg,
750     uint32_t flags)
751 {
752 	struct ioat_generic_hw_descriptor *hw_desc;
753 	struct ioat_descriptor *desc;
754 	int mflags;
755 
756 	mtx_assert(&ioat->submit_lock, MA_OWNED);
757 
758 	KASSERT((flags & ~DMA_ALL_FLAGS) == 0, ("Unrecognized flag(s): %#x",
759 		flags & ~DMA_ALL_FLAGS));
760 	if ((flags & DMA_NO_WAIT) != 0)
761 		mflags = M_NOWAIT;
762 	else
763 		mflags = M_WAITOK;
764 
765 	if (size > ioat->max_xfer_size) {
766 		ioat_log_message(0, "%s: max_xfer_size = %d, requested = %u\n",
767 		    __func__, ioat->max_xfer_size, (unsigned)size);
768 		return (NULL);
769 	}
770 
771 	if (ioat_reserve_space(ioat, 1, mflags) != 0)
772 		return (NULL);
773 
774 	desc = ioat_get_ring_entry(ioat, ioat->head);
775 	hw_desc = desc->u.generic;
776 
777 	hw_desc->u.control_raw = 0;
778 	hw_desc->u.control_generic.op = op;
779 	hw_desc->u.control_generic.completion_update = 1;
780 
781 	if ((flags & DMA_INT_EN) != 0)
782 		hw_desc->u.control_generic.int_enable = 1;
783 
784 	hw_desc->size = size;
785 	hw_desc->src_addr = src;
786 	hw_desc->dest_addr = dst;
787 
788 	desc->bus_dmadesc.callback_fn = callback_fn;
789 	desc->bus_dmadesc.callback_arg = callback_arg;
790 	return (desc);
791 }
792 
793 struct bus_dmadesc *
794 ioat_null(bus_dmaengine_t dmaengine, bus_dmaengine_callback_t callback_fn,
795     void *callback_arg, uint32_t flags)
796 {
797 	struct ioat_dma_hw_descriptor *hw_desc;
798 	struct ioat_descriptor *desc;
799 	struct ioat_softc *ioat;
800 
801 	CTR0(KTR_IOAT, __func__);
802 	ioat = to_ioat_softc(dmaengine);
803 
804 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, 8, 0, 0, callback_fn,
805 	    callback_arg, flags);
806 	if (desc == NULL)
807 		return (NULL);
808 
809 	hw_desc = desc->u.dma;
810 	hw_desc->u.control.null = 1;
811 	ioat_submit_single(ioat);
812 	return (&desc->bus_dmadesc);
813 }
814 
815 struct bus_dmadesc *
816 ioat_copy(bus_dmaengine_t dmaengine, bus_addr_t dst,
817     bus_addr_t src, bus_size_t len, bus_dmaengine_callback_t callback_fn,
818     void *callback_arg, uint32_t flags)
819 {
820 	struct ioat_dma_hw_descriptor *hw_desc;
821 	struct ioat_descriptor *desc;
822 	struct ioat_softc *ioat;
823 
824 	CTR0(KTR_IOAT, __func__);
825 	ioat = to_ioat_softc(dmaengine);
826 
827 	if (((src | dst) & (0xffffull << 48)) != 0) {
828 		ioat_log_message(0, "%s: High 16 bits of src/dst invalid\n",
829 		    __func__);
830 		return (NULL);
831 	}
832 
833 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, len, src, dst, callback_fn,
834 	    callback_arg, flags);
835 	if (desc == NULL)
836 		return (NULL);
837 
838 	hw_desc = desc->u.dma;
839 	if (g_ioat_debug_level >= 3)
840 		dump_descriptor(hw_desc);
841 
842 	ioat_submit_single(ioat);
843 	return (&desc->bus_dmadesc);
844 }
845 
846 struct bus_dmadesc *
847 ioat_copy_8k_aligned(bus_dmaengine_t dmaengine, bus_addr_t dst1,
848     bus_addr_t dst2, bus_addr_t src1, bus_addr_t src2,
849     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags)
850 {
851 	struct ioat_dma_hw_descriptor *hw_desc;
852 	struct ioat_descriptor *desc;
853 	struct ioat_softc *ioat;
854 
855 	CTR0(KTR_IOAT, __func__);
856 	ioat = to_ioat_softc(dmaengine);
857 
858 	if (((src1 | src2 | dst1 | dst2) & (0xffffull << 48)) != 0) {
859 		ioat_log_message(0, "%s: High 16 bits of src/dst invalid\n",
860 		    __func__);
861 		return (NULL);
862 	}
863 	if (((src1 | src2 | dst1 | dst2) & PAGE_MASK) != 0) {
864 		ioat_log_message(0, "%s: Addresses must be page-aligned\n",
865 		    __func__);
866 		return (NULL);
867 	}
868 
869 	desc = ioat_op_generic(ioat, IOAT_OP_COPY, 2 * PAGE_SIZE, src1, dst1,
870 	    callback_fn, callback_arg, flags);
871 	if (desc == NULL)
872 		return (NULL);
873 
874 	hw_desc = desc->u.dma;
875 	if (src2 != src1 + PAGE_SIZE) {
876 		hw_desc->u.control.src_page_break = 1;
877 		hw_desc->next_src_addr = src2;
878 	}
879 	if (dst2 != dst1 + PAGE_SIZE) {
880 		hw_desc->u.control.dest_page_break = 1;
881 		hw_desc->next_dest_addr = dst2;
882 	}
883 
884 	if (g_ioat_debug_level >= 3)
885 		dump_descriptor(hw_desc);
886 
887 	ioat_submit_single(ioat);
888 	return (&desc->bus_dmadesc);
889 }
890 
891 struct bus_dmadesc *
892 ioat_blockfill(bus_dmaengine_t dmaengine, bus_addr_t dst, uint64_t fillpattern,
893     bus_size_t len, bus_dmaengine_callback_t callback_fn, void *callback_arg,
894     uint32_t flags)
895 {
896 	struct ioat_fill_hw_descriptor *hw_desc;
897 	struct ioat_descriptor *desc;
898 	struct ioat_softc *ioat;
899 
900 	CTR0(KTR_IOAT, __func__);
901 	ioat = to_ioat_softc(dmaengine);
902 
903 	if ((ioat->capabilities & IOAT_DMACAP_BFILL) == 0) {
904 		ioat_log_message(0, "%s: Device lacks BFILL capability\n",
905 		    __func__);
906 		return (NULL);
907 	}
908 
909 	if ((dst & (0xffffull << 48)) != 0) {
910 		ioat_log_message(0, "%s: High 16 bits of dst invalid\n",
911 		    __func__);
912 		return (NULL);
913 	}
914 
915 	desc = ioat_op_generic(ioat, IOAT_OP_FILL, len, fillpattern, dst,
916 	    callback_fn, callback_arg, flags);
917 	if (desc == NULL)
918 		return (NULL);
919 
920 	hw_desc = desc->u.fill;
921 	if (g_ioat_debug_level >= 3)
922 		dump_descriptor(hw_desc);
923 
924 	ioat_submit_single(ioat);
925 	return (&desc->bus_dmadesc);
926 }
927 
928 /*
929  * Ring Management
930  */
931 static inline uint32_t
932 ioat_get_active(struct ioat_softc *ioat)
933 {
934 
935 	return ((ioat->head - ioat->tail) & ((1 << ioat->ring_size_order) - 1));
936 }
937 
938 static inline uint32_t
939 ioat_get_ring_space(struct ioat_softc *ioat)
940 {
941 
942 	return ((1 << ioat->ring_size_order) - ioat_get_active(ioat) - 1);
943 }
944 
945 static struct ioat_descriptor *
946 ioat_alloc_ring_entry(struct ioat_softc *ioat, int mflags)
947 {
948 	struct ioat_generic_hw_descriptor *hw_desc;
949 	struct ioat_descriptor *desc;
950 	int error, busdmaflag;
951 
952 	error = ENOMEM;
953 	hw_desc = NULL;
954 
955 	if ((mflags & M_WAITOK) != 0)
956 		busdmaflag = BUS_DMA_WAITOK;
957 	else
958 		busdmaflag = BUS_DMA_NOWAIT;
959 
960 	desc = malloc(sizeof(*desc), M_IOAT, mflags);
961 	if (desc == NULL)
962 		goto out;
963 
964 	bus_dmamem_alloc(ioat->hw_desc_tag, (void **)&hw_desc,
965 	    BUS_DMA_ZERO | busdmaflag, &ioat->hw_desc_map);
966 	if (hw_desc == NULL)
967 		goto out;
968 
969 	memset(&desc->bus_dmadesc, 0, sizeof(desc->bus_dmadesc));
970 	desc->u.generic = hw_desc;
971 
972 	error = bus_dmamap_load(ioat->hw_desc_tag, ioat->hw_desc_map, hw_desc,
973 	    sizeof(*hw_desc), ioat_dmamap_cb, &desc->hw_desc_bus_addr,
974 	    busdmaflag);
975 	if (error)
976 		goto out;
977 
978 out:
979 	if (error) {
980 		ioat_free_ring_entry(ioat, desc);
981 		return (NULL);
982 	}
983 	return (desc);
984 }
985 
986 static void
987 ioat_free_ring_entry(struct ioat_softc *ioat, struct ioat_descriptor *desc)
988 {
989 
990 	if (desc == NULL)
991 		return;
992 
993 	if (desc->u.generic)
994 		bus_dmamem_free(ioat->hw_desc_tag, desc->u.generic,
995 		    ioat->hw_desc_map);
996 	free(desc, M_IOAT);
997 }
998 
999 /*
1000  * Reserves space in this IOAT descriptor ring by ensuring enough slots remain
1001  * for 'num_descs'.
1002  *
1003  * If mflags contains M_WAITOK, blocks until enough space is available.
1004  *
1005  * Returns zero on success, or an errno on error.  If num_descs is beyond the
1006  * maximum ring size, returns EINVAl; if allocation would block and mflags
1007  * contains M_NOWAIT, returns EAGAIN.
1008  *
1009  * Must be called with the submit_lock held; returns with the lock held.  The
1010  * lock may be dropped to allocate the ring.
1011  *
1012  * (The submit_lock is needed to add any entries to the ring, so callers are
1013  * assured enough room is available.)
1014  */
1015 static int
1016 ioat_reserve_space(struct ioat_softc *ioat, uint32_t num_descs, int mflags)
1017 {
1018 	struct ioat_descriptor **new_ring;
1019 	uint32_t order;
1020 	int error;
1021 
1022 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1023 	error = 0;
1024 
1025 	if (num_descs < 1 || num_descs > (1 << IOAT_MAX_ORDER)) {
1026 		error = EINVAL;
1027 		goto out;
1028 	}
1029 	if (ioat->quiescing) {
1030 		error = ENXIO;
1031 		goto out;
1032 	}
1033 
1034 	for (;;) {
1035 		if (ioat_get_ring_space(ioat) >= num_descs)
1036 			goto out;
1037 
1038 		order = ioat->ring_size_order;
1039 		if (ioat->is_resize_pending || order == IOAT_MAX_ORDER) {
1040 			if ((mflags & M_WAITOK) != 0) {
1041 				msleep(&ioat->tail, &ioat->submit_lock, 0,
1042 				    "ioat_rsz", 0);
1043 				continue;
1044 			}
1045 
1046 			error = EAGAIN;
1047 			break;
1048 		}
1049 
1050 		ioat->is_resize_pending = TRUE;
1051 		for (;;) {
1052 			mtx_unlock(&ioat->submit_lock);
1053 
1054 			new_ring = ioat_prealloc_ring(ioat, 1 << (order + 1),
1055 			    TRUE, mflags);
1056 
1057 			mtx_lock(&ioat->submit_lock);
1058 			KASSERT(ioat->ring_size_order == order,
1059 			    ("is_resize_pending should protect order"));
1060 
1061 			if (new_ring == NULL) {
1062 				KASSERT((mflags & M_WAITOK) == 0,
1063 				    ("allocation failed"));
1064 				error = EAGAIN;
1065 				break;
1066 			}
1067 
1068 			error = ring_grow(ioat, order, new_ring);
1069 			if (error == 0)
1070 				break;
1071 		}
1072 		ioat->is_resize_pending = FALSE;
1073 		wakeup(&ioat->tail);
1074 		if (error)
1075 			break;
1076 	}
1077 
1078 out:
1079 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1080 	return (error);
1081 }
1082 
1083 static struct ioat_descriptor **
1084 ioat_prealloc_ring(struct ioat_softc *ioat, uint32_t size, boolean_t need_dscr,
1085     int mflags)
1086 {
1087 	struct ioat_descriptor **ring;
1088 	uint32_t i;
1089 	int error;
1090 
1091 	KASSERT(size > 0 && powerof2(size), ("bogus size"));
1092 
1093 	ring = malloc(size * sizeof(*ring), M_IOAT, M_ZERO | mflags);
1094 	if (ring == NULL)
1095 		return (NULL);
1096 
1097 	if (need_dscr) {
1098 		error = ENOMEM;
1099 		for (i = size / 2; i < size; i++) {
1100 			ring[i] = ioat_alloc_ring_entry(ioat, mflags);
1101 			if (ring[i] == NULL)
1102 				goto out;
1103 			ring[i]->id = i;
1104 		}
1105 	}
1106 	error = 0;
1107 
1108 out:
1109 	if (error != 0 && ring != NULL) {
1110 		ioat_free_ring(ioat, size, ring);
1111 		ring = NULL;
1112 	}
1113 	return (ring);
1114 }
1115 
1116 static void
1117 ioat_free_ring(struct ioat_softc *ioat, uint32_t size,
1118     struct ioat_descriptor **ring)
1119 {
1120 	uint32_t i;
1121 
1122 	for (i = 0; i < size; i++) {
1123 		if (ring[i] != NULL)
1124 			ioat_free_ring_entry(ioat, ring[i]);
1125 	}
1126 	free(ring, M_IOAT);
1127 }
1128 
1129 static struct ioat_descriptor *
1130 ioat_get_ring_entry(struct ioat_softc *ioat, uint32_t index)
1131 {
1132 
1133 	return (ioat->ring[index % (1 << ioat->ring_size_order)]);
1134 }
1135 
1136 static int
1137 ring_grow(struct ioat_softc *ioat, uint32_t oldorder,
1138     struct ioat_descriptor **newring)
1139 {
1140 	struct ioat_descriptor *tmp, *next;
1141 	struct ioat_dma_hw_descriptor *hw;
1142 	uint32_t oldsize, newsize, head, tail, i, end;
1143 	int error;
1144 
1145 	CTR0(KTR_IOAT, __func__);
1146 
1147 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1148 
1149 	if (oldorder != ioat->ring_size_order || oldorder >= IOAT_MAX_ORDER) {
1150 		error = EINVAL;
1151 		goto out;
1152 	}
1153 
1154 	oldsize = (1 << oldorder);
1155 	newsize = (1 << (oldorder + 1));
1156 
1157 	mtx_lock(&ioat->cleanup_lock);
1158 
1159 	head = ioat->head & (oldsize - 1);
1160 	tail = ioat->tail & (oldsize - 1);
1161 
1162 	/* Copy old descriptors to new ring */
1163 	for (i = 0; i < oldsize; i++)
1164 		newring[i] = ioat->ring[i];
1165 
1166 	/*
1167 	 * If head has wrapped but tail hasn't, we must swap some descriptors
1168 	 * around so that tail can increment directly to head.
1169 	 */
1170 	if (head < tail) {
1171 		for (i = 0; i <= head; i++) {
1172 			tmp = newring[oldsize + i];
1173 
1174 			newring[oldsize + i] = newring[i];
1175 			newring[oldsize + i]->id = oldsize + i;
1176 
1177 			newring[i] = tmp;
1178 			newring[i]->id = i;
1179 		}
1180 		head += oldsize;
1181 	}
1182 
1183 	KASSERT(head >= tail, ("invariants"));
1184 
1185 	/* Head didn't wrap; we only need to link in oldsize..newsize */
1186 	if (head < oldsize) {
1187 		i = oldsize - 1;
1188 		end = newsize;
1189 	} else {
1190 		/* Head did wrap; link newhead..newsize and 0..oldhead */
1191 		i = head;
1192 		end = newsize + (head - oldsize) + 1;
1193 	}
1194 
1195 	/*
1196 	 * Fix up hardware ring, being careful not to trample the active
1197 	 * section (tail -> head).
1198 	 */
1199 	for (; i < end; i++) {
1200 		KASSERT((i & (newsize - 1)) < tail ||
1201 		    (i & (newsize - 1)) >= head, ("trampling snake"));
1202 
1203 		next = newring[(i + 1) & (newsize - 1)];
1204 		hw = newring[i & (newsize - 1)]->u.dma;
1205 		hw->next = next->hw_desc_bus_addr;
1206 	}
1207 
1208 	free(ioat->ring, M_IOAT);
1209 	ioat->ring = newring;
1210 	ioat->ring_size_order = oldorder + 1;
1211 	ioat->tail = tail;
1212 	ioat->head = head;
1213 	error = 0;
1214 
1215 	mtx_unlock(&ioat->cleanup_lock);
1216 out:
1217 	if (error)
1218 		ioat_free_ring(ioat, (1 << (oldorder + 1)), newring);
1219 	return (error);
1220 }
1221 
1222 static int
1223 ring_shrink(struct ioat_softc *ioat, uint32_t oldorder,
1224     struct ioat_descriptor **newring)
1225 {
1226 	struct ioat_dma_hw_descriptor *hw;
1227 	struct ioat_descriptor *ent, *next;
1228 	uint32_t oldsize, newsize, current_idx, new_idx, i;
1229 	int error;
1230 
1231 	CTR0(KTR_IOAT, __func__);
1232 
1233 	mtx_assert(&ioat->submit_lock, MA_OWNED);
1234 
1235 	if (oldorder != ioat->ring_size_order || oldorder <= IOAT_MIN_ORDER) {
1236 		error = EINVAL;
1237 		goto out_unlocked;
1238 	}
1239 
1240 	oldsize = (1 << oldorder);
1241 	newsize = (1 << (oldorder - 1));
1242 
1243 	mtx_lock(&ioat->cleanup_lock);
1244 
1245 	/* Can't shrink below current active set! */
1246 	if (ioat_get_active(ioat) >= newsize) {
1247 		error = ENOMEM;
1248 		goto out;
1249 	}
1250 
1251 	/*
1252 	 * Copy current descriptors to the new ring, dropping the removed
1253 	 * descriptors.
1254 	 */
1255 	for (i = 0; i < newsize; i++) {
1256 		current_idx = (ioat->tail + i) & (oldsize - 1);
1257 		new_idx = (ioat->tail + i) & (newsize - 1);
1258 
1259 		newring[new_idx] = ioat->ring[current_idx];
1260 		newring[new_idx]->id = new_idx;
1261 	}
1262 
1263 	/* Free deleted descriptors */
1264 	for (i = newsize; i < oldsize; i++) {
1265 		ent = ioat_get_ring_entry(ioat, ioat->tail + i);
1266 		ioat_free_ring_entry(ioat, ent);
1267 	}
1268 
1269 	/* Fix up hardware ring. */
1270 	hw = newring[(ioat->tail + newsize - 1) & (newsize - 1)]->u.dma;
1271 	next = newring[(ioat->tail + newsize) & (newsize - 1)];
1272 	hw->next = next->hw_desc_bus_addr;
1273 
1274 	free(ioat->ring, M_IOAT);
1275 	ioat->ring = newring;
1276 	ioat->ring_size_order = oldorder - 1;
1277 	error = 0;
1278 
1279 out:
1280 	mtx_unlock(&ioat->cleanup_lock);
1281 out_unlocked:
1282 	if (error)
1283 		ioat_free_ring(ioat, (1 << (oldorder - 1)), newring);
1284 	return (error);
1285 }
1286 
1287 static void
1288 ioat_halted_debug(struct ioat_softc *ioat, uint32_t chanerr)
1289 {
1290 	struct ioat_descriptor *desc;
1291 
1292 	ioat_log_message(0, "Channel halted (%b)\n", (int)chanerr,
1293 	    IOAT_CHANERR_STR);
1294 	if (chanerr == 0)
1295 		return;
1296 
1297 	mtx_assert(&ioat->cleanup_lock, MA_OWNED);
1298 
1299 	desc = ioat_get_ring_entry(ioat, ioat->tail + 0);
1300 	dump_descriptor(desc->u.raw);
1301 
1302 	desc = ioat_get_ring_entry(ioat, ioat->tail + 1);
1303 	dump_descriptor(desc->u.raw);
1304 }
1305 
1306 static void
1307 ioat_timer_callback(void *arg)
1308 {
1309 	struct ioat_descriptor **newring;
1310 	struct ioat_softc *ioat;
1311 	uint32_t order;
1312 
1313 	ioat = arg;
1314 	ioat_log_message(1, "%s\n", __func__);
1315 
1316 	if (ioat->is_completion_pending) {
1317 		ioat_process_events(ioat);
1318 		return;
1319 	}
1320 
1321 	/* Slowly scale the ring down if idle. */
1322 	mtx_lock(&ioat->submit_lock);
1323 	order = ioat->ring_size_order;
1324 	if (ioat->is_resize_pending || order == IOAT_MIN_ORDER) {
1325 		mtx_unlock(&ioat->submit_lock);
1326 		goto out;
1327 	}
1328 	ioat->is_resize_pending = TRUE;
1329 	mtx_unlock(&ioat->submit_lock);
1330 
1331 	newring = ioat_prealloc_ring(ioat, 1 << (order - 1), FALSE,
1332 	    M_NOWAIT);
1333 
1334 	mtx_lock(&ioat->submit_lock);
1335 	KASSERT(ioat->ring_size_order == order,
1336 	    ("resize_pending protects order"));
1337 
1338 	if (newring != NULL)
1339 		ring_shrink(ioat, order, newring);
1340 
1341 	ioat->is_resize_pending = FALSE;
1342 	mtx_unlock(&ioat->submit_lock);
1343 
1344 out:
1345 	if (ioat->ring_size_order > IOAT_MIN_ORDER)
1346 		callout_reset(&ioat->timer, 10 * hz,
1347 		    ioat_timer_callback, ioat);
1348 }
1349 
1350 /*
1351  * Support Functions
1352  */
1353 static void
1354 ioat_submit_single(struct ioat_softc *ioat)
1355 {
1356 
1357 	ioat_get(ioat, IOAT_ACTIVE_DESCR_REF);
1358 	atomic_add_rel_int(&ioat->head, 1);
1359 	atomic_add_rel_int(&ioat->hw_head, 1);
1360 
1361 	if (!ioat->is_completion_pending) {
1362 		ioat->is_completion_pending = TRUE;
1363 		callout_reset(&ioat->timer, IOAT_INTR_TIMO,
1364 		    ioat_timer_callback, ioat);
1365 	}
1366 }
1367 
1368 static int
1369 ioat_reset_hw(struct ioat_softc *ioat)
1370 {
1371 	uint64_t status;
1372 	uint32_t chanerr;
1373 	unsigned timeout;
1374 	int error;
1375 
1376 	mtx_lock(IOAT_REFLK);
1377 	ioat->quiescing = TRUE;
1378 	ioat_drain_locked(ioat);
1379 	mtx_unlock(IOAT_REFLK);
1380 
1381 	status = ioat_get_chansts(ioat);
1382 	if (is_ioat_active(status) || is_ioat_idle(status))
1383 		ioat_suspend(ioat);
1384 
1385 	/* Wait at most 20 ms */
1386 	for (timeout = 0; (is_ioat_active(status) || is_ioat_idle(status)) &&
1387 	    timeout < 20; timeout++) {
1388 		DELAY(1000);
1389 		status = ioat_get_chansts(ioat);
1390 	}
1391 	if (timeout == 20) {
1392 		error = ETIMEDOUT;
1393 		goto out;
1394 	}
1395 
1396 	KASSERT(ioat_get_active(ioat) == 0, ("active after quiesce"));
1397 
1398 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
1399 	ioat_write_4(ioat, IOAT_CHANERR_OFFSET, chanerr);
1400 
1401 	/*
1402 	 * IOAT v3 workaround - CHANERRMSK_INT with 3E07h to masks out errors
1403 	 *  that can cause stability issues for IOAT v3.
1404 	 */
1405 	pci_write_config(ioat->device, IOAT_CFG_CHANERRMASK_INT_OFFSET, 0x3e07,
1406 	    4);
1407 	chanerr = pci_read_config(ioat->device, IOAT_CFG_CHANERR_INT_OFFSET, 4);
1408 	pci_write_config(ioat->device, IOAT_CFG_CHANERR_INT_OFFSET, chanerr, 4);
1409 
1410 	/*
1411 	 * BDXDE and BWD models reset MSI-X registers on device reset.
1412 	 * Save/restore their contents manually.
1413 	 */
1414 	if (ioat_model_resets_msix(ioat)) {
1415 		ioat_log_message(1, "device resets MSI-X registers; saving\n");
1416 		pci_save_state(ioat->device);
1417 	}
1418 
1419 	ioat_reset(ioat);
1420 
1421 	/* Wait at most 20 ms */
1422 	for (timeout = 0; ioat_reset_pending(ioat) && timeout < 20; timeout++)
1423 		DELAY(1000);
1424 	if (timeout == 20) {
1425 		error = ETIMEDOUT;
1426 		goto out;
1427 	}
1428 
1429 	if (ioat_model_resets_msix(ioat)) {
1430 		ioat_log_message(1, "device resets registers; restored\n");
1431 		pci_restore_state(ioat->device);
1432 	}
1433 
1434 	/* Reset attempts to return the hardware to "halted." */
1435 	status = ioat_get_chansts(ioat);
1436 	if (is_ioat_active(status) || is_ioat_idle(status)) {
1437 		/* So this really shouldn't happen... */
1438 		ioat_log_message(0, "Device is active after a reset?\n");
1439 		ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
1440 		error = 0;
1441 		goto out;
1442 	}
1443 
1444 	chanerr = ioat_read_4(ioat, IOAT_CHANERR_OFFSET);
1445 	if (chanerr != 0) {
1446 		mtx_lock(&ioat->cleanup_lock);
1447 		ioat_halted_debug(ioat, chanerr);
1448 		mtx_unlock(&ioat->cleanup_lock);
1449 		error = EIO;
1450 		goto out;
1451 	}
1452 
1453 	/*
1454 	 * Bring device back online after reset.  Writing CHAINADDR brings the
1455 	 * device back to active.
1456 	 *
1457 	 * The internal ring counter resets to zero, so we have to start over
1458 	 * at zero as well.
1459 	 */
1460 	ioat->tail = ioat->head = ioat->hw_head = 0;
1461 	ioat->last_seen = 0;
1462 
1463 	ioat_write_chanctrl(ioat, IOAT_CHANCTRL_RUN);
1464 	ioat_write_chancmp(ioat, ioat->comp_update_bus_addr);
1465 	ioat_write_chainaddr(ioat, ioat->ring[0]->hw_desc_bus_addr);
1466 	error = 0;
1467 
1468 out:
1469 	mtx_lock(IOAT_REFLK);
1470 	ioat->quiescing = FALSE;
1471 	mtx_unlock(IOAT_REFLK);
1472 
1473 	if (error == 0)
1474 		error = ioat_start_channel(ioat);
1475 
1476 	return (error);
1477 }
1478 
1479 static int
1480 sysctl_handle_chansts(SYSCTL_HANDLER_ARGS)
1481 {
1482 	struct ioat_softc *ioat;
1483 	struct sbuf sb;
1484 	uint64_t status;
1485 	int error;
1486 
1487 	ioat = arg1;
1488 
1489 	status = ioat_get_chansts(ioat) & IOAT_CHANSTS_STATUS;
1490 
1491 	sbuf_new_for_sysctl(&sb, NULL, 256, req);
1492 	switch (status) {
1493 	case IOAT_CHANSTS_ACTIVE:
1494 		sbuf_printf(&sb, "ACTIVE");
1495 		break;
1496 	case IOAT_CHANSTS_IDLE:
1497 		sbuf_printf(&sb, "IDLE");
1498 		break;
1499 	case IOAT_CHANSTS_SUSPENDED:
1500 		sbuf_printf(&sb, "SUSPENDED");
1501 		break;
1502 	case IOAT_CHANSTS_HALTED:
1503 		sbuf_printf(&sb, "HALTED");
1504 		break;
1505 	case IOAT_CHANSTS_ARMED:
1506 		sbuf_printf(&sb, "ARMED");
1507 		break;
1508 	default:
1509 		sbuf_printf(&sb, "UNKNOWN");
1510 		break;
1511 	}
1512 	error = sbuf_finish(&sb);
1513 	sbuf_delete(&sb);
1514 
1515 	if (error != 0 || req->newptr == NULL)
1516 		return (error);
1517 	return (EINVAL);
1518 }
1519 
1520 static int
1521 sysctl_handle_error(SYSCTL_HANDLER_ARGS)
1522 {
1523 	struct ioat_descriptor *desc;
1524 	struct ioat_softc *ioat;
1525 	int error, arg;
1526 
1527 	ioat = arg1;
1528 
1529 	arg = 0;
1530 	error = SYSCTL_OUT(req, &arg, sizeof(arg));
1531 	if (error != 0 || req->newptr == NULL)
1532 		return (error);
1533 
1534 	error = SYSCTL_IN(req, &arg, sizeof(arg));
1535 	if (error != 0)
1536 		return (error);
1537 
1538 	if (arg != 0) {
1539 		ioat_acquire(&ioat->dmaengine);
1540 		desc = ioat_op_generic(ioat, IOAT_OP_COPY, 1,
1541 		    0xffff000000000000ull, 0xffff000000000000ull, NULL, NULL,
1542 		    0);
1543 		if (desc == NULL)
1544 			error = ENOMEM;
1545 		else
1546 			ioat_submit_single(ioat);
1547 		ioat_release(&ioat->dmaengine);
1548 	}
1549 	return (error);
1550 }
1551 
1552 static int
1553 sysctl_handle_reset(SYSCTL_HANDLER_ARGS)
1554 {
1555 	struct ioat_softc *ioat;
1556 	int error, arg;
1557 
1558 	ioat = arg1;
1559 
1560 	arg = 0;
1561 	error = SYSCTL_OUT(req, &arg, sizeof(arg));
1562 	if (error != 0 || req->newptr == NULL)
1563 		return (error);
1564 
1565 	error = SYSCTL_IN(req, &arg, sizeof(arg));
1566 	if (error != 0)
1567 		return (error);
1568 
1569 	if (arg != 0)
1570 		error = ioat_reset_hw(ioat);
1571 
1572 	return (error);
1573 }
1574 
1575 static void
1576 dump_descriptor(void *hw_desc)
1577 {
1578 	int i, j;
1579 
1580 	for (i = 0; i < 2; i++) {
1581 		for (j = 0; j < 8; j++)
1582 			printf("%08x ", ((uint32_t *)hw_desc)[i * 8 + j]);
1583 		printf("\n");
1584 	}
1585 }
1586 
1587 static void
1588 ioat_setup_sysctl(device_t device)
1589 {
1590 	struct sysctl_oid_list *par;
1591 	struct sysctl_ctx_list *ctx;
1592 	struct sysctl_oid *tree;
1593 	struct ioat_softc *ioat;
1594 
1595 	ioat = DEVICE2SOFTC(device);
1596 	ctx = device_get_sysctl_ctx(device);
1597 	tree = device_get_sysctl_tree(device);
1598 	par = SYSCTL_CHILDREN(tree);
1599 
1600 	SYSCTL_ADD_INT(ctx, par, OID_AUTO, "version", CTLFLAG_RD,
1601 	    &ioat->version, 0, "HW version (0xMM form)");
1602 	SYSCTL_ADD_UINT(ctx, par, OID_AUTO, "max_xfer_size", CTLFLAG_RD,
1603 	    &ioat->max_xfer_size, 0, "HW maximum transfer size");
1604 
1605 	SYSCTL_ADD_UINT(ctx, par, OID_AUTO, "ring_size_order", CTLFLAG_RD,
1606 	    &ioat->ring_size_order, 0, "SW descriptor ring size order");
1607 	SYSCTL_ADD_UINT(ctx, par, OID_AUTO, "head", CTLFLAG_RD, &ioat->head, 0,
1608 	    "SW descriptor head pointer index");
1609 	SYSCTL_ADD_UINT(ctx, par, OID_AUTO, "tail", CTLFLAG_RD, &ioat->tail, 0,
1610 	    "SW descriptor tail pointer index");
1611 	SYSCTL_ADD_UINT(ctx, par, OID_AUTO, "hw_head", CTLFLAG_RD,
1612 	    &ioat->hw_head, 0, "HW DMACOUNT");
1613 
1614 	SYSCTL_ADD_UQUAD(ctx, par, OID_AUTO, "last_completion", CTLFLAG_RD,
1615 	    ioat->comp_update, "HW addr of last completion");
1616 
1617 	SYSCTL_ADD_INT(ctx, par, OID_AUTO, "is_resize_pending", CTLFLAG_RD,
1618 	    &ioat->is_resize_pending, 0, "resize pending");
1619 	SYSCTL_ADD_INT(ctx, par, OID_AUTO, "is_completion_pending", CTLFLAG_RD,
1620 	    &ioat->is_completion_pending, 0, "completion pending");
1621 	SYSCTL_ADD_INT(ctx, par, OID_AUTO, "is_reset_pending", CTLFLAG_RD,
1622 	    &ioat->is_reset_pending, 0, "reset pending");
1623 	SYSCTL_ADD_INT(ctx, par, OID_AUTO, "is_channel_running", CTLFLAG_RD,
1624 	    &ioat->is_channel_running, 0, "channel running");
1625 
1626 	SYSCTL_ADD_PROC(ctx, par, OID_AUTO, "force_hw_reset",
1627 	    CTLTYPE_INT | CTLFLAG_RW, ioat, 0, sysctl_handle_reset, "I",
1628 	    "Set to non-zero to reset the hardware");
1629 	SYSCTL_ADD_PROC(ctx, par, OID_AUTO, "force_hw_error",
1630 	    CTLTYPE_INT | CTLFLAG_RW, ioat, 0, sysctl_handle_error, "I",
1631 	    "Set to non-zero to inject a recoverable hardware error");
1632 	SYSCTL_ADD_PROC(ctx, par, OID_AUTO, "chansts",
1633 	    CTLTYPE_STRING | CTLFLAG_RD, ioat, 0, sysctl_handle_chansts, "A",
1634 	    "String of the channel status");
1635 }
1636 
1637 static inline struct ioat_softc *
1638 ioat_get(struct ioat_softc *ioat, enum ioat_ref_kind kind)
1639 {
1640 	uint32_t old;
1641 
1642 	KASSERT(kind < IOAT_NUM_REF_KINDS, ("bogus"));
1643 
1644 	old = atomic_fetchadd_32(&ioat->refcnt, 1);
1645 	KASSERT(old < UINT32_MAX, ("refcnt overflow"));
1646 
1647 #ifdef INVARIANTS
1648 	old = atomic_fetchadd_32(&ioat->refkinds[kind], 1);
1649 	KASSERT(old < UINT32_MAX, ("refcnt kind overflow"));
1650 #endif
1651 
1652 	return (ioat);
1653 }
1654 
1655 static inline void
1656 ioat_putn(struct ioat_softc *ioat, uint32_t n, enum ioat_ref_kind kind)
1657 {
1658 
1659 	_ioat_putn(ioat, n, kind, FALSE);
1660 }
1661 
1662 static inline void
1663 ioat_putn_locked(struct ioat_softc *ioat, uint32_t n, enum ioat_ref_kind kind)
1664 {
1665 
1666 	_ioat_putn(ioat, n, kind, TRUE);
1667 }
1668 
1669 static inline void
1670 _ioat_putn(struct ioat_softc *ioat, uint32_t n, enum ioat_ref_kind kind,
1671     boolean_t locked)
1672 {
1673 	uint32_t old;
1674 
1675 	KASSERT(kind < IOAT_NUM_REF_KINDS, ("bogus"));
1676 
1677 	if (n == 0)
1678 		return;
1679 
1680 #ifdef INVARIANTS
1681 	old = atomic_fetchadd_32(&ioat->refkinds[kind], -n);
1682 	KASSERT(old >= n, ("refcnt kind underflow"));
1683 #endif
1684 
1685 	/* Skip acquiring the lock if resulting refcnt > 0. */
1686 	for (;;) {
1687 		old = ioat->refcnt;
1688 		if (old <= n)
1689 			break;
1690 		if (atomic_cmpset_32(&ioat->refcnt, old, old - n))
1691 			return;
1692 	}
1693 
1694 	if (locked)
1695 		mtx_assert(IOAT_REFLK, MA_OWNED);
1696 	else
1697 		mtx_lock(IOAT_REFLK);
1698 
1699 	old = atomic_fetchadd_32(&ioat->refcnt, -n);
1700 	KASSERT(old >= n, ("refcnt error"));
1701 
1702 	if (old == n)
1703 		wakeup(IOAT_REFLK);
1704 	if (!locked)
1705 		mtx_unlock(IOAT_REFLK);
1706 }
1707 
1708 static inline void
1709 ioat_put(struct ioat_softc *ioat, enum ioat_ref_kind kind)
1710 {
1711 
1712 	ioat_putn(ioat, 1, kind);
1713 }
1714 
1715 static void
1716 ioat_drain_locked(struct ioat_softc *ioat)
1717 {
1718 
1719 	mtx_assert(IOAT_REFLK, MA_OWNED);
1720 	while (ioat->refcnt > 0)
1721 		msleep(IOAT_REFLK, IOAT_REFLK, 0, "ioat_drain", 0);
1722 }
1723