1 /*
2  * Standalone EHCI USB debug driver
3  *
4  * Hardware interface code based on the respective early console driver in
5  * Linux; see the Linux source for authorship and copyrights.
6  */
7 
8 #include <xen/console.h>
9 #include <xen/delay.h>
10 #include <xen/errno.h>
11 #include <xen/param.h>
12 #include <xen/pci.h>
13 #include <xen/serial.h>
14 #include <asm/byteorder.h>
15 #include <asm/io.h>
16 #include <asm/fixmap.h>
17 #include <public/physdev.h>
18 
19 /* #define DBGP_DEBUG */
20 
21 /* EHCI register interface, corresponds to EHCI Revision 0.95 specification */
22 
23 /* Section 2.2 Host Controller Capability Registers */
24 struct ehci_caps {
25     /*
26      * These fields are specified as 8 and 16 bit registers,
27      * but some hosts can't perform 8 or 16 bit PCI accesses.
28      * some hosts treat caplength and hciversion as parts of a 32-bit
29      * register, others treat them as two separate registers, this
30      * affects the memory map for big endian controllers.
31      */
32     u32 hc_capbase;
33 #define HC_LENGTH(p)      (0x00ff & (p)) /* bits 7:0 / offset 0x00 */
34 #define HC_VERSION(p)     (0xffff & ((p) >> 16)) /* bits 31:16 / offset 0x02 */
35 
36     u32 hcs_params;       /* HCSPARAMS - offset 0x04 */
37 #define HCS_DEBUG_PORT(p) (((p) >> 20) & 0xf) /* bits 23:20, debug port? */
38 #define HCS_INDICATOR(p)  ((p) & (1 << 16))   /* true: has port indicators */
39 #define HCS_N_CC(p)       (((p) >> 12) & 0xf) /* bits 15:12, #companion HCs */
40 #define HCS_N_PCC(p)      (((p) >> 8) & 0xf)  /* bits 11:8, ports per CC */
41 #define HCS_PORTROUTED(p) ((p) & (1 << 7))    /* true: port routing */
42 #define HCS_PPC(p)        ((p) & (1 << 4))    /* true: port power control */
43 #define HCS_N_PORTS(p)    (((p) >> 0) & 0xf)  /* bits 3:0, ports on HC */
44 
45     u32 hcc_params;       /* HCCPARAMS - offset 0x08 */
46 /* EHCI 1.1 addendum */
47 #define HCC_32FRAME_PERIODIC_LIST(p) ((p) & (1 << 19))
48 #define HCC_PER_PORT_CHANGE_EVENT(p) ((p) & (1 << 18))
49 #define HCC_LPM(p)        ((p) & (1 << 17))
50 #define HCC_HW_PREFETCH(p) ((p) & (1 << 16))
51 #define HCC_EXT_CAPS(p)   (((p) >> 8) & 0xff) /* for pci extended caps */
52 #define HCC_ISOC_CACHE(p) ((p) & (1 << 7))    /* true: can cache isoc frame */
53 #define HCC_ISOC_THRES(p) (((p) >> 4) & 0x7)  /* bits 6:4, uframes cached */
54 #define HCC_CANPARK(p)    ((p) & (1 << 2))    /* true: can park on async qh */
55 #define HCC_PGM_FRAMELISTLEN(p) ((p) & (1 << 1)) /* true: periodic_size changes */
56 #define HCC_64BIT_ADDR(p) ((p) & 1)           /* true: can use 64-bit addr */
57 
58     u8  portroute[8];     /* nibbles for routing - offset 0x0C */
59 };
60 
61 /* Section 2.3 Host Controller Operational Registers */
62 struct ehci_regs {
63     /* USBCMD: offset 0x00 */
64     u32 command;
65 
66 /* EHCI 1.1 addendum */
67 #define CMD_HIRD        (0xf << 24) /* host initiated resume duration */
68 #define CMD_PPCEE       (1 << 15)   /* per port change event enable */
69 #define CMD_FSP         (1 << 14)   /* fully synchronized prefetch */
70 #define CMD_ASPE        (1 << 13)   /* async schedule prefetch enable */
71 #define CMD_PSPE        (1 << 12)   /* periodic schedule prefetch enable */
72 /* 23:16 is r/w intr rate, in microframes; default "8" == 1/msec */
73 #define CMD_PARK        (1 << 11)   /* enable "park" on async qh */
74 #define CMD_PARK_CNT(c) (((c) >> 8) & 3) /* how many transfers to park for */
75 #define CMD_LRESET      (1 << 7)    /* partial reset (no ports, etc) */
76 #define CMD_IAAD        (1 << 6)    /* "doorbell" interrupt async advance */
77 #define CMD_ASE         (1 << 5)    /* async schedule enable */
78 #define CMD_PSE         (1 << 4)    /* periodic schedule enable */
79 /* 3:2 is periodic frame list size */
80 #define CMD_RESET       (1 << 1)    /* reset HC not bus */
81 #define CMD_RUN         (1 << 0)    /* start/stop HC */
82 
83     /* USBSTS: offset 0x04 */
84     u32 status;
85 #define STS_PPCE_MASK   (0xff << 16) /* Per-Port change event 1-16 */
86 #define STS_ASS         (1 << 15)   /* Async Schedule Status */
87 #define STS_PSS         (1 << 14)   /* Periodic Schedule Status */
88 #define STS_RECL        (1 << 13)   /* Reclamation */
89 #define STS_HALT        (1 << 12)   /* Not running (any reason) */
90 /* some bits reserved */
91     /* these STS_* flags are also intr_enable bits (USBINTR) */
92 #define STS_IAA         (1 << 5)    /* Interrupted on async advance */
93 #define STS_FATAL       (1 << 4)    /* such as some PCI access errors */
94 #define STS_FLR         (1 << 3)    /* frame list rolled over */
95 #define STS_PCD         (1 << 2)    /* port change detect */
96 #define STS_ERR         (1 << 1)    /* "error" completion (overflow, ...) */
97 #define STS_INT         (1 << 0)    /* "normal" completion (short, ...) */
98 
99     /* USBINTR: offset 0x08 */
100     u32 intr_enable;
101 
102     /* FRINDEX: offset 0x0C */
103     u32 frame_index;    /* current microframe number */
104     /* CTRLDSSEGMENT: offset 0x10 */
105     u32 segment;    /* address bits 63:32 if needed */
106     /* PERIODICLISTBASE: offset 0x14 */
107     u32 frame_list;    /* points to periodic list */
108     /* ASYNCLISTADDR: offset 0x18 */
109     u32 async_next;    /* address of next async queue head */
110 
111     u32 reserved[9];
112 
113     /* CONFIGFLAG: offset 0x40 */
114     u32 configured_flag;
115 #define FLAG_CF         (1 << 0)    /* true: we'll support "high speed" */
116 
117     /* PORTSC: offset 0x44 */
118     u32 port_status[0];    /* up to N_PORTS */
119 /* EHCI 1.1 addendum */
120 #define PORTSC_SUSPEND_STS_ACK   0
121 #define PORTSC_SUSPEND_STS_NYET  1
122 #define PORTSC_SUSPEND_STS_STALL 2
123 #define PORTSC_SUSPEND_STS_ERR   3
124 
125 #define PORT_DEV_ADDR   (0x7f << 25) /* device address */
126 #define PORT_SSTS       (0x3 << 23)  /* suspend status */
127 /* 31:23 reserved */
128 #define PORT_WKOC_E     (1 << 22)    /* wake on overcurrent (enable) */
129 #define PORT_WKDISC_E   (1 << 21)    /* wake on disconnect (enable) */
130 #define PORT_WKCONN_E   (1 << 20)    /* wake on connect (enable) */
131 /* 19:16 for port testing */
132 #define PORT_TEST(x)    (((x) & 0xf) << 16) /* Port Test Control */
133 #define PORT_TEST_PKT   PORT_TEST(0x4) /* Port Test Control - packet test */
134 #define PORT_TEST_FORCE PORT_TEST(0x5) /* Port Test Control - force enable */
135 #define PORT_LED_OFF    (0 << 14)
136 #define PORT_LED_AMBER  (1 << 14)
137 #define PORT_LED_GREEN  (2 << 14)
138 #define PORT_LED_MASK   (3 << 14)
139 #define PORT_OWNER      (1 << 13)    /* true: companion hc owns this port */
140 #define PORT_POWER      (1 << 12)    /* true: has power (see PPC) */
141 #define PORT_USB11(x)   (((x) & (3 << 10)) == (1 << 10)) /* USB 1.1 device */
142 /* 11:10 for detecting lowspeed devices (reset vs release ownership) */
143 /* 9 reserved */
144 #define PORT_LPM        (1 << 9)     /* LPM transaction */
145 #define PORT_RESET      (1 << 8)     /* reset port */
146 #define PORT_SUSPEND    (1 << 7)     /* suspend port */
147 #define PORT_RESUME     (1 << 6)     /* resume it */
148 #define PORT_OCC        (1 << 5)     /* over current change */
149 #define PORT_OC         (1 << 4)     /* over current active */
150 #define PORT_PEC        (1 << 3)     /* port enable change */
151 #define PORT_PE         (1 << 2)     /* port enable */
152 #define PORT_CSC        (1 << 1)     /* connect status change */
153 #define PORT_CONNECT    (1 << 0)     /* device connected */
154 #define PORT_RWC_BITS   (PORT_CSC | PORT_PEC | PORT_OCC)
155 };
156 
157 /*
158  * Appendix C, Debug port ... intended for use with special "debug devices"
159  * that can help if there's no serial console.  (nonstandard enumeration.)
160  */
161 struct ehci_dbg_port {
162     u32 control;
163 #define DBGP_OWNER      (1 << 30)
164 #define DBGP_ENABLED    (1 << 28)
165 #define DBGP_DONE       (1 << 16)
166 #define DBGP_INUSE      (1 << 10)
167 #define DBGP_ERRCODE(x) (((x) >> 7) & 0x07)
168 # define DBGP_ERR_BAD    1
169 # define DBGP_ERR_SIGNAL 2
170 #define DBGP_ERROR      (1 << 6)
171 #define DBGP_GO         (1 << 5)
172 #define DBGP_OUT        (1 << 4)
173 #define DBGP_LEN        (0xf << 0)
174 #define DBGP_CLAIM      (DBGP_OWNER | DBGP_ENABLED | DBGP_INUSE)
175     u32 pids;
176 #define DBGP_PID_GET(x)         (((x) >> 16) & 0xff)
177 #define DBGP_PID_SET(data, tok) (((data) << 8) | (tok))
178     u32 data03;
179     u32 data47;
180     u32 address;
181 #define DBGP_EPADDR(dev, ep) (((dev) << 8) | (ep))
182 };
183 
184 /* CONTROL REQUEST SUPPORT */
185 
186 /*
187  * USB directions
188  *
189  * This bit flag is used in endpoint descriptors' bEndpointAddress field.
190  * It's also one of three fields in control requests bRequestType.
191  */
192 #define USB_DIR_OUT 0           /* to device */
193 #define USB_DIR_IN  0x80        /* to host */
194 
195 /*
196  * USB types, the second of three bRequestType fields
197  */
198 #define USB_TYPE_MASK     (0x03 << 5)
199 #define USB_TYPE_STANDARD (0x00 << 5)
200 #define USB_TYPE_CLASS    (0x01 << 5)
201 #define USB_TYPE_VENDOR   (0x02 << 5)
202 #define USB_TYPE_RESERVED (0x03 << 5)
203 
204 /*
205  * USB recipients, the third of three bRequestType fields
206  */
207 #define USB_RECIP_MASK      0x1f
208 #define USB_RECIP_DEVICE    0x00
209 #define USB_RECIP_INTERFACE 0x01
210 #define USB_RECIP_ENDPOINT  0x02
211 #define USB_RECIP_OTHER     0x03
212 /* From Wireless USB 1.0 */
213 #define USB_RECIP_PORT      0x04
214 #define USB_RECIP_RPIPE     0x05
215 
216 /*
217  * Standard requests, for the bRequest field of a SETUP packet.
218  *
219  * These are qualified by the bRequestType field, so that for example
220  * TYPE_CLASS or TYPE_VENDOR specific feature flags could be retrieved
221  * by a GET_STATUS request.
222  */
223 #define USB_REQ_GET_STATUS        0x00
224 #define USB_REQ_CLEAR_FEATURE     0x01
225 #define USB_REQ_SET_FEATURE       0x03
226 #define USB_REQ_SET_ADDRESS       0x05
227 #define USB_REQ_GET_DESCRIPTOR    0x06
228 #define USB_REQ_SET_DESCRIPTOR    0x07
229 #define USB_REQ_GET_CONFIGURATION 0x08
230 #define USB_REQ_SET_CONFIGURATION 0x09
231 #define USB_REQ_GET_INTERFACE     0x0A
232 #define USB_REQ_SET_INTERFACE     0x0B
233 #define USB_REQ_SYNCH_FRAME       0x0C
234 
235 #define USB_DEVICE_DEBUG_MODE        6    /* (special devices only) */
236 
237 /**
238  * struct usb_ctrlrequest - SETUP data for a USB device control request
239  * @bRequestType: matches the USB bmRequestType field
240  * @bRequest: matches the USB bRequest field
241  * @wValue: matches the USB wValue field (le16 byte order)
242  * @wIndex: matches the USB wIndex field (le16 byte order)
243  * @wLength: matches the USB wLength field (le16 byte order)
244  *
245  * This structure is used to send control requests to a USB device.  It matches
246  * the different fields of the USB 2.0 Spec section 9.3, table 9-2.  See the
247  * USB spec for a fuller description of the different fields, and what they are
248  * used for.
249  *
250  * Note that the driver for any interface can issue control requests.
251  * For most devices, interfaces don't coordinate with each other, so
252  * such requests may be made at any time.
253  */
254 struct __packed usb_ctrlrequest {
255     u8 bRequestType;
256     u8 bRequest;
257     __le16 wValue;
258     __le16 wIndex;
259     __le16 wLength;
260 };
261 
262 /* USB_DT_DEBUG: for special highspeed devices, replacing serial console */
263 
264 #define USB_DT_DEBUG    0x0a
265 
266 struct __packed usb_debug_descriptor {
267     u8 bLength;
268     u8 bDescriptorType;
269     /* bulk endpoints with 8 byte maxpacket */
270     u8 bDebugInEndpoint;
271     u8 bDebugOutEndpoint;
272 };
273 
274 #define USB_DEBUG_DEVNUM 127
275 
276 /*
277  * USB Packet IDs (PIDs)
278  */
279 
280 /* token */
281 #define USB_PID_OUT           0xe1
282 #define USB_PID_IN            0x69
283 #define USB_PID_SOF           0xa5
284 #define USB_PID_SETUP         0x2d
285 /* handshake */
286 #define USB_PID_ACK           0xd2
287 #define USB_PID_NAK           0x5a
288 #define USB_PID_STALL         0x1e
289 #define USB_PID_NYET          0x96
290 /* data */
291 #define USB_PID_DATA0         0xc3
292 #define USB_PID_DATA1         0x4b
293 #define USB_PID_DATA2         0x87
294 #define USB_PID_MDATA         0x0f
295 /* Special */
296 #define USB_PID_PREAMBLE      0x3c
297 #define USB_PID_ERR           0x3c
298 #define USB_PID_SPLIT         0x78
299 #define USB_PID_PING          0xb4
300 #define USB_PID_UNDEF_0       0xf0
301 
302 #define PCI_CLASS_SERIAL_USB_EHCI 0x0c0320
303 #define PCI_CAP_ID_EHCI_DEBUG     0x0a
304 
305 #define HUB_ROOT_RESET_TIME   50    /* times are in msec */
306 #define HUB_SHORT_RESET_TIME  10
307 #define HUB_LONG_RESET_TIME   200
308 #define HUB_RESET_TIMEOUT     500
309 
310 #define DBGP_MAX_PACKET       8
311 #define DBGP_LOOPS            1000
312 #define DBGP_TIMEOUT          (250 * 1000) /* us */
313 #define DBGP_CHECK_INTERVAL   100 /* us */
314 /* This one can be set arbitrarily - only affects input responsiveness: */
315 #define DBGP_IDLE_INTERVAL    100 /* ms */
316 
317 struct ehci_dbgp {
318     struct ehci_dbg_port __iomem *ehci_debug;
319     enum dbgp_state {
320         dbgp_idle,
321         dbgp_out,
322         dbgp_in,
323         dbgp_ctrl,
324         dbgp_unsafe /* cannot use debug device during EHCI reset */
325     } state;
326     unsigned int phys_port;
327     struct {
328         unsigned int endpoint;
329         unsigned int chunk;
330         char buf[DBGP_MAX_PACKET];
331     } out, in;
332     unsigned long timeout;
333     struct timer timer;
334     spinlock_t *lock;
335     bool_t reset_run;
336     u8 bus, slot, func, bar;
337     u16 pci_cr;
338     u32 bar_val;
339     unsigned int cap;
340     struct ehci_regs __iomem *ehci_regs;
341     struct ehci_caps __iomem *ehci_caps;
342 };
343 
344 static int ehci_dbgp_external_startup(struct ehci_dbgp *);
345 
ehci_dbgp_status(struct ehci_dbgp * dbgp,const char * str)346 static void ehci_dbgp_status(struct ehci_dbgp *dbgp, const char *str)
347 {
348 #ifdef DBGP_DEBUG
349 #define dbgp_printk printk
350     if ( !dbgp->ehci_debug )
351         return;
352     dbgp_printk("dbgp: %s\n", str);
353     dbgp_printk("  debug control: %08x\n", readl(&dbgp->ehci_debug->control));
354     dbgp_printk("  EHCI cmd     : %08x\n", readl(&dbgp->ehci_regs->command));
355     dbgp_printk("  EHCI conf flg: %08x\n",
356                 readl(&dbgp->ehci_regs->configured_flag));
357     dbgp_printk("  EHCI status  : %08x\n", readl(&dbgp->ehci_regs->status));
358     dbgp_printk("  EHCI portsc  : %08x\n",
359                 readl(&dbgp->ehci_regs->port_status[dbgp->phys_port - 1]));
360 #endif
361 }
362 
363 #ifndef DBGP_DEBUG
364 static inline __attribute__ ((format (printf, 1, 2))) void
dbgp_printk(const char * fmt,...)365 dbgp_printk(const char *fmt, ...) { }
366 #endif
367 
dbgp_len_update(u32 x,u32 len)368 static inline u32 dbgp_len_update(u32 x, u32 len)
369 {
370     return (x & ~DBGP_LEN) | (len & DBGP_LEN) | DBGP_OUT;
371 }
372 
dbgp_pid_write_update(u32 x,u32 tok)373 static inline u32 dbgp_pid_write_update(u32 x, u32 tok)
374 {
375     static u8 data0 = USB_PID_DATA1;
376 
377     data0 ^= USB_PID_DATA0 ^ USB_PID_DATA1;
378     return (x & 0xffff0000) | (data0 << 8) | (tok & 0xff);
379 }
380 
dbgp_pid_read_update(u32 x,u32 tok)381 static inline u32 dbgp_pid_read_update(u32 x, u32 tok)
382 {
383     return (x & 0xffffff00) | (tok & 0xff);
384 }
385 
dbgp_set_data(struct ehci_dbg_port __iomem * ehci_debug,const void * buf,unsigned int size)386 static inline void dbgp_set_data(struct ehci_dbg_port __iomem *ehci_debug,
387                                  const void *buf, unsigned int size)
388 {
389     const unsigned char *bytes = buf;
390     u32 lo = 0, hi = 0;
391     unsigned int i;
392 
393     for ( i = 0; i < 4 && i < size; i++ )
394         lo |= bytes[i] << (8 * i);
395     for ( ; i < 8 && i < size; i++ )
396         hi |= bytes[i] << (8 * (i - 4));
397     writel(lo, &ehci_debug->data03);
398     writel(hi, &ehci_debug->data47);
399 }
400 
dbgp_get_data(struct ehci_dbg_port __iomem * ehci_debug,void * buf,int size)401 static inline void dbgp_get_data(struct ehci_dbg_port __iomem *ehci_debug,
402                                  void *buf, int size)
403 {
404     unsigned char *bytes = buf;
405     u32 lo = readl(&ehci_debug->data03);
406     u32 hi = readl(&ehci_debug->data47);
407     unsigned int i;
408 
409     for ( i = 0; i < 4 && i < size; i++ )
410         bytes[i] = (lo >> (8 * i)) & 0xff;
411     for ( ; i < 8 && i < size; i++ )
412         bytes[i] = (hi >> (8 * (i - 4))) & 0xff;
413 }
414 
dbgp_issue_command(struct ehci_dbgp * dbgp,u32 ctrl,enum dbgp_state state)415 static void dbgp_issue_command(struct ehci_dbgp *dbgp, u32 ctrl,
416                                enum dbgp_state state)
417 {
418     u32 cmd = readl(&dbgp->ehci_regs->command);
419 
420     if ( unlikely(!(cmd & CMD_RUN)) )
421     {
422         /*
423          * If the EHCI controller is not in the run state do extended
424          * checks to see if ACPI or some other initialization also
425          * reset the EHCI debug port.
426          */
427         u32 ctrl = readl(&dbgp->ehci_debug->control);
428 
429         if ( ctrl & DBGP_ENABLED )
430         {
431             cmd |= CMD_RUN;
432             writel(cmd, &dbgp->ehci_regs->command);
433             dbgp->reset_run = 1;
434         }
435         else if ( dbgp->state != dbgp_unsafe )
436         {
437             dbgp->state = dbgp_unsafe;
438             ehci_dbgp_external_startup(dbgp);
439         }
440     }
441 
442     writel(ctrl | DBGP_GO, &dbgp->ehci_debug->control);
443     dbgp->timeout = DBGP_TIMEOUT;
444     if ( dbgp->state != dbgp_unsafe )
445         dbgp->state = state;
446 }
447 
dbgp_check_for_completion(struct ehci_dbgp * dbgp,unsigned int interval,u8 * ppid)448 static int dbgp_check_for_completion(struct ehci_dbgp *dbgp,
449                                      unsigned int interval, u8 *ppid)
450 {
451     u32 ctrl;
452     int ret;
453 
454     if ( dbgp->state == dbgp_idle )
455         return 0;
456 
457     ctrl = readl(&dbgp->ehci_debug->control) & ~DBGP_GO;
458     if ( !(ctrl & DBGP_DONE) )
459     {
460         if ( dbgp->timeout > interval )
461             dbgp->timeout -= interval;
462         else if ( interval )
463         {
464             /* See the timeout related comment in dbgp_wait_until_done(). */
465             dbgp->state = dbgp_unsafe;
466             dbgp->timeout = 0;
467         }
468         return -DBGP_TIMEOUT;
469     }
470 
471     if ( ctrl & DBGP_ERROR )
472     {
473         ret = -DBGP_ERRCODE(ctrl);
474         if ( ret == -DBGP_ERR_BAD && dbgp->timeout > interval )
475             ctrl |= DBGP_GO;
476     }
477     else
478     {
479         u8 pid = DBGP_PID_GET(readl(&dbgp->ehci_debug->pids));
480 
481         ret = ctrl & DBGP_LEN;
482         if ( ppid )
483             *ppid = pid;
484         else if ( dbgp->state == dbgp_in )
485         {
486             dbgp_get_data(dbgp->ehci_debug, dbgp->in.buf, ret);
487             dbgp->in.chunk = ret;
488         }
489         else if ( pid == USB_PID_NAK && dbgp->timeout > interval )
490             ctrl |= DBGP_GO;
491     }
492 
493     writel(ctrl, &dbgp->ehci_debug->control);
494     if ( ctrl & DBGP_GO )
495     {
496         dbgp->timeout -= interval;
497         return -DBGP_TIMEOUT;
498     }
499 
500     if ( unlikely(dbgp->reset_run) )
501     {
502         writel(readl(&dbgp->ehci_regs->command) & ~CMD_RUN,
503                &dbgp->ehci_regs->command);
504         dbgp->reset_run = 0;
505     }
506 
507     if ( dbgp->state != dbgp_unsafe )
508         dbgp->state = dbgp_idle;
509 
510     return ret;
511 }
512 
dbgp_wait_until_complete(struct ehci_dbgp * dbgp,u8 * ppid)513 static int dbgp_wait_until_complete(struct ehci_dbgp *dbgp, u8 *ppid)
514 {
515     unsigned int loop = DBGP_TIMEOUT;
516     int ret;
517 
518     do {
519         ret = dbgp_check_for_completion(dbgp, 0, ppid);
520         if ( ret != -DBGP_TIMEOUT )
521             break;
522         udelay(1);
523     } while ( --loop );
524 
525     if ( !ppid && !loop )
526         dbgp->state = dbgp_unsafe;
527 
528     return ret;
529 }
530 
dbgp_mdelay(unsigned int ms)531 static inline void dbgp_mdelay(unsigned int ms)
532 {
533     while ( ms-- )
534     {
535         unsigned int i;
536 
537         for ( i = 0; i < 1000; i++ )
538             outb(0x1, 0x80);
539     }
540 }
541 
dbgp_breathe(void)542 static void dbgp_breathe(void)
543 {
544     /* Sleep to give the debug port a chance to breathe. */
545     dbgp_mdelay(1);
546 }
547 
dbgp_wait_until_done(struct ehci_dbgp * dbgp,u32 ctrl,unsigned int loop)548 static int dbgp_wait_until_done(struct ehci_dbgp *dbgp, u32 ctrl,
549                                 unsigned int loop)
550 {
551     int ret;
552 
553     dbgp->timeout = 0;
554 
555     for ( ; ; writel(ctrl | DBGP_GO, &dbgp->ehci_debug->control) )
556     {
557         u8 pid;
558 
559         ret = dbgp_wait_until_complete(dbgp, &pid);
560         if ( ret < 0 )
561         {
562             /*
563              * A -DBGP_TIMEOUT failure here means the device has failed,
564              * perhaps because it was unplugged, in which case we do not
565              * want to hang the system so the dbgp will be marked as unsafe
566              * to use. EHCI reset is the only way to recover if you unplug
567              * the dbgp device.
568              */
569             if ( ret == -DBGP_TIMEOUT )
570                 dbgp->state = dbgp_unsafe;
571             if ( ret != -DBGP_ERR_BAD || !--loop )
572                 break;
573         }
574         else
575         {
576             /*
577              * If the port is getting full or it has dropped data
578              * start pacing ourselves, not necessary but it's friendly.
579              */
580             if ( pid == USB_PID_NAK || pid == USB_PID_NYET )
581                 dbgp_breathe();
582 
583             /* If we got a NACK, reissue the transmission. */
584             if ( pid != USB_PID_NAK || !--loop )
585                 break;
586         }
587     }
588 
589     return ret;
590 }
591 
dbgp_bulk_write(struct ehci_dbgp * dbgp,unsigned int devnum,unsigned int endpoint,const void * bytes,unsigned int size,u32 * pctrl)592 static int dbgp_bulk_write(struct ehci_dbgp *dbgp,
593                            unsigned int devnum, unsigned int endpoint,
594                            const void *bytes, unsigned int size, u32 *pctrl)
595 {
596     u32 addr, pids, ctrl;
597 
598     if ( size > DBGP_MAX_PACKET )
599         return -EINVAL;
600 
601     addr = DBGP_EPADDR(devnum, endpoint);
602     pids = dbgp_pid_write_update(readl(&dbgp->ehci_debug->pids), USB_PID_OUT);
603     ctrl = dbgp_len_update(readl(&dbgp->ehci_debug->control), size);
604     if ( pctrl )
605         *pctrl = ctrl;
606 
607     dbgp_set_data(dbgp->ehci_debug, bytes, size);
608     writel(addr, &dbgp->ehci_debug->address);
609     writel(pids, &dbgp->ehci_debug->pids);
610     dbgp_issue_command(dbgp, ctrl, dbgp_out);
611 
612     return 0;
613 }
614 
dbgp_bulk_read(struct ehci_dbgp * dbgp,unsigned int devnum,unsigned int endpoint,unsigned int size,u32 * pctrl)615 static int dbgp_bulk_read(struct ehci_dbgp *dbgp,
616                           unsigned int devnum, unsigned int endpoint,
617                           unsigned int size, u32 *pctrl)
618 {
619     u32 addr, pids, ctrl;
620 
621     if ( size > DBGP_MAX_PACKET )
622         return -EINVAL;
623 
624     addr = DBGP_EPADDR(devnum, endpoint);
625     pids = dbgp_pid_read_update(readl(&dbgp->ehci_debug->pids), USB_PID_IN);
626     ctrl = readl(&dbgp->ehci_debug->control) & ~DBGP_OUT;
627 
628     writel(addr, &dbgp->ehci_debug->address);
629     writel(pids, &dbgp->ehci_debug->pids);
630     if ( likely(!pctrl) )
631         dbgp_issue_command(dbgp, ctrl, dbgp_in);
632     else
633         dbgp_issue_command(dbgp, *pctrl = ctrl, dbgp_ctrl);
634 
635     return 0;
636 }
637 
dbgp_control_msg(struct ehci_dbgp * dbgp,unsigned int devnum,int requesttype,int request,int value,int index,void * data,unsigned int size)638 static int dbgp_control_msg(struct ehci_dbgp *dbgp, unsigned int devnum,
639                             int requesttype, int request, int value,
640                             int index, void *data, unsigned int size)
641 {
642     u32 addr, pids, ctrl;
643     struct usb_ctrlrequest req;
644     bool_t read = (requesttype & USB_DIR_IN) != 0;
645     int ret;
646 
647     if ( size > (read ? DBGP_MAX_PACKET : 0) )
648         return -EINVAL;
649 
650     /* Compute the control message */
651     req.bRequestType = requesttype;
652     req.bRequest = request;
653     req.wValue = cpu_to_le16(value);
654     req.wIndex = cpu_to_le16(index);
655     req.wLength = cpu_to_le16(size);
656 
657     pids = DBGP_PID_SET(USB_PID_DATA0, USB_PID_SETUP);
658     addr = DBGP_EPADDR(devnum, 0);
659     ctrl = dbgp_len_update(readl(&dbgp->ehci_debug->control), sizeof(req));
660 
661     /* Send the setup message */
662     dbgp_set_data(dbgp->ehci_debug, &req, sizeof(req));
663     writel(addr, &dbgp->ehci_debug->address);
664     writel(pids, &dbgp->ehci_debug->pids);
665     dbgp_issue_command(dbgp, ctrl, dbgp_ctrl);
666     ret = dbgp_wait_until_done(dbgp, ctrl, DBGP_LOOPS);
667     if ( ret < 0 )
668         return ret;
669 
670     /* Read the result */
671     ret = dbgp_bulk_read(dbgp, devnum, 0, size, &ctrl);
672     if ( !ret )
673         ret = dbgp_wait_until_done(dbgp, ctrl, DBGP_LOOPS);
674     if ( ret > 0 )
675     {
676         if ( size > ret )
677             size = ret;
678         dbgp_get_data(dbgp->ehci_debug, data, size);
679     }
680 
681     return ret;
682 }
683 
__find_dbgp(u8 bus,u8 slot,u8 func)684 static unsigned int __init __find_dbgp(u8 bus, u8 slot, u8 func)
685 {
686     uint32_t class = pci_conf_read32(PCI_SBDF(0, bus, slot, func),
687                                      PCI_CLASS_REVISION);
688 
689     if ( (class >> 8) != PCI_CLASS_SERIAL_USB_EHCI )
690         return 0;
691 
692     return pci_find_cap_offset(0, bus, slot, func, PCI_CAP_ID_EHCI_DEBUG);
693 }
694 
find_dbgp(struct ehci_dbgp * dbgp,unsigned int ehci_num)695 static unsigned int __init find_dbgp(struct ehci_dbgp *dbgp,
696                                      unsigned int ehci_num)
697 {
698     unsigned int bus, slot, func;
699 
700     for ( bus = 0; bus < 256; bus++ )
701     {
702         for ( slot = 0; slot < 32; slot++ )
703         {
704             for ( func = 0; func < 8; func++ )
705             {
706                 unsigned int cap;
707 
708                 if ( !pci_device_detect(0, bus, slot, func) )
709                 {
710                     if ( !func )
711                         break;
712                     continue;
713                 }
714 
715                 cap = __find_dbgp(bus, slot, func);
716                 if ( !cap || ehci_num-- )
717                 {
718                     if ( !func && !(pci_conf_read8(PCI_SBDF(0, bus, slot, func),
719                                                    PCI_HEADER_TYPE) & 0x80) )
720                         break;
721                     continue;
722                 }
723 
724                 dbgp->bus = bus;
725                 dbgp->slot = slot;
726                 dbgp->func = func;
727                 return cap;
728             }
729         }
730     }
731 
732     return 0;
733 }
734 
ehci_dbgp_startup(struct ehci_dbgp * dbgp)735 static int ehci_dbgp_startup(struct ehci_dbgp *dbgp)
736 {
737     u32 ctrl, cmd, status;
738     unsigned int loop;
739 
740     /* Claim ownership, but do not enable yet */
741     ctrl = readl(&dbgp->ehci_debug->control);
742     ctrl |= DBGP_OWNER;
743     ctrl &= ~(DBGP_ENABLED | DBGP_INUSE);
744     writel(ctrl, &dbgp->ehci_debug->control);
745     udelay(1);
746 
747     ehci_dbgp_status(dbgp, "EHCI startup");
748     /* Start the EHCI. */
749     cmd = readl(&dbgp->ehci_regs->command);
750     cmd &= ~(CMD_LRESET | CMD_IAAD | CMD_PSE | CMD_ASE | CMD_RESET);
751     cmd |= CMD_RUN;
752     writel(cmd, &dbgp->ehci_regs->command);
753 
754     /* Ensure everything is routed to the EHCI */
755     writel(FLAG_CF, &dbgp->ehci_regs->configured_flag);
756 
757     /* Wait until the controller is no longer halted. */
758     loop = 1000;
759     do {
760         status = readl(&dbgp->ehci_regs->status);
761         if ( !(status & STS_HALT) )
762             break;
763         udelay(1);
764     } while ( --loop );
765 
766     if ( !loop )
767     {
768         dbgp_printk("EHCI cannot be started\n");
769         return -ENODEV;
770     }
771     dbgp_printk("EHCI started\n");
772 
773     return 0;
774 }
775 
ehci_dbgp_controller_reset(struct ehci_dbgp * dbgp)776 static int ehci_dbgp_controller_reset(struct ehci_dbgp *dbgp)
777 {
778     unsigned int loop = 250 * 1000;
779     u32 cmd;
780 
781     /* Reset the EHCI controller */
782     cmd = readl(&dbgp->ehci_regs->command);
783     cmd |= CMD_RESET;
784     writel(cmd, &dbgp->ehci_regs->command);
785     do {
786         cmd = readl(&dbgp->ehci_regs->command);
787     } while ( (cmd & CMD_RESET) && --loop );
788 
789     if ( !loop )
790     {
791         dbgp_printk("cannot reset EHCI\n");
792         return -1;
793     }
794     ehci_dbgp_status(dbgp, "ehci reset done");
795 
796     return 0;
797 }
798 
ehci_reset_port(struct ehci_dbgp * dbgp,unsigned int port)799 static int ehci_reset_port(struct ehci_dbgp *dbgp, unsigned int port)
800 {
801     u32 portsc, delay_time, delay;
802 
803     ehci_dbgp_status(dbgp, "reset port");
804     /* Reset the USB debug port. */
805     portsc = readl(&dbgp->ehci_regs->port_status[port - 1]);
806     portsc &= ~PORT_PE;
807     portsc |= PORT_RESET;
808     writel(portsc, &dbgp->ehci_regs->port_status[port - 1]);
809 
810     delay = HUB_ROOT_RESET_TIME;
811     for ( delay_time = 0; delay_time < HUB_RESET_TIMEOUT;
812           delay_time += delay )
813     {
814         dbgp_mdelay(delay);
815         portsc = readl(&dbgp->ehci_regs->port_status[port - 1]);
816         if (!(portsc & PORT_RESET))
817             break;
818     }
819 
820     if ( portsc & PORT_RESET )
821     {
822         /* force reset to complete */
823         unsigned int loop = 100 * 1000;
824 
825         writel(portsc & ~(PORT_RWC_BITS | PORT_RESET),
826                &dbgp->ehci_regs->port_status[port - 1]);
827         do {
828             udelay(1);
829             portsc = readl(&dbgp->ehci_regs->port_status[port-1]);
830         } while ( (portsc & PORT_RESET) && --loop );
831     }
832 
833     /* Device went away? */
834     if ( !(portsc & PORT_CONNECT) )
835         return -ENOTCONN;
836 
837     /* bomb out completely if something weird happened */
838     if ( portsc & PORT_CSC )
839         return -EINVAL;
840 
841     /* If we've finished resetting, then break out of the loop */
842     if ( !(portsc & PORT_RESET) && (portsc & PORT_PE) )
843         return 0;
844 
845     return -EBUSY;
846 }
847 
ehci_wait_for_port(struct ehci_dbgp * dbgp,unsigned int port)848 static int ehci_wait_for_port(struct ehci_dbgp *dbgp, unsigned int port)
849 {
850     u32 status;
851     unsigned int reps;
852 
853     for ( reps = 0; reps < 300; reps++ )
854     {
855         status = readl(&dbgp->ehci_regs->status);
856         if ( status & STS_PCD )
857             break;
858         dbgp_mdelay(1);
859     }
860 
861     return ehci_reset_port(dbgp, port) == 0 ? 0 : -ENOTCONN;
862 }
863 
864 /* Return 0 on success
865  * Return -ENODEV for any general failure
866  * Return -EIO if wait for port fails
867  */
ehci_dbgp_external_startup(struct ehci_dbgp * dbgp)868 static int ehci_dbgp_external_startup(struct ehci_dbgp *dbgp)
869 {
870     unsigned int devnum;
871     struct usb_debug_descriptor dbgp_desc;
872     int ret;
873     u32 ctrl, portsc, cmd;
874     unsigned int dbg_port = dbgp->phys_port;
875     unsigned int tries = 3;
876     unsigned int reset_port_tries = 1;
877     bool_t try_hard_once = 1;
878 
879 try_port_reset_again:
880     ret = ehci_dbgp_startup(dbgp);
881     if ( ret )
882         return ret;
883 
884     /* Wait for a device to show up in the debug port */
885     ret = ehci_wait_for_port(dbgp, dbg_port);
886     if ( ret < 0 )
887     {
888         portsc = readl(&dbgp->ehci_regs->port_status[dbg_port - 1]);
889         if ( !(portsc & PORT_CONNECT) && try_hard_once )
890         {
891             /*
892              * Last ditch effort to try to force enable the debug device by
893              * using the packet test EHCI command to try and wake it up.
894              */
895             try_hard_once = 0;
896             cmd = readl(&dbgp->ehci_regs->command);
897             cmd &= ~CMD_RUN;
898             writel(cmd, &dbgp->ehci_regs->command);
899             portsc = readl(&dbgp->ehci_regs->port_status[dbg_port - 1]);
900             portsc |= PORT_TEST_PKT;
901             writel(portsc, &dbgp->ehci_regs->port_status[dbg_port - 1]);
902             ehci_dbgp_status(dbgp, "Trying to force debug port online");
903             mdelay(50);
904             ehci_dbgp_controller_reset(dbgp);
905             goto try_port_reset_again;
906         }
907         else if ( reset_port_tries-- )
908             goto try_port_reset_again;
909         dbgp_printk("no device found in debug port\n");
910         return -EIO;
911     }
912     ehci_dbgp_status(dbgp, "wait for port done");
913 
914     /* Enable the debug port */
915     ctrl = readl(&dbgp->ehci_debug->control);
916     ctrl |= DBGP_CLAIM;
917     writel(ctrl, &dbgp->ehci_debug->control);
918     ctrl = readl(&dbgp->ehci_debug->control);
919     if ( (ctrl & DBGP_CLAIM) != DBGP_CLAIM )
920     {
921         dbgp_printk("no device in debug port\n");
922         writel(ctrl & ~DBGP_CLAIM, &dbgp->ehci_debug->control);
923         return -ENODEV;
924     }
925     ehci_dbgp_status(dbgp, "debug port enabled");
926 
927     /* Completely transfer the debug device to the debug controller */
928     portsc = readl(&dbgp->ehci_regs->port_status[dbg_port - 1]);
929     portsc &= ~PORT_PE;
930     writel(portsc, &dbgp->ehci_regs->port_status[dbg_port - 1]);
931 
932     dbgp_mdelay(100);
933 
934 try_again:
935     /* Find the debug device and make it device number 127 */
936     for ( devnum = 0; devnum <= 127; devnum++ )
937     {
938         ret = dbgp_control_msg(dbgp, devnum,
939                                USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
940                                USB_REQ_GET_DESCRIPTOR, (USB_DT_DEBUG << 8), 0,
941                                &dbgp_desc, sizeof(dbgp_desc));
942         if ( ret > 0 )
943             break;
944     }
945     if ( devnum > 127 )
946     {
947         dbgp_printk("could not find attached debug device\n");
948         goto err;
949     }
950     dbgp->out.endpoint = dbgp_desc.bDebugOutEndpoint;
951     dbgp->in.endpoint = dbgp_desc.bDebugInEndpoint;
952 
953     /* Move the device to 127 if it isn't already there. */
954     if ( devnum != USB_DEBUG_DEVNUM )
955     {
956         ret = dbgp_control_msg(dbgp, devnum,
957                                USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
958                                USB_REQ_SET_ADDRESS, USB_DEBUG_DEVNUM, 0, NULL, 0);
959         if ( ret < 0 )
960         {
961             dbgp_printk("could not move attached device to %d\n",
962                         USB_DEBUG_DEVNUM);
963             goto err;
964         }
965         devnum = USB_DEBUG_DEVNUM;
966         dbgp_printk("debug device renamed to 127\n");
967     }
968 
969     /* Enable the debug interface */
970     ret = dbgp_control_msg(dbgp, USB_DEBUG_DEVNUM,
971                            USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
972                            USB_REQ_SET_FEATURE, USB_DEVICE_DEBUG_MODE,
973                            0, NULL, 0);
974     if ( ret < 0 )
975     {
976         dbgp_printk("could not enable the debug device\n");
977         goto err;
978     }
979     dbgp_printk("debug interface enabled\n");
980 
981     /* Perform a small write to get the even/odd data state in sync. */
982     ret = dbgp_bulk_write(dbgp, USB_DEBUG_DEVNUM, dbgp->out.endpoint,
983                           "\n", 1, &ctrl);
984     if ( !ret )
985         ret = dbgp_wait_until_done(dbgp, ctrl, DBGP_LOOPS);
986     if ( ret < 0 )
987     {
988         dbgp_printk("dbgp_bulk_write failed: %d\n", ret);
989         goto err;
990     }
991     dbgp_printk("small write done\n");
992     dbgp->state = dbgp_idle;
993 
994     return 0;
995 err:
996     if ( tries-- )
997         goto try_again;
998     return -ENODEV;
999 }
1000 
1001 typedef void (*set_debug_port_t)(struct ehci_dbgp *, unsigned int);
1002 
default_set_debug_port(struct ehci_dbgp * dbgp,unsigned int port)1003 static void default_set_debug_port(struct ehci_dbgp *dbgp, unsigned int port)
1004 {
1005 }
1006 
1007 static set_debug_port_t __read_mostly set_debug_port = default_set_debug_port;
1008 
nvidia_set_debug_port(struct ehci_dbgp * dbgp,unsigned int port)1009 static void nvidia_set_debug_port(struct ehci_dbgp *dbgp, unsigned int port)
1010 {
1011     uint32_t dword = pci_conf_read32(PCI_SBDF(0, dbgp->bus, dbgp->slot,
1012                                               dbgp->func), 0x74);
1013 
1014     dword &= ~(0x0f << 12);
1015     dword |= (port & 0x0f) << 12;
1016     pci_conf_write32(PCI_SBDF(0, dbgp->bus, dbgp->slot, dbgp->func), 0x74,
1017                      dword);
1018     dbgp_printk("set debug port to %u\n", port);
1019 }
1020 
detect_set_debug_port(struct ehci_dbgp * dbgp)1021 static void __init detect_set_debug_port(struct ehci_dbgp *dbgp)
1022 {
1023     if ( pci_conf_read16(PCI_SBDF(0, dbgp->bus, dbgp->slot, dbgp->func),
1024                          PCI_VENDOR_ID) == 0x10de )
1025     {
1026         dbgp_printk("using nvidia set_debug_port\n");
1027         set_debug_port = nvidia_set_debug_port;
1028     }
1029 }
1030 
1031 /*
1032  * The code in ehci_dbgp_bios_handoff() is derived from the USB PCI
1033  * quirk initialization in Linux.
1034  */
1035 #define EHCI_USBLEGSUP_BIOS    (1 << 16) /* BIOS semaphore */
1036 #define EHCI_USBLEGCTLSTS      4        /* legacy control/status */
ehci_dbgp_bios_handoff(struct ehci_dbgp * dbgp,u32 hcc_params)1037 static void ehci_dbgp_bios_handoff(struct ehci_dbgp *dbgp, u32 hcc_params)
1038 {
1039     u32 cap;
1040     unsigned int offset = HCC_EXT_CAPS(hcc_params);
1041     int msec;
1042 
1043     if ( !offset )
1044         return;
1045 
1046     cap = pci_conf_read32(PCI_SBDF(0, dbgp->bus, dbgp->slot, dbgp->func),
1047                           offset);
1048     dbgp_printk("dbgp: EHCI BIOS state %08x\n", cap);
1049 
1050     if ( (cap & 0xff) == 1 && (cap & EHCI_USBLEGSUP_BIOS) )
1051     {
1052         dbgp_printk("dbgp: BIOS handoff\n");
1053         pci_conf_write8(PCI_SBDF(0, dbgp->bus, dbgp->slot, dbgp->func),
1054                         offset + 3, 1);
1055     }
1056 
1057     /* if boot firmware now owns EHCI, spin till it hands it over. */
1058     msec = 1000;
1059     while ( (cap & EHCI_USBLEGSUP_BIOS) && (msec > 0) )
1060     {
1061         mdelay(10);
1062         msec -= 10;
1063         cap = pci_conf_read32(PCI_SBDF(0, dbgp->bus, dbgp->slot, dbgp->func),
1064                               offset);
1065     }
1066 
1067     if ( cap & EHCI_USBLEGSUP_BIOS )
1068     {
1069         /* well, possibly buggy BIOS... try to shut it down,
1070          * and hope nothing goes too wrong */
1071         dbgp_printk("dbgp: BIOS handoff failed: %08x\n", cap);
1072         pci_conf_write8(PCI_SBDF(0, dbgp->bus, dbgp->slot, dbgp->func),
1073                         offset + 2, 0);
1074     }
1075 
1076     /* just in case, always disable EHCI SMIs */
1077     pci_conf_write8(PCI_SBDF(0, dbgp->bus, dbgp->slot, dbgp->func),
1078                     offset + EHCI_USBLEGCTLSTS, 0);
1079 }
1080 
ehci_dbgp_setup(struct ehci_dbgp * dbgp)1081 static int ehci_dbgp_setup(struct ehci_dbgp *dbgp)
1082 {
1083     u32 ctrl, portsc, hcs_params;
1084     unsigned int i, debug_port, new_debug_port = 0, n_ports;
1085     unsigned int port_map_tried, playtimes = 3;
1086     int ret;
1087 
1088     ehci_dbgp_bios_handoff(dbgp, readl(&dbgp->ehci_caps->hcc_params));
1089 
1090 try_next_time:
1091     port_map_tried = 0;
1092 
1093 try_next_port:
1094 
1095     hcs_params = readl(&dbgp->ehci_caps->hcs_params);
1096     debug_port = HCS_DEBUG_PORT(hcs_params);
1097     dbgp->phys_port = debug_port;
1098     n_ports = HCS_N_PORTS(hcs_params);
1099 
1100     dbgp_printk("debug_port: %u\n", debug_port);
1101     dbgp_printk("n_ports:    %u\n", n_ports);
1102     ehci_dbgp_status(dbgp, "");
1103 
1104     if ( n_ports == 0 )
1105         return -1;
1106 
1107     for ( i = 1; i <= n_ports; i++ )
1108     {
1109         portsc = readl(&dbgp->ehci_regs->port_status[i-1]);
1110         dbgp_printk("portstatus%d: %08x\n", i, portsc);
1111     }
1112 
1113     if ( port_map_tried && (new_debug_port != debug_port) )
1114     {
1115         if ( --playtimes )
1116         {
1117             set_debug_port(dbgp, new_debug_port);
1118             goto try_next_time;
1119         }
1120         return -1;
1121     }
1122 
1123     /* Only reset the controller if it is not already in the
1124      * configured state */
1125     if ( readl(&dbgp->ehci_regs->configured_flag) & FLAG_CF )
1126         ehci_dbgp_status(dbgp, "ehci skip - already configured");
1127     else if ( ehci_dbgp_controller_reset(dbgp) != 0 )
1128         return -1;
1129 
1130     ret = ehci_dbgp_external_startup(dbgp);
1131     if (ret == -EIO)
1132         goto next_debug_port;
1133 
1134     if ( ret < 0 )
1135     {
1136         /* Things didn't work so remove my claim */
1137         ctrl = readl(&dbgp->ehci_debug->control);
1138         ctrl &= ~(DBGP_CLAIM | DBGP_OUT);
1139         writel(ctrl, &dbgp->ehci_debug->control);
1140         return -1;
1141     }
1142 
1143     return 0;
1144 
1145 next_debug_port:
1146     port_map_tried |= 1 << (debug_port - 1);
1147     new_debug_port = (debug_port % n_ports) + 1;
1148     if ( port_map_tried != ((1 << n_ports) - 1) )
1149     {
1150         set_debug_port(dbgp, new_debug_port);
1151         goto try_next_port;
1152     }
1153     if ( --playtimes )
1154     {
1155         set_debug_port(dbgp, new_debug_port);
1156         goto try_next_time;
1157     }
1158 
1159     return -1;
1160 }
1161 
_ehci_dbgp_flush(struct ehci_dbgp * dbgp)1162 static inline void _ehci_dbgp_flush(struct ehci_dbgp *dbgp)
1163 {
1164     if ( dbgp_bulk_write(dbgp, USB_DEBUG_DEVNUM, dbgp->out.endpoint,
1165                          dbgp->out.buf, dbgp->out.chunk, NULL) )
1166         BUG();
1167     dbgp->out.chunk = 0;
1168 }
1169 
ehci_dbgp_flush(struct serial_port * port)1170 static void ehci_dbgp_flush(struct serial_port *port)
1171 {
1172     struct ehci_dbgp *dbgp = port->uart;
1173     s_time_t goal;
1174 
1175     if ( !dbgp->out.chunk || !dbgp->ehci_debug || dbgp->state == dbgp_unsafe )
1176         return;
1177 
1178     if ( dbgp->state == dbgp_idle || !port->sync )
1179         dbgp_check_for_completion(dbgp, 1, NULL);
1180     else
1181         dbgp_wait_until_complete(dbgp, NULL);
1182 
1183     if ( dbgp->state == dbgp_idle )
1184     {
1185         _ehci_dbgp_flush(dbgp);
1186 
1187         if ( port->sync )
1188         {
1189             dbgp_wait_until_complete(dbgp, NULL);
1190             return;
1191         }
1192     }
1193 
1194     goal = NOW() + MICROSECS(DBGP_CHECK_INTERVAL);
1195     if ( dbgp->timer.expires > goal )
1196        set_timer(&dbgp->timer, goal);
1197 }
1198 
ehci_dbgp_putc(struct serial_port * port,char c)1199 static void ehci_dbgp_putc(struct serial_port *port, char c)
1200 {
1201     struct ehci_dbgp *dbgp = port->uart;
1202 
1203     if ( unlikely(dbgp->out.chunk >= DBGP_MAX_PACKET) )
1204         return;
1205 
1206     dbgp->out.buf[dbgp->out.chunk++] = c;
1207 
1208     if ( dbgp->out.chunk == DBGP_MAX_PACKET )
1209         ehci_dbgp_flush(port);
1210 }
1211 
ehci_dbgp_tx_ready(struct serial_port * port)1212 static int ehci_dbgp_tx_ready(struct serial_port *port)
1213 {
1214     struct ehci_dbgp *dbgp = port->uart;
1215 
1216     if ( unlikely(!dbgp->ehci_debug) || unlikely(dbgp->state == dbgp_unsafe) )
1217         return port->sync || port->tx_log_everything || !port->txbuf;
1218 
1219     if ( dbgp->out.chunk == DBGP_MAX_PACKET )
1220         ehci_dbgp_flush(port);
1221     else
1222         dbgp_check_for_completion(dbgp, 1, NULL);
1223 
1224     if ( dbgp->state != dbgp_idle && dbgp->out.chunk >= DBGP_MAX_PACKET )
1225         return 0;
1226 
1227     return DBGP_MAX_PACKET - dbgp->out.chunk +
1228            (dbgp->state == dbgp_idle) * DBGP_MAX_PACKET;
1229 }
1230 
ehci_dbgp_getc(struct serial_port * port,char * pc)1231 static int ehci_dbgp_getc(struct serial_port *port, char *pc)
1232 {
1233     struct ehci_dbgp *dbgp = port->uart;
1234 
1235     if ( !dbgp->in.chunk )
1236         return 0;
1237 
1238     *pc = *dbgp->in.buf;
1239     if ( --dbgp->in.chunk )
1240         memmove(dbgp->in.buf, dbgp->in.buf + 1, dbgp->in.chunk);
1241 
1242     return 1;
1243 }
1244 
1245 /* Safe: ehci_dbgp_poll() runs as timer handler, so not reentrant. */
1246 static struct serial_port *poll_port;
1247 
_ehci_dbgp_poll(struct cpu_user_regs * regs)1248 static void _ehci_dbgp_poll(struct cpu_user_regs *regs)
1249 {
1250     struct serial_port *port = poll_port;
1251     struct ehci_dbgp *dbgp = port->uart;
1252     unsigned long flags;
1253     unsigned int timeout = MICROSECS(DBGP_CHECK_INTERVAL);
1254     bool_t empty = 0;
1255 
1256     if ( !dbgp->ehci_debug )
1257         return;
1258 
1259     if ( spin_trylock_irqsave(&port->tx_lock, flags) )
1260     {
1261         if ( dbgp->state != dbgp_unsafe )
1262             dbgp_check_for_completion(dbgp, DBGP_CHECK_INTERVAL, NULL);
1263         if ( dbgp->state == dbgp_idle && dbgp->out.chunk )
1264             _ehci_dbgp_flush(dbgp);
1265         if ( dbgp->state == dbgp_idle || dbgp->out.chunk < DBGP_MAX_PACKET )
1266             empty = 1;
1267         spin_unlock_irqrestore(&port->tx_lock, flags);
1268     }
1269 
1270     if ( dbgp->in.chunk )
1271         serial_rx_interrupt(port, regs);
1272 
1273     if ( empty )
1274         serial_tx_interrupt(port, regs);
1275 
1276     if ( spin_trylock_irqsave(&port->tx_lock, flags) )
1277     {
1278         if ( dbgp->state == dbgp_idle && !dbgp->in.chunk &&
1279              !dbgp->out.chunk && port->txbufp == port->txbufc )
1280         {
1281             if ( dbgp_bulk_read(dbgp, USB_DEBUG_DEVNUM, dbgp->in.endpoint,
1282                                 DBGP_MAX_PACKET, NULL) )
1283                 BUG();
1284             timeout = MILLISECS(DBGP_IDLE_INTERVAL);
1285         }
1286         spin_unlock_irqrestore(&port->tx_lock, flags);
1287     }
1288 
1289     set_timer(&dbgp->timer, NOW() + timeout);
1290 }
1291 
ehci_dbgp_poll(void * data)1292 static void ehci_dbgp_poll(void *data)
1293 {
1294     poll_port = data;
1295 #ifdef run_in_exception_handler
1296     run_in_exception_handler(_ehci_dbgp_poll);
1297 #else
1298     _ehci_dbgp_poll(guest_cpu_user_regs());
1299 #endif
1300 }
1301 
ehci_dbgp_setup_preirq(struct ehci_dbgp * dbgp)1302 static bool_t ehci_dbgp_setup_preirq(struct ehci_dbgp *dbgp)
1303 {
1304     if ( !ehci_dbgp_setup(dbgp) )
1305         return 1;
1306 
1307     dbgp_printk("ehci_dbgp_setup failed\n");
1308     dbgp->ehci_debug = NULL;
1309     return 0;
1310 }
1311 
ehci_dbgp_init_preirq(struct serial_port * port)1312 static void __init ehci_dbgp_init_preirq(struct serial_port *port)
1313 {
1314     struct ehci_dbgp *dbgp = port->uart;
1315     u32 debug_port, offset;
1316     void __iomem *ehci_bar;
1317 
1318     debug_port = pci_conf_read32(PCI_SBDF(0, dbgp->bus, dbgp->slot, dbgp->func),
1319                                  dbgp->cap);
1320     offset = (debug_port >> 16) & 0xfff;
1321 
1322     /* double check if the mem space is enabled */
1323     dbgp->pci_cr = pci_conf_read8(PCI_SBDF(0, dbgp->bus, dbgp->slot,
1324                                            dbgp->func),
1325                                   PCI_COMMAND);
1326     if ( !(dbgp->pci_cr & PCI_COMMAND_MEMORY) )
1327     {
1328         dbgp->pci_cr |= PCI_COMMAND_MEMORY;
1329         pci_conf_write16(PCI_SBDF(0, dbgp->bus, dbgp->slot, dbgp->func),
1330                          PCI_COMMAND, dbgp->pci_cr);
1331         dbgp_printk("MMIO for EHCI enabled\n");
1332     }
1333 
1334     /*
1335      * FIXME I don't have the bar size so just guess PAGE_SIZE is more
1336      * than enough.  1k is the biggest that was seen.
1337      */
1338     set_fixmap_nocache(FIX_EHCI_DBGP, dbgp->bar_val);
1339     ehci_bar = fix_to_virt(FIX_EHCI_DBGP);
1340     ehci_bar += dbgp->bar_val & ~PAGE_MASK;
1341     dbgp_printk("ehci_bar: %p\n", ehci_bar);
1342 
1343     dbgp->ehci_caps = ehci_bar;
1344     dbgp->ehci_regs = ehci_bar +
1345                       HC_LENGTH(readl(&dbgp->ehci_caps->hc_capbase));
1346     dbgp->ehci_debug = ehci_bar + offset;
1347 
1348     detect_set_debug_port(dbgp);
1349 
1350     if ( ehci_dbgp_setup_preirq(dbgp) )
1351         ehci_dbgp_status(dbgp, "ehci_dbgp_init_preirq complete");
1352 
1353     dbgp->lock = &port->tx_lock;
1354 }
1355 
ehci_dbgp_setup_postirq(struct ehci_dbgp * dbgp)1356 static void ehci_dbgp_setup_postirq(struct ehci_dbgp *dbgp)
1357 {
1358     set_timer(&dbgp->timer, NOW() + MILLISECS(1));
1359 }
1360 
ehci_dbgp_init_postirq(struct serial_port * port)1361 static void __init ehci_dbgp_init_postirq(struct serial_port *port)
1362 {
1363     struct ehci_dbgp *dbgp = port->uart;
1364 
1365     if ( !dbgp->ehci_debug )
1366         return;
1367 
1368     serial_async_transmit(port);
1369 
1370     init_timer(&dbgp->timer, ehci_dbgp_poll, port, 0);
1371 
1372     ehci_dbgp_setup_postirq(dbgp);
1373 
1374     pci_hide_device(0, dbgp->bus, PCI_DEVFN(dbgp->slot, dbgp->func));
1375 }
1376 
ehci_dbgp_check_release(struct ehci_dbgp * dbgp)1377 static int ehci_dbgp_check_release(struct ehci_dbgp *dbgp)
1378 {
1379     struct ehci_dbg_port __iomem *ehci_debug = dbgp->ehci_debug;
1380     u32 ctrl;
1381     unsigned int i;
1382 
1383     if ( !ehci_debug )
1384         return 0;
1385 
1386     for ( i = 0; i < DBGP_MAX_PACKET; ++i )
1387         if ( dbgp->out.buf[i] )
1388             return 1;
1389 
1390     /*
1391      * This means the console is not initialized, or should get shutdown
1392      * so as to allow for reuse of the USB device, which means it is time
1393      * to shutdown the USB debug port.
1394      */
1395     printk(XENLOG_INFO "Releasing EHCI debug port at %02x:%02x.%u\n",
1396            dbgp->bus, dbgp->slot, dbgp->func);
1397 
1398     if ( dbgp->timer.function )
1399         kill_timer(&dbgp->timer);
1400     dbgp->ehci_debug = NULL;
1401 
1402     ctrl = readl(&ehci_debug->control);
1403     if ( ctrl & DBGP_ENABLED )
1404     {
1405         ctrl &= ~DBGP_CLAIM;
1406         writel(ctrl, &ehci_debug->control);
1407     }
1408 
1409     return 0;
1410 }
1411 
ehci_dbgp_endboot(struct serial_port * port)1412 static void __init ehci_dbgp_endboot(struct serial_port *port)
1413 {
1414     ehci_dbgp_check_release(port->uart);
1415 }
1416 
ehci_dbgp_suspend(struct serial_port * port)1417 static void ehci_dbgp_suspend(struct serial_port *port)
1418 {
1419     struct ehci_dbgp *dbgp = port->uart;
1420 
1421     if ( !dbgp->ehci_debug )
1422         return;
1423 
1424     stop_timer(&dbgp->timer);
1425     dbgp->timer.expires = 0;
1426 
1427     dbgp->pci_cr = pci_conf_read16(PCI_SBDF(0, dbgp->bus, dbgp->slot,
1428                                             dbgp->func),
1429                                    PCI_COMMAND);
1430 
1431     dbgp->state = dbgp_unsafe;
1432 }
1433 
ehci_dbgp_resume(struct serial_port * port)1434 static void ehci_dbgp_resume(struct serial_port *port)
1435 {
1436     struct ehci_dbgp *dbgp = port->uart;
1437 
1438     if ( !dbgp->ehci_debug )
1439         return;
1440 
1441     pci_conf_write32(PCI_SBDF(0, dbgp->bus, dbgp->slot, dbgp->func), dbgp->bar,
1442                      dbgp->bar_val);
1443     pci_conf_write16(PCI_SBDF(0, dbgp->bus, dbgp->slot, dbgp->func),
1444                      PCI_COMMAND, dbgp->pci_cr);
1445 
1446     ehci_dbgp_setup_preirq(dbgp);
1447     ehci_dbgp_setup_postirq(dbgp);
1448 }
1449 
1450 static struct uart_driver __read_mostly ehci_dbgp_driver = {
1451     .init_preirq  = ehci_dbgp_init_preirq,
1452     .init_postirq = ehci_dbgp_init_postirq,
1453     .endboot      = ehci_dbgp_endboot,
1454     .suspend      = ehci_dbgp_suspend,
1455     .resume       = ehci_dbgp_resume,
1456     .tx_ready     = ehci_dbgp_tx_ready,
1457     .putc         = ehci_dbgp_putc,
1458     .flush        = ehci_dbgp_flush,
1459     .getc         = ehci_dbgp_getc
1460 };
1461 
1462 static struct ehci_dbgp ehci_dbgp = { .state = dbgp_unsafe, .phys_port = 1 };
1463 
1464 static char __initdata opt_dbgp[30];
1465 string_param("dbgp", opt_dbgp);
1466 
ehci_dbgp_init(void)1467 void __init ehci_dbgp_init(void)
1468 {
1469     struct ehci_dbgp *dbgp = &ehci_dbgp;
1470     u32 debug_port, offset, bar_val;
1471     const char *e;
1472 
1473     if ( strncmp(opt_dbgp, "ehci", 4) )
1474         return;
1475 
1476     if ( isdigit(opt_dbgp[4]) || !opt_dbgp[4] )
1477     {
1478         unsigned int num = 0;
1479 
1480         if ( opt_dbgp[4] )
1481             simple_strtoul(opt_dbgp + 4, &e, 10);
1482 
1483         dbgp->cap = find_dbgp(dbgp, num);
1484         if ( !dbgp->cap )
1485             return;
1486 
1487         dbgp_printk("Found EHCI debug port on %02x:%02x.%u\n",
1488                     dbgp->bus, dbgp->slot, dbgp->func);
1489     }
1490     else if ( strncmp(opt_dbgp + 4, "@pci", 4) == 0 )
1491     {
1492         unsigned int bus, slot, func;
1493 
1494         e = parse_pci(opt_dbgp + 8, NULL, &bus, &slot, &func);
1495         if ( !e || *e )
1496             return;
1497 
1498         dbgp->bus = bus;
1499         dbgp->slot = slot;
1500         dbgp->func = func;
1501 
1502         if ( !pci_device_detect(0, bus, slot, func) )
1503             return;
1504 
1505         dbgp->cap = __find_dbgp(bus, slot, func);
1506         if ( !dbgp->cap )
1507             return;
1508 
1509         dbgp_printk("Using EHCI debug port on %02x:%02x.%u\n",
1510                     bus, slot, func);
1511     }
1512     else
1513         return;
1514 
1515     debug_port = pci_conf_read32(PCI_SBDF(0, dbgp->bus, dbgp->slot, dbgp->func),
1516                                  dbgp->cap);
1517     dbgp->bar = (debug_port >> 29) & 0x7;
1518     dbgp->bar = ((dbgp->bar - 1) * 4) + PCI_BASE_ADDRESS_0;
1519     offset = (debug_port >> 16) & 0xfff;
1520     dbgp_printk("bar: %02x offset: %03x\n", dbgp->bar, offset);
1521     if ( dbgp->bar < PCI_BASE_ADDRESS_0 || dbgp->bar > PCI_BASE_ADDRESS_5 )
1522     {
1523         dbgp_printk("unsupported/invalid bar\n");
1524         return;
1525     }
1526 
1527     dbgp->bar_val = bar_val = pci_conf_read32(PCI_SBDF(0, dbgp->bus, dbgp->slot,
1528                                                        dbgp->func), dbgp->bar);
1529     dbgp_printk("bar_val: %08x\n", bar_val);
1530     if ( bar_val & ~PCI_BASE_ADDRESS_MEM_MASK )
1531     {
1532         dbgp_printk("only simple 32-bit MMIO BARs supported\n");
1533         return;
1534     }
1535     bar_val &= PCI_BASE_ADDRESS_MEM_MASK;
1536     if ( !bar_val || !(bar_val + (bar_val & -bar_val)) )
1537     {
1538         dbgp_printk("firmware initialization of MMIO BAR required\n");
1539         return;
1540     }
1541 
1542     serial_register_uart(SERHND_DBGP, &ehci_dbgp_driver, dbgp);
1543 }
1544 
dbgp_op(const struct physdev_dbgp_op * op)1545 int dbgp_op(const struct physdev_dbgp_op *op)
1546 {
1547     if ( !ehci_dbgp.ehci_debug )
1548         return 0;
1549 
1550     switch ( op->bus )
1551     {
1552     case PHYSDEVOP_DBGP_BUS_UNKNOWN:
1553         break;
1554     case PHYSDEVOP_DBGP_BUS_PCI:
1555         if ( op->u.pci.seg || ehci_dbgp.bus != op->u.pci.bus ||
1556             PCI_DEVFN(ehci_dbgp.slot, ehci_dbgp.func) != op->u.pci.devfn )
1557     default:
1558             return 0;
1559         break;
1560     }
1561 
1562     switch ( op->op )
1563     {
1564     case PHYSDEVOP_DBGP_RESET_PREPARE:
1565         spin_lock_irq(ehci_dbgp.lock);
1566         ehci_dbgp.state = dbgp_unsafe;
1567         dbgp_wait_until_complete(&ehci_dbgp, NULL);
1568         spin_unlock_irq(ehci_dbgp.lock);
1569 
1570         return ehci_dbgp_check_release(&ehci_dbgp);
1571 
1572     case PHYSDEVOP_DBGP_RESET_DONE:
1573         return ehci_dbgp_external_startup(&ehci_dbgp) ?: 1;
1574     }
1575 
1576     return -ENOSYS;
1577 }
1578