Warning: That file was not part of the compilation database. It may have many parsing errors.

1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * vio driver interface to hvc_console.c
4 *
5 * This code was moved here to allow the remaining code to be reused as a
6 * generic polling mode with semi-reliable transport driver core to the
7 * console and tty subsystems.
8 *
9 *
10 * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
11 * Copyright (C) 2001 Paul Mackerras <paulus@au.ibm.com>, IBM
12 * Copyright (C) 2004 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
13 * Copyright (C) 2004 IBM Corporation
14 *
15 * Additional Author(s):
16 * Ryan S. Arnold <rsa@us.ibm.com>
17 *
18 * TODO:
19 *
20 * - handle error in sending hvsi protocol packets
21 * - retry nego on subsequent sends ?
22 */
23
24#undef DEBUG
25
26#include <linux/types.h>
27#include <linux/init.h>
28#include <linux/delay.h>
29#include <linux/slab.h>
30#include <linux/console.h>
31
32#include <asm/hvconsole.h>
33#include <asm/vio.h>
34#include <asm/prom.h>
35#include <asm/hvsi.h>
36#include <asm/udbg.h>
37#include <asm/machdep.h>
38
39#include "hvc_console.h"
40
41static const char hvc_driver_name[] = "hvc_console";
42
43static const struct vio_device_id hvc_driver_table[] = {
44 {"serial", "hvterm1"},
45#ifndef HVC_OLD_HVSI
46 {"serial", "hvterm-protocol"},
47#endif
48 { "", "" }
49};
50
51typedef enum hv_protocol {
52 HV_PROTOCOL_RAW,
53 HV_PROTOCOL_HVSI
54} hv_protocol_t;
55
56struct hvterm_priv {
57 u32 termno; /* HV term number */
58 hv_protocol_t proto; /* Raw data or HVSI packets */
59 struct hvsi_priv hvsi; /* HVSI specific data */
60 spinlock_t buf_lock;
61 char buf[SIZE_VIO_GET_CHARS];
62 int left;
63 int offset;
64};
65static struct hvterm_priv *hvterm_privs[MAX_NR_HVC_CONSOLES];
66/* For early boot console */
67static struct hvterm_priv hvterm_priv0;
68
69static int hvterm_raw_get_chars(uint32_t vtermno, char *buf, int count)
70{
71 struct hvterm_priv *pv = hvterm_privs[vtermno];
72 unsigned long i;
73 unsigned long flags;
74 int got;
75
76 if (WARN_ON(!pv))
77 return 0;
78
79 spin_lock_irqsave(&pv->buf_lock, flags);
80
81 if (pv->left == 0) {
82 pv->offset = 0;
83 pv->left = hvc_get_chars(pv->termno, pv->buf, count);
84
85 /*
86 * Work around a HV bug where it gives us a null
87 * after every \r. -- paulus
88 */
89 for (i = 1; i < pv->left; ++i) {
90 if (pv->buf[i] == 0 && pv->buf[i-1] == '\r') {
91 --pv->left;
92 if (i < pv->left) {
93 memmove(&pv->buf[i], &pv->buf[i+1],
94 pv->left - i);
95 }
96 }
97 }
98 }
99
100 got = min(count, pv->left);
101 memcpy(buf, &pv->buf[pv->offset], got);
102 pv->offset += got;
103 pv->left -= got;
104
105 spin_unlock_irqrestore(&pv->buf_lock, flags);
106
107 return got;
108}
109
110static int hvterm_raw_put_chars(uint32_t vtermno, const char *buf, int count)
111{
112 struct hvterm_priv *pv = hvterm_privs[vtermno];
113
114 if (WARN_ON(!pv))
115 return 0;
116
117 return hvc_put_chars(pv->termno, buf, count);
118}
119
120static const struct hv_ops hvterm_raw_ops = {
121 .get_chars = hvterm_raw_get_chars,
122 .put_chars = hvterm_raw_put_chars,
123 .notifier_add = notifier_add_irq,
124 .notifier_del = notifier_del_irq,
125 .notifier_hangup = notifier_hangup_irq,
126};
127
128static int hvterm_hvsi_get_chars(uint32_t vtermno, char *buf, int count)
129{
130 struct hvterm_priv *pv = hvterm_privs[vtermno];
131
132 if (WARN_ON(!pv))
133 return 0;
134
135 return hvsilib_get_chars(&pv->hvsi, buf, count);
136}
137
138static int hvterm_hvsi_put_chars(uint32_t vtermno, const char *buf, int count)
139{
140 struct hvterm_priv *pv = hvterm_privs[vtermno];
141
142 if (WARN_ON(!pv))
143 return 0;
144
145 return hvsilib_put_chars(&pv->hvsi, buf, count);
146}
147
148static int hvterm_hvsi_open(struct hvc_struct *hp, int data)
149{
150 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
151 int rc;
152
153 pr_devel("HVSI@%x: open !\n", pv->termno);
154
155 rc = notifier_add_irq(hp, data);
156 if (rc)
157 return rc;
158
159 return hvsilib_open(&pv->hvsi, hp);
160}
161
162static void hvterm_hvsi_close(struct hvc_struct *hp, int data)
163{
164 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
165
166 pr_devel("HVSI@%x: do close !\n", pv->termno);
167
168 hvsilib_close(&pv->hvsi, hp);
169
170 notifier_del_irq(hp, data);
171}
172
173void hvterm_hvsi_hangup(struct hvc_struct *hp, int data)
174{
175 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
176
177 pr_devel("HVSI@%x: do hangup !\n", pv->termno);
178
179 hvsilib_close(&pv->hvsi, hp);
180
181 notifier_hangup_irq(hp, data);
182}
183
184static int hvterm_hvsi_tiocmget(struct hvc_struct *hp)
185{
186 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
187
188 if (!pv)
189 return -EINVAL;
190 return pv->hvsi.mctrl;
191}
192
193static int hvterm_hvsi_tiocmset(struct hvc_struct *hp, unsigned int set,
194 unsigned int clear)
195{
196 struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
197
198 pr_devel("HVSI@%x: Set modem control, set=%x,clr=%x\n",
199 pv->termno, set, clear);
200
201 if (set & TIOCM_DTR)
202 hvsilib_write_mctrl(&pv->hvsi, 1);
203 else if (clear & TIOCM_DTR)
204 hvsilib_write_mctrl(&pv->hvsi, 0);
205
206 return 0;
207}
208
209static const struct hv_ops hvterm_hvsi_ops = {
210 .get_chars = hvterm_hvsi_get_chars,
211 .put_chars = hvterm_hvsi_put_chars,
212 .notifier_add = hvterm_hvsi_open,
213 .notifier_del = hvterm_hvsi_close,
214 .notifier_hangup = hvterm_hvsi_hangup,
215 .tiocmget = hvterm_hvsi_tiocmget,
216 .tiocmset = hvterm_hvsi_tiocmset,
217};
218
219static void udbg_hvc_putc(char c)
220{
221 int count = -1;
222
223 if (!hvterm_privs[0])
224 return;
225
226 if (c == '\n')
227 udbg_hvc_putc('\r');
228
229 do {
230 switch(hvterm_privs[0]->proto) {
231 case HV_PROTOCOL_RAW:
232 count = hvterm_raw_put_chars(0, &c, 1);
233 break;
234 case HV_PROTOCOL_HVSI:
235 count = hvterm_hvsi_put_chars(0, &c, 1);
236 break;
237 }
238 } while(count == 0);
239}
240
241static int udbg_hvc_getc_poll(void)
242{
243 int rc = 0;
244 char c;
245
246 if (!hvterm_privs[0])
247 return -1;
248
249 switch(hvterm_privs[0]->proto) {
250 case HV_PROTOCOL_RAW:
251 rc = hvterm_raw_get_chars(0, &c, 1);
252 break;
253 case HV_PROTOCOL_HVSI:
254 rc = hvterm_hvsi_get_chars(0, &c, 1);
255 break;
256 }
257 if (!rc)
258 return -1;
259 return c;
260}
261
262static int udbg_hvc_getc(void)
263{
264 int ch;
265
266 if (!hvterm_privs[0])
267 return -1;
268
269 for (;;) {
270 ch = udbg_hvc_getc_poll();
271 if (ch == -1) {
272 /* This shouldn't be needed...but... */
273 volatile unsigned long delay;
274 for (delay=0; delay < 2000000; delay++)
275 ;
276 } else {
277 return ch;
278 }
279 }
280}
281
282static int hvc_vio_probe(struct vio_dev *vdev,
283 const struct vio_device_id *id)
284{
285 const struct hv_ops *ops;
286 struct hvc_struct *hp;
287 struct hvterm_priv *pv;
288 hv_protocol_t proto;
289 int i, termno = -1;
290
291 /* probed with invalid parameters. */
292 if (!vdev || !id)
293 return -EPERM;
294
295 if (of_device_is_compatible(vdev->dev.of_node, "hvterm1")) {
296 proto = HV_PROTOCOL_RAW;
297 ops = &hvterm_raw_ops;
298 } else if (of_device_is_compatible(vdev->dev.of_node, "hvterm-protocol")) {
299 proto = HV_PROTOCOL_HVSI;
300 ops = &hvterm_hvsi_ops;
301 } else {
302 pr_err("hvc_vio: Unknown protocol for %pOF\n", vdev->dev.of_node);
303 return -ENXIO;
304 }
305
306 pr_devel("hvc_vio_probe() device %pOF, using %s protocol\n",
307 vdev->dev.of_node,
308 proto == HV_PROTOCOL_RAW ? "raw" : "hvsi");
309
310 /* Is it our boot one ? */
311 if (hvterm_privs[0] == &hvterm_priv0 &&
312 vdev->unit_address == hvterm_priv0.termno) {
313 pv = hvterm_privs[0];
314 termno = 0;
315 pr_devel("->boot console, using termno 0\n");
316 }
317 /* nope, allocate a new one */
318 else {
319 for (i = 0; i < MAX_NR_HVC_CONSOLES && termno < 0; i++)
320 if (!hvterm_privs[i])
321 termno = i;
322 pr_devel("->non-boot console, using termno %d\n", termno);
323 if (termno < 0)
324 return -ENODEV;
325 pv = kzalloc(sizeof(struct hvterm_priv), GFP_KERNEL);
326 if (!pv)
327 return -ENOMEM;
328 pv->termno = vdev->unit_address;
329 pv->proto = proto;
330 spin_lock_init(&pv->buf_lock);
331 hvterm_privs[termno] = pv;
332 hvsilib_init(&pv->hvsi, hvc_get_chars, hvc_put_chars,
333 pv->termno, 0);
334 }
335
336 hp = hvc_alloc(termno, vdev->irq, ops, MAX_VIO_PUT_CHARS);
337 if (IS_ERR(hp))
338 return PTR_ERR(hp);
339 dev_set_drvdata(&vdev->dev, hp);
340
341 /* register udbg if it's not there already for console 0 */
342 if (hp->index == 0 && !udbg_putc) {
343 udbg_putc = udbg_hvc_putc;
344 udbg_getc = udbg_hvc_getc;
345 udbg_getc_poll = udbg_hvc_getc_poll;
346 }
347
348 return 0;
349}
350
351static struct vio_driver hvc_vio_driver = {
352 .id_table = hvc_driver_table,
353 .probe = hvc_vio_probe,
354 .name = hvc_driver_name,
355 .driver = {
356 .suppress_bind_attrs = true,
357 },
358};
359
360static int __init hvc_vio_init(void)
361{
362 int rc;
363
364 /* Register as a vio device to receive callbacks */
365 rc = vio_register_driver(&hvc_vio_driver);
366
367 return rc;
368}
369device_initcall(hvc_vio_init); /* after drivers/tty/hvc/hvc_console.c */
370
371void __init hvc_vio_init_early(void)
372{
373 const __be32 *termno;
374 const struct hv_ops *ops;
375
376 /* find the boot console from /chosen/stdout */
377 /* Check if it's a virtual terminal */
378 if (!of_node_name_prefix(of_stdout, "vty"))
379 return;
380 termno = of_get_property(of_stdout, "reg", NULL);
381 if (termno == NULL)
382 return;
383 hvterm_priv0.termno = of_read_number(termno, 1);
384 spin_lock_init(&hvterm_priv0.buf_lock);
385 hvterm_privs[0] = &hvterm_priv0;
386
387 /* Check the protocol */
388 if (of_device_is_compatible(of_stdout, "hvterm1")) {
389 hvterm_priv0.proto = HV_PROTOCOL_RAW;
390 ops = &hvterm_raw_ops;
391 }
392 else if (of_device_is_compatible(of_stdout, "hvterm-protocol")) {
393 hvterm_priv0.proto = HV_PROTOCOL_HVSI;
394 ops = &hvterm_hvsi_ops;
395 hvsilib_init(&hvterm_priv0.hvsi, hvc_get_chars, hvc_put_chars,
396 hvterm_priv0.termno, 1);
397 /* HVSI, perform the handshake now */
398 hvsilib_establish(&hvterm_priv0.hvsi);
399 } else
400 return;
401 udbg_putc = udbg_hvc_putc;
402 udbg_getc = udbg_hvc_getc;
403 udbg_getc_poll = udbg_hvc_getc_poll;
404#ifdef HVC_OLD_HVSI
405 /* When using the old HVSI driver don't register the HVC
406 * backend for HVSI, only do udbg
407 */
408 if (hvterm_priv0.proto == HV_PROTOCOL_HVSI)
409 return;
410#endif
411 /* Check whether the user has requested a different console. */
412 if (!strstr(boot_command_line, "console="))
413 add_preferred_console("hvc", 0, NULL);
414 hvc_instantiate(0, 0, ops);
415}
416
417/* call this from early_init() for a working debug console on
418 * vterm capable LPAR machines
419 */
420#ifdef CONFIG_PPC_EARLY_DEBUG_LPAR
421void __init udbg_init_debug_lpar(void)
422{
423 /*
424 * If we're running as a hypervisor then we definitely can't call the
425 * hypervisor to print debug output (we *are* the hypervisor), so don't
426 * register if we detect that MSR_HV=1.
427 */
428 if (mfmsr() & MSR_HV)
429 return;
430
431 hvterm_privs[0] = &hvterm_priv0;
432 hvterm_priv0.termno = 0;
433 hvterm_priv0.proto = HV_PROTOCOL_RAW;
434 spin_lock_init(&hvterm_priv0.buf_lock);
435 udbg_putc = udbg_hvc_putc;
436 udbg_getc = udbg_hvc_getc;
437 udbg_getc_poll = udbg_hvc_getc_poll;
438}
439#endif /* CONFIG_PPC_EARLY_DEBUG_LPAR */
440
441#ifdef CONFIG_PPC_EARLY_DEBUG_LPAR_HVSI
442void __init udbg_init_debug_lpar_hvsi(void)
443{
444 /* See comment above in udbg_init_debug_lpar() */
445 if (mfmsr() & MSR_HV)
446 return;
447
448 hvterm_privs[0] = &hvterm_priv0;
449 hvterm_priv0.termno = CONFIG_PPC_EARLY_DEBUG_HVSI_VTERMNO;
450 hvterm_priv0.proto = HV_PROTOCOL_HVSI;
451 spin_lock_init(&hvterm_priv0.buf_lock);
452 udbg_putc = udbg_hvc_putc;
453 udbg_getc = udbg_hvc_getc;
454 udbg_getc_poll = udbg_hvc_getc_poll;
455 hvsilib_init(&hvterm_priv0.hvsi, hvc_get_chars, hvc_put_chars,
456 hvterm_priv0.termno, 1);
457 hvsilib_establish(&hvterm_priv0.hvsi);
458}
459#endif /* CONFIG_PPC_EARLY_DEBUG_LPAR_HVSI */
460

Warning: That file was not part of the compilation database. It may have many parsing errors.