1 /*
2 * vio driver interface to hvc_console.c
3 *
4 * This code was moved here to allow the remaining code to be reused as a
5 * generic polling mode with semi-reliable transport driver core to the
6 * console and tty subsystems.
7 *
8 *
9 * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
10 * Copyright (C) 2001 Paul Mackerras <paulus@au.ibm.com>, IBM
11 * Copyright (C) 2004 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
12 * Copyright (C) 2004 IBM Corporation
13 *
14 * Additional Author(s):
15 * Ryan S. Arnold <rsa@us.ibm.com>
16 *
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License as published by
19 * the Free Software Foundation; either version 2 of the License, or
20 * (at your option) any later version.
21 *
22 * This program is distributed in the hope that it will be useful,
23 * but WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
25 * GNU General Public License for more details.
26 *
27 * You should have received a copy of the GNU General Public License
28 * along with this program; if not, write to the Free Software
29 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
30 *
31 * TODO:
32 *
33 * - handle error in sending hvsi protocol packets
34 * - retry nego on subsequent sends ?
35 */
36
37 #undef DEBUG
38
39 #include <linux/types.h>
40 #include <linux/init.h>
41 #include <linux/delay.h>
42 #include <linux/slab.h>
43 #include <linux/console.h>
44 #include <linux/module.h>
45
46 #include <asm/hvconsole.h>
47 #include <asm/vio.h>
48 #include <asm/prom.h>
49 #include <asm/hvsi.h>
50 #include <asm/udbg.h>
51 #include <asm/machdep.h>
52
53 #include "hvc_console.h"
54
55 static const char hvc_driver_name[] = "hvc_console";
56
57 static struct vio_device_id hvc_driver_table[] = {
58 {"serial", "hvterm1"},
59 #ifndef HVC_OLD_HVSI
60 {"serial", "hvterm-protocol"},
61 #endif
62 { "", "" }
63 };
64 MODULE_DEVICE_TABLE(vio, hvc_driver_table);
65
66 typedef enum hv_protocol {
67 HV_PROTOCOL_RAW,
68 HV_PROTOCOL_HVSI
69 } hv_protocol_t;
70
71 struct hvterm_priv {
72 u32 termno; /* HV term number */
73 hv_protocol_t proto; /* Raw data or HVSI packets */
74 struct hvsi_priv hvsi; /* HVSI specific data */
75 spinlock_t buf_lock;
76 char buf[SIZE_VIO_GET_CHARS];
77 int left;
78 int offset;
79 };
80 static struct hvterm_priv *hvterm_privs[MAX_NR_HVC_CONSOLES];
81 /* For early boot console */
82 static struct hvterm_priv hvterm_priv0;
83
hvterm_raw_get_chars(uint32_t vtermno,char * buf,int count)84 static int hvterm_raw_get_chars(uint32_t vtermno, char *buf, int count)
85 {
86 struct hvterm_priv *pv = hvterm_privs[vtermno];
87 unsigned long i;
88 unsigned long flags;
89 int got;
90
91 if (WARN_ON(!pv))
92 return 0;
93
94 spin_lock_irqsave(&pv->buf_lock, flags);
95
96 if (pv->left == 0) {
97 pv->offset = 0;
98 pv->left = hvc_get_chars(pv->termno, pv->buf, count);
99
100 /*
101 * Work around a HV bug where it gives us a null
102 * after every \r. -- paulus
103 */
104 for (i = 1; i < pv->left; ++i) {
105 if (pv->buf[i] == 0 && pv->buf[i-1] == '\r') {
106 --pv->left;
107 if (i < pv->left) {
108 memmove(&pv->buf[i], &pv->buf[i+1],
109 pv->left - i);
110 }
111 }
112 }
113 }
114
115 got = min(count, pv->left);
116 memcpy(buf, &pv->buf[pv->offset], got);
117 pv->offset += got;
118 pv->left -= got;
119
120 spin_unlock_irqrestore(&pv->buf_lock, flags);
121
122 return got;
123 }
124
125 /**
126 * hvterm_raw_put_chars: send characters to firmware for given vterm adapter
127 * @vtermno: The virtual terminal number.
128 * @buf: The characters to send. Because of the underlying hypercall in
129 * hvc_put_chars(), this buffer must be at least 16 bytes long, even if
130 * you are sending fewer chars.
131 * @count: number of chars to send.
132 */
hvterm_raw_put_chars(uint32_t vtermno,const char * buf,int count)133 static int hvterm_raw_put_chars(uint32_t vtermno, const char *buf, int count)
134 {
135 struct hvterm_priv *pv = hvterm_privs[vtermno];
136
137 if (WARN_ON(!pv))
138 return 0;
139
140 return hvc_put_chars(pv->termno, buf, count);
141 }
142
143 static const struct hv_ops hvterm_raw_ops = {
144 .get_chars = hvterm_raw_get_chars,
145 .put_chars = hvterm_raw_put_chars,
146 .notifier_add = notifier_add_irq,
147 .notifier_del = notifier_del_irq,
148 .notifier_hangup = notifier_hangup_irq,
149 };
150
hvterm_hvsi_get_chars(uint32_t vtermno,char * buf,int count)151 static int hvterm_hvsi_get_chars(uint32_t vtermno, char *buf, int count)
152 {
153 struct hvterm_priv *pv = hvterm_privs[vtermno];
154
155 if (WARN_ON(!pv))
156 return 0;
157
158 return hvsilib_get_chars(&pv->hvsi, buf, count);
159 }
160
hvterm_hvsi_put_chars(uint32_t vtermno,const char * buf,int count)161 static int hvterm_hvsi_put_chars(uint32_t vtermno, const char *buf, int count)
162 {
163 struct hvterm_priv *pv = hvterm_privs[vtermno];
164
165 if (WARN_ON(!pv))
166 return 0;
167
168 return hvsilib_put_chars(&pv->hvsi, buf, count);
169 }
170
hvterm_hvsi_open(struct hvc_struct * hp,int data)171 static int hvterm_hvsi_open(struct hvc_struct *hp, int data)
172 {
173 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
174 int rc;
175
176 pr_devel("HVSI@%x: open !\n", pv->termno);
177
178 rc = notifier_add_irq(hp, data);
179 if (rc)
180 return rc;
181
182 return hvsilib_open(&pv->hvsi, hp);
183 }
184
hvterm_hvsi_close(struct hvc_struct * hp,int data)185 static void hvterm_hvsi_close(struct hvc_struct *hp, int data)
186 {
187 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
188
189 pr_devel("HVSI@%x: do close !\n", pv->termno);
190
191 hvsilib_close(&pv->hvsi, hp);
192
193 notifier_del_irq(hp, data);
194 }
195
hvterm_hvsi_hangup(struct hvc_struct * hp,int data)196 void hvterm_hvsi_hangup(struct hvc_struct *hp, int data)
197 {
198 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
199
200 pr_devel("HVSI@%x: do hangup !\n", pv->termno);
201
202 hvsilib_close(&pv->hvsi, hp);
203
204 notifier_hangup_irq(hp, data);
205 }
206
hvterm_hvsi_tiocmget(struct hvc_struct * hp)207 static int hvterm_hvsi_tiocmget(struct hvc_struct *hp)
208 {
209 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
210
211 if (!pv)
212 return -EINVAL;
213 return pv->hvsi.mctrl;
214 }
215
hvterm_hvsi_tiocmset(struct hvc_struct * hp,unsigned int set,unsigned int clear)216 static int hvterm_hvsi_tiocmset(struct hvc_struct *hp, unsigned int set,
217 unsigned int clear)
218 {
219 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
220
221 pr_devel("HVSI@%x: Set modem control, set=%x,clr=%x\n",
222 pv->termno, set, clear);
223
224 if (set & TIOCM_DTR)
225 hvsilib_write_mctrl(&pv->hvsi, 1);
226 else if (clear & TIOCM_DTR)
227 hvsilib_write_mctrl(&pv->hvsi, 0);
228
229 return 0;
230 }
231
232 static const struct hv_ops hvterm_hvsi_ops = {
233 .get_chars = hvterm_hvsi_get_chars,
234 .put_chars = hvterm_hvsi_put_chars,
235 .notifier_add = hvterm_hvsi_open,
236 .notifier_del = hvterm_hvsi_close,
237 .notifier_hangup = hvterm_hvsi_hangup,
238 .tiocmget = hvterm_hvsi_tiocmget,
239 .tiocmset = hvterm_hvsi_tiocmset,
240 };
241
udbg_hvc_putc(char c)242 static void udbg_hvc_putc(char c)
243 {
244 int count = -1;
245 unsigned char bounce_buffer[16];
246
247 if (!hvterm_privs[0])
248 return;
249
250 if (c == '\n')
251 udbg_hvc_putc('\r');
252
253 do {
254 switch(hvterm_privs[0]->proto) {
255 case HV_PROTOCOL_RAW:
256 /*
257 * hvterm_raw_put_chars requires at least a 16-byte
258 * buffer, so go via the bounce buffer
259 */
260 bounce_buffer[0] = c;
261 count = hvterm_raw_put_chars(0, bounce_buffer, 1);
262 break;
263 case HV_PROTOCOL_HVSI:
264 count = hvterm_hvsi_put_chars(0, &c, 1);
265 break;
266 }
267 } while(count == 0);
268 }
269
udbg_hvc_getc_poll(void)270 static int udbg_hvc_getc_poll(void)
271 {
272 int rc = 0;
273 char c;
274
275 if (!hvterm_privs[0])
276 return -1;
277
278 switch(hvterm_privs[0]->proto) {
279 case HV_PROTOCOL_RAW:
280 rc = hvterm_raw_get_chars(0, &c, 1);
281 break;
282 case HV_PROTOCOL_HVSI:
283 rc = hvterm_hvsi_get_chars(0, &c, 1);
284 break;
285 }
286 if (!rc)
287 return -1;
288 return c;
289 }
290
udbg_hvc_getc(void)291 static int udbg_hvc_getc(void)
292 {
293 int ch;
294
295 if (!hvterm_privs[0])
296 return -1;
297
298 for (;;) {
299 ch = udbg_hvc_getc_poll();
300 if (ch == -1) {
301 /* This shouldn't be needed...but... */
302 volatile unsigned long delay;
303 for (delay=0; delay < 2000000; delay++)
304 ;
305 } else {
306 return ch;
307 }
308 }
309 }
310
hvc_vio_probe(struct vio_dev * vdev,const struct vio_device_id * id)311 static int hvc_vio_probe(struct vio_dev *vdev,
312 const struct vio_device_id *id)
313 {
314 const struct hv_ops *ops;
315 struct hvc_struct *hp;
316 struct hvterm_priv *pv;
317 hv_protocol_t proto;
318 int i, termno = -1;
319
320 /* probed with invalid parameters. */
321 if (!vdev || !id)
322 return -EPERM;
323
324 if (of_device_is_compatible(vdev->dev.of_node, "hvterm1")) {
325 proto = HV_PROTOCOL_RAW;
326 ops = &hvterm_raw_ops;
327 } else if (of_device_is_compatible(vdev->dev.of_node, "hvterm-protocol")) {
328 proto = HV_PROTOCOL_HVSI;
329 ops = &hvterm_hvsi_ops;
330 } else {
331 pr_err("hvc_vio: Unknown protocol for %s\n", vdev->dev.of_node->full_name);
332 return -ENXIO;
333 }
334
335 pr_devel("hvc_vio_probe() device %s, using %s protocol\n",
336 vdev->dev.of_node->full_name,
337 proto == HV_PROTOCOL_RAW ? "raw" : "hvsi");
338
339 /* Is it our boot one ? */
340 if (hvterm_privs[0] == &hvterm_priv0 &&
341 vdev->unit_address == hvterm_priv0.termno) {
342 pv = hvterm_privs[0];
343 termno = 0;
344 pr_devel("->boot console, using termno 0\n");
345 }
346 /* nope, allocate a new one */
347 else {
348 for (i = 0; i < MAX_NR_HVC_CONSOLES && termno < 0; i++)
349 if (!hvterm_privs[i])
350 termno = i;
351 pr_devel("->non-boot console, using termno %d\n", termno);
352 if (termno < 0)
353 return -ENODEV;
354 pv = kzalloc(sizeof(struct hvterm_priv), GFP_KERNEL);
355 if (!pv)
356 return -ENOMEM;
357 pv->termno = vdev->unit_address;
358 pv->proto = proto;
359 spin_lock_init(&pv->buf_lock);
360 hvterm_privs[termno] = pv;
361 hvsilib_init(&pv->hvsi, hvc_get_chars, hvc_put_chars,
362 pv->termno, 0);
363 }
364
365 hp = hvc_alloc(termno, vdev->irq, ops, MAX_VIO_PUT_CHARS);
366 if (IS_ERR(hp))
367 return PTR_ERR(hp);
368 dev_set_drvdata(&vdev->dev, hp);
369
370 /* register udbg if it's not there already for console 0 */
371 if (hp->index == 0 && !udbg_putc) {
372 udbg_putc = udbg_hvc_putc;
373 udbg_getc = udbg_hvc_getc;
374 udbg_getc_poll = udbg_hvc_getc_poll;
375 }
376
377 return 0;
378 }
379
hvc_vio_remove(struct vio_dev * vdev)380 static int hvc_vio_remove(struct vio_dev *vdev)
381 {
382 struct hvc_struct *hp = dev_get_drvdata(&vdev->dev);
383 int rc, termno;
384
385 termno = hp->vtermno;
386 rc = hvc_remove(hp);
387 if (rc == 0) {
388 if (hvterm_privs[termno] != &hvterm_priv0)
389 kfree(hvterm_privs[termno]);
390 hvterm_privs[termno] = NULL;
391 }
392 return rc;
393 }
394
395 static struct vio_driver hvc_vio_driver = {
396 .id_table = hvc_driver_table,
397 .probe = hvc_vio_probe,
398 .remove = hvc_vio_remove,
399 .name = hvc_driver_name,
400 };
401
hvc_vio_init(void)402 static int __init hvc_vio_init(void)
403 {
404 int rc;
405
406 /* Register as a vio device to receive callbacks */
407 rc = vio_register_driver(&hvc_vio_driver);
408
409 return rc;
410 }
411 module_init(hvc_vio_init); /* after drivers/char/hvc_console.c */
412
hvc_vio_exit(void)413 static void __exit hvc_vio_exit(void)
414 {
415 vio_unregister_driver(&hvc_vio_driver);
416 }
417 module_exit(hvc_vio_exit);
418
hvc_vio_init_early(void)419 void __init hvc_vio_init_early(void)
420 {
421 const __be32 *termno;
422 const char *name;
423 const struct hv_ops *ops;
424
425 /* find the boot console from /chosen/stdout */
426 if (!of_stdout)
427 return;
428 name = of_get_property(of_stdout, "name", NULL);
429 if (!name) {
430 printk(KERN_WARNING "stdout node missing 'name' property!\n");
431 return;
432 }
433
434 /* Check if it's a virtual terminal */
435 if (strncmp(name, "vty", 3) != 0)
436 return;
437 termno = of_get_property(of_stdout, "reg", NULL);
438 if (termno == NULL)
439 return;
440 hvterm_priv0.termno = of_read_number(termno, 1);
441 spin_lock_init(&hvterm_priv0.buf_lock);
442 hvterm_privs[0] = &hvterm_priv0;
443
444 /* Check the protocol */
445 if (of_device_is_compatible(of_stdout, "hvterm1")) {
446 hvterm_priv0.proto = HV_PROTOCOL_RAW;
447 ops = &hvterm_raw_ops;
448 }
449 else if (of_device_is_compatible(of_stdout, "hvterm-protocol")) {
450 hvterm_priv0.proto = HV_PROTOCOL_HVSI;
451 ops = &hvterm_hvsi_ops;
452 hvsilib_init(&hvterm_priv0.hvsi, hvc_get_chars, hvc_put_chars,
453 hvterm_priv0.termno, 1);
454 /* HVSI, perform the handshake now */
455 hvsilib_establish(&hvterm_priv0.hvsi);
456 } else
457 return;
458 udbg_putc = udbg_hvc_putc;
459 udbg_getc = udbg_hvc_getc;
460 udbg_getc_poll = udbg_hvc_getc_poll;
461 #ifdef HVC_OLD_HVSI
462 /* When using the old HVSI driver don't register the HVC
463 * backend for HVSI, only do udbg
464 */
465 if (hvterm_priv0.proto == HV_PROTOCOL_HVSI)
466 return;
467 #endif
468 /* Check whether the user has requested a different console. */
469 if (!strstr(boot_command_line, "console="))
470 add_preferred_console("hvc", 0, NULL);
471 hvc_instantiate(0, 0, ops);
472 }
473
474 /* call this from early_init() for a working debug console on
475 * vterm capable LPAR machines
476 */
477 #ifdef CONFIG_PPC_EARLY_DEBUG_LPAR
udbg_init_debug_lpar(void)478 void __init udbg_init_debug_lpar(void)
479 {
480 hvterm_privs[0] = &hvterm_priv0;
481 hvterm_priv0.termno = 0;
482 hvterm_priv0.proto = HV_PROTOCOL_RAW;
483 spin_lock_init(&hvterm_priv0.buf_lock);
484 udbg_putc = udbg_hvc_putc;
485 udbg_getc = udbg_hvc_getc;
486 udbg_getc_poll = udbg_hvc_getc_poll;
487 }
488 #endif /* CONFIG_PPC_EARLY_DEBUG_LPAR */
489
490 #ifdef CONFIG_PPC_EARLY_DEBUG_LPAR_HVSI
udbg_init_debug_lpar_hvsi(void)491 void __init udbg_init_debug_lpar_hvsi(void)
492 {
493 hvterm_privs[0] = &hvterm_priv0;
494 hvterm_priv0.termno = CONFIG_PPC_EARLY_DEBUG_HVSI_VTERMNO;
495 hvterm_priv0.proto = HV_PROTOCOL_HVSI;
496 spin_lock_init(&hvterm_priv0.buf_lock);
497 udbg_putc = udbg_hvc_putc;
498 udbg_getc = udbg_hvc_getc;
499 udbg_getc_poll = udbg_hvc_getc_poll;
500 hvsilib_init(&hvterm_priv0.hvsi, hvc_get_chars, hvc_put_chars,
501 hvterm_priv0.termno, 1);
502 hvsilib_establish(&hvterm_priv0.hvsi);
503 }
504 #endif /* CONFIG_PPC_EARLY_DEBUG_LPAR_HVSI */
505