1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Thunderbolt driver - NHI driver
4 *
5 * The NHI (native host interface) is the pci device that allows us to send and
6 * receive frames from the thunderbolt bus.
7 *
8 * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
9 * Copyright (C) 2018, Intel Corporation
10 */
11
12 #include <linux/pm_runtime.h>
13 #include <linux/slab.h>
14 #include <linux/errno.h>
15 #include <linux/pci.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/interrupt.h>
18 #include <linux/iommu.h>
19 #include <linux/module.h>
20 #include <linux/delay.h>
21 #include <linux/property.h>
22 #include <linux/string_helpers.h>
23
24 #include "nhi.h"
25 #include "nhi_regs.h"
26 #include "tb.h"
27
28 #define RING_TYPE(ring) ((ring)->is_tx ? "TX ring" : "RX ring")
29
30 #define RING_FIRST_USABLE_HOPID 1
31 /*
32 * Used with QUIRK_E2E to specify an unused HopID the Rx credits are
33 * transferred.
34 */
35 #define RING_E2E_RESERVED_HOPID RING_FIRST_USABLE_HOPID
36 /*
37 * Minimal number of vectors when we use MSI-X. Two for control channel
38 * Rx/Tx and the rest four are for cross domain DMA paths.
39 */
40 #define MSIX_MIN_VECS 6
41 #define MSIX_MAX_VECS 16
42
43 #define NHI_MAILBOX_TIMEOUT 500 /* ms */
44
45 /* Host interface quirks */
46 #define QUIRK_AUTO_CLEAR_INT BIT(0)
47 #define QUIRK_E2E BIT(1)
48
49 static bool host_reset = true;
50 module_param(host_reset, bool, 0444);
51 MODULE_PARM_DESC(host_reset, "reset USBv2 host router (default: true)");
52
ring_interrupt_index(const struct tb_ring * ring)53 static int ring_interrupt_index(const struct tb_ring *ring)
54 {
55 int bit = ring->hop;
56 if (!ring->is_tx)
57 bit += ring->nhi->hop_count;
58 return bit;
59 }
60
nhi_mask_interrupt(struct tb_nhi * nhi,int mask,int ring)61 static void nhi_mask_interrupt(struct tb_nhi *nhi, int mask, int ring)
62 {
63 if (nhi->quirks & QUIRK_AUTO_CLEAR_INT) {
64 u32 val;
65
66 val = ioread32(nhi->iobase + REG_RING_INTERRUPT_BASE + ring);
67 iowrite32(val & ~mask, nhi->iobase + REG_RING_INTERRUPT_BASE + ring);
68 } else {
69 iowrite32(mask, nhi->iobase + REG_RING_INTERRUPT_MASK_CLEAR_BASE + ring);
70 }
71 }
72
nhi_clear_interrupt(struct tb_nhi * nhi,int ring)73 static void nhi_clear_interrupt(struct tb_nhi *nhi, int ring)
74 {
75 if (nhi->quirks & QUIRK_AUTO_CLEAR_INT)
76 ioread32(nhi->iobase + REG_RING_NOTIFY_BASE + ring);
77 else
78 iowrite32(~0, nhi->iobase + REG_RING_INT_CLEAR + ring);
79 }
80
81 /*
82 * ring_interrupt_active() - activate/deactivate interrupts for a single ring
83 *
84 * ring->nhi->lock must be held.
85 */
ring_interrupt_active(struct tb_ring * ring,bool active)86 static void ring_interrupt_active(struct tb_ring *ring, bool active)
87 {
88 int index = ring_interrupt_index(ring) / 32 * 4;
89 int reg = REG_RING_INTERRUPT_BASE + index;
90 int interrupt_bit = ring_interrupt_index(ring) & 31;
91 int mask = 1 << interrupt_bit;
92 u32 old, new;
93
94 if (ring->irq > 0) {
95 u32 step, shift, ivr, misc;
96 void __iomem *ivr_base;
97 int auto_clear_bit;
98 int index;
99
100 if (ring->is_tx)
101 index = ring->hop;
102 else
103 index = ring->hop + ring->nhi->hop_count;
104
105 /*
106 * Intel routers support a bit that isn't part of
107 * the USB4 spec to ask the hardware to clear
108 * interrupt status bits automatically since
109 * we already know which interrupt was triggered.
110 *
111 * Other routers explicitly disable auto-clear
112 * to prevent conditions that may occur where two
113 * MSIX interrupts are simultaneously active and
114 * reading the register clears both of them.
115 */
116 misc = ioread32(ring->nhi->iobase + REG_DMA_MISC);
117 if (ring->nhi->quirks & QUIRK_AUTO_CLEAR_INT)
118 auto_clear_bit = REG_DMA_MISC_INT_AUTO_CLEAR;
119 else
120 auto_clear_bit = REG_DMA_MISC_DISABLE_AUTO_CLEAR;
121 if (!(misc & auto_clear_bit))
122 iowrite32(misc | auto_clear_bit,
123 ring->nhi->iobase + REG_DMA_MISC);
124
125 ivr_base = ring->nhi->iobase + REG_INT_VEC_ALLOC_BASE;
126 step = index / REG_INT_VEC_ALLOC_REGS * REG_INT_VEC_ALLOC_BITS;
127 shift = index % REG_INT_VEC_ALLOC_REGS * REG_INT_VEC_ALLOC_BITS;
128 ivr = ioread32(ivr_base + step);
129 ivr &= ~(REG_INT_VEC_ALLOC_MASK << shift);
130 if (active)
131 ivr |= ring->vector << shift;
132 iowrite32(ivr, ivr_base + step);
133 }
134
135 old = ioread32(ring->nhi->iobase + reg);
136 if (active)
137 new = old | mask;
138 else
139 new = old & ~mask;
140
141 dev_dbg(&ring->nhi->pdev->dev,
142 "%s interrupt at register %#x bit %d (%#x -> %#x)\n",
143 active ? "enabling" : "disabling", reg, interrupt_bit, old, new);
144
145 if (new == old)
146 dev_WARN(&ring->nhi->pdev->dev,
147 "interrupt for %s %d is already %s\n",
148 RING_TYPE(ring), ring->hop,
149 active ? "enabled" : "disabled");
150
151 if (active)
152 iowrite32(new, ring->nhi->iobase + reg);
153 else
154 nhi_mask_interrupt(ring->nhi, mask, index);
155 }
156
157 /*
158 * nhi_disable_interrupts() - disable interrupts for all rings
159 *
160 * Use only during init and shutdown.
161 */
nhi_disable_interrupts(struct tb_nhi * nhi)162 static void nhi_disable_interrupts(struct tb_nhi *nhi)
163 {
164 int i = 0;
165 /* disable interrupts */
166 for (i = 0; i < RING_INTERRUPT_REG_COUNT(nhi); i++)
167 nhi_mask_interrupt(nhi, ~0, 4 * i);
168
169 /* clear interrupt status bits */
170 for (i = 0; i < RING_NOTIFY_REG_COUNT(nhi); i++)
171 nhi_clear_interrupt(nhi, 4 * i);
172 }
173
174 /* ring helper methods */
175
ring_desc_base(struct tb_ring * ring)176 static void __iomem *ring_desc_base(struct tb_ring *ring)
177 {
178 void __iomem *io = ring->nhi->iobase;
179 io += ring->is_tx ? REG_TX_RING_BASE : REG_RX_RING_BASE;
180 io += ring->hop * 16;
181 return io;
182 }
183
ring_options_base(struct tb_ring * ring)184 static void __iomem *ring_options_base(struct tb_ring *ring)
185 {
186 void __iomem *io = ring->nhi->iobase;
187 io += ring->is_tx ? REG_TX_OPTIONS_BASE : REG_RX_OPTIONS_BASE;
188 io += ring->hop * 32;
189 return io;
190 }
191
ring_iowrite_cons(struct tb_ring * ring,u16 cons)192 static void ring_iowrite_cons(struct tb_ring *ring, u16 cons)
193 {
194 /*
195 * The other 16-bits in the register is read-only and writes to it
196 * are ignored by the hardware so we can save one ioread32() by
197 * filling the read-only bits with zeroes.
198 */
199 iowrite32(cons, ring_desc_base(ring) + 8);
200 }
201
ring_iowrite_prod(struct tb_ring * ring,u16 prod)202 static void ring_iowrite_prod(struct tb_ring *ring, u16 prod)
203 {
204 /* See ring_iowrite_cons() above for explanation */
205 iowrite32(prod << 16, ring_desc_base(ring) + 8);
206 }
207
ring_iowrite32desc(struct tb_ring * ring,u32 value,u32 offset)208 static void ring_iowrite32desc(struct tb_ring *ring, u32 value, u32 offset)
209 {
210 iowrite32(value, ring_desc_base(ring) + offset);
211 }
212
ring_iowrite64desc(struct tb_ring * ring,u64 value,u32 offset)213 static void ring_iowrite64desc(struct tb_ring *ring, u64 value, u32 offset)
214 {
215 iowrite32(value, ring_desc_base(ring) + offset);
216 iowrite32(value >> 32, ring_desc_base(ring) + offset + 4);
217 }
218
ring_iowrite32options(struct tb_ring * ring,u32 value,u32 offset)219 static void ring_iowrite32options(struct tb_ring *ring, u32 value, u32 offset)
220 {
221 iowrite32(value, ring_options_base(ring) + offset);
222 }
223
ring_full(struct tb_ring * ring)224 static bool ring_full(struct tb_ring *ring)
225 {
226 return ((ring->head + 1) % ring->size) == ring->tail;
227 }
228
ring_empty(struct tb_ring * ring)229 static bool ring_empty(struct tb_ring *ring)
230 {
231 return ring->head == ring->tail;
232 }
233
234 /*
235 * ring_write_descriptors() - post frames from ring->queue to the controller
236 *
237 * ring->lock is held.
238 */
ring_write_descriptors(struct tb_ring * ring)239 static void ring_write_descriptors(struct tb_ring *ring)
240 {
241 struct ring_frame *frame, *n;
242 struct ring_desc *descriptor;
243 list_for_each_entry_safe(frame, n, &ring->queue, list) {
244 if (ring_full(ring))
245 break;
246 list_move_tail(&frame->list, &ring->in_flight);
247 descriptor = &ring->descriptors[ring->head];
248 descriptor->phys = frame->buffer_phy;
249 descriptor->time = 0;
250 descriptor->flags = RING_DESC_POSTED | RING_DESC_INTERRUPT;
251 if (ring->is_tx) {
252 descriptor->length = frame->size;
253 descriptor->eof = frame->eof;
254 descriptor->sof = frame->sof;
255 }
256 ring->head = (ring->head + 1) % ring->size;
257 if (ring->is_tx)
258 ring_iowrite_prod(ring, ring->head);
259 else
260 ring_iowrite_cons(ring, ring->head);
261 }
262 }
263
264 /*
265 * ring_work() - progress completed frames
266 *
267 * If the ring is shutting down then all frames are marked as canceled and
268 * their callbacks are invoked.
269 *
270 * Otherwise we collect all completed frame from the ring buffer, write new
271 * frame to the ring buffer and invoke the callbacks for the completed frames.
272 */
ring_work(struct work_struct * work)273 static void ring_work(struct work_struct *work)
274 {
275 struct tb_ring *ring = container_of(work, typeof(*ring), work);
276 struct ring_frame *frame;
277 bool canceled = false;
278 unsigned long flags;
279 LIST_HEAD(done);
280
281 spin_lock_irqsave(&ring->lock, flags);
282
283 if (!ring->running) {
284 /* Move all frames to done and mark them as canceled. */
285 list_splice_tail_init(&ring->in_flight, &done);
286 list_splice_tail_init(&ring->queue, &done);
287 canceled = true;
288 goto invoke_callback;
289 }
290
291 while (!ring_empty(ring)) {
292 if (!(ring->descriptors[ring->tail].flags
293 & RING_DESC_COMPLETED))
294 break;
295 frame = list_first_entry(&ring->in_flight, typeof(*frame),
296 list);
297 list_move_tail(&frame->list, &done);
298 if (!ring->is_tx) {
299 frame->size = ring->descriptors[ring->tail].length;
300 frame->eof = ring->descriptors[ring->tail].eof;
301 frame->sof = ring->descriptors[ring->tail].sof;
302 frame->flags = ring->descriptors[ring->tail].flags;
303 }
304 ring->tail = (ring->tail + 1) % ring->size;
305 }
306 ring_write_descriptors(ring);
307
308 invoke_callback:
309 /* allow callbacks to schedule new work */
310 spin_unlock_irqrestore(&ring->lock, flags);
311 while (!list_empty(&done)) {
312 frame = list_first_entry(&done, typeof(*frame), list);
313 /*
314 * The callback may reenqueue or delete frame.
315 * Do not hold on to it.
316 */
317 list_del_init(&frame->list);
318 if (frame->callback)
319 frame->callback(ring, frame, canceled);
320 }
321 }
322
__tb_ring_enqueue(struct tb_ring * ring,struct ring_frame * frame)323 int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame)
324 {
325 unsigned long flags;
326 int ret = 0;
327
328 spin_lock_irqsave(&ring->lock, flags);
329 if (ring->running) {
330 list_add_tail(&frame->list, &ring->queue);
331 ring_write_descriptors(ring);
332 } else {
333 ret = -ESHUTDOWN;
334 }
335 spin_unlock_irqrestore(&ring->lock, flags);
336 return ret;
337 }
338 EXPORT_SYMBOL_GPL(__tb_ring_enqueue);
339
340 /**
341 * tb_ring_poll() - Poll one completed frame from the ring
342 * @ring: Ring to poll
343 *
344 * This function can be called when @start_poll callback of the @ring
345 * has been called. It will read one completed frame from the ring and
346 * return it to the caller. Returns %NULL if there is no more completed
347 * frames.
348 */
tb_ring_poll(struct tb_ring * ring)349 struct ring_frame *tb_ring_poll(struct tb_ring *ring)
350 {
351 struct ring_frame *frame = NULL;
352 unsigned long flags;
353
354 spin_lock_irqsave(&ring->lock, flags);
355 if (!ring->running)
356 goto unlock;
357 if (ring_empty(ring))
358 goto unlock;
359
360 if (ring->descriptors[ring->tail].flags & RING_DESC_COMPLETED) {
361 frame = list_first_entry(&ring->in_flight, typeof(*frame),
362 list);
363 list_del_init(&frame->list);
364
365 if (!ring->is_tx) {
366 frame->size = ring->descriptors[ring->tail].length;
367 frame->eof = ring->descriptors[ring->tail].eof;
368 frame->sof = ring->descriptors[ring->tail].sof;
369 frame->flags = ring->descriptors[ring->tail].flags;
370 }
371
372 ring->tail = (ring->tail + 1) % ring->size;
373 }
374
375 unlock:
376 spin_unlock_irqrestore(&ring->lock, flags);
377 return frame;
378 }
379 EXPORT_SYMBOL_GPL(tb_ring_poll);
380
__ring_interrupt_mask(struct tb_ring * ring,bool mask)381 static void __ring_interrupt_mask(struct tb_ring *ring, bool mask)
382 {
383 int idx = ring_interrupt_index(ring);
384 int reg = REG_RING_INTERRUPT_BASE + idx / 32 * 4;
385 int bit = idx % 32;
386 u32 val;
387
388 val = ioread32(ring->nhi->iobase + reg);
389 if (mask)
390 val &= ~BIT(bit);
391 else
392 val |= BIT(bit);
393 iowrite32(val, ring->nhi->iobase + reg);
394 }
395
396 /* Both @nhi->lock and @ring->lock should be held */
__ring_interrupt(struct tb_ring * ring)397 static void __ring_interrupt(struct tb_ring *ring)
398 {
399 if (!ring->running)
400 return;
401
402 if (ring->start_poll) {
403 __ring_interrupt_mask(ring, true);
404 ring->start_poll(ring->poll_data);
405 } else {
406 schedule_work(&ring->work);
407 }
408 }
409
410 /**
411 * tb_ring_poll_complete() - Re-start interrupt for the ring
412 * @ring: Ring to re-start the interrupt
413 *
414 * This will re-start (unmask) the ring interrupt once the user is done
415 * with polling.
416 */
tb_ring_poll_complete(struct tb_ring * ring)417 void tb_ring_poll_complete(struct tb_ring *ring)
418 {
419 unsigned long flags;
420
421 spin_lock_irqsave(&ring->nhi->lock, flags);
422 spin_lock(&ring->lock);
423 if (ring->start_poll)
424 __ring_interrupt_mask(ring, false);
425 spin_unlock(&ring->lock);
426 spin_unlock_irqrestore(&ring->nhi->lock, flags);
427 }
428 EXPORT_SYMBOL_GPL(tb_ring_poll_complete);
429
ring_clear_msix(const struct tb_ring * ring)430 static void ring_clear_msix(const struct tb_ring *ring)
431 {
432 int bit;
433
434 if (ring->nhi->quirks & QUIRK_AUTO_CLEAR_INT)
435 return;
436
437 bit = ring_interrupt_index(ring) & 31;
438 if (ring->is_tx)
439 iowrite32(BIT(bit), ring->nhi->iobase + REG_RING_INT_CLEAR);
440 else
441 iowrite32(BIT(bit), ring->nhi->iobase + REG_RING_INT_CLEAR +
442 4 * (ring->nhi->hop_count / 32));
443 }
444
ring_msix(int irq,void * data)445 static irqreturn_t ring_msix(int irq, void *data)
446 {
447 struct tb_ring *ring = data;
448
449 spin_lock(&ring->nhi->lock);
450 ring_clear_msix(ring);
451 spin_lock(&ring->lock);
452 __ring_interrupt(ring);
453 spin_unlock(&ring->lock);
454 spin_unlock(&ring->nhi->lock);
455
456 return IRQ_HANDLED;
457 }
458
ring_request_msix(struct tb_ring * ring,bool no_suspend)459 static int ring_request_msix(struct tb_ring *ring, bool no_suspend)
460 {
461 struct tb_nhi *nhi = ring->nhi;
462 unsigned long irqflags;
463 int ret;
464
465 if (!nhi->pdev->msix_enabled)
466 return 0;
467
468 ret = ida_simple_get(&nhi->msix_ida, 0, MSIX_MAX_VECS, GFP_KERNEL);
469 if (ret < 0)
470 return ret;
471
472 ring->vector = ret;
473
474 ret = pci_irq_vector(ring->nhi->pdev, ring->vector);
475 if (ret < 0)
476 goto err_ida_remove;
477
478 ring->irq = ret;
479
480 irqflags = no_suspend ? IRQF_NO_SUSPEND : 0;
481 ret = request_irq(ring->irq, ring_msix, irqflags, "thunderbolt", ring);
482 if (ret)
483 goto err_ida_remove;
484
485 return 0;
486
487 err_ida_remove:
488 ida_simple_remove(&nhi->msix_ida, ring->vector);
489
490 return ret;
491 }
492
ring_release_msix(struct tb_ring * ring)493 static void ring_release_msix(struct tb_ring *ring)
494 {
495 if (ring->irq <= 0)
496 return;
497
498 free_irq(ring->irq, ring);
499 ida_simple_remove(&ring->nhi->msix_ida, ring->vector);
500 ring->vector = 0;
501 ring->irq = 0;
502 }
503
nhi_alloc_hop(struct tb_nhi * nhi,struct tb_ring * ring)504 static int nhi_alloc_hop(struct tb_nhi *nhi, struct tb_ring *ring)
505 {
506 unsigned int start_hop = RING_FIRST_USABLE_HOPID;
507 int ret = 0;
508
509 if (nhi->quirks & QUIRK_E2E) {
510 start_hop = RING_FIRST_USABLE_HOPID + 1;
511 if (ring->flags & RING_FLAG_E2E && !ring->is_tx) {
512 dev_dbg(&nhi->pdev->dev, "quirking E2E TX HopID %u -> %u\n",
513 ring->e2e_tx_hop, RING_E2E_RESERVED_HOPID);
514 ring->e2e_tx_hop = RING_E2E_RESERVED_HOPID;
515 }
516 }
517
518 spin_lock_irq(&nhi->lock);
519
520 if (ring->hop < 0) {
521 unsigned int i;
522
523 /*
524 * Automatically allocate HopID from the non-reserved
525 * range 1 .. hop_count - 1.
526 */
527 for (i = start_hop; i < nhi->hop_count; i++) {
528 if (ring->is_tx) {
529 if (!nhi->tx_rings[i]) {
530 ring->hop = i;
531 break;
532 }
533 } else {
534 if (!nhi->rx_rings[i]) {
535 ring->hop = i;
536 break;
537 }
538 }
539 }
540 }
541
542 if (ring->hop > 0 && ring->hop < start_hop) {
543 dev_warn(&nhi->pdev->dev, "invalid hop: %d\n", ring->hop);
544 ret = -EINVAL;
545 goto err_unlock;
546 }
547 if (ring->hop < 0 || ring->hop >= nhi->hop_count) {
548 dev_warn(&nhi->pdev->dev, "invalid hop: %d\n", ring->hop);
549 ret = -EINVAL;
550 goto err_unlock;
551 }
552 if (ring->is_tx && nhi->tx_rings[ring->hop]) {
553 dev_warn(&nhi->pdev->dev, "TX hop %d already allocated\n",
554 ring->hop);
555 ret = -EBUSY;
556 goto err_unlock;
557 }
558 if (!ring->is_tx && nhi->rx_rings[ring->hop]) {
559 dev_warn(&nhi->pdev->dev, "RX hop %d already allocated\n",
560 ring->hop);
561 ret = -EBUSY;
562 goto err_unlock;
563 }
564
565 if (ring->is_tx)
566 nhi->tx_rings[ring->hop] = ring;
567 else
568 nhi->rx_rings[ring->hop] = ring;
569
570 err_unlock:
571 spin_unlock_irq(&nhi->lock);
572
573 return ret;
574 }
575
tb_ring_alloc(struct tb_nhi * nhi,u32 hop,int size,bool transmit,unsigned int flags,int e2e_tx_hop,u16 sof_mask,u16 eof_mask,void (* start_poll)(void *),void * poll_data)576 static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
577 bool transmit, unsigned int flags,
578 int e2e_tx_hop, u16 sof_mask, u16 eof_mask,
579 void (*start_poll)(void *),
580 void *poll_data)
581 {
582 struct tb_ring *ring = NULL;
583
584 dev_dbg(&nhi->pdev->dev, "allocating %s ring %d of size %d\n",
585 transmit ? "TX" : "RX", hop, size);
586
587 ring = kzalloc(sizeof(*ring), GFP_KERNEL);
588 if (!ring)
589 return NULL;
590
591 spin_lock_init(&ring->lock);
592 INIT_LIST_HEAD(&ring->queue);
593 INIT_LIST_HEAD(&ring->in_flight);
594 INIT_WORK(&ring->work, ring_work);
595
596 ring->nhi = nhi;
597 ring->hop = hop;
598 ring->is_tx = transmit;
599 ring->size = size;
600 ring->flags = flags;
601 ring->e2e_tx_hop = e2e_tx_hop;
602 ring->sof_mask = sof_mask;
603 ring->eof_mask = eof_mask;
604 ring->head = 0;
605 ring->tail = 0;
606 ring->running = false;
607 ring->start_poll = start_poll;
608 ring->poll_data = poll_data;
609
610 ring->descriptors = dma_alloc_coherent(&ring->nhi->pdev->dev,
611 size * sizeof(*ring->descriptors),
612 &ring->descriptors_dma, GFP_KERNEL | __GFP_ZERO);
613 if (!ring->descriptors)
614 goto err_free_ring;
615
616 if (ring_request_msix(ring, flags & RING_FLAG_NO_SUSPEND))
617 goto err_free_descs;
618
619 if (nhi_alloc_hop(nhi, ring))
620 goto err_release_msix;
621
622 return ring;
623
624 err_release_msix:
625 ring_release_msix(ring);
626 err_free_descs:
627 dma_free_coherent(&ring->nhi->pdev->dev,
628 ring->size * sizeof(*ring->descriptors),
629 ring->descriptors, ring->descriptors_dma);
630 err_free_ring:
631 kfree(ring);
632
633 return NULL;
634 }
635
636 /**
637 * tb_ring_alloc_tx() - Allocate DMA ring for transmit
638 * @nhi: Pointer to the NHI the ring is to be allocated
639 * @hop: HopID (ring) to allocate
640 * @size: Number of entries in the ring
641 * @flags: Flags for the ring
642 */
tb_ring_alloc_tx(struct tb_nhi * nhi,int hop,int size,unsigned int flags)643 struct tb_ring *tb_ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
644 unsigned int flags)
645 {
646 return tb_ring_alloc(nhi, hop, size, true, flags, 0, 0, 0, NULL, NULL);
647 }
648 EXPORT_SYMBOL_GPL(tb_ring_alloc_tx);
649
650 /**
651 * tb_ring_alloc_rx() - Allocate DMA ring for receive
652 * @nhi: Pointer to the NHI the ring is to be allocated
653 * @hop: HopID (ring) to allocate. Pass %-1 for automatic allocation.
654 * @size: Number of entries in the ring
655 * @flags: Flags for the ring
656 * @e2e_tx_hop: Transmit HopID when E2E is enabled in @flags
657 * @sof_mask: Mask of PDF values that start a frame
658 * @eof_mask: Mask of PDF values that end a frame
659 * @start_poll: If not %NULL the ring will call this function when an
660 * interrupt is triggered and masked, instead of callback
661 * in each Rx frame.
662 * @poll_data: Optional data passed to @start_poll
663 */
tb_ring_alloc_rx(struct tb_nhi * nhi,int hop,int size,unsigned int flags,int e2e_tx_hop,u16 sof_mask,u16 eof_mask,void (* start_poll)(void *),void * poll_data)664 struct tb_ring *tb_ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
665 unsigned int flags, int e2e_tx_hop,
666 u16 sof_mask, u16 eof_mask,
667 void (*start_poll)(void *), void *poll_data)
668 {
669 return tb_ring_alloc(nhi, hop, size, false, flags, e2e_tx_hop, sof_mask, eof_mask,
670 start_poll, poll_data);
671 }
672 EXPORT_SYMBOL_GPL(tb_ring_alloc_rx);
673
674 /**
675 * tb_ring_start() - enable a ring
676 * @ring: Ring to start
677 *
678 * Must not be invoked in parallel with tb_ring_stop().
679 */
tb_ring_start(struct tb_ring * ring)680 void tb_ring_start(struct tb_ring *ring)
681 {
682 u16 frame_size;
683 u32 flags;
684
685 spin_lock_irq(&ring->nhi->lock);
686 spin_lock(&ring->lock);
687 if (ring->nhi->going_away)
688 goto err;
689 if (ring->running) {
690 dev_WARN(&ring->nhi->pdev->dev, "ring already started\n");
691 goto err;
692 }
693 dev_dbg(&ring->nhi->pdev->dev, "starting %s %d\n",
694 RING_TYPE(ring), ring->hop);
695
696 if (ring->flags & RING_FLAG_FRAME) {
697 /* Means 4096 */
698 frame_size = 0;
699 flags = RING_FLAG_ENABLE;
700 } else {
701 frame_size = TB_FRAME_SIZE;
702 flags = RING_FLAG_ENABLE | RING_FLAG_RAW;
703 }
704
705 ring_iowrite64desc(ring, ring->descriptors_dma, 0);
706 if (ring->is_tx) {
707 ring_iowrite32desc(ring, ring->size, 12);
708 ring_iowrite32options(ring, 0, 4); /* time releated ? */
709 ring_iowrite32options(ring, flags, 0);
710 } else {
711 u32 sof_eof_mask = ring->sof_mask << 16 | ring->eof_mask;
712
713 ring_iowrite32desc(ring, (frame_size << 16) | ring->size, 12);
714 ring_iowrite32options(ring, sof_eof_mask, 4);
715 ring_iowrite32options(ring, flags, 0);
716 }
717
718 /*
719 * Now that the ring valid bit is set we can configure E2E if
720 * enabled for the ring.
721 */
722 if (ring->flags & RING_FLAG_E2E) {
723 if (!ring->is_tx) {
724 u32 hop;
725
726 hop = ring->e2e_tx_hop << REG_RX_OPTIONS_E2E_HOP_SHIFT;
727 hop &= REG_RX_OPTIONS_E2E_HOP_MASK;
728 flags |= hop;
729
730 dev_dbg(&ring->nhi->pdev->dev,
731 "enabling E2E for %s %d with TX HopID %d\n",
732 RING_TYPE(ring), ring->hop, ring->e2e_tx_hop);
733 } else {
734 dev_dbg(&ring->nhi->pdev->dev, "enabling E2E for %s %d\n",
735 RING_TYPE(ring), ring->hop);
736 }
737
738 flags |= RING_FLAG_E2E_FLOW_CONTROL;
739 ring_iowrite32options(ring, flags, 0);
740 }
741
742 ring_interrupt_active(ring, true);
743 ring->running = true;
744 err:
745 spin_unlock(&ring->lock);
746 spin_unlock_irq(&ring->nhi->lock);
747 }
748 EXPORT_SYMBOL_GPL(tb_ring_start);
749
750 /**
751 * tb_ring_stop() - shutdown a ring
752 * @ring: Ring to stop
753 *
754 * Must not be invoked from a callback.
755 *
756 * This method will disable the ring. Further calls to
757 * tb_ring_tx/tb_ring_rx will return -ESHUTDOWN until ring_stop has been
758 * called.
759 *
760 * All enqueued frames will be canceled and their callbacks will be executed
761 * with frame->canceled set to true (on the callback thread). This method
762 * returns only after all callback invocations have finished.
763 */
tb_ring_stop(struct tb_ring * ring)764 void tb_ring_stop(struct tb_ring *ring)
765 {
766 spin_lock_irq(&ring->nhi->lock);
767 spin_lock(&ring->lock);
768 dev_dbg(&ring->nhi->pdev->dev, "stopping %s %d\n",
769 RING_TYPE(ring), ring->hop);
770 if (ring->nhi->going_away)
771 goto err;
772 if (!ring->running) {
773 dev_WARN(&ring->nhi->pdev->dev, "%s %d already stopped\n",
774 RING_TYPE(ring), ring->hop);
775 goto err;
776 }
777 ring_interrupt_active(ring, false);
778
779 ring_iowrite32options(ring, 0, 0);
780 ring_iowrite64desc(ring, 0, 0);
781 ring_iowrite32desc(ring, 0, 8);
782 ring_iowrite32desc(ring, 0, 12);
783 ring->head = 0;
784 ring->tail = 0;
785 ring->running = false;
786
787 err:
788 spin_unlock(&ring->lock);
789 spin_unlock_irq(&ring->nhi->lock);
790
791 /*
792 * schedule ring->work to invoke callbacks on all remaining frames.
793 */
794 schedule_work(&ring->work);
795 flush_work(&ring->work);
796 }
797 EXPORT_SYMBOL_GPL(tb_ring_stop);
798
799 /*
800 * tb_ring_free() - free ring
801 *
802 * When this method returns all invocations of ring->callback will have
803 * finished.
804 *
805 * Ring must be stopped.
806 *
807 * Must NOT be called from ring_frame->callback!
808 */
tb_ring_free(struct tb_ring * ring)809 void tb_ring_free(struct tb_ring *ring)
810 {
811 spin_lock_irq(&ring->nhi->lock);
812 /*
813 * Dissociate the ring from the NHI. This also ensures that
814 * nhi_interrupt_work cannot reschedule ring->work.
815 */
816 if (ring->is_tx)
817 ring->nhi->tx_rings[ring->hop] = NULL;
818 else
819 ring->nhi->rx_rings[ring->hop] = NULL;
820
821 if (ring->running) {
822 dev_WARN(&ring->nhi->pdev->dev, "%s %d still running\n",
823 RING_TYPE(ring), ring->hop);
824 }
825 spin_unlock_irq(&ring->nhi->lock);
826
827 ring_release_msix(ring);
828
829 dma_free_coherent(&ring->nhi->pdev->dev,
830 ring->size * sizeof(*ring->descriptors),
831 ring->descriptors, ring->descriptors_dma);
832
833 ring->descriptors = NULL;
834 ring->descriptors_dma = 0;
835
836
837 dev_dbg(&ring->nhi->pdev->dev, "freeing %s %d\n", RING_TYPE(ring),
838 ring->hop);
839
840 /*
841 * ring->work can no longer be scheduled (it is scheduled only
842 * by nhi_interrupt_work, ring_stop and ring_msix). Wait for it
843 * to finish before freeing the ring.
844 */
845 flush_work(&ring->work);
846 kfree(ring);
847 }
848 EXPORT_SYMBOL_GPL(tb_ring_free);
849
850 /**
851 * nhi_mailbox_cmd() - Send a command through NHI mailbox
852 * @nhi: Pointer to the NHI structure
853 * @cmd: Command to send
854 * @data: Data to be send with the command
855 *
856 * Sends mailbox command to the firmware running on NHI. Returns %0 in
857 * case of success and negative errno in case of failure.
858 */
nhi_mailbox_cmd(struct tb_nhi * nhi,enum nhi_mailbox_cmd cmd,u32 data)859 int nhi_mailbox_cmd(struct tb_nhi *nhi, enum nhi_mailbox_cmd cmd, u32 data)
860 {
861 ktime_t timeout;
862 u32 val;
863
864 iowrite32(data, nhi->iobase + REG_INMAIL_DATA);
865
866 val = ioread32(nhi->iobase + REG_INMAIL_CMD);
867 val &= ~(REG_INMAIL_CMD_MASK | REG_INMAIL_ERROR);
868 val |= REG_INMAIL_OP_REQUEST | cmd;
869 iowrite32(val, nhi->iobase + REG_INMAIL_CMD);
870
871 timeout = ktime_add_ms(ktime_get(), NHI_MAILBOX_TIMEOUT);
872 do {
873 val = ioread32(nhi->iobase + REG_INMAIL_CMD);
874 if (!(val & REG_INMAIL_OP_REQUEST))
875 break;
876 usleep_range(10, 20);
877 } while (ktime_before(ktime_get(), timeout));
878
879 if (val & REG_INMAIL_OP_REQUEST)
880 return -ETIMEDOUT;
881 if (val & REG_INMAIL_ERROR)
882 return -EIO;
883
884 return 0;
885 }
886
887 /**
888 * nhi_mailbox_mode() - Return current firmware operation mode
889 * @nhi: Pointer to the NHI structure
890 *
891 * The function reads current firmware operation mode using NHI mailbox
892 * registers and returns it to the caller.
893 */
nhi_mailbox_mode(struct tb_nhi * nhi)894 enum nhi_fw_mode nhi_mailbox_mode(struct tb_nhi *nhi)
895 {
896 u32 val;
897
898 val = ioread32(nhi->iobase + REG_OUTMAIL_CMD);
899 val &= REG_OUTMAIL_CMD_OPMODE_MASK;
900 val >>= REG_OUTMAIL_CMD_OPMODE_SHIFT;
901
902 return (enum nhi_fw_mode)val;
903 }
904
nhi_interrupt_work(struct work_struct * work)905 static void nhi_interrupt_work(struct work_struct *work)
906 {
907 struct tb_nhi *nhi = container_of(work, typeof(*nhi), interrupt_work);
908 int value = 0; /* Suppress uninitialized usage warning. */
909 int bit;
910 int hop = -1;
911 int type = 0; /* current interrupt type 0: TX, 1: RX, 2: RX overflow */
912 struct tb_ring *ring;
913
914 spin_lock_irq(&nhi->lock);
915
916 /*
917 * Starting at REG_RING_NOTIFY_BASE there are three status bitfields
918 * (TX, RX, RX overflow). We iterate over the bits and read a new
919 * dwords as required. The registers are cleared on read.
920 */
921 for (bit = 0; bit < 3 * nhi->hop_count; bit++) {
922 if (bit % 32 == 0)
923 value = ioread32(nhi->iobase
924 + REG_RING_NOTIFY_BASE
925 + 4 * (bit / 32));
926 if (++hop == nhi->hop_count) {
927 hop = 0;
928 type++;
929 }
930 if ((value & (1 << (bit % 32))) == 0)
931 continue;
932 if (type == 2) {
933 dev_warn(&nhi->pdev->dev,
934 "RX overflow for ring %d\n",
935 hop);
936 continue;
937 }
938 if (type == 0)
939 ring = nhi->tx_rings[hop];
940 else
941 ring = nhi->rx_rings[hop];
942 if (ring == NULL) {
943 dev_warn(&nhi->pdev->dev,
944 "got interrupt for inactive %s ring %d\n",
945 type ? "RX" : "TX",
946 hop);
947 continue;
948 }
949
950 spin_lock(&ring->lock);
951 __ring_interrupt(ring);
952 spin_unlock(&ring->lock);
953 }
954 spin_unlock_irq(&nhi->lock);
955 }
956
nhi_msi(int irq,void * data)957 static irqreturn_t nhi_msi(int irq, void *data)
958 {
959 struct tb_nhi *nhi = data;
960 schedule_work(&nhi->interrupt_work);
961 return IRQ_HANDLED;
962 }
963
__nhi_suspend_noirq(struct device * dev,bool wakeup)964 static int __nhi_suspend_noirq(struct device *dev, bool wakeup)
965 {
966 struct pci_dev *pdev = to_pci_dev(dev);
967 struct tb *tb = pci_get_drvdata(pdev);
968 struct tb_nhi *nhi = tb->nhi;
969 int ret;
970
971 ret = tb_domain_suspend_noirq(tb);
972 if (ret)
973 return ret;
974
975 if (nhi->ops && nhi->ops->suspend_noirq) {
976 ret = nhi->ops->suspend_noirq(tb->nhi, wakeup);
977 if (ret)
978 return ret;
979 }
980
981 return 0;
982 }
983
nhi_suspend_noirq(struct device * dev)984 static int nhi_suspend_noirq(struct device *dev)
985 {
986 return __nhi_suspend_noirq(dev, device_may_wakeup(dev));
987 }
988
nhi_freeze_noirq(struct device * dev)989 static int nhi_freeze_noirq(struct device *dev)
990 {
991 struct pci_dev *pdev = to_pci_dev(dev);
992 struct tb *tb = pci_get_drvdata(pdev);
993
994 return tb_domain_freeze_noirq(tb);
995 }
996
nhi_thaw_noirq(struct device * dev)997 static int nhi_thaw_noirq(struct device *dev)
998 {
999 struct pci_dev *pdev = to_pci_dev(dev);
1000 struct tb *tb = pci_get_drvdata(pdev);
1001
1002 return tb_domain_thaw_noirq(tb);
1003 }
1004
nhi_wake_supported(struct pci_dev * pdev)1005 static bool nhi_wake_supported(struct pci_dev *pdev)
1006 {
1007 u8 val;
1008
1009 /*
1010 * If power rails are sustainable for wakeup from S4 this
1011 * property is set by the BIOS.
1012 */
1013 if (device_property_read_u8(&pdev->dev, "WAKE_SUPPORTED", &val))
1014 return !!val;
1015
1016 return true;
1017 }
1018
nhi_poweroff_noirq(struct device * dev)1019 static int nhi_poweroff_noirq(struct device *dev)
1020 {
1021 struct pci_dev *pdev = to_pci_dev(dev);
1022 bool wakeup;
1023
1024 wakeup = device_may_wakeup(dev) && nhi_wake_supported(pdev);
1025 return __nhi_suspend_noirq(dev, wakeup);
1026 }
1027
nhi_enable_int_throttling(struct tb_nhi * nhi)1028 static void nhi_enable_int_throttling(struct tb_nhi *nhi)
1029 {
1030 /* Throttling is specified in 256ns increments */
1031 u32 throttle = DIV_ROUND_UP(128 * NSEC_PER_USEC, 256);
1032 unsigned int i;
1033
1034 /*
1035 * Configure interrupt throttling for all vectors even if we
1036 * only use few.
1037 */
1038 for (i = 0; i < MSIX_MAX_VECS; i++) {
1039 u32 reg = REG_INT_THROTTLING_RATE + i * 4;
1040 iowrite32(throttle, nhi->iobase + reg);
1041 }
1042 }
1043
nhi_resume_noirq(struct device * dev)1044 static int nhi_resume_noirq(struct device *dev)
1045 {
1046 struct pci_dev *pdev = to_pci_dev(dev);
1047 struct tb *tb = pci_get_drvdata(pdev);
1048 struct tb_nhi *nhi = tb->nhi;
1049 int ret;
1050
1051 /*
1052 * Check that the device is still there. It may be that the user
1053 * unplugged last device which causes the host controller to go
1054 * away on PCs.
1055 */
1056 if (!pci_device_is_present(pdev)) {
1057 nhi->going_away = true;
1058 } else {
1059 if (nhi->ops && nhi->ops->resume_noirq) {
1060 ret = nhi->ops->resume_noirq(nhi);
1061 if (ret)
1062 return ret;
1063 }
1064 nhi_enable_int_throttling(tb->nhi);
1065 }
1066
1067 return tb_domain_resume_noirq(tb);
1068 }
1069
nhi_suspend(struct device * dev)1070 static int nhi_suspend(struct device *dev)
1071 {
1072 struct pci_dev *pdev = to_pci_dev(dev);
1073 struct tb *tb = pci_get_drvdata(pdev);
1074
1075 return tb_domain_suspend(tb);
1076 }
1077
nhi_complete(struct device * dev)1078 static void nhi_complete(struct device *dev)
1079 {
1080 struct pci_dev *pdev = to_pci_dev(dev);
1081 struct tb *tb = pci_get_drvdata(pdev);
1082
1083 /*
1084 * If we were runtime suspended when system suspend started,
1085 * schedule runtime resume now. It should bring the domain back
1086 * to functional state.
1087 */
1088 if (pm_runtime_suspended(&pdev->dev))
1089 pm_runtime_resume(&pdev->dev);
1090 else
1091 tb_domain_complete(tb);
1092 }
1093
nhi_runtime_suspend(struct device * dev)1094 static int nhi_runtime_suspend(struct device *dev)
1095 {
1096 struct pci_dev *pdev = to_pci_dev(dev);
1097 struct tb *tb = pci_get_drvdata(pdev);
1098 struct tb_nhi *nhi = tb->nhi;
1099 int ret;
1100
1101 ret = tb_domain_runtime_suspend(tb);
1102 if (ret)
1103 return ret;
1104
1105 if (nhi->ops && nhi->ops->runtime_suspend) {
1106 ret = nhi->ops->runtime_suspend(tb->nhi);
1107 if (ret)
1108 return ret;
1109 }
1110 return 0;
1111 }
1112
nhi_runtime_resume(struct device * dev)1113 static int nhi_runtime_resume(struct device *dev)
1114 {
1115 struct pci_dev *pdev = to_pci_dev(dev);
1116 struct tb *tb = pci_get_drvdata(pdev);
1117 struct tb_nhi *nhi = tb->nhi;
1118 int ret;
1119
1120 if (nhi->ops && nhi->ops->runtime_resume) {
1121 ret = nhi->ops->runtime_resume(nhi);
1122 if (ret)
1123 return ret;
1124 }
1125
1126 nhi_enable_int_throttling(nhi);
1127 return tb_domain_runtime_resume(tb);
1128 }
1129
nhi_shutdown(struct tb_nhi * nhi)1130 static void nhi_shutdown(struct tb_nhi *nhi)
1131 {
1132 int i;
1133
1134 dev_dbg(&nhi->pdev->dev, "shutdown\n");
1135
1136 for (i = 0; i < nhi->hop_count; i++) {
1137 if (nhi->tx_rings[i])
1138 dev_WARN(&nhi->pdev->dev,
1139 "TX ring %d is still active\n", i);
1140 if (nhi->rx_rings[i])
1141 dev_WARN(&nhi->pdev->dev,
1142 "RX ring %d is still active\n", i);
1143 }
1144 nhi_disable_interrupts(nhi);
1145 /*
1146 * We have to release the irq before calling flush_work. Otherwise an
1147 * already executing IRQ handler could call schedule_work again.
1148 */
1149 if (!nhi->pdev->msix_enabled) {
1150 devm_free_irq(&nhi->pdev->dev, nhi->pdev->irq, nhi);
1151 flush_work(&nhi->interrupt_work);
1152 }
1153 ida_destroy(&nhi->msix_ida);
1154
1155 if (nhi->ops && nhi->ops->shutdown)
1156 nhi->ops->shutdown(nhi);
1157 }
1158
nhi_check_quirks(struct tb_nhi * nhi)1159 static void nhi_check_quirks(struct tb_nhi *nhi)
1160 {
1161 if (nhi->pdev->vendor == PCI_VENDOR_ID_INTEL) {
1162 /*
1163 * Intel hardware supports auto clear of the interrupt
1164 * status register right after interrupt is being
1165 * issued.
1166 */
1167 nhi->quirks |= QUIRK_AUTO_CLEAR_INT;
1168
1169 switch (nhi->pdev->device) {
1170 case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_2C_NHI:
1171 case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_NHI:
1172 /*
1173 * Falcon Ridge controller needs the end-to-end
1174 * flow control workaround to avoid losing Rx
1175 * packets when RING_FLAG_E2E is set.
1176 */
1177 nhi->quirks |= QUIRK_E2E;
1178 break;
1179 }
1180 }
1181 }
1182
nhi_check_iommu_pdev(struct pci_dev * pdev,void * data)1183 static int nhi_check_iommu_pdev(struct pci_dev *pdev, void *data)
1184 {
1185 if (!pdev->external_facing ||
1186 !device_iommu_capable(&pdev->dev, IOMMU_CAP_PRE_BOOT_PROTECTION))
1187 return 0;
1188 *(bool *)data = true;
1189 return 1; /* Stop walking */
1190 }
1191
nhi_check_iommu(struct tb_nhi * nhi)1192 static void nhi_check_iommu(struct tb_nhi *nhi)
1193 {
1194 struct pci_bus *bus = nhi->pdev->bus;
1195 bool port_ok = false;
1196
1197 /*
1198 * Ideally what we'd do here is grab every PCI device that
1199 * represents a tunnelling adapter for this NHI and check their
1200 * status directly, but unfortunately USB4 seems to make it
1201 * obnoxiously difficult to reliably make any correlation.
1202 *
1203 * So for now we'll have to bodge it... Hoping that the system
1204 * is at least sane enough that an adapter is in the same PCI
1205 * segment as its NHI, if we can find *something* on that segment
1206 * which meets the requirements for Kernel DMA Protection, we'll
1207 * take that to imply that firmware is aware and has (hopefully)
1208 * done the right thing in general. We need to know that the PCI
1209 * layer has seen the ExternalFacingPort property which will then
1210 * inform the IOMMU layer to enforce the complete "untrusted DMA"
1211 * flow, but also that the IOMMU driver itself can be trusted not
1212 * to have been subverted by a pre-boot DMA attack.
1213 */
1214 while (bus->parent)
1215 bus = bus->parent;
1216
1217 pci_walk_bus(bus, nhi_check_iommu_pdev, &port_ok);
1218
1219 nhi->iommu_dma_protection = port_ok;
1220 dev_dbg(&nhi->pdev->dev, "IOMMU DMA protection is %s\n",
1221 str_enabled_disabled(port_ok));
1222 }
1223
nhi_reset(struct tb_nhi * nhi)1224 static bool nhi_reset(struct tb_nhi *nhi)
1225 {
1226 ktime_t timeout;
1227 u32 val;
1228
1229 val = ioread32(nhi->iobase + REG_CAPS);
1230 /* Reset only v2 and later routers */
1231 if (FIELD_GET(REG_CAPS_VERSION_MASK, val) < REG_CAPS_VERSION_2)
1232 return false;
1233
1234 if (!host_reset) {
1235 dev_dbg(&nhi->pdev->dev, "skipping host router reset\n");
1236 return false;
1237 }
1238
1239 iowrite32(REG_RESET_HRR, nhi->iobase + REG_RESET);
1240 msleep(100);
1241
1242 timeout = ktime_add_ms(ktime_get(), 500);
1243 do {
1244 val = ioread32(nhi->iobase + REG_RESET);
1245 if (!(val & REG_RESET_HRR)) {
1246 dev_warn(&nhi->pdev->dev, "host router reset successful\n");
1247 return true;
1248 }
1249 usleep_range(10, 20);
1250 } while (ktime_before(ktime_get(), timeout));
1251
1252 dev_warn(&nhi->pdev->dev, "timeout resetting host router\n");
1253
1254 return false;
1255 }
1256
nhi_init_msi(struct tb_nhi * nhi)1257 static int nhi_init_msi(struct tb_nhi *nhi)
1258 {
1259 struct pci_dev *pdev = nhi->pdev;
1260 struct device *dev = &pdev->dev;
1261 int res, irq, nvec;
1262
1263 /* In case someone left them on. */
1264 nhi_disable_interrupts(nhi);
1265
1266 nhi_enable_int_throttling(nhi);
1267
1268 ida_init(&nhi->msix_ida);
1269
1270 /*
1271 * The NHI has 16 MSI-X vectors or a single MSI. We first try to
1272 * get all MSI-X vectors and if we succeed, each ring will have
1273 * one MSI-X. If for some reason that does not work out, we
1274 * fallback to a single MSI.
1275 */
1276 nvec = pci_alloc_irq_vectors(pdev, MSIX_MIN_VECS, MSIX_MAX_VECS,
1277 PCI_IRQ_MSIX);
1278 if (nvec < 0) {
1279 nvec = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
1280 if (nvec < 0)
1281 return nvec;
1282
1283 INIT_WORK(&nhi->interrupt_work, nhi_interrupt_work);
1284
1285 irq = pci_irq_vector(nhi->pdev, 0);
1286 if (irq < 0)
1287 return irq;
1288
1289 res = devm_request_irq(&pdev->dev, irq, nhi_msi,
1290 IRQF_NO_SUSPEND, "thunderbolt", nhi);
1291 if (res)
1292 return dev_err_probe(dev, res, "request_irq failed, aborting\n");
1293 }
1294
1295 return 0;
1296 }
1297
nhi_imr_valid(struct pci_dev * pdev)1298 static bool nhi_imr_valid(struct pci_dev *pdev)
1299 {
1300 u8 val;
1301
1302 if (!device_property_read_u8(&pdev->dev, "IMR_VALID", &val))
1303 return !!val;
1304
1305 return true;
1306 }
1307
nhi_select_cm(struct tb_nhi * nhi)1308 static struct tb *nhi_select_cm(struct tb_nhi *nhi)
1309 {
1310 struct tb *tb;
1311
1312 /*
1313 * USB4 case is simple. If we got control of any of the
1314 * capabilities, we use software CM.
1315 */
1316 if (tb_acpi_is_native())
1317 return tb_probe(nhi);
1318
1319 /*
1320 * Either firmware based CM is running (we did not get control
1321 * from the firmware) or this is pre-USB4 PC so try first
1322 * firmware CM and then fallback to software CM.
1323 */
1324 tb = icm_probe(nhi);
1325 if (!tb)
1326 tb = tb_probe(nhi);
1327
1328 return tb;
1329 }
1330
nhi_probe(struct pci_dev * pdev,const struct pci_device_id * id)1331 static int nhi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
1332 {
1333 struct device *dev = &pdev->dev;
1334 struct tb_nhi *nhi;
1335 struct tb *tb;
1336 bool reset;
1337 int res;
1338
1339 if (!nhi_imr_valid(pdev))
1340 return dev_err_probe(dev, -ENODEV, "firmware image not valid, aborting\n");
1341
1342 res = pcim_enable_device(pdev);
1343 if (res)
1344 return dev_err_probe(dev, res, "cannot enable PCI device, aborting\n");
1345
1346 res = pcim_iomap_regions(pdev, 1 << 0, "thunderbolt");
1347 if (res)
1348 return dev_err_probe(dev, res, "cannot obtain PCI resources, aborting\n");
1349
1350 nhi = devm_kzalloc(&pdev->dev, sizeof(*nhi), GFP_KERNEL);
1351 if (!nhi)
1352 return -ENOMEM;
1353
1354 nhi->pdev = pdev;
1355 nhi->ops = (const struct tb_nhi_ops *)id->driver_data;
1356 /* cannot fail - table is allocated in pcim_iomap_regions */
1357 nhi->iobase = pcim_iomap_table(pdev)[0];
1358 nhi->hop_count = ioread32(nhi->iobase + REG_CAPS) & 0x3ff;
1359 dev_dbg(dev, "total paths: %d\n", nhi->hop_count);
1360
1361 nhi->tx_rings = devm_kcalloc(&pdev->dev, nhi->hop_count,
1362 sizeof(*nhi->tx_rings), GFP_KERNEL);
1363 nhi->rx_rings = devm_kcalloc(&pdev->dev, nhi->hop_count,
1364 sizeof(*nhi->rx_rings), GFP_KERNEL);
1365 if (!nhi->tx_rings || !nhi->rx_rings)
1366 return -ENOMEM;
1367
1368 nhi_check_quirks(nhi);
1369 nhi_check_iommu(nhi);
1370
1371 /*
1372 * Only USB4 v2 hosts support host reset so if we already did
1373 * that then don't do it again when the domain is initialized.
1374 */
1375 reset = nhi_reset(nhi) ? false : host_reset;
1376
1377 res = nhi_init_msi(nhi);
1378 if (res)
1379 return dev_err_probe(dev, res, "cannot enable MSI, aborting\n");
1380
1381 spin_lock_init(&nhi->lock);
1382
1383 res = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
1384 if (res)
1385 return dev_err_probe(dev, res, "failed to set DMA mask\n");
1386
1387 pci_set_master(pdev);
1388
1389 if (nhi->ops && nhi->ops->init) {
1390 res = nhi->ops->init(nhi);
1391 if (res)
1392 return res;
1393 }
1394
1395 tb = nhi_select_cm(nhi);
1396 if (!tb)
1397 return dev_err_probe(dev, -ENODEV,
1398 "failed to determine connection manager, aborting\n");
1399
1400 dev_dbg(dev, "NHI initialized, starting thunderbolt\n");
1401
1402 res = tb_domain_add(tb, reset);
1403 if (res) {
1404 /*
1405 * At this point the RX/TX rings might already have been
1406 * activated. Do a proper shutdown.
1407 */
1408 tb_domain_put(tb);
1409 nhi_shutdown(nhi);
1410 return res;
1411 }
1412 pci_set_drvdata(pdev, tb);
1413
1414 device_wakeup_enable(&pdev->dev);
1415
1416 pm_runtime_allow(&pdev->dev);
1417 pm_runtime_set_autosuspend_delay(&pdev->dev, TB_AUTOSUSPEND_DELAY);
1418 pm_runtime_use_autosuspend(&pdev->dev);
1419 pm_runtime_put_autosuspend(&pdev->dev);
1420
1421 return 0;
1422 }
1423
nhi_remove(struct pci_dev * pdev)1424 static void nhi_remove(struct pci_dev *pdev)
1425 {
1426 struct tb *tb = pci_get_drvdata(pdev);
1427 struct tb_nhi *nhi = tb->nhi;
1428
1429 pm_runtime_get_sync(&pdev->dev);
1430 pm_runtime_dont_use_autosuspend(&pdev->dev);
1431 pm_runtime_forbid(&pdev->dev);
1432
1433 tb_domain_remove(tb);
1434 nhi_shutdown(nhi);
1435 }
1436
1437 /*
1438 * The tunneled pci bridges are siblings of us. Use resume_noirq to reenable
1439 * the tunnels asap. A corresponding pci quirk blocks the downstream bridges
1440 * resume_noirq until we are done.
1441 */
1442 static const struct dev_pm_ops nhi_pm_ops = {
1443 .suspend_noirq = nhi_suspend_noirq,
1444 .resume_noirq = nhi_resume_noirq,
1445 .freeze_noirq = nhi_freeze_noirq, /*
1446 * we just disable hotplug, the
1447 * pci-tunnels stay alive.
1448 */
1449 .thaw_noirq = nhi_thaw_noirq,
1450 .restore_noirq = nhi_resume_noirq,
1451 .suspend = nhi_suspend,
1452 .poweroff_noirq = nhi_poweroff_noirq,
1453 .poweroff = nhi_suspend,
1454 .complete = nhi_complete,
1455 .runtime_suspend = nhi_runtime_suspend,
1456 .runtime_resume = nhi_runtime_resume,
1457 };
1458
1459 static struct pci_device_id nhi_ids[] = {
1460 /*
1461 * We have to specify class, the TB bridges use the same device and
1462 * vendor (sub)id on gen 1 and gen 2 controllers.
1463 */
1464 {
1465 .class = PCI_CLASS_SYSTEM_OTHER << 8, .class_mask = ~0,
1466 .vendor = PCI_VENDOR_ID_INTEL,
1467 .device = PCI_DEVICE_ID_INTEL_LIGHT_RIDGE,
1468 .subvendor = 0x2222, .subdevice = 0x1111,
1469 },
1470 {
1471 .class = PCI_CLASS_SYSTEM_OTHER << 8, .class_mask = ~0,
1472 .vendor = PCI_VENDOR_ID_INTEL,
1473 .device = PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C,
1474 .subvendor = 0x2222, .subdevice = 0x1111,
1475 },
1476 {
1477 .class = PCI_CLASS_SYSTEM_OTHER << 8, .class_mask = ~0,
1478 .vendor = PCI_VENDOR_ID_INTEL,
1479 .device = PCI_DEVICE_ID_INTEL_FALCON_RIDGE_2C_NHI,
1480 .subvendor = PCI_ANY_ID, .subdevice = PCI_ANY_ID,
1481 },
1482 {
1483 .class = PCI_CLASS_SYSTEM_OTHER << 8, .class_mask = ~0,
1484 .vendor = PCI_VENDOR_ID_INTEL,
1485 .device = PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_NHI,
1486 .subvendor = PCI_ANY_ID, .subdevice = PCI_ANY_ID,
1487 },
1488
1489 /* Thunderbolt 3 */
1490 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_2C_NHI) },
1491 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_4C_NHI) },
1492 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_USBONLY_NHI) },
1493 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_LP_NHI) },
1494 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_LP_USBONLY_NHI) },
1495 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_2C_NHI) },
1496 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_4C_NHI) },
1497 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_USBONLY_NHI) },
1498 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_TITAN_RIDGE_2C_NHI) },
1499 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_TITAN_RIDGE_4C_NHI) },
1500 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ICL_NHI0),
1501 .driver_data = (kernel_ulong_t)&icl_nhi_ops },
1502 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ICL_NHI1),
1503 .driver_data = (kernel_ulong_t)&icl_nhi_ops },
1504 /* Thunderbolt 4 */
1505 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_TGL_NHI0),
1506 .driver_data = (kernel_ulong_t)&icl_nhi_ops },
1507 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_TGL_NHI1),
1508 .driver_data = (kernel_ulong_t)&icl_nhi_ops },
1509 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_TGL_H_NHI0),
1510 .driver_data = (kernel_ulong_t)&icl_nhi_ops },
1511 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_TGL_H_NHI1),
1512 .driver_data = (kernel_ulong_t)&icl_nhi_ops },
1513 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ADL_NHI0),
1514 .driver_data = (kernel_ulong_t)&icl_nhi_ops },
1515 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ADL_NHI1),
1516 .driver_data = (kernel_ulong_t)&icl_nhi_ops },
1517 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_RPL_NHI0),
1518 .driver_data = (kernel_ulong_t)&icl_nhi_ops },
1519 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_RPL_NHI1),
1520 .driver_data = (kernel_ulong_t)&icl_nhi_ops },
1521 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MTL_M_NHI0),
1522 .driver_data = (kernel_ulong_t)&icl_nhi_ops },
1523 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MTL_P_NHI0),
1524 .driver_data = (kernel_ulong_t)&icl_nhi_ops },
1525 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MTL_P_NHI1),
1526 .driver_data = (kernel_ulong_t)&icl_nhi_ops },
1527 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_BARLOW_RIDGE_HOST_80G_NHI) },
1528 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_BARLOW_RIDGE_HOST_40G_NHI) },
1529
1530 /* Any USB4 compliant host */
1531 { PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_USB_USB4, ~0) },
1532
1533 { 0,}
1534 };
1535
1536 MODULE_DEVICE_TABLE(pci, nhi_ids);
1537 MODULE_DESCRIPTION("Thunderbolt/USB4 core driver");
1538 MODULE_LICENSE("GPL");
1539
1540 static struct pci_driver nhi_driver = {
1541 .name = "thunderbolt",
1542 .id_table = nhi_ids,
1543 .probe = nhi_probe,
1544 .remove = nhi_remove,
1545 .shutdown = nhi_remove,
1546 .driver.pm = &nhi_pm_ops,
1547 };
1548
nhi_init(void)1549 static int __init nhi_init(void)
1550 {
1551 int ret;
1552
1553 ret = tb_domain_init();
1554 if (ret)
1555 return ret;
1556 ret = pci_register_driver(&nhi_driver);
1557 if (ret)
1558 tb_domain_exit();
1559 return ret;
1560 }
1561
nhi_unload(void)1562 static void __exit nhi_unload(void)
1563 {
1564 pci_unregister_driver(&nhi_driver);
1565 tb_domain_exit();
1566 }
1567
1568 rootfs_initcall(nhi_init);
1569 module_exit(nhi_unload);
1570