summaryrefslogtreecommitdiffstats
path: root/drivers/usb/host/uhci-hcd.h
blob: e46d2b0203cb94cfcf6b569f446f279de0f16062 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
#ifndef __LINUX_UHCI_HCD_H
#define __LINUX_UHCI_HCD_H

#include <linux/list.h>
#include <linux/usb.h>

#define usb_packetid(pipe)	(usb_pipein(pipe) ? USB_PID_IN : USB_PID_OUT)
#define PIPE_DEVEP_MASK		0x0007ff00


/*
 * Universal Host Controller Interface data structures and defines
 */

/* Command register */
#define USBCMD		0
#define   USBCMD_RS		0x0001	/* Run/Stop */
#define   USBCMD_HCRESET	0x0002	/* Host reset */
#define   USBCMD_GRESET		0x0004	/* Global reset */
#define   USBCMD_EGSM		0x0008	/* Global Suspend Mode */
#define   USBCMD_FGR		0x0010	/* Force Global Resume */
#define   USBCMD_SWDBG		0x0020	/* SW Debug mode */
#define   USBCMD_CF		0x0040	/* Config Flag (sw only) */
#define   USBCMD_MAXP		0x0080	/* Max Packet (0 = 32, 1 = 64) */

/* Status register */
#define USBSTS		2
#define   USBSTS_USBINT		0x0001	/* Interrupt due to IOC */
#define   USBSTS_ERROR		0x0002	/* Interrupt due to error */
#define   USBSTS_RD		0x0004	/* Resume Detect */
#define   USBSTS_HSE		0x0008	/* Host System Error: PCI problems */
#define   USBSTS_HCPE		0x0010	/* Host Controller Process Error:
					 * the schedule is buggy */
#define   USBSTS_HCH		0x0020	/* HC Halted */

/* Interrupt enable register */
#define USBINTR		4
#define   USBINTR_TIMEOUT	0x0001	/* Timeout/CRC error enable */
#define   USBINTR_RESUME	0x0002	/* Resume interrupt enable */
#define   USBINTR_IOC		0x0004	/* Interrupt On Complete enable */
#define   USBINTR_SP		0x0008	/* Short packet interrupt enable */

#define USBFRNUM	6
#define USBFLBASEADD	8
#define USBSOF		12
#define   USBSOF_DEFAULT	64	/* Frame length is exactly 1 ms */

/* USB port status and control registers */
#define USBPORTSC1	16
#define USBPORTSC2	18
#define   USBPORTSC_CCS		0x0001	/* Current Connect Status
					 * ("device present") */
#define   USBPORTSC_CSC		0x0002	/* Connect Status Change */
#define   USBPORTSC_PE		0x0004	/* Port Enable */
#define   USBPORTSC_PEC		0x0008	/* Port Enable Change */
#define   USBPORTSC_DPLUS	0x0010	/* D+ high (line status) */
#define   USBPORTSC_DMINUS	0x0020	/* D- high (line status) */
#define   USBPORTSC_RD		0x0040	/* Resume Detect */
#define   USBPORTSC_RES1	0x0080	/* reserved, always 1 */
#define   USBPORTSC_LSDA	0x0100	/* Low Speed Device Attached */
#define   USBPORTSC_PR		0x0200	/* Port Reset */
/* OC and OCC from Intel 430TX and later (not UHCI 1.1d spec) */
#define   USBPORTSC_OC		0x0400	/* Over Current condition */
#define   USBPORTSC_OCC		0x0800	/* Over Current Change R/WC */
#define   USBPORTSC_SUSP	0x1000	/* Suspend */
#define   USBPORTSC_RES2	0x2000	/* reserved, write zeroes */
#define   USBPORTSC_RES3	0x4000	/* reserved, write zeroes */
#define   USBPORTSC_RES4	0x8000	/* reserved, write zeroes */

/* Legacy support register */
#define USBLEGSUP		0xc0
#define   USBLEGSUP_DEFAULT	0x2000	/* only PIRQ enable set */
#define   USBLEGSUP_RWC		0x8f00	/* the R/WC bits */
#define   USBLEGSUP_RO		0x5040	/* R/O and reserved bits */

#define UHCI_PTR_BITS		__constant_cpu_to_le32(0x000F)
#define UHCI_PTR_TERM		__constant_cpu_to_le32(0x0001)
#define UHCI_PTR_QH		__constant_cpu_to_le32(0x0002)
#define UHCI_PTR_DEPTH		__constant_cpu_to_le32(0x0004)
#define UHCI_PTR_BREADTH	__constant_cpu_to_le32(0x0000)

#define UHCI_NUMFRAMES		1024	/* in the frame list [array] */
#define UHCI_MAX_SOF_NUMBER	2047	/* in an SOF packet */
#define CAN_SCHEDULE_FRAMES	1000	/* how far in the future frames
					 * can be scheduled */
#define MAX_PHASE		32	/* Periodic scheduling length */

/* When no queues need Full-Speed Bandwidth Reclamation,
 * delay this long before turning FSBR off */
#define FSBR_OFF_DELAY		msecs_to_jiffies(10)

/* If a queue hasn't advanced after this much time, assume it is stuck */
#define QH_WAIT_TIMEOUT		msecs_to_jiffies(200)


/*
 *	Queue Headers
 */

/*
 * One role of a QH is to hold a queue of TDs for some endpoint.  One QH goes
 * with each endpoint, and qh->element (updated by the HC) is either:
 *   - the next unprocessed TD in the endpoint's queue, or
 *   - UHCI_PTR_TERM (when there's no more traffic for this endpoint).
 *
 * The other role of a QH is to serve as a "skeleton" framelist entry, so we
 * can easily splice a QH for some endpoint into the schedule at the right
 * place.  Then qh->element is UHCI_PTR_TERM.
 *
 * In the schedule, qh->link maintains a list of QHs seen by the HC:
 *     skel1 --> ep1-qh --> ep2-qh --> ... --> skel2 --> ...
 *
 * qh->node is the software equivalent of qh->link.  The differences
 * are that the software list is doubly-linked and QHs in the UNLINKING
 * state are on the software list but not the hardware schedule.
 *
 * For bookkeeping purposes we maintain QHs even for Isochronous endpoints,
 * but they never get added to the hardware schedule.
 */
#define QH_STATE_IDLE		1	/* QH is not being used */
#define QH_STATE_UNLINKING	2	/* QH has been removed from the
					 * schedule but the hardware may
					 * still be using it */
#define QH_STATE_ACTIVE		3	/* QH is on the schedule */

struct uhci_qh {
	/* Hardware fields */
	__le32 link;			/* Next QH in the schedule */
	__le32 element;			/* Queue element (TD) pointer */

	/* Software fields */
	dma_addr_t dma_handle;

	struct list_head node;		/* Node in the list of QHs */
	struct usb_host_endpoint *hep;	/* Endpoint information */
	struct usb_device *udev;
	struct list_head queue;		/* Queue of urbps for this QH */
	struct uhci_td *dummy_td;	/* Dummy TD to end the queue */
	struct uhci_td *post_td;	/* Last TD completed */

	struct usb_iso_packet_descriptor *iso_packet_desc;
					/* Next urb->iso_frame_desc entry */
	unsigned long advance_jiffies;	/* Time of last queue advance */
	unsigned int unlink_frame;	/* When the QH was unlinked */
	unsigned int period;		/* For Interrupt and Isochronous QHs */
	short phase;			/* Between 0 and period-1 */
	short load;			/* Periodic time requirement, in us */
	unsigned int iso_frame;		/* Frame # for iso_packet_desc */

	int state;			/* QH_STATE_xxx; see above */
	int type;			/* Queue type (control, bulk, etc) */
	int skel;			/* Skeleton queue number */

	unsigned int initial_toggle:1;	/* Endpoint's current toggle value */
	unsigned int needs_fixup:1;	/* Must fix the TD toggle values */
	unsigned int is_stopped:1;	/* Queue was stopped by error/unlink */
	unsigned int wait_expired:1;	/* QH_WAIT_TIMEOUT has expired */
	unsigned int bandwidth_reserved:1;	/* Periodic bandwidth has
						 * been allocated */
} __attribute__((aligned(16)));

/*
 * We need a special accessor for the element pointer because it is
 * subject to asynchronous updates by the controller.
 */
static inline __le32 qh_element(struct uhci_qh *qh) {
	__le32 element = qh->element;

	barrier();
	return element;
}

#define LINK_TO_QH(qh)		(UHCI_PTR_QH | cpu_to_le32((qh)->dma_handle))


/*
 *	Transfer Descriptors
 */

/*
 * for TD <status>:
 */
#define TD_CTRL_SPD		(1 << 29)	/* Short Packet Detect */
#define TD_CTRL_C_ERR_MASK	(3 << 27)	/* Error Counter bits */
#define TD_CTRL_C_ERR_SHIFT	27
#define TD_CTRL_LS		(1 << 26)	/* Low Speed Device */
#define TD_CTRL_IOS		(1 << 25)	/* Isochronous Select */
#define TD_CTRL_IOC		(1 << 24)	/* Interrupt on Complete */
#define TD_CTRL_ACTIVE		(1 << 23)	/* TD Active */
#define TD_CTRL_STALLED		(1 << 22)	/* TD Stalled */
#define TD_CTRL_DBUFERR		(1 << 21)	/* Data Buffer Error */
#define TD_CTRL_BABBLE		(1 << 20)	/* Babble Detected */
#define TD_CTRL_NAK		(1 << 19)	/* NAK Received */
#define TD_CTRL_CRCTIMEO	(1 << 18)	/* CRC/Time Out Error */
#define TD_CTRL_BITSTUFF	(1 << 17)	/* Bit Stuff Error */
#define TD_CTRL_ACTLEN_MASK	0x7FF	/* actual length, encoded as n - 1 */

#define TD_CTRL_ANY_ERROR	(TD_CTRL_STALLED | TD_CTRL_DBUFERR | \
				 TD_CTRL_BABBLE | TD_CTRL_CRCTIME | \
				 TD_CTRL_BITSTUFF)

#define uhci_maxerr(err)		((err) << TD_CTRL_C_ERR_SHIFT)
#define uhci_status_bits(ctrl_sts)	((ctrl_sts) & 0xF60000)
#define uhci_actual_length(ctrl_sts)	(((ctrl_sts) + 1) & \
			TD_CTRL_ACTLEN_MASK)	/* 1-based */

/*
 * for TD <info>: (a.k.a. Token)
 */
#define td_token(td)		le32_to_cpu((td)->token)
#define TD_TOKEN_DEVADDR_SHIFT	8
#define TD_TOKEN_TOGGLE_SHIFT	19
#define TD_TOKEN_TOGGLE		(1 << 19)
#define TD_TOKEN_EXPLEN_SHIFT	21
#define TD_TOKEN_EXPLEN_MASK	0x7FF	/* expected length, encoded as n-1 */
#define TD_TOKEN_PID_MASK	0xFF

#define uhci_explen(len)	((((len) - 1) & TD_TOKEN_EXPLEN_MASK) << \
					TD_TOKEN_EXPLEN_SHIFT)

#define uhci_expected_length(token) ((((token) >> TD_TOKEN_EXPLEN_SHIFT) + \
					1) & TD_TOKEN_EXPLEN_MASK)
#define uhci_toggle(token)	(((token) >> TD_TOKEN_TOGGLE_SHIFT) & 1)
#define uhci_endpoint(token)	(((token) >> 15) & 0xf)
#define uhci_devaddr(token)	(((token) >> TD_TOKEN_DEVADDR_SHIFT) & 0x7f)
#define uhci_devep(token)	(((token) >> TD_TOKEN_DEVADDR_SHIFT) & 0x7ff)
#define uhci_packetid(token)	((token) & TD_TOKEN_PID_MASK)
#define uhci_packetout(token)	(uhci_packetid(token) != USB_PID_IN)
#define uhci_packetin(token)	(uhci_packetid(token) == USB_PID_IN)

/*
 * The documentation says "4 words for hardware, 4 words for software".
 *
 * That's silly, the hardware doesn't care. The hardware only cares that
 * the hardware words are 16-byte aligned, and we can have any amount of
 * sw space after the TD entry.
 *
 * td->link points to either another TD (not necessarily for the same urb or
 * even the same endpoint), or nothing (PTR_TERM), or a QH.
 */
struct uhci_td {
	/* Hardware fields */
	__le32 link;
	__le32 status;
	__le32 token;
	__le32 buffer;

	/* Software fields */
	dma_addr_t dma_handle;

	struct list_head list;

	int frame;			/* for iso: what frame? */
	struct list_head fl_list;
} __attribute__((aligned(16)));

/*
 * We need a special accessor for the control/status word because it is
 * subject to asynchronous updates by the controller.
 */
static inline u32 td_status(struct uhci_td *td) {
	__le32 status = td->status;

	barrier();
	return le32_to_cpu(status);
}

#define LINK_TO_TD(td)		(cpu_to_le32((td)->dma_handle))


/*
 *	Skeleton Queue Headers
 */

/*
 * The UHCI driver uses QHs with Interrupt, Control and Bulk URBs for
 * automatic queuing. To make it easy to insert entries into the schedule,
 * we have a skeleton of QHs for each predefined Interrupt latency.
 * Asynchronous QHs (low-speed control, full-speed control, and bulk)
 * go onto the period-1 interrupt list, since they all get accessed on
 * every frame.
 *
 * When we want to add a new QH, we add it to the list starting from the
 * appropriate skeleton QH.  For instance, the schedule can look like this:
 *
 * skel int128 QH
 * dev 1 interrupt QH
 * dev 5 interrupt QH
 * skel int64 QH
 * skel int32 QH
 * ...
 * skel int1 + async QH
 * dev 5 low-speed control QH
 * dev 1 bulk QH
 * dev 2 bulk QH
 *
 * There is a special terminating QH used to keep full-speed bandwidth
 * reclamation active when no full-speed control or bulk QHs are linked
 * into the schedule.  It has an inactive TD (to work around a PIIX bug,
 * see the Intel errata) and it points back to itself.
 *
 * There's a special skeleton QH for Isochronous QHs which never appears
 * on the schedule.  Isochronous TDs go on the schedule before the
 * the skeleton QHs.  The hardware accesses them directly rather than
 * through their QH, which is used only for bookkeeping purposes.
 * While the UHCI spec doesn't forbid the use of QHs for Isochronous,
 * it doesn't use them either.  And the spec says that queues never
 * advance on an error completion status, which makes them totally
 * unsuitable for Isochronous transfers.
 *
 * There's also a special skeleton QH used for QHs which are in the process
 * of unlinking and so may still be in use by the hardware.  It too never
 * appears on the schedule.
 */

#define UHCI_NUM_SKELQH		11
#define SKEL_UNLINK		0
#define skel_unlink_qh		skelqh[SKEL_UNLINK]
#define SKEL_ISO		1
#define skel_iso_qh		skelqh[SKEL_ISO]
	/* int128, int64, ..., int1 = 2, 3, ..., 9 */
#define SKEL_INDEX(exponent)	(9 - exponent)
#define SKEL_ASYNC		9
#define skel_async_qh		skelqh[SKEL_ASYNC]
#define SKEL_TERM		10
#define skel_term_qh		skelqh[SKEL_TERM]

/* The following entries refer to sublists of skel_async_qh */
#define SKEL_LS_CONTROL		20
#define SKEL_FS_CONTROL		21
#define SKEL_FSBR		SKEL_FS_CONTROL
#define SKEL_BULK		22

/*
 *	The UHCI controller and root hub
 */

/*
 * States for the root hub:
 *
 * To prevent "bouncing" in the presence of electrical noise,
 * when there are no devices attached we delay for 1 second in the
 * RUNNING_NODEVS state before switching to the AUTO_STOPPED state.
 * 
 * (Note that the AUTO_STOPPED state won't be necessary once the hub
 * driver learns to autosuspend.)
 */
enum uhci_rh_state {
	/* In the following states the HC must be halted.
	 * These two must come first. */
	UHCI_RH_RESET,
	UHCI_RH_SUSPENDED,

	UHCI_RH_AUTO_STOPPED,
	UHCI_RH_RESUMING,

	/* In this state the HC changes from running to halted,
	 * so it can legally appear either way. */
	UHCI_RH_SUSPENDING,

	/* In the following states it's an error if the HC is halted.
	 * These two must come last. */
	UHCI_RH_RUNNING,		/* The normal state */
	UHCI_RH_RUNNING_NODEVS,		/* Running with no devices attached */
};

/*
 * The full UHCI controller information:
 */
struct uhci_hcd {

	/* debugfs */
	struct dentry *dentry;

	/* Grabbed from PCI */
	unsigned long io_addr;

	struct dma_pool *qh_pool;
	struct dma_pool *td_pool;

	struct uhci_td *term_td;	/* Terminating TD, see UHCI bug */
	struct uhci_qh *skelqh[UHCI_NUM_SKELQH];	/* Skeleton QHs */
	struct uhci_qh *next_qh;	/* Next QH to scan */

	spinlock_t lock;

	dma_addr_t frame_dma_handle;	/* Hardware frame list */
	__le32 *frame;
	void **frame_cpu;		/* CPU's frame list */

	enum uhci_rh_state rh_state;
	unsigned long auto_stop_time;		/* When to AUTO_STOP */

	unsigned int frame_number;		/* As of last check */
	unsigned int is_stopped;
#define UHCI_IS_STOPPED		9999		/* Larger than a frame # */
	unsigned int last_iso_frame;		/* Frame of last scan */
	unsigned int cur_iso_frame;		/* Frame for current scan */

	unsigned int scan_in_progress:1;	/* Schedule scan is running */
	unsigned int need_rescan:1;		/* Redo the schedule scan */
	unsigned int dead:1;			/* Controller has died */
	unsigned int working_RD:1;		/* Suspended root hub doesn't
						   need to be polled */
	unsigned int is_initialized:1;		/* Data structure is usable */
	unsigned int fsbr_is_on:1;		/* FSBR is turned on */
	unsigned int fsbr_is_wanted:1;		/* Does any URB want FSBR? */
	unsigned int fsbr_expiring:1;		/* FSBR is timing out */

	struct timer_list fsbr_timer;		/* For turning off FBSR */

	/* Support for port suspend/resume/reset */
	unsigned long port_c_suspend;		/* Bit-arrays of ports */
	unsigned long resuming_ports;
	unsigned long ports_timeout;		/* Time to stop signalling */

	struct list_head idle_qh_list;		/* Where the idle QHs live */

	int rh_numports;			/* Number of root-hub ports */

	wait_queue_head_t waitqh;		/* endpoint_disable waiters */
	int num_waiting;			/* Number of waiters */

	int total_load;				/* Sum of array values */
	short load[MAX_PHASE];			/* Periodic allocations */
};

/* Convert between a usb_hcd pointer and the corresponding uhci_hcd */
static inline struct uhci_hcd *hcd_to_uhci(struct usb_hcd *hcd)
{
	return (struct uhci_hcd *) (hcd->hcd_priv);
}
static inline struct usb_hcd *uhci_to_hcd(struct uhci_hcd *uhci)
{
	return container_of((void *) uhci, struct usb_hcd, hcd_priv);
}

#define uhci_dev(u)	(uhci_to_hcd(u)->self.controller)

/* Utility macro for comparing frame numbers */
#define uhci_frame_before_eq(f1, f2)	(0 <= (int) ((f2) - (f1)))


/*
 *	Private per-URB data
 */
struct urb_priv {
	struct list_head node;		/* Node in the QH's urbp list */

	struct urb *urb;

	struct uhci_qh *qh;		/* QH for this URB */
	struct list_head td_list;

	unsigned fsbr:1;		/* URB wants FSBR */
};


/*
 * Locking in uhci.c
 *
 * Almost everything relating to the hardware schedule and processing
 * of URBs is protected by uhci->lock.  urb->status is protected by
 * urb->lock; that's the one exception.
 *
 * To prevent deadlocks, never lock uhci->lock while holding urb->lock.
 * The safe order of locking is:
 *
 * #1 uhci->lock
 * #2 urb->lock
 */


/* Some special IDs */

#define PCI_VENDOR_ID_GENESYS		0x17a0
#define PCI_DEVICE_ID_GL880S_UHCI	0x8083

#endif