xref: /openbmc/linux/drivers/usb/host/xhci-mem.c (revision fd589a8f)
1 /*
2  * xHCI host controller driver
3  *
4  * Copyright (C) 2008 Intel Corp.
5  *
6  * Author: Sarah Sharp
7  * Some code borrowed from the Linux EHCI driver.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
16  * for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software Foundation,
20  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  */
22 
23 #include <linux/usb.h>
24 #include <linux/pci.h>
25 #include <linux/dmapool.h>
26 
27 #include "xhci.h"
28 
29 /*
30  * Allocates a generic ring segment from the ring pool, sets the dma address,
31  * initializes the segment to zero, and sets the private next pointer to NULL.
32  *
33  * Section 4.11.1.1:
34  * "All components of all Command and Transfer TRBs shall be initialized to '0'"
35  */
36 static struct xhci_segment *xhci_segment_alloc(struct xhci_hcd *xhci, gfp_t flags)
37 {
38 	struct xhci_segment *seg;
39 	dma_addr_t	dma;
40 
41 	seg = kzalloc(sizeof *seg, flags);
42 	if (!seg)
43 		return 0;
44 	xhci_dbg(xhci, "Allocating priv segment structure at %p\n", seg);
45 
46 	seg->trbs = dma_pool_alloc(xhci->segment_pool, flags, &dma);
47 	if (!seg->trbs) {
48 		kfree(seg);
49 		return 0;
50 	}
51 	xhci_dbg(xhci, "// Allocating segment at %p (virtual) 0x%llx (DMA)\n",
52 			seg->trbs, (unsigned long long)dma);
53 
54 	memset(seg->trbs, 0, SEGMENT_SIZE);
55 	seg->dma = dma;
56 	seg->next = NULL;
57 
58 	return seg;
59 }
60 
61 static void xhci_segment_free(struct xhci_hcd *xhci, struct xhci_segment *seg)
62 {
63 	if (!seg)
64 		return;
65 	if (seg->trbs) {
66 		xhci_dbg(xhci, "Freeing DMA segment at %p (virtual) 0x%llx (DMA)\n",
67 				seg->trbs, (unsigned long long)seg->dma);
68 		dma_pool_free(xhci->segment_pool, seg->trbs, seg->dma);
69 		seg->trbs = NULL;
70 	}
71 	xhci_dbg(xhci, "Freeing priv segment structure at %p\n", seg);
72 	kfree(seg);
73 }
74 
75 /*
76  * Make the prev segment point to the next segment.
77  *
78  * Change the last TRB in the prev segment to be a Link TRB which points to the
79  * DMA address of the next segment.  The caller needs to set any Link TRB
80  * related flags, such as End TRB, Toggle Cycle, and no snoop.
81  */
82 static void xhci_link_segments(struct xhci_hcd *xhci, struct xhci_segment *prev,
83 		struct xhci_segment *next, bool link_trbs)
84 {
85 	u32 val;
86 
87 	if (!prev || !next)
88 		return;
89 	prev->next = next;
90 	if (link_trbs) {
91 		prev->trbs[TRBS_PER_SEGMENT-1].link.segment_ptr = next->dma;
92 
93 		/* Set the last TRB in the segment to have a TRB type ID of Link TRB */
94 		val = prev->trbs[TRBS_PER_SEGMENT-1].link.control;
95 		val &= ~TRB_TYPE_BITMASK;
96 		val |= TRB_TYPE(TRB_LINK);
97 		prev->trbs[TRBS_PER_SEGMENT-1].link.control = val;
98 	}
99 	xhci_dbg(xhci, "Linking segment 0x%llx to segment 0x%llx (DMA)\n",
100 			(unsigned long long)prev->dma,
101 			(unsigned long long)next->dma);
102 }
103 
104 /* XXX: Do we need the hcd structure in all these functions? */
105 void xhci_ring_free(struct xhci_hcd *xhci, struct xhci_ring *ring)
106 {
107 	struct xhci_segment *seg;
108 	struct xhci_segment *first_seg;
109 
110 	if (!ring || !ring->first_seg)
111 		return;
112 	first_seg = ring->first_seg;
113 	seg = first_seg->next;
114 	xhci_dbg(xhci, "Freeing ring at %p\n", ring);
115 	while (seg != first_seg) {
116 		struct xhci_segment *next = seg->next;
117 		xhci_segment_free(xhci, seg);
118 		seg = next;
119 	}
120 	xhci_segment_free(xhci, first_seg);
121 	ring->first_seg = NULL;
122 	kfree(ring);
123 }
124 
125 /**
126  * Create a new ring with zero or more segments.
127  *
128  * Link each segment together into a ring.
129  * Set the end flag and the cycle toggle bit on the last segment.
130  * See section 4.9.1 and figures 15 and 16.
131  */
132 static struct xhci_ring *xhci_ring_alloc(struct xhci_hcd *xhci,
133 		unsigned int num_segs, bool link_trbs, gfp_t flags)
134 {
135 	struct xhci_ring	*ring;
136 	struct xhci_segment	*prev;
137 
138 	ring = kzalloc(sizeof *(ring), flags);
139 	xhci_dbg(xhci, "Allocating ring at %p\n", ring);
140 	if (!ring)
141 		return 0;
142 
143 	INIT_LIST_HEAD(&ring->td_list);
144 	INIT_LIST_HEAD(&ring->cancelled_td_list);
145 	if (num_segs == 0)
146 		return ring;
147 
148 	ring->first_seg = xhci_segment_alloc(xhci, flags);
149 	if (!ring->first_seg)
150 		goto fail;
151 	num_segs--;
152 
153 	prev = ring->first_seg;
154 	while (num_segs > 0) {
155 		struct xhci_segment	*next;
156 
157 		next = xhci_segment_alloc(xhci, flags);
158 		if (!next)
159 			goto fail;
160 		xhci_link_segments(xhci, prev, next, link_trbs);
161 
162 		prev = next;
163 		num_segs--;
164 	}
165 	xhci_link_segments(xhci, prev, ring->first_seg, link_trbs);
166 
167 	if (link_trbs) {
168 		/* See section 4.9.2.1 and 6.4.4.1 */
169 		prev->trbs[TRBS_PER_SEGMENT-1].link.control |= (LINK_TOGGLE);
170 		xhci_dbg(xhci, "Wrote link toggle flag to"
171 				" segment %p (virtual), 0x%llx (DMA)\n",
172 				prev, (unsigned long long)prev->dma);
173 	}
174 	/* The ring is empty, so the enqueue pointer == dequeue pointer */
175 	ring->enqueue = ring->first_seg->trbs;
176 	ring->enq_seg = ring->first_seg;
177 	ring->dequeue = ring->enqueue;
178 	ring->deq_seg = ring->first_seg;
179 	/* The ring is initialized to 0. The producer must write 1 to the cycle
180 	 * bit to handover ownership of the TRB, so PCS = 1.  The consumer must
181 	 * compare CCS to the cycle bit to check ownership, so CCS = 1.
182 	 */
183 	ring->cycle_state = 1;
184 
185 	return ring;
186 
187 fail:
188 	xhci_ring_free(xhci, ring);
189 	return 0;
190 }
191 
192 #define CTX_SIZE(_hcc) (HCC_64BYTE_CONTEXT(_hcc) ? 64 : 32)
193 
194 struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci,
195 						    int type, gfp_t flags)
196 {
197 	struct xhci_container_ctx *ctx = kzalloc(sizeof(*ctx), flags);
198 	if (!ctx)
199 		return NULL;
200 
201 	BUG_ON((type != XHCI_CTX_TYPE_DEVICE) && (type != XHCI_CTX_TYPE_INPUT));
202 	ctx->type = type;
203 	ctx->size = HCC_64BYTE_CONTEXT(xhci->hcc_params) ? 2048 : 1024;
204 	if (type == XHCI_CTX_TYPE_INPUT)
205 		ctx->size += CTX_SIZE(xhci->hcc_params);
206 
207 	ctx->bytes = dma_pool_alloc(xhci->device_pool, flags, &ctx->dma);
208 	memset(ctx->bytes, 0, ctx->size);
209 	return ctx;
210 }
211 
212 void xhci_free_container_ctx(struct xhci_hcd *xhci,
213 			     struct xhci_container_ctx *ctx)
214 {
215 	dma_pool_free(xhci->device_pool, ctx->bytes, ctx->dma);
216 	kfree(ctx);
217 }
218 
219 struct xhci_input_control_ctx *xhci_get_input_control_ctx(struct xhci_hcd *xhci,
220 					      struct xhci_container_ctx *ctx)
221 {
222 	BUG_ON(ctx->type != XHCI_CTX_TYPE_INPUT);
223 	return (struct xhci_input_control_ctx *)ctx->bytes;
224 }
225 
226 struct xhci_slot_ctx *xhci_get_slot_ctx(struct xhci_hcd *xhci,
227 					struct xhci_container_ctx *ctx)
228 {
229 	if (ctx->type == XHCI_CTX_TYPE_DEVICE)
230 		return (struct xhci_slot_ctx *)ctx->bytes;
231 
232 	return (struct xhci_slot_ctx *)
233 		(ctx->bytes + CTX_SIZE(xhci->hcc_params));
234 }
235 
236 struct xhci_ep_ctx *xhci_get_ep_ctx(struct xhci_hcd *xhci,
237 				    struct xhci_container_ctx *ctx,
238 				    unsigned int ep_index)
239 {
240 	/* increment ep index by offset of start of ep ctx array */
241 	ep_index++;
242 	if (ctx->type == XHCI_CTX_TYPE_INPUT)
243 		ep_index++;
244 
245 	return (struct xhci_ep_ctx *)
246 		(ctx->bytes + (ep_index * CTX_SIZE(xhci->hcc_params)));
247 }
248 
249 /* All the xhci_tds in the ring's TD list should be freed at this point */
250 void xhci_free_virt_device(struct xhci_hcd *xhci, int slot_id)
251 {
252 	struct xhci_virt_device *dev;
253 	int i;
254 
255 	/* Slot ID 0 is reserved */
256 	if (slot_id == 0 || !xhci->devs[slot_id])
257 		return;
258 
259 	dev = xhci->devs[slot_id];
260 	xhci->dcbaa->dev_context_ptrs[slot_id] = 0;
261 	if (!dev)
262 		return;
263 
264 	for (i = 0; i < 31; ++i)
265 		if (dev->ep_rings[i])
266 			xhci_ring_free(xhci, dev->ep_rings[i]);
267 
268 	if (dev->in_ctx)
269 		xhci_free_container_ctx(xhci, dev->in_ctx);
270 	if (dev->out_ctx)
271 		xhci_free_container_ctx(xhci, dev->out_ctx);
272 
273 	kfree(xhci->devs[slot_id]);
274 	xhci->devs[slot_id] = 0;
275 }
276 
277 int xhci_alloc_virt_device(struct xhci_hcd *xhci, int slot_id,
278 		struct usb_device *udev, gfp_t flags)
279 {
280 	struct xhci_virt_device *dev;
281 
282 	/* Slot ID 0 is reserved */
283 	if (slot_id == 0 || xhci->devs[slot_id]) {
284 		xhci_warn(xhci, "Bad Slot ID %d\n", slot_id);
285 		return 0;
286 	}
287 
288 	xhci->devs[slot_id] = kzalloc(sizeof(*xhci->devs[slot_id]), flags);
289 	if (!xhci->devs[slot_id])
290 		return 0;
291 	dev = xhci->devs[slot_id];
292 
293 	/* Allocate the (output) device context that will be used in the HC. */
294 	dev->out_ctx = xhci_alloc_container_ctx(xhci, XHCI_CTX_TYPE_DEVICE, flags);
295 	if (!dev->out_ctx)
296 		goto fail;
297 
298 	xhci_dbg(xhci, "Slot %d output ctx = 0x%llx (dma)\n", slot_id,
299 			(unsigned long long)dev->out_ctx->dma);
300 
301 	/* Allocate the (input) device context for address device command */
302 	dev->in_ctx = xhci_alloc_container_ctx(xhci, XHCI_CTX_TYPE_INPUT, flags);
303 	if (!dev->in_ctx)
304 		goto fail;
305 
306 	xhci_dbg(xhci, "Slot %d input ctx = 0x%llx (dma)\n", slot_id,
307 			(unsigned long long)dev->in_ctx->dma);
308 
309 	/* Allocate endpoint 0 ring */
310 	dev->ep_rings[0] = xhci_ring_alloc(xhci, 1, true, flags);
311 	if (!dev->ep_rings[0])
312 		goto fail;
313 
314 	init_completion(&dev->cmd_completion);
315 
316 	/* Point to output device context in dcbaa. */
317 	xhci->dcbaa->dev_context_ptrs[slot_id] = dev->out_ctx->dma;
318 	xhci_dbg(xhci, "Set slot id %d dcbaa entry %p to 0x%llx\n",
319 			slot_id,
320 			&xhci->dcbaa->dev_context_ptrs[slot_id],
321 			(unsigned long long) xhci->dcbaa->dev_context_ptrs[slot_id]);
322 
323 	return 1;
324 fail:
325 	xhci_free_virt_device(xhci, slot_id);
326 	return 0;
327 }
328 
329 /* Setup an xHCI virtual device for a Set Address command */
330 int xhci_setup_addressable_virt_dev(struct xhci_hcd *xhci, struct usb_device *udev)
331 {
332 	struct xhci_virt_device *dev;
333 	struct xhci_ep_ctx	*ep0_ctx;
334 	struct usb_device	*top_dev;
335 	struct xhci_slot_ctx    *slot_ctx;
336 	struct xhci_input_control_ctx *ctrl_ctx;
337 
338 	dev = xhci->devs[udev->slot_id];
339 	/* Slot ID 0 is reserved */
340 	if (udev->slot_id == 0 || !dev) {
341 		xhci_warn(xhci, "Slot ID %d is not assigned to this device\n",
342 				udev->slot_id);
343 		return -EINVAL;
344 	}
345 	ep0_ctx = xhci_get_ep_ctx(xhci, dev->in_ctx, 0);
346 	ctrl_ctx = xhci_get_input_control_ctx(xhci, dev->in_ctx);
347 	slot_ctx = xhci_get_slot_ctx(xhci, dev->in_ctx);
348 
349 	/* 2) New slot context and endpoint 0 context are valid*/
350 	ctrl_ctx->add_flags = SLOT_FLAG | EP0_FLAG;
351 
352 	/* 3) Only the control endpoint is valid - one endpoint context */
353 	slot_ctx->dev_info |= LAST_CTX(1);
354 
355 	switch (udev->speed) {
356 	case USB_SPEED_SUPER:
357 		slot_ctx->dev_info |= (u32) udev->route;
358 		slot_ctx->dev_info |= (u32) SLOT_SPEED_SS;
359 		break;
360 	case USB_SPEED_HIGH:
361 		slot_ctx->dev_info |= (u32) SLOT_SPEED_HS;
362 		break;
363 	case USB_SPEED_FULL:
364 		slot_ctx->dev_info |= (u32) SLOT_SPEED_FS;
365 		break;
366 	case USB_SPEED_LOW:
367 		slot_ctx->dev_info |= (u32) SLOT_SPEED_LS;
368 		break;
369 	case USB_SPEED_VARIABLE:
370 		xhci_dbg(xhci, "FIXME xHCI doesn't support wireless speeds\n");
371 		return -EINVAL;
372 		break;
373 	default:
374 		/* Speed was set earlier, this shouldn't happen. */
375 		BUG();
376 	}
377 	/* Find the root hub port this device is under */
378 	for (top_dev = udev; top_dev->parent && top_dev->parent->parent;
379 			top_dev = top_dev->parent)
380 		/* Found device below root hub */;
381 	slot_ctx->dev_info2 |= (u32) ROOT_HUB_PORT(top_dev->portnum);
382 	xhci_dbg(xhci, "Set root hub portnum to %d\n", top_dev->portnum);
383 
384 	/* Is this a LS/FS device under a HS hub? */
385 	/*
386 	 * FIXME: I don't think this is right, where does the TT info for the
387 	 * roothub or parent hub come from?
388 	 */
389 	if ((udev->speed == USB_SPEED_LOW || udev->speed == USB_SPEED_FULL) &&
390 			udev->tt) {
391 		slot_ctx->tt_info = udev->tt->hub->slot_id;
392 		slot_ctx->tt_info |= udev->ttport << 8;
393 	}
394 	xhci_dbg(xhci, "udev->tt = %p\n", udev->tt);
395 	xhci_dbg(xhci, "udev->ttport = 0x%x\n", udev->ttport);
396 
397 	/* Step 4 - ring already allocated */
398 	/* Step 5 */
399 	ep0_ctx->ep_info2 = EP_TYPE(CTRL_EP);
400 	/*
401 	 * See section 4.3 bullet 6:
402 	 * The default Max Packet size for ep0 is "8 bytes for a USB2
403 	 * LS/FS/HS device or 512 bytes for a USB3 SS device"
404 	 * XXX: Not sure about wireless USB devices.
405 	 */
406 	if (udev->speed == USB_SPEED_SUPER)
407 		ep0_ctx->ep_info2 |= MAX_PACKET(512);
408 	else
409 		ep0_ctx->ep_info2 |= MAX_PACKET(8);
410 	/* EP 0 can handle "burst" sizes of 1, so Max Burst Size field is 0 */
411 	ep0_ctx->ep_info2 |= MAX_BURST(0);
412 	ep0_ctx->ep_info2 |= ERROR_COUNT(3);
413 
414 	ep0_ctx->deq =
415 		dev->ep_rings[0]->first_seg->dma;
416 	ep0_ctx->deq |= dev->ep_rings[0]->cycle_state;
417 
418 	/* Steps 7 and 8 were done in xhci_alloc_virt_device() */
419 
420 	return 0;
421 }
422 
423 /* Return the polling or NAK interval.
424  *
425  * The polling interval is expressed in "microframes".  If xHCI's Interval field
426  * is set to N, it will service the endpoint every 2^(Interval)*125us.
427  *
428  * The NAK interval is one NAK per 1 to 255 microframes, or no NAKs if interval
429  * is set to 0.
430  */
431 static inline unsigned int xhci_get_endpoint_interval(struct usb_device *udev,
432 		struct usb_host_endpoint *ep)
433 {
434 	unsigned int interval = 0;
435 
436 	switch (udev->speed) {
437 	case USB_SPEED_HIGH:
438 		/* Max NAK rate */
439 		if (usb_endpoint_xfer_control(&ep->desc) ||
440 				usb_endpoint_xfer_bulk(&ep->desc))
441 			interval = ep->desc.bInterval;
442 		/* Fall through - SS and HS isoc/int have same decoding */
443 	case USB_SPEED_SUPER:
444 		if (usb_endpoint_xfer_int(&ep->desc) ||
445 				usb_endpoint_xfer_isoc(&ep->desc)) {
446 			if (ep->desc.bInterval == 0)
447 				interval = 0;
448 			else
449 				interval = ep->desc.bInterval - 1;
450 			if (interval > 15)
451 				interval = 15;
452 			if (interval != ep->desc.bInterval + 1)
453 				dev_warn(&udev->dev, "ep %#x - rounding interval to %d microframes\n",
454 						ep->desc.bEndpointAddress, 1 << interval);
455 		}
456 		break;
457 	/* Convert bInterval (in 1-255 frames) to microframes and round down to
458 	 * nearest power of 2.
459 	 */
460 	case USB_SPEED_FULL:
461 	case USB_SPEED_LOW:
462 		if (usb_endpoint_xfer_int(&ep->desc) ||
463 				usb_endpoint_xfer_isoc(&ep->desc)) {
464 			interval = fls(8*ep->desc.bInterval) - 1;
465 			if (interval > 10)
466 				interval = 10;
467 			if (interval < 3)
468 				interval = 3;
469 			if ((1 << interval) != 8*ep->desc.bInterval)
470 				dev_warn(&udev->dev, "ep %#x - rounding interval to %d microframes\n",
471 						ep->desc.bEndpointAddress, 1 << interval);
472 		}
473 		break;
474 	default:
475 		BUG();
476 	}
477 	return EP_INTERVAL(interval);
478 }
479 
480 static inline u32 xhci_get_endpoint_type(struct usb_device *udev,
481 		struct usb_host_endpoint *ep)
482 {
483 	int in;
484 	u32 type;
485 
486 	in = usb_endpoint_dir_in(&ep->desc);
487 	if (usb_endpoint_xfer_control(&ep->desc)) {
488 		type = EP_TYPE(CTRL_EP);
489 	} else if (usb_endpoint_xfer_bulk(&ep->desc)) {
490 		if (in)
491 			type = EP_TYPE(BULK_IN_EP);
492 		else
493 			type = EP_TYPE(BULK_OUT_EP);
494 	} else if (usb_endpoint_xfer_isoc(&ep->desc)) {
495 		if (in)
496 			type = EP_TYPE(ISOC_IN_EP);
497 		else
498 			type = EP_TYPE(ISOC_OUT_EP);
499 	} else if (usb_endpoint_xfer_int(&ep->desc)) {
500 		if (in)
501 			type = EP_TYPE(INT_IN_EP);
502 		else
503 			type = EP_TYPE(INT_OUT_EP);
504 	} else {
505 		BUG();
506 	}
507 	return type;
508 }
509 
510 int xhci_endpoint_init(struct xhci_hcd *xhci,
511 		struct xhci_virt_device *virt_dev,
512 		struct usb_device *udev,
513 		struct usb_host_endpoint *ep,
514 		gfp_t mem_flags)
515 {
516 	unsigned int ep_index;
517 	struct xhci_ep_ctx *ep_ctx;
518 	struct xhci_ring *ep_ring;
519 	unsigned int max_packet;
520 	unsigned int max_burst;
521 
522 	ep_index = xhci_get_endpoint_index(&ep->desc);
523 	ep_ctx = xhci_get_ep_ctx(xhci, virt_dev->in_ctx, ep_index);
524 
525 	/* Set up the endpoint ring */
526 	virt_dev->new_ep_rings[ep_index] = xhci_ring_alloc(xhci, 1, true, mem_flags);
527 	if (!virt_dev->new_ep_rings[ep_index])
528 		return -ENOMEM;
529 	ep_ring = virt_dev->new_ep_rings[ep_index];
530 	ep_ctx->deq = ep_ring->first_seg->dma | ep_ring->cycle_state;
531 
532 	ep_ctx->ep_info = xhci_get_endpoint_interval(udev, ep);
533 
534 	/* FIXME dig Mult and streams info out of ep companion desc */
535 
536 	/* Allow 3 retries for everything but isoc;
537 	 * error count = 0 means infinite retries.
538 	 */
539 	if (!usb_endpoint_xfer_isoc(&ep->desc))
540 		ep_ctx->ep_info2 = ERROR_COUNT(3);
541 	else
542 		ep_ctx->ep_info2 = ERROR_COUNT(1);
543 
544 	ep_ctx->ep_info2 |= xhci_get_endpoint_type(udev, ep);
545 
546 	/* Set the max packet size and max burst */
547 	switch (udev->speed) {
548 	case USB_SPEED_SUPER:
549 		max_packet = ep->desc.wMaxPacketSize;
550 		ep_ctx->ep_info2 |= MAX_PACKET(max_packet);
551 		/* dig out max burst from ep companion desc */
552 		if (!ep->ss_ep_comp) {
553 			xhci_warn(xhci, "WARN no SS endpoint companion descriptor.\n");
554 			max_packet = 0;
555 		} else {
556 			max_packet = ep->ss_ep_comp->desc.bMaxBurst;
557 		}
558 		ep_ctx->ep_info2 |= MAX_BURST(max_packet);
559 		break;
560 	case USB_SPEED_HIGH:
561 		/* bits 11:12 specify the number of additional transaction
562 		 * opportunities per microframe (USB 2.0, section 9.6.6)
563 		 */
564 		if (usb_endpoint_xfer_isoc(&ep->desc) ||
565 				usb_endpoint_xfer_int(&ep->desc)) {
566 			max_burst = (ep->desc.wMaxPacketSize & 0x1800) >> 11;
567 			ep_ctx->ep_info2 |= MAX_BURST(max_burst);
568 		}
569 		/* Fall through */
570 	case USB_SPEED_FULL:
571 	case USB_SPEED_LOW:
572 		max_packet = ep->desc.wMaxPacketSize & 0x3ff;
573 		ep_ctx->ep_info2 |= MAX_PACKET(max_packet);
574 		break;
575 	default:
576 		BUG();
577 	}
578 	/* FIXME Debug endpoint context */
579 	return 0;
580 }
581 
582 void xhci_endpoint_zero(struct xhci_hcd *xhci,
583 		struct xhci_virt_device *virt_dev,
584 		struct usb_host_endpoint *ep)
585 {
586 	unsigned int ep_index;
587 	struct xhci_ep_ctx *ep_ctx;
588 
589 	ep_index = xhci_get_endpoint_index(&ep->desc);
590 	ep_ctx = xhci_get_ep_ctx(xhci, virt_dev->in_ctx, ep_index);
591 
592 	ep_ctx->ep_info = 0;
593 	ep_ctx->ep_info2 = 0;
594 	ep_ctx->deq = 0;
595 	ep_ctx->tx_info = 0;
596 	/* Don't free the endpoint ring until the set interface or configuration
597 	 * request succeeds.
598 	 */
599 }
600 
601 /* Set up the scratchpad buffer array and scratchpad buffers, if needed. */
602 static int scratchpad_alloc(struct xhci_hcd *xhci, gfp_t flags)
603 {
604 	int i;
605 	struct device *dev = xhci_to_hcd(xhci)->self.controller;
606 	int num_sp = HCS_MAX_SCRATCHPAD(xhci->hcs_params2);
607 
608 	xhci_dbg(xhci, "Allocating %d scratchpad buffers\n", num_sp);
609 
610 	if (!num_sp)
611 		return 0;
612 
613 	xhci->scratchpad = kzalloc(sizeof(*xhci->scratchpad), flags);
614 	if (!xhci->scratchpad)
615 		goto fail_sp;
616 
617 	xhci->scratchpad->sp_array =
618 		pci_alloc_consistent(to_pci_dev(dev),
619 				     num_sp * sizeof(u64),
620 				     &xhci->scratchpad->sp_dma);
621 	if (!xhci->scratchpad->sp_array)
622 		goto fail_sp2;
623 
624 	xhci->scratchpad->sp_buffers = kzalloc(sizeof(void *) * num_sp, flags);
625 	if (!xhci->scratchpad->sp_buffers)
626 		goto fail_sp3;
627 
628 	xhci->scratchpad->sp_dma_buffers =
629 		kzalloc(sizeof(dma_addr_t) * num_sp, flags);
630 
631 	if (!xhci->scratchpad->sp_dma_buffers)
632 		goto fail_sp4;
633 
634 	xhci->dcbaa->dev_context_ptrs[0] = xhci->scratchpad->sp_dma;
635 	for (i = 0; i < num_sp; i++) {
636 		dma_addr_t dma;
637 		void *buf = pci_alloc_consistent(to_pci_dev(dev),
638 						 xhci->page_size, &dma);
639 		if (!buf)
640 			goto fail_sp5;
641 
642 		xhci->scratchpad->sp_array[i] = dma;
643 		xhci->scratchpad->sp_buffers[i] = buf;
644 		xhci->scratchpad->sp_dma_buffers[i] = dma;
645 	}
646 
647 	return 0;
648 
649  fail_sp5:
650 	for (i = i - 1; i >= 0; i--) {
651 		pci_free_consistent(to_pci_dev(dev), xhci->page_size,
652 				    xhci->scratchpad->sp_buffers[i],
653 				    xhci->scratchpad->sp_dma_buffers[i]);
654 	}
655 	kfree(xhci->scratchpad->sp_dma_buffers);
656 
657  fail_sp4:
658 	kfree(xhci->scratchpad->sp_buffers);
659 
660  fail_sp3:
661 	pci_free_consistent(to_pci_dev(dev), num_sp * sizeof(u64),
662 			    xhci->scratchpad->sp_array,
663 			    xhci->scratchpad->sp_dma);
664 
665  fail_sp2:
666 	kfree(xhci->scratchpad);
667 	xhci->scratchpad = NULL;
668 
669  fail_sp:
670 	return -ENOMEM;
671 }
672 
673 static void scratchpad_free(struct xhci_hcd *xhci)
674 {
675 	int num_sp;
676 	int i;
677 	struct pci_dev	*pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);
678 
679 	if (!xhci->scratchpad)
680 		return;
681 
682 	num_sp = HCS_MAX_SCRATCHPAD(xhci->hcs_params2);
683 
684 	for (i = 0; i < num_sp; i++) {
685 		pci_free_consistent(pdev, xhci->page_size,
686 				    xhci->scratchpad->sp_buffers[i],
687 				    xhci->scratchpad->sp_dma_buffers[i]);
688 	}
689 	kfree(xhci->scratchpad->sp_dma_buffers);
690 	kfree(xhci->scratchpad->sp_buffers);
691 	pci_free_consistent(pdev, num_sp * sizeof(u64),
692 			    xhci->scratchpad->sp_array,
693 			    xhci->scratchpad->sp_dma);
694 	kfree(xhci->scratchpad);
695 	xhci->scratchpad = NULL;
696 }
697 
698 void xhci_mem_cleanup(struct xhci_hcd *xhci)
699 {
700 	struct pci_dev	*pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);
701 	int size;
702 	int i;
703 
704 	/* Free the Event Ring Segment Table and the actual Event Ring */
705 	xhci_writel(xhci, 0, &xhci->ir_set->erst_size);
706 	xhci_write_64(xhci, 0, &xhci->ir_set->erst_base);
707 	xhci_write_64(xhci, 0, &xhci->ir_set->erst_dequeue);
708 	size = sizeof(struct xhci_erst_entry)*(xhci->erst.num_entries);
709 	if (xhci->erst.entries)
710 		pci_free_consistent(pdev, size,
711 				xhci->erst.entries, xhci->erst.erst_dma_addr);
712 	xhci->erst.entries = NULL;
713 	xhci_dbg(xhci, "Freed ERST\n");
714 	if (xhci->event_ring)
715 		xhci_ring_free(xhci, xhci->event_ring);
716 	xhci->event_ring = NULL;
717 	xhci_dbg(xhci, "Freed event ring\n");
718 
719 	xhci_write_64(xhci, 0, &xhci->op_regs->cmd_ring);
720 	if (xhci->cmd_ring)
721 		xhci_ring_free(xhci, xhci->cmd_ring);
722 	xhci->cmd_ring = NULL;
723 	xhci_dbg(xhci, "Freed command ring\n");
724 
725 	for (i = 1; i < MAX_HC_SLOTS; ++i)
726 		xhci_free_virt_device(xhci, i);
727 
728 	if (xhci->segment_pool)
729 		dma_pool_destroy(xhci->segment_pool);
730 	xhci->segment_pool = NULL;
731 	xhci_dbg(xhci, "Freed segment pool\n");
732 
733 	if (xhci->device_pool)
734 		dma_pool_destroy(xhci->device_pool);
735 	xhci->device_pool = NULL;
736 	xhci_dbg(xhci, "Freed device context pool\n");
737 
738 	xhci_write_64(xhci, 0, &xhci->op_regs->dcbaa_ptr);
739 	if (xhci->dcbaa)
740 		pci_free_consistent(pdev, sizeof(*xhci->dcbaa),
741 				xhci->dcbaa, xhci->dcbaa->dma);
742 	xhci->dcbaa = NULL;
743 
744 	xhci->page_size = 0;
745 	xhci->page_shift = 0;
746 	scratchpad_free(xhci);
747 }
748 
749 int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
750 {
751 	dma_addr_t	dma;
752 	struct device	*dev = xhci_to_hcd(xhci)->self.controller;
753 	unsigned int	val, val2;
754 	u64		val_64;
755 	struct xhci_segment	*seg;
756 	u32 page_size;
757 	int i;
758 
759 	page_size = xhci_readl(xhci, &xhci->op_regs->page_size);
760 	xhci_dbg(xhci, "Supported page size register = 0x%x\n", page_size);
761 	for (i = 0; i < 16; i++) {
762 		if ((0x1 & page_size) != 0)
763 			break;
764 		page_size = page_size >> 1;
765 	}
766 	if (i < 16)
767 		xhci_dbg(xhci, "Supported page size of %iK\n", (1 << (i+12)) / 1024);
768 	else
769 		xhci_warn(xhci, "WARN: no supported page size\n");
770 	/* Use 4K pages, since that's common and the minimum the HC supports */
771 	xhci->page_shift = 12;
772 	xhci->page_size = 1 << xhci->page_shift;
773 	xhci_dbg(xhci, "HCD page size set to %iK\n", xhci->page_size / 1024);
774 
775 	/*
776 	 * Program the Number of Device Slots Enabled field in the CONFIG
777 	 * register with the max value of slots the HC can handle.
778 	 */
779 	val = HCS_MAX_SLOTS(xhci_readl(xhci, &xhci->cap_regs->hcs_params1));
780 	xhci_dbg(xhci, "// xHC can handle at most %d device slots.\n",
781 			(unsigned int) val);
782 	val2 = xhci_readl(xhci, &xhci->op_regs->config_reg);
783 	val |= (val2 & ~HCS_SLOTS_MASK);
784 	xhci_dbg(xhci, "// Setting Max device slots reg = 0x%x.\n",
785 			(unsigned int) val);
786 	xhci_writel(xhci, val, &xhci->op_regs->config_reg);
787 
788 	/*
789 	 * Section 5.4.8 - doorbell array must be
790 	 * "physically contiguous and 64-byte (cache line) aligned".
791 	 */
792 	xhci->dcbaa = pci_alloc_consistent(to_pci_dev(dev),
793 			sizeof(*xhci->dcbaa), &dma);
794 	if (!xhci->dcbaa)
795 		goto fail;
796 	memset(xhci->dcbaa, 0, sizeof *(xhci->dcbaa));
797 	xhci->dcbaa->dma = dma;
798 	xhci_dbg(xhci, "// Device context base array address = 0x%llx (DMA), %p (virt)\n",
799 			(unsigned long long)xhci->dcbaa->dma, xhci->dcbaa);
800 	xhci_write_64(xhci, dma, &xhci->op_regs->dcbaa_ptr);
801 
802 	/*
803 	 * Initialize the ring segment pool.  The ring must be a contiguous
804 	 * structure comprised of TRBs.  The TRBs must be 16 byte aligned,
805 	 * however, the command ring segment needs 64-byte aligned segments,
806 	 * so we pick the greater alignment need.
807 	 */
808 	xhci->segment_pool = dma_pool_create("xHCI ring segments", dev,
809 			SEGMENT_SIZE, 64, xhci->page_size);
810 
811 	/* See Table 46 and Note on Figure 55 */
812 	xhci->device_pool = dma_pool_create("xHCI input/output contexts", dev,
813 			2112, 64, xhci->page_size);
814 	if (!xhci->segment_pool || !xhci->device_pool)
815 		goto fail;
816 
817 	/* Set up the command ring to have one segments for now. */
818 	xhci->cmd_ring = xhci_ring_alloc(xhci, 1, true, flags);
819 	if (!xhci->cmd_ring)
820 		goto fail;
821 	xhci_dbg(xhci, "Allocated command ring at %p\n", xhci->cmd_ring);
822 	xhci_dbg(xhci, "First segment DMA is 0x%llx\n",
823 			(unsigned long long)xhci->cmd_ring->first_seg->dma);
824 
825 	/* Set the address in the Command Ring Control register */
826 	val_64 = xhci_read_64(xhci, &xhci->op_regs->cmd_ring);
827 	val_64 = (val_64 & (u64) CMD_RING_RSVD_BITS) |
828 		(xhci->cmd_ring->first_seg->dma & (u64) ~CMD_RING_RSVD_BITS) |
829 		xhci->cmd_ring->cycle_state;
830 	xhci_dbg(xhci, "// Setting command ring address to 0x%x\n", val);
831 	xhci_write_64(xhci, val_64, &xhci->op_regs->cmd_ring);
832 	xhci_dbg_cmd_ptrs(xhci);
833 
834 	val = xhci_readl(xhci, &xhci->cap_regs->db_off);
835 	val &= DBOFF_MASK;
836 	xhci_dbg(xhci, "// Doorbell array is located at offset 0x%x"
837 			" from cap regs base addr\n", val);
838 	xhci->dba = (void *) xhci->cap_regs + val;
839 	xhci_dbg_regs(xhci);
840 	xhci_print_run_regs(xhci);
841 	/* Set ir_set to interrupt register set 0 */
842 	xhci->ir_set = (void *) xhci->run_regs->ir_set;
843 
844 	/*
845 	 * Event ring setup: Allocate a normal ring, but also setup
846 	 * the event ring segment table (ERST).  Section 4.9.3.
847 	 */
848 	xhci_dbg(xhci, "// Allocating event ring\n");
849 	xhci->event_ring = xhci_ring_alloc(xhci, ERST_NUM_SEGS, false, flags);
850 	if (!xhci->event_ring)
851 		goto fail;
852 
853 	xhci->erst.entries = pci_alloc_consistent(to_pci_dev(dev),
854 			sizeof(struct xhci_erst_entry)*ERST_NUM_SEGS, &dma);
855 	if (!xhci->erst.entries)
856 		goto fail;
857 	xhci_dbg(xhci, "// Allocated event ring segment table at 0x%llx\n",
858 			(unsigned long long)dma);
859 
860 	memset(xhci->erst.entries, 0, sizeof(struct xhci_erst_entry)*ERST_NUM_SEGS);
861 	xhci->erst.num_entries = ERST_NUM_SEGS;
862 	xhci->erst.erst_dma_addr = dma;
863 	xhci_dbg(xhci, "Set ERST to 0; private num segs = %i, virt addr = %p, dma addr = 0x%llx\n",
864 			xhci->erst.num_entries,
865 			xhci->erst.entries,
866 			(unsigned long long)xhci->erst.erst_dma_addr);
867 
868 	/* set ring base address and size for each segment table entry */
869 	for (val = 0, seg = xhci->event_ring->first_seg; val < ERST_NUM_SEGS; val++) {
870 		struct xhci_erst_entry *entry = &xhci->erst.entries[val];
871 		entry->seg_addr = seg->dma;
872 		entry->seg_size = TRBS_PER_SEGMENT;
873 		entry->rsvd = 0;
874 		seg = seg->next;
875 	}
876 
877 	/* set ERST count with the number of entries in the segment table */
878 	val = xhci_readl(xhci, &xhci->ir_set->erst_size);
879 	val &= ERST_SIZE_MASK;
880 	val |= ERST_NUM_SEGS;
881 	xhci_dbg(xhci, "// Write ERST size = %i to ir_set 0 (some bits preserved)\n",
882 			val);
883 	xhci_writel(xhci, val, &xhci->ir_set->erst_size);
884 
885 	xhci_dbg(xhci, "// Set ERST entries to point to event ring.\n");
886 	/* set the segment table base address */
887 	xhci_dbg(xhci, "// Set ERST base address for ir_set 0 = 0x%llx\n",
888 			(unsigned long long)xhci->erst.erst_dma_addr);
889 	val_64 = xhci_read_64(xhci, &xhci->ir_set->erst_base);
890 	val_64 &= ERST_PTR_MASK;
891 	val_64 |= (xhci->erst.erst_dma_addr & (u64) ~ERST_PTR_MASK);
892 	xhci_write_64(xhci, val_64, &xhci->ir_set->erst_base);
893 
894 	/* Set the event ring dequeue address */
895 	xhci_set_hc_event_deq(xhci);
896 	xhci_dbg(xhci, "Wrote ERST address to ir_set 0.\n");
897 	xhci_print_ir_set(xhci, xhci->ir_set, 0);
898 
899 	/*
900 	 * XXX: Might need to set the Interrupter Moderation Register to
901 	 * something other than the default (~1ms minimum between interrupts).
902 	 * See section 5.5.1.2.
903 	 */
904 	init_completion(&xhci->addr_dev);
905 	for (i = 0; i < MAX_HC_SLOTS; ++i)
906 		xhci->devs[i] = 0;
907 
908 	if (scratchpad_alloc(xhci, flags))
909 		goto fail;
910 
911 	return 0;
912 
913 fail:
914 	xhci_warn(xhci, "Couldn't initialize memory\n");
915 	xhci_mem_cleanup(xhci);
916 	return -ENOMEM;
917 }
918