xref: /freebsd/sys/dev/thunderbolt/nhi.c (revision 561571d480679933287a6d21c6929c39a7963857)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2022 Scott Long
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include "opt_thunderbolt.h"
30 
31 /* PCIe interface for Thunderbolt Native Host Interface (nhi) */
32 #include <sys/types.h>
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/module.h>
37 #include <sys/bus.h>
38 #include <sys/conf.h>
39 #include <sys/malloc.h>
40 #include <sys/queue.h>
41 #include <sys/sysctl.h>
42 #include <sys/lock.h>
43 #include <sys/mutex.h>
44 #include <sys/taskqueue.h>
45 #include <sys/gsb_crc32.h>
46 #include <sys/endian.h>
47 #include <vm/vm.h>
48 #include <vm/pmap.h>
49 
50 #include <machine/bus.h>
51 #include <machine/stdarg.h>
52 
53 #include <dev/thunderbolt/nhi_reg.h>
54 #include <dev/thunderbolt/nhi_var.h>
55 #include <dev/thunderbolt/tb_reg.h>
56 #include <dev/thunderbolt/tb_var.h>
57 #include <dev/thunderbolt/tb_debug.h>
58 #include <dev/thunderbolt/hcm_var.h>
59 #include <dev/thunderbolt/tbcfg_reg.h>
60 #include <dev/thunderbolt/router_var.h>
61 #include <dev/thunderbolt/tb_dev.h>
62 #include "tb_if.h"
63 
64 static int nhi_alloc_ring(struct nhi_softc *, int, int, int,
65     struct nhi_ring_pair **);
66 static void nhi_free_ring(struct nhi_ring_pair *);
67 static void nhi_free_rings(struct nhi_softc *);
68 static int nhi_configure_ring(struct nhi_softc *, struct nhi_ring_pair *);
69 static int nhi_activate_ring(struct nhi_ring_pair *);
70 static int nhi_deactivate_ring(struct nhi_ring_pair *);
71 static int nhi_alloc_ring0(struct nhi_softc *);
72 static void nhi_free_ring0(struct nhi_softc *);
73 static void nhi_fill_rx_ring(struct nhi_softc *, struct nhi_ring_pair *);
74 static int nhi_init(struct nhi_softc *);
75 static void nhi_post_init(void *);
76 static int nhi_tx_enqueue(struct nhi_ring_pair *, struct nhi_cmd_frame *);
77 static int nhi_setup_sysctl(struct nhi_softc *);
78 
79 SYSCTL_NODE(_hw, OID_AUTO, nhi, CTLFLAG_RD, 0, "NHI Driver Parameters");
80 
81 MALLOC_DEFINE(M_NHI, "nhi", "nhi driver memory");
82 
83 #ifndef NHI_DEBUG_LEVEL
84 #define NHI_DEBUG_LEVEL 0
85 #endif
86 
87 /* 0 = default, 1 = force-on, 2 = force-off */
88 #ifndef NHI_FORCE_HCM
89 #define NHI_FORCE_HCM 0
90 #endif
91 
92 void
nhi_get_tunables(struct nhi_softc * sc)93 nhi_get_tunables(struct nhi_softc *sc)
94 {
95 	devclass_t dc;
96 	device_t ufp;
97 	char	tmpstr[80], oid[80];
98 	u_int	val;
99 
100 	/* Set local defaults */
101 	sc->debug = NHI_DEBUG_LEVEL;
102 	sc->max_ring_count = NHI_DEFAULT_NUM_RINGS;
103 	sc->force_hcm = NHI_FORCE_HCM;
104 
105 	/* Inherit setting from the upstream thunderbolt switch node */
106 	val = TB_GET_DEBUG(sc->dev, &sc->debug);
107 	if (val != 0) {
108 		dc = devclass_find("tbolt");
109 		if (dc != NULL) {
110 			ufp = devclass_get_device(dc, device_get_unit(sc->dev));
111 			if (ufp != NULL)
112 				TB_GET_DEBUG(ufp, &sc->debug);
113 		} else {
114 			if (TUNABLE_STR_FETCH("hw.tbolt.debug_level", oid,
115 			    80) != 0)
116 				tb_parse_debug(&sc->debug, oid);
117 		}
118 	}
119 
120 	/*
121 	 * Grab global variables.  Allow nhi debug flags to override
122 	 * thunderbolt debug flags, if present.
123 	 */
124 	bzero(oid, 80);
125 	if (TUNABLE_STR_FETCH("hw.nhi.debug_level", oid, 80) != 0)
126 		tb_parse_debug(&sc->debug, oid);
127 	if (TUNABLE_INT_FETCH("hw.nhi.max_rings", &val) != 0) {
128 		val = min(val, NHI_MAX_NUM_RINGS);
129 		sc->max_ring_count = max(val, 1);
130 	}
131 	if (TUNABLE_INT_FETCH("hw.nhi.force_hcm", &val) != 0)
132 		sc->force_hcm = val;
133 
134 	/* Grab instance variables */
135 	bzero(oid, 80);
136 	snprintf(tmpstr, sizeof(tmpstr), "dev.nhi.%d.debug_level",
137 	    device_get_unit(sc->dev));
138 	if (TUNABLE_STR_FETCH(tmpstr, oid, 80) != 0)
139 		tb_parse_debug(&sc->debug, oid);
140 	snprintf(tmpstr, sizeof(tmpstr), "dev.nhi.%d.max_rings",
141 	    device_get_unit(sc->dev));
142 	if (TUNABLE_INT_FETCH(tmpstr, &val) != 0) {
143 		val = min(val, NHI_MAX_NUM_RINGS);
144 		sc->max_ring_count = max(val, 1);
145 	}
146 	snprintf(tmpstr, sizeof(tmpstr), "dev, nhi.%d.force_hcm",
147 	    device_get_unit(sc->dev));
148 	if (TUNABLE_INT_FETCH(tmpstr, &val) != 0)
149 		sc->force_hcm = val;
150 
151 	return;
152 }
153 
154 static void
nhi_configure_caps(struct nhi_softc * sc)155 nhi_configure_caps(struct nhi_softc *sc)
156 {
157 
158 	if (NHI_IS_USB4(sc) || (sc->force_hcm == NHI_FORCE_HCM_ON))
159 		sc->caps |= NHI_CAP_HCM;
160 	if (sc->force_hcm == NHI_FORCE_HCM_OFF)
161 		sc->caps &= ~NHI_CAP_HCM;
162 }
163 
164 struct nhi_cmd_frame *
nhi_alloc_tx_frame(struct nhi_ring_pair * r)165 nhi_alloc_tx_frame(struct nhi_ring_pair *r)
166 {
167 	struct nhi_cmd_frame *cmd;
168 
169 	mtx_lock(&r->mtx);
170 	cmd = nhi_alloc_tx_frame_locked(r);
171 	mtx_unlock(&r->mtx);
172 
173 	return (cmd);
174 }
175 
176 void
nhi_free_tx_frame(struct nhi_ring_pair * r,struct nhi_cmd_frame * cmd)177 nhi_free_tx_frame(struct nhi_ring_pair *r, struct nhi_cmd_frame *cmd)
178 {
179 	mtx_lock(&r->mtx);
180 	nhi_free_tx_frame_locked(r, cmd);
181 	mtx_unlock(&r->mtx);
182 }
183 
184 /*
185  * Push a command and data dword through the mailbox to the firmware.
186  * Response is either good, error, or timeout.  Commands that return data
187  * do so by reading OUTMAILDATA.
188  */
189 int
nhi_inmail_cmd(struct nhi_softc * sc,uint32_t cmd,uint32_t data)190 nhi_inmail_cmd(struct nhi_softc *sc, uint32_t cmd, uint32_t data)
191 {
192 	uint32_t val;
193 	u_int error, timeout;
194 
195 	mtx_lock(&sc->nhi_mtx);
196 	/*
197 	 * XXX Should a defer/reschedule happen here, or is it not worth
198 	 * worrying about?
199 	 */
200 	if (sc->hwflags & NHI_MBOX_BUSY) {
201 		mtx_unlock(&sc->nhi_mtx);
202 		tb_debug(sc, DBG_MBOX, "Driver busy with mailbox\n");
203 		return (EBUSY);
204 	}
205 	sc->hwflags |= NHI_MBOX_BUSY;
206 
207 	val = nhi_read_reg(sc, TBT_INMAILCMD);
208 	tb_debug(sc, DBG_MBOX|DBG_FULL, "Reading INMAILCMD= 0x%08x\n", val);
209 	if (val & INMAILCMD_ERROR)
210 		tb_debug(sc, DBG_MBOX, "Error already set in INMAILCMD\n");
211 	if (val & INMAILCMD_OPREQ) {
212 		mtx_unlock(&sc->nhi_mtx);
213 		tb_debug(sc, DBG_MBOX,
214 		    "INMAILCMD request already in progress\n");
215 		return (EBUSY);
216 	}
217 
218 	nhi_write_reg(sc, TBT_INMAILDATA, data);
219 	nhi_write_reg(sc, TBT_INMAILCMD, cmd | INMAILCMD_OPREQ);
220 
221 	/* Poll at 1s intervals */
222 	timeout = NHI_MAILBOX_TIMEOUT;
223 	while (timeout--) {
224 		DELAY(1000000);
225 		val = nhi_read_reg(sc, TBT_INMAILCMD);
226 		tb_debug(sc, DBG_MBOX|DBG_EXTRA,
227 		    "Polling INMAILCMD= 0x%08x\n", val);
228 		if ((val & INMAILCMD_OPREQ) == 0)
229 			break;
230 	}
231 	sc->hwflags &= ~NHI_MBOX_BUSY;
232 	mtx_unlock(&sc->nhi_mtx);
233 
234 	error = 0;
235 	if (val & INMAILCMD_OPREQ) {
236 		tb_printf(sc, "Timeout waiting for mailbox\n");
237 		error = ETIMEDOUT;
238 	}
239 	if (val & INMAILCMD_ERROR) {
240 		tb_printf(sc, "Firmware reports error in mailbox\n");
241 		error = EINVAL;
242 	}
243 
244 	return (error);
245 }
246 
247 /*
248  * Pull command status and data from the firmware mailbox.
249  */
250 int
nhi_outmail_cmd(struct nhi_softc * sc,uint32_t * val)251 nhi_outmail_cmd(struct nhi_softc *sc, uint32_t *val)
252 {
253 
254 	if (val == NULL)
255 		return (EINVAL);
256 	*val = nhi_read_reg(sc, TBT_OUTMAILCMD);
257 	return (0);
258 }
259 
260 int
nhi_attach(struct nhi_softc * sc)261 nhi_attach(struct nhi_softc *sc)
262 {
263 	uint32_t val;
264 	int error = 0;
265 
266 	if ((error = nhi_setup_sysctl(sc)) != 0)
267 		return (error);
268 
269 	mtx_init(&sc->nhi_mtx, "nhimtx", "NHI Control Mutex", MTX_DEF);
270 
271 	nhi_configure_caps(sc);
272 
273 	/*
274 	 * Get the number of TX/RX paths.  This sizes some of the register
275 	 * arrays during allocation and initialization.  USB4 spec says that
276 	 * the max is 21.  Alpine Ridge appears to default to 12.
277 	 */
278 	val = GET_HOST_CAPS_PATHS(nhi_read_reg(sc, NHI_HOST_CAPS));
279 	tb_debug(sc, DBG_INIT|DBG_NOISY, "Total Paths= %d\n", val);
280 	if ((val == 0) || (val > 21) || ((NHI_IS_AR(sc) && val != 12))) {
281 		tb_printf(sc, "WARN: unexpected number of paths: %d\n", val);
282 		/* return (ENXIO); */
283 	}
284 	sc->path_count = val;
285 
286 	SLIST_INIT(&sc->ring_list);
287 
288 	error = nhi_pci_configure_interrupts(sc);
289 	if (error == 0)
290 		error = nhi_alloc_ring0(sc);
291 	if (error == 0) {
292 		nhi_configure_ring(sc, sc->ring0);
293 		nhi_activate_ring(sc->ring0);
294 		nhi_fill_rx_ring(sc, sc->ring0);
295 	}
296 
297 	if (error == 0)
298 		error = tbdev_add_interface(sc);
299 
300 	if ((error == 0) && (NHI_USE_ICM(sc)))
301 		tb_printf(sc, "WARN: device uses an internal connection manager\n");
302 	if ((error == 0) && (NHI_USE_HCM(sc)))
303 		;
304 	error = hcm_attach(sc);
305 
306 	if (error == 0)
307 		error = nhi_init(sc);
308 
309 	return (error);
310 }
311 
312 int
nhi_detach(struct nhi_softc * sc)313 nhi_detach(struct nhi_softc *sc)
314 {
315 
316 	if (NHI_USE_HCM(sc))
317 		hcm_detach(sc);
318 
319 	if (sc->root_rsc != NULL)
320 		tb_router_detach(sc->root_rsc);
321 
322 	tbdev_remove_interface(sc);
323 
324 	nhi_pci_disable_interrupts(sc);
325 	nhi_pci_free_interrupts(sc);
326 
327 	nhi_free_ring0(sc);
328 
329 	/* XXX Should the rings be marked as !VALID in the descriptors? */
330 	nhi_free_rings(sc);
331 
332 	mtx_destroy(&sc->nhi_mtx);
333 
334 	return (0);
335 }
336 
337 static void
nhi_memaddr_cb(void * arg,bus_dma_segment_t * segs,int nsegs,int error)338 nhi_memaddr_cb(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
339 {
340 	bus_addr_t *addr;
341 
342 	addr = arg;
343 	if (error == 0 && nsegs == 1) {
344 		*addr = segs[0].ds_addr;
345 	} else
346 		*addr = 0;
347 }
348 
349 static int
nhi_alloc_ring(struct nhi_softc * sc,int ringnum,int tx_depth,int rx_depth,struct nhi_ring_pair ** rp)350 nhi_alloc_ring(struct nhi_softc *sc, int ringnum, int tx_depth, int rx_depth,
351     struct nhi_ring_pair **rp)
352 {
353 	bus_dma_template_t t;
354 	bus_addr_t ring_busaddr;
355 	struct nhi_ring_pair *r;
356 	int ring_size, error;
357 	u_int rxring_len, txring_len;
358 	char *ring;
359 
360 	if (ringnum >= sc->max_ring_count) {
361 		tb_debug(sc, DBG_INIT, "Tried to allocate ring number %d\n",
362 		    ringnum);
363 		return (EINVAL);
364 	}
365 
366 	/* Allocate the ring structure and the RX ring tacker together. */
367 	rxring_len = rx_depth * sizeof(void *);
368 	txring_len = tx_depth * sizeof(void *);
369 	r = malloc(sizeof(struct nhi_ring_pair) + rxring_len + txring_len,
370 	    M_NHI, M_NOWAIT|M_ZERO);
371 	if (r == NULL) {
372 		tb_printf(sc, "ERROR: Cannot allocate ring memory\n");
373 		return (ENOMEM);
374 	}
375 
376 	r->sc = sc;
377 	TAILQ_INIT(&r->tx_head);
378 	TAILQ_INIT(&r->rx_head);
379 	r->ring_num = ringnum;
380 	r->tx_ring_depth = tx_depth;
381 	r->tx_ring_mask = tx_depth - 1;
382 	r->rx_ring_depth = rx_depth;
383 	r->rx_ring_mask = rx_depth - 1;
384 	r->rx_pici_reg = NHI_RX_RING_PICI + ringnum * 16;
385 	r->tx_pici_reg = NHI_TX_RING_PICI + ringnum * 16;
386 	r->rx_cmd_ring = (struct nhi_cmd_frame **)((uint8_t *)r + sizeof (*r));
387 	r->tx_cmd_ring = (struct nhi_cmd_frame **)((uint8_t *)r->rx_cmd_ring +
388 	    rxring_len);
389 
390 	snprintf(r->name, NHI_RING_NAMELEN, "nhiring%d\n", ringnum);
391 	mtx_init(&r->mtx, r->name, "NHI Ring Lock", MTX_DEF);
392 	tb_debug(sc, DBG_INIT | DBG_FULL, "Allocated ring context at %p, "
393 	    "mutex %p\n", r, &r->mtx);
394 
395 	/* Allocate the RX and TX buffer descriptor rings */
396 	ring_size = sizeof(struct nhi_tx_buffer_desc) * r->tx_ring_depth;
397 	ring_size += sizeof(struct nhi_rx_buffer_desc) * r->rx_ring_depth;
398 	tb_debug(sc, DBG_INIT | DBG_FULL, "Ring %d ring_size= %d\n",
399 	    ringnum, ring_size);
400 
401 	bus_dma_template_init(&t, sc->parent_dmat);
402 	t.alignment = 4;
403 	t.maxsize = t.maxsegsize = ring_size;
404 	t.nsegments = 1;
405 	if ((error = bus_dma_template_tag(&t, &r->ring_dmat)) != 0) {
406 		tb_printf(sc, "Cannot allocate ring %d DMA tag: %d\n",
407 		    ringnum, error);
408 		return (ENOMEM);
409 	}
410 	if (bus_dmamem_alloc(r->ring_dmat, (void **)&ring, BUS_DMA_NOWAIT,
411 	    &r->ring_map)) {
412 		tb_printf(sc, "Cannot allocate ring memory\n");
413 		return (ENOMEM);
414 	}
415 	bzero(ring, ring_size);
416 	bus_dmamap_load(r->ring_dmat, r->ring_map, ring, ring_size,
417 	    nhi_memaddr_cb, &ring_busaddr, 0);
418 
419 	r->ring = ring;
420 
421 	r->tx_ring = (union nhi_ring_desc *)(ring);
422 	r->tx_ring_busaddr = ring_busaddr;
423 	ring += sizeof(struct nhi_tx_buffer_desc) * r->tx_ring_depth;
424 	ring_busaddr += sizeof(struct nhi_tx_buffer_desc) * r->tx_ring_depth;
425 
426 	r->rx_ring = (union nhi_ring_desc *)(ring);
427 	r->rx_ring_busaddr = ring_busaddr;
428 
429 	tb_debug(sc, DBG_INIT | DBG_EXTRA, "Ring %d: RX %p [0x%jx] "
430 	    "TX %p [0x%jx]\n", ringnum, r->tx_ring, r->tx_ring_busaddr,
431 	    r->rx_ring, r->rx_ring_busaddr);
432 
433 	*rp = r;
434 	return (0);
435 }
436 
437 static void
nhi_free_ring(struct nhi_ring_pair * r)438 nhi_free_ring(struct nhi_ring_pair *r)
439 {
440 
441 	tb_debug(r->sc, DBG_INIT, "Freeing ring %d resources\n", r->ring_num);
442 	nhi_deactivate_ring(r);
443 
444 	if (r->tx_ring_busaddr != 0) {
445 		bus_dmamap_unload(r->ring_dmat, r->ring_map);
446 		r->tx_ring_busaddr = 0;
447 	}
448 	if (r->ring != NULL) {
449 		bus_dmamem_free(r->ring_dmat, r->ring, r->ring_map);
450 		r->ring = NULL;
451 	}
452 	if (r->ring_dmat != NULL) {
453 		bus_dma_tag_destroy(r->ring_dmat);
454 		r->ring_dmat = NULL;
455 	}
456 	mtx_destroy(&r->mtx);
457 }
458 
459 static void
nhi_free_rings(struct nhi_softc * sc)460 nhi_free_rings(struct nhi_softc *sc)
461 {
462 	struct nhi_ring_pair *r;
463 
464 	while ((r = SLIST_FIRST(&sc->ring_list)) != NULL) {
465 		nhi_free_ring(r);
466 		mtx_lock(&sc->nhi_mtx);
467 		SLIST_REMOVE_HEAD(&sc->ring_list, ring_link);
468 		mtx_unlock(&sc->nhi_mtx);
469 		free(r, M_NHI);
470 	}
471 
472 	return;
473 }
474 
475 static int
nhi_configure_ring(struct nhi_softc * sc,struct nhi_ring_pair * ring)476 nhi_configure_ring(struct nhi_softc *sc, struct nhi_ring_pair *ring)
477 {
478 	bus_addr_t busaddr;
479 	uint32_t val;
480 	int idx;
481 
482 	idx = ring->ring_num * 16;
483 
484 	/* Program the TX ring address and size */
485 	busaddr = ring->tx_ring_busaddr;
486 	nhi_write_reg(sc, NHI_TX_RING_ADDR_LO + idx, busaddr & 0xffffffff);
487 	nhi_write_reg(sc, NHI_TX_RING_ADDR_HI + idx, busaddr >> 32);
488 	nhi_write_reg(sc, NHI_TX_RING_SIZE + idx, ring->tx_ring_depth);
489 	nhi_write_reg(sc, NHI_TX_RING_TABLE_TIMESTAMP + idx, 0x0);
490 	tb_debug(sc, DBG_INIT, "TX Ring %d TX_RING_SIZE= 0x%x\n",
491 	    ring->ring_num, ring->tx_ring_depth);
492 
493 	/* Program the RX ring address and size */
494 	busaddr = ring->rx_ring_busaddr;
495 	val = (ring->rx_buffer_size << 16) | ring->rx_ring_depth;
496 	nhi_write_reg(sc, NHI_RX_RING_ADDR_LO + idx, busaddr & 0xffffffff);
497 	nhi_write_reg(sc, NHI_RX_RING_ADDR_HI + idx, busaddr >> 32);
498 	nhi_write_reg(sc, NHI_RX_RING_SIZE + idx, val);
499 	nhi_write_reg(sc, NHI_RX_RING_TABLE_BASE1 + idx, 0xffffffff);
500 	tb_debug(sc, DBG_INIT, "RX Ring %d RX_RING_SIZE= 0x%x\n",
501 	    ring->ring_num, val);
502 
503 	return (0);
504 }
505 
506 static int
nhi_activate_ring(struct nhi_ring_pair * ring)507 nhi_activate_ring(struct nhi_ring_pair *ring)
508 {
509 	struct nhi_softc *sc = ring->sc;
510 	int idx;
511 
512 	nhi_pci_enable_interrupt(ring);
513 
514 	idx = ring->ring_num * 32;
515 	tb_debug(sc, DBG_INIT, "Activating ring %d at idx %d\n",
516 	    ring->ring_num, idx);
517 	nhi_write_reg(sc, NHI_TX_RING_TABLE_BASE0 + idx,
518 	    TX_TABLE_RAW | TX_TABLE_VALID);
519 	nhi_write_reg(sc, NHI_RX_RING_TABLE_BASE0 + idx,
520 	    RX_TABLE_RAW | RX_TABLE_VALID);
521 
522 	return (0);
523 }
524 
525 static int
nhi_deactivate_ring(struct nhi_ring_pair * r)526 nhi_deactivate_ring(struct nhi_ring_pair *r)
527 {
528 	struct nhi_softc *sc = r->sc;
529 	int idx;
530 
531 	idx = r->ring_num * 32;
532 	tb_debug(sc, DBG_INIT, "Deactiving ring %d at idx %d\n",
533 	    r->ring_num, idx);
534 	nhi_write_reg(sc, NHI_TX_RING_TABLE_BASE0 + idx, 0);
535 	nhi_write_reg(sc, NHI_RX_RING_TABLE_BASE0 + idx, 0);
536 
537 	idx = r->ring_num * 16;
538 	tb_debug(sc, DBG_INIT, "Setting ring %d sizes to 0\n", r->ring_num);
539 	nhi_write_reg(sc, NHI_TX_RING_SIZE + idx, 0);
540 	nhi_write_reg(sc, NHI_RX_RING_SIZE + idx, 0);
541 
542 	return (0);
543 }
544 
545 static int
nhi_alloc_ring0(struct nhi_softc * sc)546 nhi_alloc_ring0(struct nhi_softc *sc)
547 {
548 	bus_addr_t frames_busaddr;
549 	bus_dma_template_t t;
550 	struct nhi_intr_tracker *trkr;
551 	struct nhi_ring_pair *r;
552 	struct nhi_cmd_frame *cmd;
553 	char *frames;
554 	int error, size, i;
555 
556 	if ((error = nhi_alloc_ring(sc, 0, NHI_RING0_TX_DEPTH,
557 	    NHI_RING0_RX_DEPTH, &r)) != 0) {
558 		tb_printf(sc, "Error allocating control ring\n");
559 		return (error);
560 	}
561 
562 	r->rx_buffer_size = NHI_RING0_FRAME_SIZE;/* Control packets are small */
563 
564 	/* Allocate the RX and TX buffers that are used for Ring0 comms */
565 	size = r->tx_ring_depth * NHI_RING0_FRAME_SIZE;
566 	size += r->rx_ring_depth * NHI_RING0_FRAME_SIZE;
567 
568 	bus_dma_template_init(&t, sc->parent_dmat);
569 	t.maxsize = t.maxsegsize = size;
570 	t.nsegments = 1;
571 	if (bus_dma_template_tag(&t, &sc->ring0_dmat)) {
572 		tb_printf(sc, "Error allocating control ring buffer tag\n");
573 		return (ENOMEM);
574 	}
575 
576 	if (bus_dmamem_alloc(sc->ring0_dmat, (void **)&frames, BUS_DMA_NOWAIT,
577 	    &sc->ring0_map) != 0) {
578 		tb_printf(sc, "Error allocating control ring memory\n");
579 		return (ENOMEM);
580 	}
581 	bzero(frames, size);
582 	bus_dmamap_load(sc->ring0_dmat, sc->ring0_map, frames, size,
583 	    nhi_memaddr_cb, &frames_busaddr, 0);
584 	sc->ring0_frames_busaddr = frames_busaddr;
585 	sc->ring0_frames = frames;
586 
587 	/* Allocate the driver command trackers */
588 	sc->ring0_cmds = malloc(sizeof(struct nhi_cmd_frame) *
589 	    (r->tx_ring_depth + r->rx_ring_depth), M_NHI, M_NOWAIT | M_ZERO);
590 	if (sc->ring0_cmds == NULL)
591 		return (ENOMEM);
592 
593 	/* Initialize the RX frames so they can be used */
594 	mtx_lock(&r->mtx);
595 	for (i = 0; i < r->rx_ring_depth; i++) {
596 		cmd = &sc->ring0_cmds[i];
597 		cmd->data = (uint32_t *)(frames + NHI_RING0_FRAME_SIZE * i);
598 		cmd->data_busaddr = frames_busaddr + NHI_RING0_FRAME_SIZE * i;
599 		cmd->flags = CMD_MAPPED;
600 		cmd->idx = i;
601 		TAILQ_INSERT_TAIL(&r->rx_head, cmd, cm_link);
602 	}
603 
604 	/* Inititalize the TX frames */
605 	for ( ; i < r->tx_ring_depth + r->rx_ring_depth - 1; i++) {
606 		cmd = &sc->ring0_cmds[i];
607 		cmd->data = (uint32_t *)(frames + NHI_RING0_FRAME_SIZE * i);
608 		cmd->data_busaddr = frames_busaddr + NHI_RING0_FRAME_SIZE * i;
609 		cmd->flags = CMD_MAPPED;
610 		cmd->idx = i;
611 		nhi_free_tx_frame_locked(r, cmd);
612 	}
613 	mtx_unlock(&r->mtx);
614 
615 	/* Do a 1:1 mapping of rings to interrupt vectors. */
616 	/* XXX Should be abstracted */
617 	trkr = &sc->intr_trackers[0];
618 	trkr->ring = r;
619 	r->tracker = trkr;
620 
621 	/* XXX Should be an array */
622 	sc->ring0 = r;
623 	SLIST_INSERT_HEAD(&sc->ring_list, r, ring_link);
624 
625 	return (0);
626 }
627 
628 static void
nhi_free_ring0(struct nhi_softc * sc)629 nhi_free_ring0(struct nhi_softc *sc)
630 {
631 	if (sc->ring0_cmds != NULL) {
632 		free(sc->ring0_cmds, M_NHI);
633 		sc->ring0_cmds = NULL;
634 	}
635 
636 	if (sc->ring0_frames_busaddr != 0) {
637 		bus_dmamap_unload(sc->ring0_dmat, sc->ring0_map);
638 		sc->ring0_frames_busaddr = 0;
639 	}
640 
641 	if (sc->ring0_frames != NULL) {
642 		bus_dmamem_free(sc->ring0_dmat, sc->ring0_frames,
643 		    sc->ring0_map);
644 		sc->ring0_frames = NULL;
645 	}
646 
647 	if (sc->ring0_dmat != NULL)
648 		bus_dma_tag_destroy(sc->ring0_dmat);
649 
650 	return;
651 }
652 
653 static void
nhi_fill_rx_ring(struct nhi_softc * sc,struct nhi_ring_pair * rp)654 nhi_fill_rx_ring(struct nhi_softc *sc, struct nhi_ring_pair *rp)
655 {
656 	struct nhi_cmd_frame *cmd;
657 	struct nhi_rx_buffer_desc *desc;
658 	u_int ci;
659 
660 	/* Assume that we never grow or shrink the ring population */
661 	rp->rx_ci = ci = 0;
662 	rp->rx_pi = 0;
663 
664 	do {
665 		cmd = TAILQ_FIRST(&rp->rx_head);
666 		if (cmd == NULL)
667 			break;
668 		TAILQ_REMOVE(&rp->rx_head, cmd, cm_link);
669 		desc = &rp->rx_ring[ci].rx;
670 		if ((cmd->flags & CMD_MAPPED) == 0)
671 			panic("Need rx buffer mapping code");
672 
673 		desc->addr_lo = cmd->data_busaddr & 0xffffffff;
674 		desc->addr_hi = (cmd->data_busaddr >> 32) & 0xffffffff;
675 		desc->offset = 0;
676 		desc->flags = RX_BUFFER_DESC_RS | RX_BUFFER_DESC_IE;
677 		rp->rx_ci = ci;
678 		rp->rx_cmd_ring[ci] = cmd;
679 		tb_debug(sc, DBG_RXQ | DBG_FULL,
680 		    "Updating ring%d ci= %d cmd= %p, busaddr= 0x%jx\n",
681 		    rp->ring_num, ci, cmd, cmd->data_busaddr);
682 
683 		ci = (rp->rx_ci + 1) & rp->rx_ring_mask;
684 	} while (ci != rp->rx_pi);
685 
686 	/* Update the CI in one shot */
687 	tb_debug(sc, DBG_RXQ, "Writing RX CI= %d\n", rp->rx_ci);
688 	nhi_write_reg(sc, rp->rx_pici_reg, rp->rx_ci);
689 
690 	return;
691 }
692 
693 static int
nhi_init(struct nhi_softc * sc)694 nhi_init(struct nhi_softc *sc)
695 {
696 	tb_route_t root_route = {0x0, 0x0};
697 	uint32_t val;
698 	int error;
699 
700 	tb_debug(sc, DBG_INIT, "Initializing NHI\n");
701 
702 	/* Set interrupt Auto-ACK */
703 	val = nhi_read_reg(sc, NHI_DMA_MISC);
704 	tb_debug(sc, DBG_INIT|DBG_FULL, "Read NHI_DMA_MISC= 0x%08x\n", val);
705 	val |= DMA_MISC_INT_AUTOCLEAR;
706 	tb_debug(sc, DBG_INIT, "Setting interrupt auto-ACK, 0x%08x\n", val);
707 	nhi_write_reg(sc, NHI_DMA_MISC, val);
708 
709 	if (NHI_IS_AR(sc) || NHI_IS_TR(sc) || NHI_IS_ICL(sc))
710 		tb_printf(sc, "WARN: device uses an internal connection manager\n");
711 
712 	/*
713 	 * Populate the controller (local) UUID, necessary for cross-domain
714 	 * communications.
715 	if (NHI_IS_ICL(sc))
716 		nhi_pci_get_uuid(sc);
717 	 */
718 
719 	/*
720 	 * Attach the router to the root thunderbolt bridge now that the DMA
721 	 * channel is configured and ready.
722 	 * The root router always has a route of 0x0...0, so set it statically
723 	 * here.
724 	 */
725 	if ((error = tb_router_attach_root(sc, root_route)) != 0)
726 		tb_printf(sc, "tb_router_attach_root()  error."
727 		    "  The driver should be loaded at boot\n");
728 
729 	if (error == 0) {
730 		sc->ich.ich_func = nhi_post_init;
731 		sc->ich.ich_arg = sc;
732 		error = config_intrhook_establish(&sc->ich);
733 		if (error)
734 			tb_printf(sc, "Failed to establish config hook\n");
735 	}
736 
737 	return (error);
738 }
739 
740 static void
nhi_post_init(void * arg)741 nhi_post_init(void *arg)
742 {
743 	struct nhi_softc *sc;
744 	uint8_t *u;
745 	int error;
746 
747 	sc = (struct nhi_softc *)arg;
748 	tb_debug(sc, DBG_INIT | DBG_EXTRA, "nhi_post_init\n");
749 
750 	bzero(sc->lc_uuid, 16);
751 	error = tb_config_get_lc_uuid(sc->root_rsc, sc->lc_uuid);
752 	if (error == 0) {
753 		u = sc->lc_uuid;
754 		tb_printf(sc, "Root Router LC UUID: %02x%02x%02x%02x-"
755 		    "%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x\n",
756 		    u[15], u[14], u[13], u[12], u[11], u[10], u[9], u[8], u[7],
757 		    u[6], u[5], u[4], u[3], u[2], u[1], u[0]);
758 	} else
759 		tb_printf(sc, "Error finding LC registers: %d\n", error);
760 
761 	u = sc->uuid;
762 	tb_printf(sc, "Root Router UUID: %02x%02x%02x%02x-"
763 	    "%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x\n",
764 	    u[15], u[14], u[13], u[12], u[11], u[10], u[9], u[8], u[7],
765 	    u[6], u[5], u[4], u[3], u[2], u[1], u[0]);
766 
767 	config_intrhook_disestablish(&sc->ich);
768 }
769 
770 static int
nhi_tx_enqueue(struct nhi_ring_pair * r,struct nhi_cmd_frame * cmd)771 nhi_tx_enqueue(struct nhi_ring_pair *r, struct nhi_cmd_frame *cmd)
772 {
773 	struct nhi_softc *sc;
774 	struct nhi_tx_buffer_desc *desc;
775 	uint16_t pi;
776 
777 	sc = r->sc;
778 
779 	/* A length of 0 means 4096.  Can't have longer lengths */
780 	if (cmd->req_len > TX_BUFFER_DESC_LEN_MASK + 1) {
781 		tb_debug(sc, DBG_TXQ, "Error: TX frame too big\n");
782 		return (EINVAL);
783 	}
784 	cmd->req_len &= TX_BUFFER_DESC_LEN_MASK;
785 
786 	mtx_lock(&r->mtx);
787 	desc = &r->tx_ring[r->tx_pi].tx;
788 	pi = (r->tx_pi + 1) & r->tx_ring_mask;
789 	if (pi == r->tx_ci) {
790 		mtx_unlock(&r->mtx);
791 		return (EBUSY);
792 	}
793 	r->tx_cmd_ring[r->tx_pi] = cmd;
794 	r->tx_pi = pi;
795 
796 	desc->addr_lo = htole32(cmd->data_busaddr & 0xffffffff);
797 	desc->addr_hi = htole32(cmd->data_busaddr >> 32);
798 	desc->eof_len = htole16((cmd->pdf << TX_BUFFER_DESC_EOF_SHIFT) |
799 	    cmd->req_len);
800 	desc->flags_sof = cmd->pdf | TX_BUFFER_DESC_IE | TX_BUFFER_DESC_RS;
801 	desc->offset = 0;
802 	desc->payload_time = 0;
803 
804 	tb_debug(sc, DBG_TXQ, "enqueue TXdescIdx= %d cmdidx= %d len= %d, "
805 	    "busaddr= 0x%jx\n", r->tx_pi, cmd->idx, cmd->req_len,
806 	    cmd->data_busaddr);
807 
808 	nhi_write_reg(sc, r->tx_pici_reg, pi << TX_RING_PI_SHIFT | r->tx_ci);
809 	mtx_unlock(&r->mtx);
810 	return (0);
811 }
812 
813 /*
814  * No scheduling happens for now.  Ring0 scheduling is done in the TB
815  * layer.
816  */
817 int
nhi_tx_schedule(struct nhi_ring_pair * r,struct nhi_cmd_frame * cmd)818 nhi_tx_schedule(struct nhi_ring_pair *r, struct nhi_cmd_frame *cmd)
819 {
820 	int error;
821 
822 	error = nhi_tx_enqueue(r, cmd);
823 	if (error == EBUSY)
824 		nhi_write_reg(r->sc, r->tx_pici_reg, r->tx_pi << TX_RING_PI_SHIFT | r->tx_ci);
825 	return (error);
826 }
827 
828 int
nhi_tx_synchronous(struct nhi_ring_pair * r,struct nhi_cmd_frame * cmd)829 nhi_tx_synchronous(struct nhi_ring_pair *r, struct nhi_cmd_frame *cmd)
830 {
831 	int error, count;
832 
833 	if ((error = nhi_tx_schedule(r, cmd)) != 0)
834 		return (error);
835 
836 	if (cmd->flags & CMD_POLLED) {
837 		error = 0;
838 		count = cmd->timeout * 100;
839 
840 		/* Enter the loop at least once */
841 		while ((count-- > 0) && (cmd->flags & CMD_REQ_COMPLETE) == 0) {
842 			DELAY(10000);
843 			rmb();
844 			nhi_intr(r->tracker);
845 		}
846 	} else {
847 		error = msleep(cmd, &r->mtx, PCATCH, "nhi_tx", cmd->timeout);
848 		if ((error == 0) && (cmd->flags & CMD_REQ_COMPLETE) != 0)
849 			error = EWOULDBLOCK;
850 	}
851 
852 	if ((cmd->flags & CMD_REQ_COMPLETE) == 0)
853 		error = ETIMEDOUT;
854 
855 	tb_debug(r->sc, DBG_TXQ|DBG_FULL, "tx_synchronous done waiting, "
856 	    "err= %d, TX_COMPLETE= %d\n", error,
857 	    !!(cmd->flags & CMD_REQ_COMPLETE));
858 
859 	if (error == ERESTART) {
860 		tb_printf(r->sc, "TX command interrupted\n");
861 	} else if ((error == EWOULDBLOCK) || (error == ETIMEDOUT)) {
862 		tb_printf(r->sc, "TX command timed out\n");
863 	} else if (error != 0) {
864 		tb_printf(r->sc, "TX command failed error= %d\n", error);
865 	}
866 
867 	return (error);
868 }
869 
870 static int
nhi_tx_complete(struct nhi_ring_pair * r,struct nhi_tx_buffer_desc * desc,struct nhi_cmd_frame * cmd)871 nhi_tx_complete(struct nhi_ring_pair *r, struct nhi_tx_buffer_desc *desc,
872     struct nhi_cmd_frame *cmd)
873 {
874 	struct nhi_softc *sc;
875 	struct nhi_pdf_dispatch *txpdf;
876 	u_int sof;
877 
878 	sc = r->sc;
879 	sof = desc->flags_sof & TX_BUFFER_DESC_SOF_MASK;
880 	tb_debug(sc, DBG_TXQ, "Recovered TX pdf= %s cmdidx= %d flags= 0x%x\n",
881 	    tb_get_string(sof, nhi_frame_pdf), cmd->idx, desc->flags_sof);
882 
883 	if ((desc->flags_sof & TX_BUFFER_DESC_DONE) == 0)
884 		tb_debug(sc, DBG_TXQ,
885 		    "warning, TX descriptor DONE flag not set\n");
886 
887 	/* XXX Atomics */
888 	cmd->flags |= CMD_REQ_COMPLETE;
889 
890 	txpdf = &r->tracker->txpdf[sof];
891 	if (txpdf->cb != NULL) {
892 		tb_debug(sc, DBG_INTR|DBG_TXQ, "Calling PDF TX callback\n");
893 		txpdf->cb(txpdf->context, (union nhi_ring_desc *)desc, cmd);
894 		return (0);
895 	}
896 
897 	tb_debug(sc, DBG_TXQ, "Unhandled TX complete %s\n",
898 	    tb_get_string(sof, nhi_frame_pdf));
899 	nhi_free_tx_frame(r, cmd);
900 
901 	return (0);
902 }
903 
904 static int
nhi_rx_complete(struct nhi_ring_pair * r,struct nhi_rx_post_desc * desc,struct nhi_cmd_frame * cmd)905 nhi_rx_complete(struct nhi_ring_pair *r, struct nhi_rx_post_desc *desc,
906     struct nhi_cmd_frame *cmd)
907 {
908 	struct nhi_softc *sc;
909 	struct nhi_pdf_dispatch *rxpdf;
910 	u_int eof, len;
911 
912 	sc = r->sc;
913 	eof = desc->eof_len >> RX_BUFFER_DESC_EOF_SHIFT;
914 	len = desc->eof_len & RX_BUFFER_DESC_LEN_MASK;
915 	tb_debug(sc, DBG_INTR|DBG_RXQ,
916 	    "Recovered RX pdf= %s len= %d cmdidx= %d, busaddr= 0x%jx\n",
917 	    tb_get_string(eof, nhi_frame_pdf), len, cmd->idx,
918 	    cmd->data_busaddr);
919 
920 	rxpdf = &r->tracker->rxpdf[eof];
921 	if (rxpdf->cb != NULL) {
922 		tb_debug(sc, DBG_INTR|DBG_RXQ, "Calling PDF RX callback\n");
923 		rxpdf->cb(rxpdf->context, (union nhi_ring_desc *)desc, cmd);
924 		return (0);
925 	}
926 
927 	tb_debug(sc, DBG_INTR, "Unhandled RX frame %s\n",
928 	    tb_get_string(eof, nhi_frame_pdf));
929 
930 	return (0);
931 }
932 
933 int
nhi_register_pdf(struct nhi_ring_pair * rp,struct nhi_dispatch * tx,struct nhi_dispatch * rx)934 nhi_register_pdf(struct nhi_ring_pair *rp, struct nhi_dispatch *tx,
935     struct nhi_dispatch *rx)
936 {
937 	struct nhi_intr_tracker *trkr;
938 	struct nhi_pdf_dispatch *slot;
939 
940 	KASSERT(rp != NULL, ("ring_pair is null\n"));
941 	tb_debug(rp->sc, DBG_INTR|DBG_EXTRA, "nhi_register_pdf called\n");
942 
943 	trkr = rp->tracker;
944 	if (trkr == NULL) {
945 		tb_debug(rp->sc, DBG_INTR, "Invalid tracker\n");
946 		return (EINVAL);
947 	}
948 
949 	tb_debug(rp->sc, DBG_INTR|DBG_EXTRA, "Registering TX interrupts\n");
950 	if (tx != NULL) {
951 		while (tx->cb != NULL) {
952 			if ((tx->pdf < 0) || (tx->pdf > 15))
953 				return (EINVAL);
954 			slot = &trkr->txpdf[tx->pdf];
955 			if (slot->cb != NULL) {
956 				tb_debug(rp->sc, DBG_INTR,
957 				    "Attempted to register busy callback\n");
958 				return (EBUSY);
959 			}
960 			slot->cb = tx->cb;
961 			slot->context = tx->context;
962 			tb_debug(rp->sc, DBG_INTR,
963 			    "Registered TX callback for PDF %d\n", tx->pdf);
964 			tx++;
965 		}
966 	}
967 
968 	tb_debug(rp->sc, DBG_INTR|DBG_EXTRA, "Registering RX interrupts\n");
969 	if (rx != NULL) {
970 		while (rx->cb != NULL) {
971 			if ((rx->pdf < 0) || (rx->pdf > 15))
972 				return (EINVAL);
973 			slot = &trkr->rxpdf[rx->pdf];
974 			if (slot->cb != NULL) {
975 				tb_debug(rp->sc, DBG_INTR,
976 				    "Attempted to register busy callback\n");
977 				return (EBUSY);
978 			}
979 			slot->cb = rx->cb;
980 			slot->context = rx->context;
981 			tb_debug(rp->sc, DBG_INTR,
982 			    "Registered RX callback for PDF %d\n", rx->pdf);
983 			rx++;
984 		}
985 	}
986 
987 	return (0);
988 }
989 
990 int
nhi_deregister_pdf(struct nhi_ring_pair * rp,struct nhi_dispatch * tx,struct nhi_dispatch * rx)991 nhi_deregister_pdf(struct nhi_ring_pair *rp, struct nhi_dispatch *tx,
992     struct nhi_dispatch *rx)
993 {
994 	struct nhi_intr_tracker *trkr;
995 	struct nhi_pdf_dispatch *slot;
996 
997 	tb_debug(rp->sc, DBG_INTR|DBG_EXTRA, "nhi_register_pdf called\n");
998 
999 	trkr = rp->tracker;
1000 
1001 	if (tx != NULL) {
1002 		while (tx->cb != NULL) {
1003 			if ((tx->pdf < 0) || (tx->pdf > 15))
1004 				return (EINVAL);
1005 			slot = &trkr->txpdf[tx->pdf];
1006 			slot->cb = NULL;
1007 			slot->context = NULL;
1008 			tx++;
1009 		}
1010 	}
1011 
1012 	if (rx != NULL) {
1013 		while (rx->cb != NULL) {
1014 			if ((rx->pdf < 0) || (rx->pdf > 15))
1015 				return (EINVAL);
1016 			slot = &trkr->rxpdf[rx->pdf];
1017 			slot->cb = NULL;
1018 			slot->context = NULL;
1019 			rx++;
1020 		}
1021 	}
1022 
1023 	return (0);
1024 }
1025 
1026 /*
1027  * The CI and PI indexes are not read from the hardware.  We track them in
1028  * software, so we know where in the ring to start a scan on an interrupt.
1029  * All we have to do is check for the appropriate Done bit in the next
1030  * descriptor, and we know if we have reached the last descriptor that the
1031  * hardware touched.  This technique saves at least 2 MEMIO reads per
1032  * interrupt.
1033  */
1034 void
nhi_intr(void * data)1035 nhi_intr(void *data)
1036 {
1037 	union nhi_ring_desc *rxd;
1038 	struct nhi_cmd_frame *cmd;
1039 	struct nhi_intr_tracker *trkr = data;
1040 	struct nhi_softc *sc;
1041 	struct nhi_ring_pair *r;
1042 	struct nhi_tx_buffer_desc *txd;
1043 	uint32_t val, old_ci;
1044 	u_int count;
1045 
1046 	sc = trkr->sc;
1047 
1048 	tb_debug(sc, DBG_INTR|DBG_FULL, "Interrupt @ vector %d\n",
1049 	    trkr->vector);
1050 	if ((r = trkr->ring) == NULL)
1051 		return;
1052 
1053 	/*
1054 	 * Process TX completions from the adapter.  Only go through
1055 	 * the ring once to prevent unbounded looping.
1056 	 */
1057 	count = r->tx_ring_depth;
1058 	while (count-- > 0) {
1059 		txd = &r->tx_ring[r->tx_ci].tx;
1060 		if ((txd->flags_sof & TX_BUFFER_DESC_DONE) == 0)
1061 			break;
1062 		cmd = r->tx_cmd_ring[r->tx_ci];
1063 		tb_debug(sc, DBG_INTR|DBG_TXQ|DBG_FULL,
1064 		    "Found tx cmdidx= %d cmd= %p\n", r->tx_ci, cmd);
1065 
1066 		/* Pass the completion up the stack */
1067 		nhi_tx_complete(r, txd, cmd);
1068 
1069 		/*
1070 		 * Advance to the next item in the ring via the cached
1071 		 * copy of the CI.  Clear the flags so we can detect
1072 		 * a new done condition the next time the ring wraps
1073 		 * around.  Anything higher up the stack that needs this
1074 		 * field should have already copied it.
1075 		 *
1076 		 * XXX is a memory barrier needed?
1077 		 */
1078 		txd->flags_sof = 0;
1079 		r->tx_ci = (r->tx_ci + 1) & r->tx_ring_mask;
1080 	}
1081 
1082 	/* Process RX packets from the adapter */
1083 	count = r->rx_ring_depth;
1084 	old_ci = r->rx_ci;
1085 
1086 	while (count-- > 0) {
1087 		tb_debug(sc, DBG_INTR|DBG_RXQ|DBG_FULL,
1088 		    "Checking RX descriptor at %d\n", r->rx_pi);
1089 
1090 		/* Look up RX descriptor and cmd */
1091 		rxd = &r->rx_ring[r->rx_pi];
1092 		tb_debug(sc, DBG_INTR|DBG_RXQ|DBG_FULL,
1093 		    "rx desc len= 0x%04x flags= 0x%04x\n", rxd->rxpost.eof_len,
1094 		    rxd->rxpost.flags_sof);
1095 		if ((rxd->rxpost.flags_sof & RX_BUFFER_DESC_DONE) == 0)
1096 			break;
1097 		cmd = r->rx_cmd_ring[r->rx_pi];
1098 		tb_debug(sc, DBG_INTR|DBG_RXQ|DBG_FULL,
1099 		    "Found rx cmdidx= %d cmd= %p\n", r->rx_pi, cmd);
1100 
1101 		/*
1102 		 * Pass the RX frame up the stack.  RX frames are re-used
1103 		 * in-place, so their contents must be copied before this
1104 		 * function returns.
1105 		 *
1106 		 * XXX Rings other than Ring0 might want to have a different
1107 		 * re-use and re-populate policy
1108 		 */
1109 		nhi_rx_complete(r, &rxd->rxpost, cmd);
1110 
1111 		/*
1112 		 * Advance the CI and move forward to the next item in the
1113 		 * ring via our cached copy of the PI.  Clear out the
1114 		 * length field so we can detect a new RX frame when the
1115 		 * ring wraps around.  Reset the flags of the descriptor.
1116 		 */
1117 		rxd->rxpost.eof_len = 0;
1118 		rxd->rx.flags = RX_BUFFER_DESC_RS | RX_BUFFER_DESC_IE;
1119 		r->rx_ci = (r->rx_ci + 1) & r->rx_ring_mask;
1120 		r->rx_pi = (r->rx_pi + 1) & r->rx_ring_mask;
1121 	}
1122 
1123 	/*
1124 	 * Tell the firmware about the new RX CI
1125 	 *
1126 	 * XXX There's a chance this will overwrite an update to the PI.
1127 	 * Is that OK?  We keep our own copy of the PI and never read it from
1128 	 * hardware.  However, will overwriting it result in a missed
1129 	 * interrupt?
1130 	 */
1131 	if (r->rx_ci != old_ci) {
1132 		val = r->rx_pi << RX_RING_PI_SHIFT | r->rx_ci;
1133 		tb_debug(sc, DBG_INTR | DBG_RXQ,
1134 		    "Writing new RX PICI= 0x%08x\n", val);
1135 		nhi_write_reg(sc, r->rx_pici_reg, val);
1136 	}
1137 }
1138 
1139 static int
nhi_setup_sysctl(struct nhi_softc * sc)1140 nhi_setup_sysctl(struct nhi_softc *sc)
1141 {
1142 	struct sysctl_ctx_list	*ctx = NULL;
1143 	struct sysctl_oid	*tree = NULL;
1144 
1145 	ctx = device_get_sysctl_ctx(sc->dev);
1146 	if (ctx != NULL)
1147 		tree = device_get_sysctl_tree(sc->dev);
1148 
1149 	/*
1150 	 * Not being able to create sysctls is going to hamper other
1151 	 * parts of the driver.
1152 	 */
1153 	if (tree == NULL) {
1154 		tb_printf(sc, "Error: cannot create sysctl nodes\n");
1155 		return (EINVAL);
1156 	}
1157 	sc->sysctl_tree = tree;
1158 	sc->sysctl_ctx = ctx;
1159 
1160 	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree),
1161 	    OID_AUTO, "debug_level", CTLTYPE_STRING|CTLFLAG_RW|CTLFLAG_MPSAFE,
1162 	    &sc->debug, 0, tb_debug_sysctl, "A", "Thunderbolt debug level");
1163 	SYSCTL_ADD_U16(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
1164 	    "max_rings", CTLFLAG_RD, &sc->max_ring_count, 0,
1165 	    "Max number of rings available");
1166 	SYSCTL_ADD_U8(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
1167 	    "force_hcm", CTLFLAG_RD, &sc->force_hcm, 0,
1168 	    "Force on/off the function of the host connection manager");
1169 
1170 	return (0);
1171 }
1172