1 /*
2 * pti.c - PTI driver for cJTAG data extration
3 *
4 * Copyright (C) Intel 2010
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
16 *
17 * The PTI (Parallel Trace Interface) driver directs trace data routed from
18 * various parts in the system out through the Intel Penwell PTI port and
19 * out of the mobile device for analysis with a debugging tool
20 * (Lauterbach, Fido). This is part of a solution for the MIPI P1149.7,
21 * compact JTAG, standard.
22 */
23
24 #include <linux/init.h>
25 #include <linux/sched.h>
26 #include <linux/interrupt.h>
27 #include <linux/console.h>
28 #include <linux/kernel.h>
29 #include <linux/module.h>
30 #include <linux/tty.h>
31 #include <linux/tty_driver.h>
32 #include <linux/pci.h>
33 #include <linux/mutex.h>
34 #include <linux/miscdevice.h>
35 #include <linux/intel-pti.h>
36 #include <linux/slab.h>
37 #include <linux/uaccess.h>
38
39 #define DRIVERNAME "pti"
40 #define PCINAME "pciPTI"
41 #define TTYNAME "ttyPTI"
42 #define CHARNAME "pti"
43 #define PTITTY_MINOR_START 0
44 #define PTITTY_MINOR_NUM 2
45 #define MAX_APP_IDS 16 /* 128 channel ids / u8 bit size */
46 #define MAX_OS_IDS 16 /* 128 channel ids / u8 bit size */
47 #define MAX_MODEM_IDS 16 /* 128 channel ids / u8 bit size */
48 #define MODEM_BASE_ID 71 /* modem master ID address */
49 #define CONTROL_ID 72 /* control master ID address */
50 #define CONSOLE_ID 73 /* console master ID address */
51 #define OS_BASE_ID 74 /* base OS master ID address */
52 #define APP_BASE_ID 80 /* base App master ID address */
53 #define CONTROL_FRAME_LEN 32 /* PTI control frame maximum size */
54 #define USER_COPY_SIZE 8192 /* 8Kb buffer for user space copy */
55 #define APERTURE_14 0x3800000 /* offset to first OS write addr */
56 #define APERTURE_LEN 0x400000 /* address length */
57
58 struct pti_tty {
59 struct pti_masterchannel *mc;
60 };
61
62 struct pti_dev {
63 struct tty_port port[PTITTY_MINOR_NUM];
64 unsigned long pti_addr;
65 unsigned long aperture_base;
66 void __iomem *pti_ioaddr;
67 u8 ia_app[MAX_APP_IDS];
68 u8 ia_os[MAX_OS_IDS];
69 u8 ia_modem[MAX_MODEM_IDS];
70 };
71
72 /*
73 * This protects access to ia_app, ia_os, and ia_modem,
74 * which keeps track of channels allocated in
75 * an aperture write id.
76 */
77 static DEFINE_MUTEX(alloclock);
78
79 static const struct pci_device_id pci_ids[] = {
80 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x82B)},
81 {0}
82 };
83
84 static struct tty_driver *pti_tty_driver;
85 static struct pti_dev *drv_data;
86
87 static unsigned int pti_console_channel;
88 static unsigned int pti_control_channel;
89
90 /**
91 * pti_write_to_aperture()- The private write function to PTI HW.
92 *
93 * @mc: The 'aperture'. It's part of a write address that holds
94 * a master and channel ID.
95 * @buf: Data being written to the HW that will ultimately be seen
96 * in a debugging tool (Fido, Lauterbach).
97 * @len: Size of buffer.
98 *
99 * Since each aperture is specified by a unique
100 * master/channel ID, no two processes will be writing
101 * to the same aperture at the same time so no lock is required. The
102 * PTI-Output agent will send these out in the order that they arrived, and
103 * thus, it will intermix these messages. The debug tool can then later
104 * regroup the appropriate message segments together reconstituting each
105 * message.
106 */
pti_write_to_aperture(struct pti_masterchannel * mc,u8 * buf,int len)107 static void pti_write_to_aperture(struct pti_masterchannel *mc,
108 u8 *buf,
109 int len)
110 {
111 int dwordcnt;
112 int final;
113 int i;
114 u32 ptiword;
115 u32 __iomem *aperture;
116 u8 *p = buf;
117
118 /*
119 * calculate the aperture offset from the base using the master and
120 * channel id's.
121 */
122 aperture = drv_data->pti_ioaddr + (mc->master << 15)
123 + (mc->channel << 8);
124
125 dwordcnt = len >> 2;
126 final = len - (dwordcnt << 2); /* final = trailing bytes */
127 if (final == 0 && dwordcnt != 0) { /* always need a final dword */
128 final += 4;
129 dwordcnt--;
130 }
131
132 for (i = 0; i < dwordcnt; i++) {
133 ptiword = be32_to_cpu(*(u32 *)p);
134 p += 4;
135 iowrite32(ptiword, aperture);
136 }
137
138 aperture += PTI_LASTDWORD_DTS; /* adding DTS signals that is EOM */
139
140 ptiword = 0;
141 for (i = 0; i < final; i++)
142 ptiword |= *p++ << (24-(8*i));
143
144 iowrite32(ptiword, aperture);
145 return;
146 }
147
148 /**
149 * pti_control_frame_built_and_sent()- control frame build and send function.
150 *
151 * @mc: The master / channel structure on which the function
152 * built a control frame.
153 * @thread_name: The thread name associated with the master / channel or
154 * 'NULL' if using the 'current' global variable.
155 *
156 * To be able to post process the PTI contents on host side, a control frame
157 * is added before sending any PTI content. So the host side knows on
158 * each PTI frame the name of the thread using a dedicated master / channel.
159 * The thread name is retrieved from 'current' global variable if 'thread_name'
160 * is 'NULL', else it is retrieved from 'thread_name' parameter.
161 * This function builds this frame and sends it to a master ID CONTROL_ID.
162 * The overhead is only 32 bytes since the driver only writes to HW
163 * in 32 byte chunks.
164 */
pti_control_frame_built_and_sent(struct pti_masterchannel * mc,const char * thread_name)165 static void pti_control_frame_built_and_sent(struct pti_masterchannel *mc,
166 const char *thread_name)
167 {
168 /*
169 * Since we access the comm member in current's task_struct, we only
170 * need to be as large as what 'comm' in that structure is.
171 */
172 char comm[TASK_COMM_LEN];
173 struct pti_masterchannel mccontrol = {.master = CONTROL_ID,
174 .channel = 0};
175 const char *thread_name_p;
176 const char *control_format = "%3d %3d %s";
177 u8 control_frame[CONTROL_FRAME_LEN];
178
179 if (!thread_name) {
180 if (!in_interrupt())
181 get_task_comm(comm, current);
182 else
183 strncpy(comm, "Interrupt", TASK_COMM_LEN);
184
185 /* Absolutely ensure our buffer is zero terminated. */
186 comm[TASK_COMM_LEN-1] = 0;
187 thread_name_p = comm;
188 } else {
189 thread_name_p = thread_name;
190 }
191
192 mccontrol.channel = pti_control_channel;
193 pti_control_channel = (pti_control_channel + 1) & 0x7f;
194
195 snprintf(control_frame, CONTROL_FRAME_LEN, control_format, mc->master,
196 mc->channel, thread_name_p);
197 pti_write_to_aperture(&mccontrol, control_frame, strlen(control_frame));
198 }
199
200 /**
201 * pti_write_full_frame_to_aperture()- high level function to
202 * write to PTI.
203 *
204 * @mc: The 'aperture'. It's part of a write address that holds
205 * a master and channel ID.
206 * @buf: Data being written to the HW that will ultimately be seen
207 * in a debugging tool (Fido, Lauterbach).
208 * @len: Size of buffer.
209 *
210 * All threads sending data (either console, user space application, ...)
211 * are calling the high level function to write to PTI meaning that it is
212 * possible to add a control frame before sending the content.
213 */
pti_write_full_frame_to_aperture(struct pti_masterchannel * mc,const unsigned char * buf,int len)214 static void pti_write_full_frame_to_aperture(struct pti_masterchannel *mc,
215 const unsigned char *buf,
216 int len)
217 {
218 pti_control_frame_built_and_sent(mc, NULL);
219 pti_write_to_aperture(mc, (u8 *)buf, len);
220 }
221
222 /**
223 * get_id()- Allocate a master and channel ID.
224 *
225 * @id_array: an array of bits representing what channel
226 * id's are allocated for writing.
227 * @max_ids: The max amount of available write IDs to use.
228 * @base_id: The starting SW channel ID, based on the Intel
229 * PTI arch.
230 * @thread_name: The thread name associated with the master / channel or
231 * 'NULL' if using the 'current' global variable.
232 *
233 * Returns:
234 * pti_masterchannel struct with master, channel ID address
235 * 0 for error
236 *
237 * Each bit in the arrays ia_app and ia_os correspond to a master and
238 * channel id. The bit is one if the id is taken and 0 if free. For
239 * every master there are 128 channel id's.
240 */
get_id(u8 * id_array,int max_ids,int base_id,const char * thread_name)241 static struct pti_masterchannel *get_id(u8 *id_array,
242 int max_ids,
243 int base_id,
244 const char *thread_name)
245 {
246 struct pti_masterchannel *mc;
247 int i, j, mask;
248
249 mc = kmalloc(sizeof(struct pti_masterchannel), GFP_KERNEL);
250 if (mc == NULL)
251 return NULL;
252
253 /* look for a byte with a free bit */
254 for (i = 0; i < max_ids; i++)
255 if (id_array[i] != 0xff)
256 break;
257 if (i == max_ids) {
258 kfree(mc);
259 return NULL;
260 }
261 /* find the bit in the 128 possible channel opportunities */
262 mask = 0x80;
263 for (j = 0; j < 8; j++) {
264 if ((id_array[i] & mask) == 0)
265 break;
266 mask >>= 1;
267 }
268
269 /* grab it */
270 id_array[i] |= mask;
271 mc->master = base_id;
272 mc->channel = ((i & 0xf)<<3) + j;
273 /* write new master Id / channel Id allocation to channel control */
274 pti_control_frame_built_and_sent(mc, thread_name);
275 return mc;
276 }
277
278 /*
279 * The following three functions:
280 * pti_request_mastercahannel(), mipi_release_masterchannel()
281 * and pti_writedata() are an API for other kernel drivers to
282 * access PTI.
283 */
284
285 /**
286 * pti_request_masterchannel()- Kernel API function used to allocate
287 * a master, channel ID address
288 * to write to PTI HW.
289 *
290 * @type: 0- request Application master, channel aperture ID
291 * write address.
292 * 1- request OS master, channel aperture ID write
293 * address.
294 * 2- request Modem master, channel aperture ID
295 * write address.
296 * Other values, error.
297 * @thread_name: The thread name associated with the master / channel or
298 * 'NULL' if using the 'current' global variable.
299 *
300 * Returns:
301 * pti_masterchannel struct
302 * 0 for error
303 */
pti_request_masterchannel(u8 type,const char * thread_name)304 struct pti_masterchannel *pti_request_masterchannel(u8 type,
305 const char *thread_name)
306 {
307 struct pti_masterchannel *mc;
308
309 mutex_lock(&alloclock);
310
311 switch (type) {
312
313 case 0:
314 mc = get_id(drv_data->ia_app, MAX_APP_IDS,
315 APP_BASE_ID, thread_name);
316 break;
317
318 case 1:
319 mc = get_id(drv_data->ia_os, MAX_OS_IDS,
320 OS_BASE_ID, thread_name);
321 break;
322
323 case 2:
324 mc = get_id(drv_data->ia_modem, MAX_MODEM_IDS,
325 MODEM_BASE_ID, thread_name);
326 break;
327 default:
328 mc = NULL;
329 }
330
331 mutex_unlock(&alloclock);
332 return mc;
333 }
334 EXPORT_SYMBOL_GPL(pti_request_masterchannel);
335
336 /**
337 * pti_release_masterchannel()- Kernel API function used to release
338 * a master, channel ID address
339 * used to write to PTI HW.
340 *
341 * @mc: master, channel apeture ID address to be released. This
342 * will de-allocate the structure via kfree().
343 */
pti_release_masterchannel(struct pti_masterchannel * mc)344 void pti_release_masterchannel(struct pti_masterchannel *mc)
345 {
346 u8 master, channel, i;
347
348 mutex_lock(&alloclock);
349
350 if (mc) {
351 master = mc->master;
352 channel = mc->channel;
353
354 if (master == APP_BASE_ID) {
355 i = channel >> 3;
356 drv_data->ia_app[i] &= ~(0x80>>(channel & 0x7));
357 } else if (master == OS_BASE_ID) {
358 i = channel >> 3;
359 drv_data->ia_os[i] &= ~(0x80>>(channel & 0x7));
360 } else {
361 i = channel >> 3;
362 drv_data->ia_modem[i] &= ~(0x80>>(channel & 0x7));
363 }
364
365 kfree(mc);
366 }
367
368 mutex_unlock(&alloclock);
369 }
370 EXPORT_SYMBOL_GPL(pti_release_masterchannel);
371
372 /**
373 * pti_writedata()- Kernel API function used to write trace
374 * debugging data to PTI HW.
375 *
376 * @mc: Master, channel aperture ID address to write to.
377 * Null value will return with no write occurring.
378 * @buf: Trace debuging data to write to the PTI HW.
379 * Null value will return with no write occurring.
380 * @count: Size of buf. Value of 0 or a negative number will
381 * return with no write occuring.
382 */
pti_writedata(struct pti_masterchannel * mc,u8 * buf,int count)383 void pti_writedata(struct pti_masterchannel *mc, u8 *buf, int count)
384 {
385 /*
386 * since this function is exported, this is treated like an
387 * API function, thus, all parameters should
388 * be checked for validity.
389 */
390 if ((mc != NULL) && (buf != NULL) && (count > 0))
391 pti_write_to_aperture(mc, buf, count);
392 return;
393 }
394 EXPORT_SYMBOL_GPL(pti_writedata);
395
396 /*
397 * for the tty_driver_*() basic function descriptions, see tty_driver.h.
398 * Specific header comments made for PTI-related specifics.
399 */
400
401 /**
402 * pti_tty_driver_open()- Open an Application master, channel aperture
403 * ID to the PTI device via tty device.
404 *
405 * @tty: tty interface.
406 * @filp: filp interface pased to tty_port_open() call.
407 *
408 * Returns:
409 * int, 0 for success
410 * otherwise, fail value
411 *
412 * The main purpose of using the tty device interface is for
413 * each tty port to have a unique PTI write aperture. In an
414 * example use case, ttyPTI0 gets syslogd and an APP aperture
415 * ID and ttyPTI1 is where the n_tracesink ldisc hooks to route
416 * modem messages into PTI. Modem trace data does not have to
417 * go to ttyPTI1, but ttyPTI0 and ttyPTI1 do need to be distinct
418 * master IDs. These messages go through the PTI HW and out of
419 * the handheld platform and to the Fido/Lauterbach device.
420 */
pti_tty_driver_open(struct tty_struct * tty,struct file * filp)421 static int pti_tty_driver_open(struct tty_struct *tty, struct file *filp)
422 {
423 /*
424 * we actually want to allocate a new channel per open, per
425 * system arch. HW gives more than plenty channels for a single
426 * system task to have its own channel to write trace data. This
427 * also removes a locking requirement for the actual write
428 * procedure.
429 */
430 return tty_port_open(tty->port, tty, filp);
431 }
432
433 /**
434 * pti_tty_driver_close()- close tty device and release Application
435 * master, channel aperture ID to the PTI device via tty device.
436 *
437 * @tty: tty interface.
438 * @filp: filp interface pased to tty_port_close() call.
439 *
440 * The main purpose of using the tty device interface is to route
441 * syslog daemon messages to the PTI HW and out of the handheld platform
442 * and to the Fido/Lauterbach device.
443 */
pti_tty_driver_close(struct tty_struct * tty,struct file * filp)444 static void pti_tty_driver_close(struct tty_struct *tty, struct file *filp)
445 {
446 tty_port_close(tty->port, tty, filp);
447 }
448
449 /**
450 * pti_tty_install()- Used to set up specific master-channels
451 * to tty ports for organizational purposes when
452 * tracing viewed from debuging tools.
453 *
454 * @driver: tty driver information.
455 * @tty: tty struct containing pti information.
456 *
457 * Returns:
458 * 0 for success
459 * otherwise, error
460 */
pti_tty_install(struct tty_driver * driver,struct tty_struct * tty)461 static int pti_tty_install(struct tty_driver *driver, struct tty_struct *tty)
462 {
463 int idx = tty->index;
464 struct pti_tty *pti_tty_data;
465 int ret = tty_standard_install(driver, tty);
466
467 if (ret == 0) {
468 pti_tty_data = kmalloc(sizeof(struct pti_tty), GFP_KERNEL);
469 if (pti_tty_data == NULL)
470 return -ENOMEM;
471
472 if (idx == PTITTY_MINOR_START)
473 pti_tty_data->mc = pti_request_masterchannel(0, NULL);
474 else
475 pti_tty_data->mc = pti_request_masterchannel(2, NULL);
476
477 if (pti_tty_data->mc == NULL) {
478 kfree(pti_tty_data);
479 return -ENXIO;
480 }
481 tty->driver_data = pti_tty_data;
482 }
483
484 return ret;
485 }
486
487 /**
488 * pti_tty_cleanup()- Used to de-allocate master-channel resources
489 * tied to tty's of this driver.
490 *
491 * @tty: tty struct containing pti information.
492 */
pti_tty_cleanup(struct tty_struct * tty)493 static void pti_tty_cleanup(struct tty_struct *tty)
494 {
495 struct pti_tty *pti_tty_data = tty->driver_data;
496 if (pti_tty_data == NULL)
497 return;
498 pti_release_masterchannel(pti_tty_data->mc);
499 kfree(pti_tty_data);
500 tty->driver_data = NULL;
501 }
502
503 /**
504 * pti_tty_driver_write()- Write trace debugging data through the char
505 * interface to the PTI HW. Part of the misc device implementation.
506 *
507 * @filp: Contains private data which is used to obtain
508 * master, channel write ID.
509 * @data: trace data to be written.
510 * @len: # of byte to write.
511 *
512 * Returns:
513 * int, # of bytes written
514 * otherwise, error
515 */
pti_tty_driver_write(struct tty_struct * tty,const unsigned char * buf,int len)516 static int pti_tty_driver_write(struct tty_struct *tty,
517 const unsigned char *buf, int len)
518 {
519 struct pti_tty *pti_tty_data = tty->driver_data;
520 if ((pti_tty_data != NULL) && (pti_tty_data->mc != NULL)) {
521 pti_write_to_aperture(pti_tty_data->mc, (u8 *)buf, len);
522 return len;
523 }
524 /*
525 * we can't write to the pti hardware if the private driver_data
526 * and the mc address is not there.
527 */
528 else
529 return -EFAULT;
530 }
531
532 /**
533 * pti_tty_write_room()- Always returns 2048.
534 *
535 * @tty: contains tty info of the pti driver.
536 */
pti_tty_write_room(struct tty_struct * tty)537 static int pti_tty_write_room(struct tty_struct *tty)
538 {
539 return 2048;
540 }
541
542 /**
543 * pti_char_open()- Open an Application master, channel aperture
544 * ID to the PTI device. Part of the misc device implementation.
545 *
546 * @inode: not used.
547 * @filp: Output- will have a masterchannel struct set containing
548 * the allocated application PTI aperture write address.
549 *
550 * Returns:
551 * int, 0 for success
552 * otherwise, a fail value
553 */
pti_char_open(struct inode * inode,struct file * filp)554 static int pti_char_open(struct inode *inode, struct file *filp)
555 {
556 struct pti_masterchannel *mc;
557
558 /*
559 * We really do want to fail immediately if
560 * pti_request_masterchannel() fails,
561 * before assigning the value to filp->private_data.
562 * Slightly easier to debug if this driver needs debugging.
563 */
564 mc = pti_request_masterchannel(0, NULL);
565 if (mc == NULL)
566 return -ENOMEM;
567 filp->private_data = mc;
568 return 0;
569 }
570
571 /**
572 * pti_char_release()- Close a char channel to the PTI device. Part
573 * of the misc device implementation.
574 *
575 * @inode: Not used in this implementaiton.
576 * @filp: Contains private_data that contains the master, channel
577 * ID to be released by the PTI device.
578 *
579 * Returns:
580 * always 0
581 */
pti_char_release(struct inode * inode,struct file * filp)582 static int pti_char_release(struct inode *inode, struct file *filp)
583 {
584 pti_release_masterchannel(filp->private_data);
585 filp->private_data = NULL;
586 return 0;
587 }
588
589 /**
590 * pti_char_write()- Write trace debugging data through the char
591 * interface to the PTI HW. Part of the misc device implementation.
592 *
593 * @filp: Contains private data which is used to obtain
594 * master, channel write ID.
595 * @data: trace data to be written.
596 * @len: # of byte to write.
597 * @ppose: Not used in this function implementation.
598 *
599 * Returns:
600 * int, # of bytes written
601 * otherwise, error value
602 *
603 * Notes: From side discussions with Alan Cox and experimenting
604 * with PTI debug HW like Nokia's Fido box and Lauterbach
605 * devices, 8192 byte write buffer used by USER_COPY_SIZE was
606 * deemed an appropriate size for this type of usage with
607 * debugging HW.
608 */
pti_char_write(struct file * filp,const char __user * data,size_t len,loff_t * ppose)609 static ssize_t pti_char_write(struct file *filp, const char __user *data,
610 size_t len, loff_t *ppose)
611 {
612 struct pti_masterchannel *mc;
613 void *kbuf;
614 const char __user *tmp;
615 size_t size = USER_COPY_SIZE;
616 size_t n = 0;
617
618 tmp = data;
619 mc = filp->private_data;
620
621 kbuf = kmalloc(size, GFP_KERNEL);
622 if (kbuf == NULL) {
623 pr_err("%s(%d): buf allocation failed\n",
624 __func__, __LINE__);
625 return -ENOMEM;
626 }
627
628 do {
629 if (len - n > USER_COPY_SIZE)
630 size = USER_COPY_SIZE;
631 else
632 size = len - n;
633
634 if (copy_from_user(kbuf, tmp, size)) {
635 kfree(kbuf);
636 return n ? n : -EFAULT;
637 }
638
639 pti_write_to_aperture(mc, kbuf, size);
640 n += size;
641 tmp += size;
642
643 } while (len > n);
644
645 kfree(kbuf);
646 return len;
647 }
648
649 static const struct tty_operations pti_tty_driver_ops = {
650 .open = pti_tty_driver_open,
651 .close = pti_tty_driver_close,
652 .write = pti_tty_driver_write,
653 .write_room = pti_tty_write_room,
654 .install = pti_tty_install,
655 .cleanup = pti_tty_cleanup
656 };
657
658 static const struct file_operations pti_char_driver_ops = {
659 .owner = THIS_MODULE,
660 .write = pti_char_write,
661 .open = pti_char_open,
662 .release = pti_char_release,
663 };
664
665 static struct miscdevice pti_char_driver = {
666 .minor = MISC_DYNAMIC_MINOR,
667 .name = CHARNAME,
668 .fops = &pti_char_driver_ops
669 };
670
671 /**
672 * pti_console_write()- Write to the console that has been acquired.
673 *
674 * @c: Not used in this implementaiton.
675 * @buf: Data to be written.
676 * @len: Length of buf.
677 */
pti_console_write(struct console * c,const char * buf,unsigned len)678 static void pti_console_write(struct console *c, const char *buf, unsigned len)
679 {
680 static struct pti_masterchannel mc = {.master = CONSOLE_ID,
681 .channel = 0};
682
683 mc.channel = pti_console_channel;
684 pti_console_channel = (pti_console_channel + 1) & 0x7f;
685
686 pti_write_full_frame_to_aperture(&mc, buf, len);
687 }
688
689 /**
690 * pti_console_device()- Return the driver tty structure and set the
691 * associated index implementation.
692 *
693 * @c: Console device of the driver.
694 * @index: index associated with c.
695 *
696 * Returns:
697 * always value of pti_tty_driver structure when this function
698 * is called.
699 */
pti_console_device(struct console * c,int * index)700 static struct tty_driver *pti_console_device(struct console *c, int *index)
701 {
702 *index = c->index;
703 return pti_tty_driver;
704 }
705
706 /**
707 * pti_console_setup()- Initialize console variables used by the driver.
708 *
709 * @c: Not used.
710 * @opts: Not used.
711 *
712 * Returns:
713 * always 0.
714 */
pti_console_setup(struct console * c,char * opts)715 static int pti_console_setup(struct console *c, char *opts)
716 {
717 pti_console_channel = 0;
718 pti_control_channel = 0;
719 return 0;
720 }
721
722 /*
723 * pti_console struct, used to capture OS printk()'s and shift
724 * out to the PTI device for debugging. This cannot be
725 * enabled upon boot because of the possibility of eating
726 * any serial console printk's (race condition discovered).
727 * The console should be enabled upon when the tty port is
728 * used for the first time. Since the primary purpose for
729 * the tty port is to hook up syslog to it, the tty port
730 * will be open for a really long time.
731 */
732 static struct console pti_console = {
733 .name = TTYNAME,
734 .write = pti_console_write,
735 .device = pti_console_device,
736 .setup = pti_console_setup,
737 .flags = CON_PRINTBUFFER,
738 .index = 0,
739 };
740
741 /**
742 * pti_port_activate()- Used to start/initialize any items upon
743 * first opening of tty_port().
744 *
745 * @port- The tty port number of the PTI device.
746 * @tty- The tty struct associated with this device.
747 *
748 * Returns:
749 * always returns 0
750 *
751 * Notes: The primary purpose of the PTI tty port 0 is to hook
752 * the syslog daemon to it; thus this port will be open for a
753 * very long time.
754 */
pti_port_activate(struct tty_port * port,struct tty_struct * tty)755 static int pti_port_activate(struct tty_port *port, struct tty_struct *tty)
756 {
757 if (port->tty->index == PTITTY_MINOR_START)
758 console_start(&pti_console);
759 return 0;
760 }
761
762 /**
763 * pti_port_shutdown()- Used to stop/shutdown any items upon the
764 * last tty port close.
765 *
766 * @port- The tty port number of the PTI device.
767 *
768 * Notes: The primary purpose of the PTI tty port 0 is to hook
769 * the syslog daemon to it; thus this port will be open for a
770 * very long time.
771 */
pti_port_shutdown(struct tty_port * port)772 static void pti_port_shutdown(struct tty_port *port)
773 {
774 if (port->tty->index == PTITTY_MINOR_START)
775 console_stop(&pti_console);
776 }
777
778 static const struct tty_port_operations tty_port_ops = {
779 .activate = pti_port_activate,
780 .shutdown = pti_port_shutdown,
781 };
782
783 /*
784 * Note the _probe() call sets everything up and ties the char and tty
785 * to successfully detecting the PTI device on the pci bus.
786 */
787
788 /**
789 * pti_pci_probe()- Used to detect pti on the pci bus and set
790 * things up in the driver.
791 *
792 * @pdev- pci_dev struct values for pti.
793 * @ent- pci_device_id struct for pti driver.
794 *
795 * Returns:
796 * 0 for success
797 * otherwise, error
798 */
pti_pci_probe(struct pci_dev * pdev,const struct pci_device_id * ent)799 static int pti_pci_probe(struct pci_dev *pdev,
800 const struct pci_device_id *ent)
801 {
802 unsigned int a;
803 int retval = -EINVAL;
804 int pci_bar = 1;
805
806 dev_dbg(&pdev->dev, "%s %s(%d): PTI PCI ID %04x:%04x\n", __FILE__,
807 __func__, __LINE__, pdev->vendor, pdev->device);
808
809 retval = misc_register(&pti_char_driver);
810 if (retval) {
811 pr_err("%s(%d): CHAR registration failed of pti driver\n",
812 __func__, __LINE__);
813 pr_err("%s(%d): Error value returned: %d\n",
814 __func__, __LINE__, retval);
815 goto err;
816 }
817
818 retval = pci_enable_device(pdev);
819 if (retval != 0) {
820 dev_err(&pdev->dev,
821 "%s: pci_enable_device() returned error %d\n",
822 __func__, retval);
823 goto err_unreg_misc;
824 }
825
826 drv_data = kzalloc(sizeof(*drv_data), GFP_KERNEL);
827 if (drv_data == NULL) {
828 retval = -ENOMEM;
829 dev_err(&pdev->dev,
830 "%s(%d): kmalloc() returned NULL memory.\n",
831 __func__, __LINE__);
832 goto err_disable_pci;
833 }
834 drv_data->pti_addr = pci_resource_start(pdev, pci_bar);
835
836 retval = pci_request_region(pdev, pci_bar, dev_name(&pdev->dev));
837 if (retval != 0) {
838 dev_err(&pdev->dev,
839 "%s(%d): pci_request_region() returned error %d\n",
840 __func__, __LINE__, retval);
841 goto err_free_dd;
842 }
843 drv_data->aperture_base = drv_data->pti_addr+APERTURE_14;
844 drv_data->pti_ioaddr =
845 ioremap_nocache((u32)drv_data->aperture_base,
846 APERTURE_LEN);
847 if (!drv_data->pti_ioaddr) {
848 retval = -ENOMEM;
849 goto err_rel_reg;
850 }
851
852 pci_set_drvdata(pdev, drv_data);
853
854 for (a = 0; a < PTITTY_MINOR_NUM; a++) {
855 struct tty_port *port = &drv_data->port[a];
856 tty_port_init(port);
857 port->ops = &tty_port_ops;
858
859 tty_port_register_device(port, pti_tty_driver, a, &pdev->dev);
860 }
861
862 register_console(&pti_console);
863
864 return 0;
865 err_rel_reg:
866 pci_release_region(pdev, pci_bar);
867 err_free_dd:
868 kfree(drv_data);
869 err_disable_pci:
870 pci_disable_device(pdev);
871 err_unreg_misc:
872 misc_deregister(&pti_char_driver);
873 err:
874 return retval;
875 }
876
877 /**
878 * pti_pci_remove()- Driver exit method to remove PTI from
879 * PCI bus.
880 * @pdev: variable containing pci info of PTI.
881 */
pti_pci_remove(struct pci_dev * pdev)882 static void pti_pci_remove(struct pci_dev *pdev)
883 {
884 struct pti_dev *drv_data = pci_get_drvdata(pdev);
885 unsigned int a;
886
887 unregister_console(&pti_console);
888
889 for (a = 0; a < PTITTY_MINOR_NUM; a++) {
890 tty_unregister_device(pti_tty_driver, a);
891 tty_port_destroy(&drv_data->port[a]);
892 }
893
894 iounmap(drv_data->pti_ioaddr);
895 kfree(drv_data);
896 pci_release_region(pdev, 1);
897 pci_disable_device(pdev);
898
899 misc_deregister(&pti_char_driver);
900 }
901
902 static struct pci_driver pti_pci_driver = {
903 .name = PCINAME,
904 .id_table = pci_ids,
905 .probe = pti_pci_probe,
906 .remove = pti_pci_remove,
907 };
908
909 /**
910 *
911 * pti_init()- Overall entry/init call to the pti driver.
912 * It starts the registration process with the kernel.
913 *
914 * Returns:
915 * int __init, 0 for success
916 * otherwise value is an error
917 *
918 */
pti_init(void)919 static int __init pti_init(void)
920 {
921 int retval = -EINVAL;
922
923 /* First register module as tty device */
924
925 pti_tty_driver = alloc_tty_driver(PTITTY_MINOR_NUM);
926 if (pti_tty_driver == NULL) {
927 pr_err("%s(%d): Memory allocation failed for ptiTTY driver\n",
928 __func__, __LINE__);
929 return -ENOMEM;
930 }
931
932 pti_tty_driver->driver_name = DRIVERNAME;
933 pti_tty_driver->name = TTYNAME;
934 pti_tty_driver->major = 0;
935 pti_tty_driver->minor_start = PTITTY_MINOR_START;
936 pti_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM;
937 pti_tty_driver->subtype = SYSTEM_TYPE_SYSCONS;
938 pti_tty_driver->flags = TTY_DRIVER_REAL_RAW |
939 TTY_DRIVER_DYNAMIC_DEV;
940 pti_tty_driver->init_termios = tty_std_termios;
941
942 tty_set_operations(pti_tty_driver, &pti_tty_driver_ops);
943
944 retval = tty_register_driver(pti_tty_driver);
945 if (retval) {
946 pr_err("%s(%d): TTY registration failed of pti driver\n",
947 __func__, __LINE__);
948 pr_err("%s(%d): Error value returned: %d\n",
949 __func__, __LINE__, retval);
950
951 goto put_tty;
952 }
953
954 retval = pci_register_driver(&pti_pci_driver);
955 if (retval) {
956 pr_err("%s(%d): PCI registration failed of pti driver\n",
957 __func__, __LINE__);
958 pr_err("%s(%d): Error value returned: %d\n",
959 __func__, __LINE__, retval);
960 goto unreg_tty;
961 }
962
963 return 0;
964 unreg_tty:
965 tty_unregister_driver(pti_tty_driver);
966 put_tty:
967 put_tty_driver(pti_tty_driver);
968 pti_tty_driver = NULL;
969 return retval;
970 }
971
972 /**
973 * pti_exit()- Unregisters this module as a tty and pci driver.
974 */
pti_exit(void)975 static void __exit pti_exit(void)
976 {
977 tty_unregister_driver(pti_tty_driver);
978 pci_unregister_driver(&pti_pci_driver);
979 put_tty_driver(pti_tty_driver);
980 }
981
982 module_init(pti_init);
983 module_exit(pti_exit);
984
985 MODULE_LICENSE("GPL");
986 MODULE_AUTHOR("Ken Mills, Jay Freyensee");
987 MODULE_DESCRIPTION("PTI Driver");
988
989