xref: /openbmc/linux/drivers/usb/host/uhci-hcd.h (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 #ifndef __LINUX_UHCI_HCD_H
2 #define __LINUX_UHCI_HCD_H
3 
4 #include <linux/list.h>
5 #include <linux/usb.h>
6 
7 #define usb_packetid(pipe)	(usb_pipein(pipe) ? USB_PID_IN : USB_PID_OUT)
8 #define PIPE_DEVEP_MASK		0x0007ff00
9 
10 /*
11  * Universal Host Controller Interface data structures and defines
12  */
13 
14 /* Command register */
15 #define USBCMD		0
16 #define   USBCMD_RS		0x0001	/* Run/Stop */
17 #define   USBCMD_HCRESET	0x0002	/* Host reset */
18 #define   USBCMD_GRESET		0x0004	/* Global reset */
19 #define   USBCMD_EGSM		0x0008	/* Global Suspend Mode */
20 #define   USBCMD_FGR		0x0010	/* Force Global Resume */
21 #define   USBCMD_SWDBG		0x0020	/* SW Debug mode */
22 #define   USBCMD_CF		0x0040	/* Config Flag (sw only) */
23 #define   USBCMD_MAXP		0x0080	/* Max Packet (0 = 32, 1 = 64) */
24 
25 /* Status register */
26 #define USBSTS		2
27 #define   USBSTS_USBINT		0x0001	/* Interrupt due to IOC */
28 #define   USBSTS_ERROR		0x0002	/* Interrupt due to error */
29 #define   USBSTS_RD		0x0004	/* Resume Detect */
30 #define   USBSTS_HSE		0x0008	/* Host System Error - basically PCI problems */
31 #define   USBSTS_HCPE		0x0010	/* Host Controller Process Error - the scripts were buggy */
32 #define   USBSTS_HCH		0x0020	/* HC Halted */
33 
34 /* Interrupt enable register */
35 #define USBINTR		4
36 #define   USBINTR_TIMEOUT	0x0001	/* Timeout/CRC error enable */
37 #define   USBINTR_RESUME	0x0002	/* Resume interrupt enable */
38 #define   USBINTR_IOC		0x0004	/* Interrupt On Complete enable */
39 #define   USBINTR_SP		0x0008	/* Short packet interrupt enable */
40 
41 #define USBFRNUM	6
42 #define USBFLBASEADD	8
43 #define USBSOF		12
44 
45 /* USB port status and control registers */
46 #define USBPORTSC1	16
47 #define USBPORTSC2	18
48 #define   USBPORTSC_CCS		0x0001	/* Current Connect Status ("device present") */
49 #define   USBPORTSC_CSC		0x0002	/* Connect Status Change */
50 #define   USBPORTSC_PE		0x0004	/* Port Enable */
51 #define   USBPORTSC_PEC		0x0008	/* Port Enable Change */
52 #define   USBPORTSC_DPLUS	0x0010	/* D+ high (line status) */
53 #define   USBPORTSC_DMINUS	0x0020	/* D- high (line status) */
54 #define   USBPORTSC_RD		0x0040	/* Resume Detect */
55 #define   USBPORTSC_RES1	0x0080	/* reserved, always 1 */
56 #define   USBPORTSC_LSDA	0x0100	/* Low Speed Device Attached */
57 #define   USBPORTSC_PR		0x0200	/* Port Reset */
58 /* OC and OCC from Intel 430TX and later (not UHCI 1.1d spec) */
59 #define   USBPORTSC_OC		0x0400	/* Over Current condition */
60 #define   USBPORTSC_OCC		0x0800	/* Over Current Change R/WC */
61 #define   USBPORTSC_SUSP	0x1000	/* Suspend */
62 #define   USBPORTSC_RES2	0x2000	/* reserved, write zeroes */
63 #define   USBPORTSC_RES3	0x4000	/* reserved, write zeroes */
64 #define   USBPORTSC_RES4	0x8000	/* reserved, write zeroes */
65 
66 /* Legacy support register */
67 #define USBLEGSUP		0xc0
68 #define   USBLEGSUP_DEFAULT	0x2000	/* only PIRQ enable set */
69 
70 #define UHCI_NULL_DATA_SIZE	0x7FF	/* for UHCI controller TD */
71 
72 #define UHCI_PTR_BITS		cpu_to_le32(0x000F)
73 #define UHCI_PTR_TERM		cpu_to_le32(0x0001)
74 #define UHCI_PTR_QH		cpu_to_le32(0x0002)
75 #define UHCI_PTR_DEPTH		cpu_to_le32(0x0004)
76 #define UHCI_PTR_BREADTH	cpu_to_le32(0x0000)
77 
78 #define UHCI_NUMFRAMES		1024	/* in the frame list [array] */
79 #define UHCI_MAX_SOF_NUMBER	2047	/* in an SOF packet */
80 #define CAN_SCHEDULE_FRAMES	1000	/* how far future frames can be scheduled */
81 
82 struct uhci_frame_list {
83 	__le32 frame[UHCI_NUMFRAMES];
84 
85 	void *frame_cpu[UHCI_NUMFRAMES];
86 
87 	dma_addr_t dma_handle;
88 };
89 
90 struct urb_priv;
91 
92 /*
93  * One role of a QH is to hold a queue of TDs for some endpoint.  Each QH is
94  * used with one URB, and qh->element (updated by the HC) is either:
95  *   - the next unprocessed TD for the URB, or
96  *   - UHCI_PTR_TERM (when there's no more traffic for this endpoint), or
97  *   - the QH for the next URB queued to the same endpoint.
98  *
99  * The other role of a QH is to serve as a "skeleton" framelist entry, so we
100  * can easily splice a QH for some endpoint into the schedule at the right
101  * place.  Then qh->element is UHCI_PTR_TERM.
102  *
103  * In the frame list, qh->link maintains a list of QHs seen by the HC:
104  *     skel1 --> ep1-qh --> ep2-qh --> ... --> skel2 --> ...
105  */
106 struct uhci_qh {
107 	/* Hardware fields */
108 	__le32 link;			/* Next queue */
109 	__le32 element;			/* Queue element pointer */
110 
111 	/* Software fields */
112 	dma_addr_t dma_handle;
113 
114 	struct usb_device *dev;
115 	struct urb_priv *urbp;
116 
117 	struct list_head list;		/* P: uhci->frame_list_lock */
118 	struct list_head remove_list;	/* P: uhci->remove_list_lock */
119 } __attribute__((aligned(16)));
120 
121 /*
122  * We need a special accessor for the element pointer because it is
123  * subject to asynchronous updates by the controller
124  */
125 static __le32 inline qh_element(struct uhci_qh *qh) {
126 	__le32 element = qh->element;
127 
128 	barrier();
129 	return element;
130 }
131 
132 /*
133  * for TD <status>:
134  */
135 #define TD_CTRL_SPD		(1 << 29)	/* Short Packet Detect */
136 #define TD_CTRL_C_ERR_MASK	(3 << 27)	/* Error Counter bits */
137 #define TD_CTRL_C_ERR_SHIFT	27
138 #define TD_CTRL_LS		(1 << 26)	/* Low Speed Device */
139 #define TD_CTRL_IOS		(1 << 25)	/* Isochronous Select */
140 #define TD_CTRL_IOC		(1 << 24)	/* Interrupt on Complete */
141 #define TD_CTRL_ACTIVE		(1 << 23)	/* TD Active */
142 #define TD_CTRL_STALLED		(1 << 22)	/* TD Stalled */
143 #define TD_CTRL_DBUFERR		(1 << 21)	/* Data Buffer Error */
144 #define TD_CTRL_BABBLE		(1 << 20)	/* Babble Detected */
145 #define TD_CTRL_NAK		(1 << 19)	/* NAK Received */
146 #define TD_CTRL_CRCTIMEO	(1 << 18)	/* CRC/Time Out Error */
147 #define TD_CTRL_BITSTUFF	(1 << 17)	/* Bit Stuff Error */
148 #define TD_CTRL_ACTLEN_MASK	0x7FF	/* actual length, encoded as n - 1 */
149 
150 #define TD_CTRL_ANY_ERROR	(TD_CTRL_STALLED | TD_CTRL_DBUFERR | \
151 				 TD_CTRL_BABBLE | TD_CTRL_CRCTIME | TD_CTRL_BITSTUFF)
152 
153 #define uhci_maxerr(err)		((err) << TD_CTRL_C_ERR_SHIFT)
154 #define uhci_status_bits(ctrl_sts)	((ctrl_sts) & 0xF60000)
155 #define uhci_actual_length(ctrl_sts)	(((ctrl_sts) + 1) & TD_CTRL_ACTLEN_MASK) /* 1-based */
156 
157 /*
158  * for TD <info>: (a.k.a. Token)
159  */
160 #define td_token(td)		le32_to_cpu((td)->token)
161 #define TD_TOKEN_DEVADDR_SHIFT	8
162 #define TD_TOKEN_TOGGLE_SHIFT	19
163 #define TD_TOKEN_TOGGLE		(1 << 19)
164 #define TD_TOKEN_EXPLEN_SHIFT	21
165 #define TD_TOKEN_EXPLEN_MASK	0x7FF		/* expected length, encoded as n - 1 */
166 #define TD_TOKEN_PID_MASK	0xFF
167 
168 #define uhci_explen(len)	((len) << TD_TOKEN_EXPLEN_SHIFT)
169 
170 #define uhci_expected_length(token) ((((token) >> 21) + 1) & TD_TOKEN_EXPLEN_MASK)
171 #define uhci_toggle(token)	(((token) >> TD_TOKEN_TOGGLE_SHIFT) & 1)
172 #define uhci_endpoint(token)	(((token) >> 15) & 0xf)
173 #define uhci_devaddr(token)	(((token) >> TD_TOKEN_DEVADDR_SHIFT) & 0x7f)
174 #define uhci_devep(token)	(((token) >> TD_TOKEN_DEVADDR_SHIFT) & 0x7ff)
175 #define uhci_packetid(token)	((token) & TD_TOKEN_PID_MASK)
176 #define uhci_packetout(token)	(uhci_packetid(token) != USB_PID_IN)
177 #define uhci_packetin(token)	(uhci_packetid(token) == USB_PID_IN)
178 
179 /*
180  * The documentation says "4 words for hardware, 4 words for software".
181  *
182  * That's silly, the hardware doesn't care. The hardware only cares that
183  * the hardware words are 16-byte aligned, and we can have any amount of
184  * sw space after the TD entry as far as I can tell.
185  *
186  * But let's just go with the documentation, at least for 32-bit machines.
187  * On 64-bit machines we probably want to take advantage of the fact that
188  * hw doesn't really care about the size of the sw-only area.
189  *
190  * Alas, not anymore, we have more than 4 words for software, woops.
191  * Everything still works tho, surprise! -jerdfelt
192  *
193  * td->link points to either another TD (not necessarily for the same urb or
194  * even the same endpoint), or nothing (PTR_TERM), or a QH (for queued urbs)
195  */
196 struct uhci_td {
197 	/* Hardware fields */
198 	__le32 link;
199 	__le32 status;
200 	__le32 token;
201 	__le32 buffer;
202 
203 	/* Software fields */
204 	dma_addr_t dma_handle;
205 
206 	struct usb_device *dev;
207 	struct urb *urb;
208 
209 	struct list_head list;		/* P: urb->lock */
210 	struct list_head remove_list;	/* P: uhci->td_remove_list_lock */
211 
212 	int frame;			/* for iso: what frame? */
213 	struct list_head fl_list;	/* P: uhci->frame_list_lock */
214 } __attribute__((aligned(16)));
215 
216 /*
217  * We need a special accessor for the control/status word because it is
218  * subject to asynchronous updates by the controller
219  */
220 static u32 inline td_status(struct uhci_td *td) {
221 	__le32 status = td->status;
222 
223 	barrier();
224 	return le32_to_cpu(status);
225 }
226 
227 
228 /*
229  * The UHCI driver places Interrupt, Control and Bulk into QH's both
230  * to group together TD's for one transfer, and also to faciliate queuing
231  * of URB's. To make it easy to insert entries into the schedule, we have
232  * a skeleton of QH's for each predefined Interrupt latency, low-speed
233  * control, full-speed control and terminating QH (see explanation for
234  * the terminating QH below).
235  *
236  * When we want to add a new QH, we add it to the end of the list for the
237  * skeleton QH.
238  *
239  * For instance, the queue can look like this:
240  *
241  * skel int128 QH
242  * dev 1 interrupt QH
243  * dev 5 interrupt QH
244  * skel int64 QH
245  * skel int32 QH
246  * ...
247  * skel int1 QH
248  * skel low-speed control QH
249  * dev 5 control QH
250  * skel full-speed control QH
251  * skel bulk QH
252  * dev 1 bulk QH
253  * dev 2 bulk QH
254  * skel terminating QH
255  *
256  * The terminating QH is used for 2 reasons:
257  * - To place a terminating TD which is used to workaround a PIIX bug
258  *   (see Intel errata for explanation)
259  * - To loop back to the full-speed control queue for full-speed bandwidth
260  *   reclamation
261  *
262  * Isochronous transfers are stored before the start of the skeleton
263  * schedule and don't use QH's. While the UHCI spec doesn't forbid the
264  * use of QH's for Isochronous, it doesn't use them either. Since we don't
265  * need to use them either, we follow the spec diagrams in hope that it'll
266  * be more compatible with future UHCI implementations.
267  */
268 
269 #define UHCI_NUM_SKELQH		12
270 #define skel_int128_qh		skelqh[0]
271 #define skel_int64_qh		skelqh[1]
272 #define skel_int32_qh		skelqh[2]
273 #define skel_int16_qh		skelqh[3]
274 #define skel_int8_qh		skelqh[4]
275 #define skel_int4_qh		skelqh[5]
276 #define skel_int2_qh		skelqh[6]
277 #define skel_int1_qh		skelqh[7]
278 #define skel_ls_control_qh	skelqh[8]
279 #define skel_fs_control_qh	skelqh[9]
280 #define skel_bulk_qh		skelqh[10]
281 #define skel_term_qh		skelqh[11]
282 
283 /*
284  * Search tree for determining where <interval> fits in the skelqh[]
285  * skeleton.
286  *
287  * An interrupt request should be placed into the slowest skelqh[]
288  * which meets the interval/period/frequency requirement.
289  * An interrupt request is allowed to be faster than <interval> but not slower.
290  *
291  * For a given <interval>, this function returns the appropriate/matching
292  * skelqh[] index value.
293  */
294 static inline int __interval_to_skel(int interval)
295 {
296 	if (interval < 16) {
297 		if (interval < 4) {
298 			if (interval < 2)
299 				return 7;	/* int1 for 0-1 ms */
300 			return 6;		/* int2 for 2-3 ms */
301 		}
302 		if (interval < 8)
303 			return 5;		/* int4 for 4-7 ms */
304 		return 4;			/* int8 for 8-15 ms */
305 	}
306 	if (interval < 64) {
307 		if (interval < 32)
308 			return 3;		/* int16 for 16-31 ms */
309 		return 2;			/* int32 for 32-63 ms */
310 	}
311 	if (interval < 128)
312 		return 1;			/* int64 for 64-127 ms */
313 	return 0;				/* int128 for 128-255 ms (Max.) */
314 }
315 
316 /*
317  * Device states for the host controller.
318  *
319  * To prevent "bouncing" in the presence of electrical noise,
320  * we insist on a 1-second "grace" period, before switching to
321  * the RUNNING or SUSPENDED states, during which the state is
322  * not allowed to change.
323  *
324  * The resume process is divided into substates in order to avoid
325  * potentially length delays during the timer handler.
326  *
327  * States in which the host controller is halted must have values <= 0.
328  */
329 enum uhci_state {
330 	UHCI_RESET,
331 	UHCI_RUNNING_GRACE,		/* Before RUNNING */
332 	UHCI_RUNNING,			/* The normal state */
333 	UHCI_SUSPENDING_GRACE,		/* Before SUSPENDED */
334 	UHCI_SUSPENDED = -10,		/* When no devices are attached */
335 	UHCI_RESUMING_1,
336 	UHCI_RESUMING_2
337 };
338 
339 /*
340  * This describes the full uhci information.
341  *
342  * Note how the "proper" USB information is just
343  * a subset of what the full implementation needs.
344  */
345 struct uhci_hcd {
346 
347 	/* debugfs */
348 	struct dentry *dentry;
349 
350 	/* Grabbed from PCI */
351 	unsigned long io_addr;
352 
353 	struct dma_pool *qh_pool;
354 	struct dma_pool *td_pool;
355 
356 	struct usb_bus *bus;
357 
358 	struct uhci_td *term_td;	/* Terminating TD, see UHCI bug */
359 	struct uhci_qh *skelqh[UHCI_NUM_SKELQH];	/* Skeleton QH's */
360 
361 	spinlock_t lock;
362 	struct uhci_frame_list *fl;		/* P: uhci->lock */
363 	int fsbr;				/* Full-speed bandwidth reclamation */
364 	unsigned long fsbrtimeout;		/* FSBR delay */
365 
366 	enum uhci_state state;			/* FIXME: needs a spinlock */
367 	unsigned long state_end;		/* Time of next transition */
368 	unsigned int frame_number;		/* As of last check */
369 	unsigned int is_stopped;
370 #define UHCI_IS_STOPPED		9999		/* Larger than a frame # */
371 
372 	unsigned int scan_in_progress:1;	/* Schedule scan is running */
373 	unsigned int need_rescan:1;		/* Redo the schedule scan */
374 	unsigned int resume_detect:1;		/* Need a Global Resume */
375 
376 	/* Support for port suspend/resume/reset */
377 	unsigned long port_c_suspend;		/* Bit-arrays of ports */
378 	unsigned long suspended_ports;
379 	unsigned long resuming_ports;
380 	unsigned long ports_timeout;		/* Time to stop signalling */
381 
382 	/* Main list of URB's currently controlled by this HC */
383 	struct list_head urb_list;		/* P: uhci->lock */
384 
385 	/* List of QH's that are done, but waiting to be unlinked (race) */
386 	struct list_head qh_remove_list;	/* P: uhci->lock */
387 	unsigned int qh_remove_age;		/* Age in frames */
388 
389 	/* List of TD's that are done, but waiting to be freed (race) */
390 	struct list_head td_remove_list;	/* P: uhci->lock */
391 	unsigned int td_remove_age;		/* Age in frames */
392 
393 	/* List of asynchronously unlinked URB's */
394 	struct list_head urb_remove_list;	/* P: uhci->lock */
395 	unsigned int urb_remove_age;		/* Age in frames */
396 
397 	/* List of URB's awaiting completion callback */
398 	struct list_head complete_list;		/* P: uhci->lock */
399 
400 	int rh_numports;
401 
402 	struct timer_list stall_timer;
403 
404 	wait_queue_head_t waitqh;		/* endpoint_disable waiters */
405 };
406 
407 /* Convert between a usb_hcd pointer and the corresponding uhci_hcd */
408 static inline struct uhci_hcd *hcd_to_uhci(struct usb_hcd *hcd)
409 {
410 	return (struct uhci_hcd *) (hcd->hcd_priv);
411 }
412 static inline struct usb_hcd *uhci_to_hcd(struct uhci_hcd *uhci)
413 {
414 	return container_of((void *) uhci, struct usb_hcd, hcd_priv);
415 }
416 
417 #define uhci_dev(u)	(uhci_to_hcd(u)->self.controller)
418 
419 struct urb_priv {
420 	struct list_head urb_list;
421 
422 	struct urb *urb;
423 
424 	struct uhci_qh *qh;		/* QH for this URB */
425 	struct list_head td_list;	/* P: urb->lock */
426 
427 	unsigned fsbr : 1;		/* URB turned on FSBR */
428 	unsigned fsbr_timeout : 1;	/* URB timed out on FSBR */
429 	unsigned queued : 1;		/* QH was queued (not linked in) */
430 	unsigned short_control_packet : 1;	/* If we get a short packet during */
431 						/*  a control transfer, retrigger */
432 						/*  the status phase */
433 
434 	unsigned long inserttime;	/* In jiffies */
435 	unsigned long fsbrtime;		/* In jiffies */
436 
437 	struct list_head queue_list;	/* P: uhci->frame_list_lock */
438 };
439 
440 /*
441  * Locking in uhci.c
442  *
443  * Almost everything relating to the hardware schedule and processing
444  * of URBs is protected by uhci->lock.  urb->status is protected by
445  * urb->lock; that's the one exception.
446  *
447  * To prevent deadlocks, never lock uhci->lock while holding urb->lock.
448  * The safe order of locking is:
449  *
450  * #1 uhci->lock
451  * #2 urb->lock
452  */
453 
454 #endif
455