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
hvterm_raw_put_chars(uint32_t vtermno,const char * buf,int count)125 static int hvterm_raw_put_chars(uint32_t vtermno, const char *buf, int count)
126 {
127 struct hvterm_priv *pv = hvterm_privs[vtermno];
128
129 if (WARN_ON(!pv))
130 return 0;
131
132 return hvc_put_chars(pv->termno, buf, count);
133 }
134
135 static const struct hv_ops hvterm_raw_ops = {
136 .get_chars = hvterm_raw_get_chars,
137 .put_chars = hvterm_raw_put_chars,
138 .notifier_add = notifier_add_irq,
139 .notifier_del = notifier_del_irq,
140 .notifier_hangup = notifier_hangup_irq,
141 };
142
hvterm_hvsi_get_chars(uint32_t vtermno,char * buf,int count)143 static int hvterm_hvsi_get_chars(uint32_t vtermno, char *buf, int count)
144 {
145 struct hvterm_priv *pv = hvterm_privs[vtermno];
146
147 if (WARN_ON(!pv))
148 return 0;
149
150 return hvsilib_get_chars(&pv->hvsi, buf, count);
151 }
152
hvterm_hvsi_put_chars(uint32_t vtermno,const char * buf,int count)153 static int hvterm_hvsi_put_chars(uint32_t vtermno, const char *buf, int count)
154 {
155 struct hvterm_priv *pv = hvterm_privs[vtermno];
156
157 if (WARN_ON(!pv))
158 return 0;
159
160 return hvsilib_put_chars(&pv->hvsi, buf, count);
161 }
162
hvterm_hvsi_open(struct hvc_struct * hp,int data)163 static int hvterm_hvsi_open(struct hvc_struct *hp, int data)
164 {
165 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
166 int rc;
167
168 pr_devel("HVSI@%x: open !\n", pv->termno);
169
170 rc = notifier_add_irq(hp, data);
171 if (rc)
172 return rc;
173
174 return hvsilib_open(&pv->hvsi, hp);
175 }
176
hvterm_hvsi_close(struct hvc_struct * hp,int data)177 static void hvterm_hvsi_close(struct hvc_struct *hp, int data)
178 {
179 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
180
181 pr_devel("HVSI@%x: do close !\n", pv->termno);
182
183 hvsilib_close(&pv->hvsi, hp);
184
185 notifier_del_irq(hp, data);
186 }
187
hvterm_hvsi_hangup(struct hvc_struct * hp,int data)188 void hvterm_hvsi_hangup(struct hvc_struct *hp, int data)
189 {
190 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
191
192 pr_devel("HVSI@%x: do hangup !\n", pv->termno);
193
194 hvsilib_close(&pv->hvsi, hp);
195
196 notifier_hangup_irq(hp, data);
197 }
198
hvterm_hvsi_tiocmget(struct hvc_struct * hp)199 static int hvterm_hvsi_tiocmget(struct hvc_struct *hp)
200 {
201 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
202
203 if (!pv)
204 return -EINVAL;
205 return pv->hvsi.mctrl;
206 }
207
hvterm_hvsi_tiocmset(struct hvc_struct * hp,unsigned int set,unsigned int clear)208 static int hvterm_hvsi_tiocmset(struct hvc_struct *hp, unsigned int set,
209 unsigned int clear)
210 {
211 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
212
213 pr_devel("HVSI@%x: Set modem control, set=%x,clr=%x\n",
214 pv->termno, set, clear);
215
216 if (set & TIOCM_DTR)
217 hvsilib_write_mctrl(&pv->hvsi, 1);
218 else if (clear & TIOCM_DTR)
219 hvsilib_write_mctrl(&pv->hvsi, 0);
220
221 return 0;
222 }
223
224 static const struct hv_ops hvterm_hvsi_ops = {
225 .get_chars = hvterm_hvsi_get_chars,
226 .put_chars = hvterm_hvsi_put_chars,
227 .notifier_add = hvterm_hvsi_open,
228 .notifier_del = hvterm_hvsi_close,
229 .notifier_hangup = hvterm_hvsi_hangup,
230 .tiocmget = hvterm_hvsi_tiocmget,
231 .tiocmset = hvterm_hvsi_tiocmset,
232 };
233
udbg_hvc_putc(char c)234 static void udbg_hvc_putc(char c)
235 {
236 int count = -1;
237
238 if (!hvterm_privs[0])
239 return;
240
241 if (c == '\n')
242 udbg_hvc_putc('\r');
243
244 do {
245 switch(hvterm_privs[0]->proto) {
246 case HV_PROTOCOL_RAW:
247 count = hvterm_raw_put_chars(0, &c, 1);
248 break;
249 case HV_PROTOCOL_HVSI:
250 count = hvterm_hvsi_put_chars(0, &c, 1);
251 break;
252 }
253 } while(count == 0);
254 }
255
udbg_hvc_getc_poll(void)256 static int udbg_hvc_getc_poll(void)
257 {
258 int rc = 0;
259 char c;
260
261 if (!hvterm_privs[0])
262 return -1;
263
264 switch(hvterm_privs[0]->proto) {
265 case HV_PROTOCOL_RAW:
266 rc = hvterm_raw_get_chars(0, &c, 1);
267 break;
268 case HV_PROTOCOL_HVSI:
269 rc = hvterm_hvsi_get_chars(0, &c, 1);
270 break;
271 }
272 if (!rc)
273 return -1;
274 return c;
275 }
276
udbg_hvc_getc(void)277 static int udbg_hvc_getc(void)
278 {
279 int ch;
280
281 if (!hvterm_privs[0])
282 return -1;
283
284 for (;;) {
285 ch = udbg_hvc_getc_poll();
286 if (ch == -1) {
287 /* This shouldn't be needed...but... */
288 volatile unsigned long delay;
289 for (delay=0; delay < 2000000; delay++)
290 ;
291 } else {
292 return ch;
293 }
294 }
295 }
296
hvc_vio_probe(struct vio_dev * vdev,const struct vio_device_id * id)297 static int hvc_vio_probe(struct vio_dev *vdev,
298 const struct vio_device_id *id)
299 {
300 const struct hv_ops *ops;
301 struct hvc_struct *hp;
302 struct hvterm_priv *pv;
303 hv_protocol_t proto;
304 int i, termno = -1;
305
306 /* probed with invalid parameters. */
307 if (!vdev || !id)
308 return -EPERM;
309
310 if (of_device_is_compatible(vdev->dev.of_node, "hvterm1")) {
311 proto = HV_PROTOCOL_RAW;
312 ops = &hvterm_raw_ops;
313 } else if (of_device_is_compatible(vdev->dev.of_node, "hvterm-protocol")) {
314 proto = HV_PROTOCOL_HVSI;
315 ops = &hvterm_hvsi_ops;
316 } else {
317 pr_err("hvc_vio: Unknown protocol for %s\n", vdev->dev.of_node->full_name);
318 return -ENXIO;
319 }
320
321 pr_devel("hvc_vio_probe() device %s, using %s protocol\n",
322 vdev->dev.of_node->full_name,
323 proto == HV_PROTOCOL_RAW ? "raw" : "hvsi");
324
325 /* Is it our boot one ? */
326 if (hvterm_privs[0] == &hvterm_priv0 &&
327 vdev->unit_address == hvterm_priv0.termno) {
328 pv = hvterm_privs[0];
329 termno = 0;
330 pr_devel("->boot console, using termno 0\n");
331 }
332 /* nope, allocate a new one */
333 else {
334 for (i = 0; i < MAX_NR_HVC_CONSOLES && termno < 0; i++)
335 if (!hvterm_privs[i])
336 termno = i;
337 pr_devel("->non-boot console, using termno %d\n", termno);
338 if (termno < 0)
339 return -ENODEV;
340 pv = kzalloc(sizeof(struct hvterm_priv), GFP_KERNEL);
341 if (!pv)
342 return -ENOMEM;
343 pv->termno = vdev->unit_address;
344 pv->proto = proto;
345 spin_lock_init(&pv->buf_lock);
346 hvterm_privs[termno] = pv;
347 hvsilib_init(&pv->hvsi, hvc_get_chars, hvc_put_chars,
348 pv->termno, 0);
349 }
350
351 hp = hvc_alloc(termno, vdev->irq, ops, MAX_VIO_PUT_CHARS);
352 if (IS_ERR(hp))
353 return PTR_ERR(hp);
354 dev_set_drvdata(&vdev->dev, hp);
355
356 /* register udbg if it's not there already for console 0 */
357 if (hp->index == 0 && !udbg_putc) {
358 udbg_putc = udbg_hvc_putc;
359 udbg_getc = udbg_hvc_getc;
360 udbg_getc_poll = udbg_hvc_getc_poll;
361 }
362
363 return 0;
364 }
365
hvc_vio_remove(struct vio_dev * vdev)366 static int hvc_vio_remove(struct vio_dev *vdev)
367 {
368 struct hvc_struct *hp = dev_get_drvdata(&vdev->dev);
369 int rc, termno;
370
371 termno = hp->vtermno;
372 rc = hvc_remove(hp);
373 if (rc == 0) {
374 if (hvterm_privs[termno] != &hvterm_priv0)
375 kfree(hvterm_privs[termno]);
376 hvterm_privs[termno] = NULL;
377 }
378 return rc;
379 }
380
381 static struct vio_driver hvc_vio_driver = {
382 .id_table = hvc_driver_table,
383 .probe = hvc_vio_probe,
384 .remove = hvc_vio_remove,
385 .name = hvc_driver_name,
386 };
387
hvc_vio_init(void)388 static int __init hvc_vio_init(void)
389 {
390 int rc;
391
392 /* Register as a vio device to receive callbacks */
393 rc = vio_register_driver(&hvc_vio_driver);
394
395 return rc;
396 }
397 module_init(hvc_vio_init); /* after drivers/char/hvc_console.c */
398
hvc_vio_exit(void)399 static void __exit hvc_vio_exit(void)
400 {
401 vio_unregister_driver(&hvc_vio_driver);
402 }
403 module_exit(hvc_vio_exit);
404
hvc_vio_init_early(void)405 void __init hvc_vio_init_early(void)
406 {
407 const __be32 *termno;
408 const char *name;
409 const struct hv_ops *ops;
410
411 /* find the boot console from /chosen/stdout */
412 if (!of_stdout)
413 return;
414 name = of_get_property(of_stdout, "name", NULL);
415 if (!name) {
416 printk(KERN_WARNING "stdout node missing 'name' property!\n");
417 return;
418 }
419
420 /* Check if it's a virtual terminal */
421 if (strncmp(name, "vty", 3) != 0)
422 return;
423 termno = of_get_property(of_stdout, "reg", NULL);
424 if (termno == NULL)
425 return;
426 hvterm_priv0.termno = of_read_number(termno, 1);
427 spin_lock_init(&hvterm_priv0.buf_lock);
428 hvterm_privs[0] = &hvterm_priv0;
429
430 /* Check the protocol */
431 if (of_device_is_compatible(of_stdout, "hvterm1")) {
432 hvterm_priv0.proto = HV_PROTOCOL_RAW;
433 ops = &hvterm_raw_ops;
434 }
435 else if (of_device_is_compatible(of_stdout, "hvterm-protocol")) {
436 hvterm_priv0.proto = HV_PROTOCOL_HVSI;
437 ops = &hvterm_hvsi_ops;
438 hvsilib_init(&hvterm_priv0.hvsi, hvc_get_chars, hvc_put_chars,
439 hvterm_priv0.termno, 1);
440 /* HVSI, perform the handshake now */
441 hvsilib_establish(&hvterm_priv0.hvsi);
442 } else
443 return;
444 udbg_putc = udbg_hvc_putc;
445 udbg_getc = udbg_hvc_getc;
446 udbg_getc_poll = udbg_hvc_getc_poll;
447 #ifdef HVC_OLD_HVSI
448 /* When using the old HVSI driver don't register the HVC
449 * backend for HVSI, only do udbg
450 */
451 if (hvterm_priv0.proto == HV_PROTOCOL_HVSI)
452 return;
453 #endif
454 /* Check whether the user has requested a different console. */
455 if (!strstr(boot_command_line, "console="))
456 add_preferred_console("hvc", 0, NULL);
457 hvc_instantiate(0, 0, ops);
458 }
459
460 /* call this from early_init() for a working debug console on
461 * vterm capable LPAR machines
462 */
463 #ifdef CONFIG_PPC_EARLY_DEBUG_LPAR
udbg_init_debug_lpar(void)464 void __init udbg_init_debug_lpar(void)
465 {
466 hvterm_privs[0] = &hvterm_priv0;
467 hvterm_priv0.termno = 0;
468 hvterm_priv0.proto = HV_PROTOCOL_RAW;
469 spin_lock_init(&hvterm_priv0.buf_lock);
470 udbg_putc = udbg_hvc_putc;
471 udbg_getc = udbg_hvc_getc;
472 udbg_getc_poll = udbg_hvc_getc_poll;
473 }
474 #endif /* CONFIG_PPC_EARLY_DEBUG_LPAR */
475
476 #ifdef CONFIG_PPC_EARLY_DEBUG_LPAR_HVSI
udbg_init_debug_lpar_hvsi(void)477 void __init udbg_init_debug_lpar_hvsi(void)
478 {
479 hvterm_privs[0] = &hvterm_priv0;
480 hvterm_priv0.termno = CONFIG_PPC_EARLY_DEBUG_HVSI_VTERMNO;
481 hvterm_priv0.proto = HV_PROTOCOL_HVSI;
482 spin_lock_init(&hvterm_priv0.buf_lock);
483 udbg_putc = udbg_hvc_putc;
484 udbg_getc = udbg_hvc_getc;
485 udbg_getc_poll = udbg_hvc_getc_poll;
486 hvsilib_init(&hvterm_priv0.hvsi, hvc_get_chars, hvc_put_chars,
487 hvterm_priv0.termno, 1);
488 hvsilib_establish(&hvterm_priv0.hvsi);
489 }
490 #endif /* CONFIG_PPC_EARLY_DEBUG_LPAR_HVSI */
491