1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * pti.c - PTI driver for cJTAG data extration
4 *
5 * Copyright (C) Intel 2010
6 *
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8 *
9 * The PTI (Parallel Trace Interface) driver directs trace data routed from
10 * various parts in the system out through the Intel Penwell PTI port and
11 * out of the mobile device for analysis with a debugging tool
12 * (Lauterbach, Fido). This is part of a solution for the MIPI P1149.7,
13 * compact JTAG, standard.
14 */
15
16 #include <linux/init.h>
17 #include <linux/sched.h>
18 #include <linux/interrupt.h>
19 #include <linux/console.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/tty.h>
23 #include <linux/tty_driver.h>
24 #include <linux/pci.h>
25 #include <linux/mutex.h>
26 #include <linux/miscdevice.h>
27 #include <linux/intel-pti.h>
28 #include <linux/slab.h>
29 #include <linux/uaccess.h>
30
31 #define DRIVERNAME "pti"
32 #define PCINAME "pciPTI"
33 #define TTYNAME "ttyPTI"
34 #define CHARNAME "pti"
35 #define PTITTY_MINOR_START 0
36 #define PTITTY_MINOR_NUM 2
37 #define MAX_APP_IDS 16 /* 128 channel ids / u8 bit size */
38 #define MAX_OS_IDS 16 /* 128 channel ids / u8 bit size */
39 #define MAX_MODEM_IDS 16 /* 128 channel ids / u8 bit size */
40 #define MODEM_BASE_ID 71 /* modem master ID address */
41 #define CONTROL_ID 72 /* control master ID address */
42 #define CONSOLE_ID 73 /* console master ID address */
43 #define OS_BASE_ID 74 /* base OS master ID address */
44 #define APP_BASE_ID 80 /* base App master ID address */
45 #define CONTROL_FRAME_LEN 32 /* PTI control frame maximum size */
46 #define USER_COPY_SIZE 8192 /* 8Kb buffer for user space copy */
47 #define APERTURE_14 0x3800000 /* offset to first OS write addr */
48 #define APERTURE_LEN 0x400000 /* address length */
49
50 struct pti_tty {
51 struct pti_masterchannel *mc;
52 };
53
54 struct pti_dev {
55 struct tty_port port[PTITTY_MINOR_NUM];
56 unsigned long pti_addr;
57 unsigned long aperture_base;
58 void __iomem *pti_ioaddr;
59 u8 ia_app[MAX_APP_IDS];
60 u8 ia_os[MAX_OS_IDS];
61 u8 ia_modem[MAX_MODEM_IDS];
62 };
63
64 /*
65 * This protects access to ia_app, ia_os, and ia_modem,
66 * which keeps track of channels allocated in
67 * an aperture write id.
68 */
69 static DEFINE_MUTEX(alloclock);
70
71 static const struct pci_device_id pci_ids[] = {
72 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x82B)},
73 {0}
74 };
75
76 static struct tty_driver *pti_tty_driver;
77 static struct pti_dev *drv_data;
78
79 static unsigned int pti_console_channel;
80 static unsigned int pti_control_channel;
81
82 /**
83 * pti_write_to_aperture()- The private write function to PTI HW.
84 *
85 * @mc: The 'aperture'. It's part of a write address that holds
86 * a master and channel ID.
87 * @buf: Data being written to the HW that will ultimately be seen
88 * in a debugging tool (Fido, Lauterbach).
89 * @len: Size of buffer.
90 *
91 * Since each aperture is specified by a unique
92 * master/channel ID, no two processes will be writing
93 * to the same aperture at the same time so no lock is required. The
94 * PTI-Output agent will send these out in the order that they arrived, and
95 * thus, it will intermix these messages. The debug tool can then later
96 * regroup the appropriate message segments together reconstituting each
97 * message.
98 */
pti_write_to_aperture(struct pti_masterchannel * mc,u8 * buf,int len)99 static void pti_write_to_aperture(struct pti_masterchannel *mc,
100 u8 *buf,
101 int len)
102 {
103 int dwordcnt;
104 int final;
105 int i;
106 u32 ptiword;
107 u32 __iomem *aperture;
108 u8 *p = buf;
109
110 /*
111 * calculate the aperture offset from the base using the master and
112 * channel id's.
113 */
114 aperture = drv_data->pti_ioaddr + (mc->master << 15)
115 + (mc->channel << 8);
116
117 dwordcnt = len >> 2;
118 final = len - (dwordcnt << 2); /* final = trailing bytes */
119 if (final == 0 && dwordcnt != 0) { /* always need a final dword */
120 final += 4;
121 dwordcnt--;
122 }
123
124 for (i = 0; i < dwordcnt; i++) {
125 ptiword = be32_to_cpu(*(u32 *)p);
126 p += 4;
127 iowrite32(ptiword, aperture);
128 }
129
130 aperture += PTI_LASTDWORD_DTS; /* adding DTS signals that is EOM */
131
132 ptiword = 0;
133 for (i = 0; i < final; i++)
134 ptiword |= *p++ << (24-(8*i));
135
136 iowrite32(ptiword, aperture);
137 return;
138 }
139
140 /**
141 * pti_control_frame_built_and_sent()- control frame build and send function.
142 *
143 * @mc: The master / channel structure on which the function
144 * built a control frame.
145 * @thread_name: The thread name associated with the master / channel or
146 * 'NULL' if using the 'current' global variable.
147 *
148 * To be able to post process the PTI contents on host side, a control frame
149 * is added before sending any PTI content. So the host side knows on
150 * each PTI frame the name of the thread using a dedicated master / channel.
151 * The thread name is retrieved from 'current' global variable if 'thread_name'
152 * is 'NULL', else it is retrieved from 'thread_name' parameter.
153 * This function builds this frame and sends it to a master ID CONTROL_ID.
154 * The overhead is only 32 bytes since the driver only writes to HW
155 * in 32 byte chunks.
156 */
pti_control_frame_built_and_sent(struct pti_masterchannel * mc,const char * thread_name)157 static void pti_control_frame_built_and_sent(struct pti_masterchannel *mc,
158 const char *thread_name)
159 {
160 /*
161 * Since we access the comm member in current's task_struct, we only
162 * need to be as large as what 'comm' in that structure is.
163 */
164 char comm[TASK_COMM_LEN];
165 struct pti_masterchannel mccontrol = {.master = CONTROL_ID,
166 .channel = 0};
167 const char *thread_name_p;
168 const char *control_format = "%3d %3d %s";
169 u8 control_frame[CONTROL_FRAME_LEN];
170
171 if (!thread_name) {
172 if (!in_interrupt())
173 get_task_comm(comm, current);
174 else
175 strncpy(comm, "Interrupt", TASK_COMM_LEN);
176
177 /* Absolutely ensure our buffer is zero terminated. */
178 comm[TASK_COMM_LEN-1] = 0;
179 thread_name_p = comm;
180 } else {
181 thread_name_p = thread_name;
182 }
183
184 mccontrol.channel = pti_control_channel;
185 pti_control_channel = (pti_control_channel + 1) & 0x7f;
186
187 snprintf(control_frame, CONTROL_FRAME_LEN, control_format, mc->master,
188 mc->channel, thread_name_p);
189 pti_write_to_aperture(&mccontrol, control_frame, strlen(control_frame));
190 }
191
192 /**
193 * pti_write_full_frame_to_aperture()- high level function to
194 * write to PTI.
195 *
196 * @mc: The 'aperture'. It's part of a write address that holds
197 * a master and channel ID.
198 * @buf: Data being written to the HW that will ultimately be seen
199 * in a debugging tool (Fido, Lauterbach).
200 * @len: Size of buffer.
201 *
202 * All threads sending data (either console, user space application, ...)
203 * are calling the high level function to write to PTI meaning that it is
204 * possible to add a control frame before sending the content.
205 */
pti_write_full_frame_to_aperture(struct pti_masterchannel * mc,const unsigned char * buf,int len)206 static void pti_write_full_frame_to_aperture(struct pti_masterchannel *mc,
207 const unsigned char *buf,
208 int len)
209 {
210 pti_control_frame_built_and_sent(mc, NULL);
211 pti_write_to_aperture(mc, (u8 *)buf, len);
212 }
213
214 /**
215 * get_id()- Allocate a master and channel ID.
216 *
217 * @id_array: an array of bits representing what channel
218 * id's are allocated for writing.
219 * @max_ids: The max amount of available write IDs to use.
220 * @base_id: The starting SW channel ID, based on the Intel
221 * PTI arch.
222 * @thread_name: The thread name associated with the master / channel or
223 * 'NULL' if using the 'current' global variable.
224 *
225 * Returns:
226 * pti_masterchannel struct with master, channel ID address
227 * 0 for error
228 *
229 * Each bit in the arrays ia_app and ia_os correspond to a master and
230 * channel id. The bit is one if the id is taken and 0 if free. For
231 * every master there are 128 channel id's.
232 */
get_id(u8 * id_array,int max_ids,int base_id,const char * thread_name)233 static struct pti_masterchannel *get_id(u8 *id_array,
234 int max_ids,
235 int base_id,
236 const char *thread_name)
237 {
238 struct pti_masterchannel *mc;
239 int i, j, mask;
240
241 mc = kmalloc(sizeof(struct pti_masterchannel), GFP_KERNEL);
242 if (mc == NULL)
243 return NULL;
244
245 /* look for a byte with a free bit */
246 for (i = 0; i < max_ids; i++)
247 if (id_array[i] != 0xff)
248 break;
249 if (i == max_ids) {
250 kfree(mc);
251 return NULL;
252 }
253 /* find the bit in the 128 possible channel opportunities */
254 mask = 0x80;
255 for (j = 0; j < 8; j++) {
256 if ((id_array[i] & mask) == 0)
257 break;
258 mask >>= 1;
259 }
260
261 /* grab it */
262 id_array[i] |= mask;
263 mc->master = base_id;
264 mc->channel = ((i & 0xf)<<3) + j;
265 /* write new master Id / channel Id allocation to channel control */
266 pti_control_frame_built_and_sent(mc, thread_name);
267 return mc;
268 }
269
270 /*
271 * The following three functions:
272 * pti_request_mastercahannel(), mipi_release_masterchannel()
273 * and pti_writedata() are an API for other kernel drivers to
274 * access PTI.
275 */
276
277 /**
278 * pti_request_masterchannel()- Kernel API function used to allocate
279 * a master, channel ID address
280 * to write to PTI HW.
281 *
282 * @type: 0- request Application master, channel aperture ID
283 * write address.
284 * 1- request OS master, channel aperture ID write
285 * address.
286 * 2- request Modem master, channel aperture ID
287 * write address.
288 * Other values, error.
289 * @thread_name: The thread name associated with the master / channel or
290 * 'NULL' if using the 'current' global variable.
291 *
292 * Returns:
293 * pti_masterchannel struct
294 * 0 for error
295 */
pti_request_masterchannel(u8 type,const char * thread_name)296 struct pti_masterchannel *pti_request_masterchannel(u8 type,
297 const char *thread_name)
298 {
299 struct pti_masterchannel *mc;
300
301 mutex_lock(&alloclock);
302
303 switch (type) {
304
305 case 0:
306 mc = get_id(drv_data->ia_app, MAX_APP_IDS,
307 APP_BASE_ID, thread_name);
308 break;
309
310 case 1:
311 mc = get_id(drv_data->ia_os, MAX_OS_IDS,
312 OS_BASE_ID, thread_name);
313 break;
314
315 case 2:
316 mc = get_id(drv_data->ia_modem, MAX_MODEM_IDS,
317 MODEM_BASE_ID, thread_name);
318 break;
319 default:
320 mc = NULL;
321 }
322
323 mutex_unlock(&alloclock);
324 return mc;
325 }
326 EXPORT_SYMBOL_GPL(pti_request_masterchannel);
327
328 /**
329 * pti_release_masterchannel()- Kernel API function used to release
330 * a master, channel ID address
331 * used to write to PTI HW.
332 *
333 * @mc: master, channel apeture ID address to be released. This
334 * will de-allocate the structure via kfree().
335 */
pti_release_masterchannel(struct pti_masterchannel * mc)336 void pti_release_masterchannel(struct pti_masterchannel *mc)
337 {
338 u8 master, channel, i;
339
340 mutex_lock(&alloclock);
341
342 if (mc) {
343 master = mc->master;
344 channel = mc->channel;
345
346 if (master == APP_BASE_ID) {
347 i = channel >> 3;
348 drv_data->ia_app[i] &= ~(0x80>>(channel & 0x7));
349 } else if (master == OS_BASE_ID) {
350 i = channel >> 3;
351 drv_data->ia_os[i] &= ~(0x80>>(channel & 0x7));
352 } else {
353 i = channel >> 3;
354 drv_data->ia_modem[i] &= ~(0x80>>(channel & 0x7));
355 }
356
357 kfree(mc);
358 }
359
360 mutex_unlock(&alloclock);
361 }
362 EXPORT_SYMBOL_GPL(pti_release_masterchannel);
363
364 /**
365 * pti_writedata()- Kernel API function used to write trace
366 * debugging data to PTI HW.
367 *
368 * @mc: Master, channel aperture ID address to write to.
369 * Null value will return with no write occurring.
370 * @buf: Trace debuging data to write to the PTI HW.
371 * Null value will return with no write occurring.
372 * @count: Size of buf. Value of 0 or a negative number will
373 * return with no write occuring.
374 */
pti_writedata(struct pti_masterchannel * mc,u8 * buf,int count)375 void pti_writedata(struct pti_masterchannel *mc, u8 *buf, int count)
376 {
377 /*
378 * since this function is exported, this is treated like an
379 * API function, thus, all parameters should
380 * be checked for validity.
381 */
382 if ((mc != NULL) && (buf != NULL) && (count > 0))
383 pti_write_to_aperture(mc, buf, count);
384 return;
385 }
386 EXPORT_SYMBOL_GPL(pti_writedata);
387
388 /*
389 * for the tty_driver_*() basic function descriptions, see tty_driver.h.
390 * Specific header comments made for PTI-related specifics.
391 */
392
393 /**
394 * pti_tty_driver_open()- Open an Application master, channel aperture
395 * ID to the PTI device via tty device.
396 *
397 * @tty: tty interface.
398 * @filp: filp interface pased to tty_port_open() call.
399 *
400 * Returns:
401 * int, 0 for success
402 * otherwise, fail value
403 *
404 * The main purpose of using the tty device interface is for
405 * each tty port to have a unique PTI write aperture. In an
406 * example use case, ttyPTI0 gets syslogd and an APP aperture
407 * ID and ttyPTI1 is where the n_tracesink ldisc hooks to route
408 * modem messages into PTI. Modem trace data does not have to
409 * go to ttyPTI1, but ttyPTI0 and ttyPTI1 do need to be distinct
410 * master IDs. These messages go through the PTI HW and out of
411 * the handheld platform and to the Fido/Lauterbach device.
412 */
pti_tty_driver_open(struct tty_struct * tty,struct file * filp)413 static int pti_tty_driver_open(struct tty_struct *tty, struct file *filp)
414 {
415 /*
416 * we actually want to allocate a new channel per open, per
417 * system arch. HW gives more than plenty channels for a single
418 * system task to have its own channel to write trace data. This
419 * also removes a locking requirement for the actual write
420 * procedure.
421 */
422 return tty_port_open(tty->port, tty, filp);
423 }
424
425 /**
426 * pti_tty_driver_close()- close tty device and release Application
427 * master, channel aperture ID to the PTI device via tty device.
428 *
429 * @tty: tty interface.
430 * @filp: filp interface pased to tty_port_close() call.
431 *
432 * The main purpose of using the tty device interface is to route
433 * syslog daemon messages to the PTI HW and out of the handheld platform
434 * and to the Fido/Lauterbach device.
435 */
pti_tty_driver_close(struct tty_struct * tty,struct file * filp)436 static void pti_tty_driver_close(struct tty_struct *tty, struct file *filp)
437 {
438 tty_port_close(tty->port, tty, filp);
439 }
440
441 /**
442 * pti_tty_install()- Used to set up specific master-channels
443 * to tty ports for organizational purposes when
444 * tracing viewed from debuging tools.
445 *
446 * @driver: tty driver information.
447 * @tty: tty struct containing pti information.
448 *
449 * Returns:
450 * 0 for success
451 * otherwise, error
452 */
pti_tty_install(struct tty_driver * driver,struct tty_struct * tty)453 static int pti_tty_install(struct tty_driver *driver, struct tty_struct *tty)
454 {
455 int idx = tty->index;
456 struct pti_tty *pti_tty_data;
457 int ret = tty_standard_install(driver, tty);
458
459 if (ret == 0) {
460 pti_tty_data = kmalloc(sizeof(struct pti_tty), GFP_KERNEL);
461 if (pti_tty_data == NULL)
462 return -ENOMEM;
463
464 if (idx == PTITTY_MINOR_START)
465 pti_tty_data->mc = pti_request_masterchannel(0, NULL);
466 else
467 pti_tty_data->mc = pti_request_masterchannel(2, NULL);
468
469 if (pti_tty_data->mc == NULL) {
470 kfree(pti_tty_data);
471 return -ENXIO;
472 }
473 tty->driver_data = pti_tty_data;
474 }
475
476 return ret;
477 }
478
479 /**
480 * pti_tty_cleanup()- Used to de-allocate master-channel resources
481 * tied to tty's of this driver.
482 *
483 * @tty: tty struct containing pti information.
484 */
pti_tty_cleanup(struct tty_struct * tty)485 static void pti_tty_cleanup(struct tty_struct *tty)
486 {
487 struct pti_tty *pti_tty_data = tty->driver_data;
488 if (pti_tty_data == NULL)
489 return;
490 pti_release_masterchannel(pti_tty_data->mc);
491 kfree(pti_tty_data);
492 tty->driver_data = NULL;
493 }
494
495 /**
496 * pti_tty_driver_write()- Write trace debugging data through the char
497 * interface to the PTI HW. Part of the misc device implementation.
498 *
499 * @tty: tty struct containing pti information.
500 * @buf: trace data to be written.
501 * @len: # of byte to write.
502 *
503 * Returns:
504 * int, # of bytes written
505 * otherwise, error
506 */
pti_tty_driver_write(struct tty_struct * tty,const unsigned char * buf,int len)507 static int pti_tty_driver_write(struct tty_struct *tty,
508 const unsigned char *buf, int len)
509 {
510 struct pti_tty *pti_tty_data = tty->driver_data;
511 if ((pti_tty_data != NULL) && (pti_tty_data->mc != NULL)) {
512 pti_write_to_aperture(pti_tty_data->mc, (u8 *)buf, len);
513 return len;
514 }
515 /*
516 * we can't write to the pti hardware if the private driver_data
517 * and the mc address is not there.
518 */
519 else
520 return -EFAULT;
521 }
522
523 /**
524 * pti_tty_write_room()- Always returns 2048.
525 *
526 * @tty: contains tty info of the pti driver.
527 */
pti_tty_write_room(struct tty_struct * tty)528 static int pti_tty_write_room(struct tty_struct *tty)
529 {
530 return 2048;
531 }
532
533 /**
534 * pti_char_open()- Open an Application master, channel aperture
535 * ID to the PTI device. Part of the misc device implementation.
536 *
537 * @inode: not used.
538 * @filp: Output- will have a masterchannel struct set containing
539 * the allocated application PTI aperture write address.
540 *
541 * Returns:
542 * int, 0 for success
543 * otherwise, a fail value
544 */
pti_char_open(struct inode * inode,struct file * filp)545 static int pti_char_open(struct inode *inode, struct file *filp)
546 {
547 struct pti_masterchannel *mc;
548
549 /*
550 * We really do want to fail immediately if
551 * pti_request_masterchannel() fails,
552 * before assigning the value to filp->private_data.
553 * Slightly easier to debug if this driver needs debugging.
554 */
555 mc = pti_request_masterchannel(0, NULL);
556 if (mc == NULL)
557 return -ENOMEM;
558 filp->private_data = mc;
559 return 0;
560 }
561
562 /**
563 * pti_char_release()- Close a char channel to the PTI device. Part
564 * of the misc device implementation.
565 *
566 * @inode: Not used in this implementaiton.
567 * @filp: Contains private_data that contains the master, channel
568 * ID to be released by the PTI device.
569 *
570 * Returns:
571 * always 0
572 */
pti_char_release(struct inode * inode,struct file * filp)573 static int pti_char_release(struct inode *inode, struct file *filp)
574 {
575 pti_release_masterchannel(filp->private_data);
576 filp->private_data = NULL;
577 return 0;
578 }
579
580 /**
581 * pti_char_write()- Write trace debugging data through the char
582 * interface to the PTI HW. Part of the misc device implementation.
583 *
584 * @filp: Contains private data which is used to obtain
585 * master, channel write ID.
586 * @data: trace data to be written.
587 * @len: # of byte to write.
588 * @ppose: Not used in this function implementation.
589 *
590 * Returns:
591 * int, # of bytes written
592 * otherwise, error value
593 *
594 * Notes: From side discussions with Alan Cox and experimenting
595 * with PTI debug HW like Nokia's Fido box and Lauterbach
596 * devices, 8192 byte write buffer used by USER_COPY_SIZE was
597 * deemed an appropriate size for this type of usage with
598 * debugging HW.
599 */
pti_char_write(struct file * filp,const char __user * data,size_t len,loff_t * ppose)600 static ssize_t pti_char_write(struct file *filp, const char __user *data,
601 size_t len, loff_t *ppose)
602 {
603 struct pti_masterchannel *mc;
604 void *kbuf;
605 const char __user *tmp;
606 size_t size = USER_COPY_SIZE;
607 size_t n = 0;
608
609 tmp = data;
610 mc = filp->private_data;
611
612 kbuf = kmalloc(size, GFP_KERNEL);
613 if (kbuf == NULL) {
614 pr_err("%s(%d): buf allocation failed\n",
615 __func__, __LINE__);
616 return -ENOMEM;
617 }
618
619 do {
620 if (len - n > USER_COPY_SIZE)
621 size = USER_COPY_SIZE;
622 else
623 size = len - n;
624
625 if (copy_from_user(kbuf, tmp, size)) {
626 kfree(kbuf);
627 return n ? n : -EFAULT;
628 }
629
630 pti_write_to_aperture(mc, kbuf, size);
631 n += size;
632 tmp += size;
633
634 } while (len > n);
635
636 kfree(kbuf);
637 return len;
638 }
639
640 static const struct tty_operations pti_tty_driver_ops = {
641 .open = pti_tty_driver_open,
642 .close = pti_tty_driver_close,
643 .write = pti_tty_driver_write,
644 .write_room = pti_tty_write_room,
645 .install = pti_tty_install,
646 .cleanup = pti_tty_cleanup
647 };
648
649 static const struct file_operations pti_char_driver_ops = {
650 .owner = THIS_MODULE,
651 .write = pti_char_write,
652 .open = pti_char_open,
653 .release = pti_char_release,
654 };
655
656 static struct miscdevice pti_char_driver = {
657 .minor = MISC_DYNAMIC_MINOR,
658 .name = CHARNAME,
659 .fops = &pti_char_driver_ops
660 };
661
662 /**
663 * pti_console_write()- Write to the console that has been acquired.
664 *
665 * @c: Not used in this implementaiton.
666 * @buf: Data to be written.
667 * @len: Length of buf.
668 */
pti_console_write(struct console * c,const char * buf,unsigned len)669 static void pti_console_write(struct console *c, const char *buf, unsigned len)
670 {
671 static struct pti_masterchannel mc = {.master = CONSOLE_ID,
672 .channel = 0};
673
674 mc.channel = pti_console_channel;
675 pti_console_channel = (pti_console_channel + 1) & 0x7f;
676
677 pti_write_full_frame_to_aperture(&mc, buf, len);
678 }
679
680 /**
681 * pti_console_device()- Return the driver tty structure and set the
682 * associated index implementation.
683 *
684 * @c: Console device of the driver.
685 * @index: index associated with c.
686 *
687 * Returns:
688 * always value of pti_tty_driver structure when this function
689 * is called.
690 */
pti_console_device(struct console * c,int * index)691 static struct tty_driver *pti_console_device(struct console *c, int *index)
692 {
693 *index = c->index;
694 return pti_tty_driver;
695 }
696
697 /**
698 * pti_console_setup()- Initialize console variables used by the driver.
699 *
700 * @c: Not used.
701 * @opts: Not used.
702 *
703 * Returns:
704 * always 0.
705 */
pti_console_setup(struct console * c,char * opts)706 static int pti_console_setup(struct console *c, char *opts)
707 {
708 pti_console_channel = 0;
709 pti_control_channel = 0;
710 return 0;
711 }
712
713 /*
714 * pti_console struct, used to capture OS printk()'s and shift
715 * out to the PTI device for debugging. This cannot be
716 * enabled upon boot because of the possibility of eating
717 * any serial console printk's (race condition discovered).
718 * The console should be enabled upon when the tty port is
719 * used for the first time. Since the primary purpose for
720 * the tty port is to hook up syslog to it, the tty port
721 * will be open for a really long time.
722 */
723 static struct console pti_console = {
724 .name = TTYNAME,
725 .write = pti_console_write,
726 .device = pti_console_device,
727 .setup = pti_console_setup,
728 .flags = CON_PRINTBUFFER,
729 .index = 0,
730 };
731
732 /**
733 * pti_port_activate()- Used to start/initialize any items upon
734 * first opening of tty_port().
735 *
736 * @port: The tty port number of the PTI device.
737 * @tty: The tty struct associated with this device.
738 *
739 * Returns:
740 * always returns 0
741 *
742 * Notes: The primary purpose of the PTI tty port 0 is to hook
743 * the syslog daemon to it; thus this port will be open for a
744 * very long time.
745 */
pti_port_activate(struct tty_port * port,struct tty_struct * tty)746 static int pti_port_activate(struct tty_port *port, struct tty_struct *tty)
747 {
748 if (port->tty->index == PTITTY_MINOR_START)
749 console_start(&pti_console);
750 return 0;
751 }
752
753 /**
754 * pti_port_shutdown()- Used to stop/shutdown any items upon the
755 * last tty port close.
756 *
757 * @port: The tty port number of the PTI device.
758 *
759 * Notes: The primary purpose of the PTI tty port 0 is to hook
760 * the syslog daemon to it; thus this port will be open for a
761 * very long time.
762 */
pti_port_shutdown(struct tty_port * port)763 static void pti_port_shutdown(struct tty_port *port)
764 {
765 if (port->tty->index == PTITTY_MINOR_START)
766 console_stop(&pti_console);
767 }
768
769 static const struct tty_port_operations tty_port_ops = {
770 .activate = pti_port_activate,
771 .shutdown = pti_port_shutdown,
772 };
773
774 /*
775 * Note the _probe() call sets everything up and ties the char and tty
776 * to successfully detecting the PTI device on the pci bus.
777 */
778
779 /**
780 * pti_pci_probe()- Used to detect pti on the pci bus and set
781 * things up in the driver.
782 *
783 * @pdev: pci_dev struct values for pti.
784 * @ent: pci_device_id struct for pti driver.
785 *
786 * Returns:
787 * 0 for success
788 * otherwise, error
789 */
pti_pci_probe(struct pci_dev * pdev,const struct pci_device_id * ent)790 static int pti_pci_probe(struct pci_dev *pdev,
791 const struct pci_device_id *ent)
792 {
793 unsigned int a;
794 int retval;
795 int pci_bar = 1;
796
797 dev_dbg(&pdev->dev, "%s %s(%d): PTI PCI ID %04x:%04x\n", __FILE__,
798 __func__, __LINE__, pdev->vendor, pdev->device);
799
800 retval = misc_register(&pti_char_driver);
801 if (retval) {
802 pr_err("%s(%d): CHAR registration failed of pti driver\n",
803 __func__, __LINE__);
804 pr_err("%s(%d): Error value returned: %d\n",
805 __func__, __LINE__, retval);
806 goto err;
807 }
808
809 retval = pci_enable_device(pdev);
810 if (retval != 0) {
811 dev_err(&pdev->dev,
812 "%s: pci_enable_device() returned error %d\n",
813 __func__, retval);
814 goto err_unreg_misc;
815 }
816
817 drv_data = kzalloc(sizeof(*drv_data), GFP_KERNEL);
818 if (drv_data == NULL) {
819 retval = -ENOMEM;
820 dev_err(&pdev->dev,
821 "%s(%d): kmalloc() returned NULL memory.\n",
822 __func__, __LINE__);
823 goto err_disable_pci;
824 }
825 drv_data->pti_addr = pci_resource_start(pdev, pci_bar);
826
827 retval = pci_request_region(pdev, pci_bar, dev_name(&pdev->dev));
828 if (retval != 0) {
829 dev_err(&pdev->dev,
830 "%s(%d): pci_request_region() returned error %d\n",
831 __func__, __LINE__, retval);
832 goto err_free_dd;
833 }
834 drv_data->aperture_base = drv_data->pti_addr+APERTURE_14;
835 drv_data->pti_ioaddr =
836 ioremap((u32)drv_data->aperture_base,
837 APERTURE_LEN);
838 if (!drv_data->pti_ioaddr) {
839 retval = -ENOMEM;
840 goto err_rel_reg;
841 }
842
843 pci_set_drvdata(pdev, drv_data);
844
845 for (a = 0; a < PTITTY_MINOR_NUM; a++) {
846 struct tty_port *port = &drv_data->port[a];
847 tty_port_init(port);
848 port->ops = &tty_port_ops;
849
850 tty_port_register_device(port, pti_tty_driver, a, &pdev->dev);
851 }
852
853 register_console(&pti_console);
854
855 return 0;
856 err_rel_reg:
857 pci_release_region(pdev, pci_bar);
858 err_free_dd:
859 kfree(drv_data);
860 err_disable_pci:
861 pci_disable_device(pdev);
862 err_unreg_misc:
863 misc_deregister(&pti_char_driver);
864 err:
865 return retval;
866 }
867
868 /**
869 * pti_pci_remove()- Driver exit method to remove PTI from
870 * PCI bus.
871 * @pdev: variable containing pci info of PTI.
872 */
pti_pci_remove(struct pci_dev * pdev)873 static void pti_pci_remove(struct pci_dev *pdev)
874 {
875 struct pti_dev *drv_data = pci_get_drvdata(pdev);
876 unsigned int a;
877
878 unregister_console(&pti_console);
879
880 for (a = 0; a < PTITTY_MINOR_NUM; a++) {
881 tty_unregister_device(pti_tty_driver, a);
882 tty_port_destroy(&drv_data->port[a]);
883 }
884
885 iounmap(drv_data->pti_ioaddr);
886 kfree(drv_data);
887 pci_release_region(pdev, 1);
888 pci_disable_device(pdev);
889
890 misc_deregister(&pti_char_driver);
891 }
892
893 static struct pci_driver pti_pci_driver = {
894 .name = PCINAME,
895 .id_table = pci_ids,
896 .probe = pti_pci_probe,
897 .remove = pti_pci_remove,
898 };
899
900 /**
901 * pti_init()- Overall entry/init call to the pti driver.
902 * It starts the registration process with the kernel.
903 *
904 * Returns:
905 * int __init, 0 for success
906 * otherwise value is an error
907 *
908 */
pti_init(void)909 static int __init pti_init(void)
910 {
911 int retval;
912
913 /* First register module as tty device */
914
915 pti_tty_driver = alloc_tty_driver(PTITTY_MINOR_NUM);
916 if (pti_tty_driver == NULL) {
917 pr_err("%s(%d): Memory allocation failed for ptiTTY driver\n",
918 __func__, __LINE__);
919 return -ENOMEM;
920 }
921
922 pti_tty_driver->driver_name = DRIVERNAME;
923 pti_tty_driver->name = TTYNAME;
924 pti_tty_driver->major = 0;
925 pti_tty_driver->minor_start = PTITTY_MINOR_START;
926 pti_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM;
927 pti_tty_driver->subtype = SYSTEM_TYPE_SYSCONS;
928 pti_tty_driver->flags = TTY_DRIVER_REAL_RAW |
929 TTY_DRIVER_DYNAMIC_DEV;
930 pti_tty_driver->init_termios = tty_std_termios;
931
932 tty_set_operations(pti_tty_driver, &pti_tty_driver_ops);
933
934 retval = tty_register_driver(pti_tty_driver);
935 if (retval) {
936 pr_err("%s(%d): TTY registration failed of pti driver\n",
937 __func__, __LINE__);
938 pr_err("%s(%d): Error value returned: %d\n",
939 __func__, __LINE__, retval);
940
941 goto put_tty;
942 }
943
944 retval = pci_register_driver(&pti_pci_driver);
945 if (retval) {
946 pr_err("%s(%d): PCI registration failed of pti driver\n",
947 __func__, __LINE__);
948 pr_err("%s(%d): Error value returned: %d\n",
949 __func__, __LINE__, retval);
950 goto unreg_tty;
951 }
952
953 return 0;
954 unreg_tty:
955 tty_unregister_driver(pti_tty_driver);
956 put_tty:
957 put_tty_driver(pti_tty_driver);
958 pti_tty_driver = NULL;
959 return retval;
960 }
961
962 /**
963 * pti_exit()- Unregisters this module as a tty and pci driver.
964 */
pti_exit(void)965 static void __exit pti_exit(void)
966 {
967 tty_unregister_driver(pti_tty_driver);
968 pci_unregister_driver(&pti_pci_driver);
969 put_tty_driver(pti_tty_driver);
970 }
971
972 module_init(pti_init);
973 module_exit(pti_exit);
974
975 MODULE_LICENSE("GPL");
976 MODULE_AUTHOR("Ken Mills, Jay Freyensee");
977 MODULE_DESCRIPTION("PTI Driver");
978
979
