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 52 #include "hvc_console.h" 53 54 static const char hvc_driver_name[] = "hvc_console"; 55 56 static struct vio_device_id hvc_driver_table[] = { 57 {"serial", "hvterm1"}, 58 #ifndef HVC_OLD_HVSI 59 {"serial", "hvterm-protocol"}, 60 #endif 61 { "", "" } 62 }; 63 MODULE_DEVICE_TABLE(vio, hvc_driver_table); 64 65 typedef enum hv_protocol { 66 HV_PROTOCOL_RAW, 67 HV_PROTOCOL_HVSI 68 } hv_protocol_t; 69 70 struct hvterm_priv { 71 u32 termno; /* HV term number */ 72 hv_protocol_t proto; /* Raw data or HVSI packets */ 73 struct hvsi_priv hvsi; /* HVSI specific data */ 74 spinlock_t buf_lock; 75 char buf[SIZE_VIO_GET_CHARS]; 76 int left; 77 int offset; 78 }; 79 static struct hvterm_priv *hvterm_privs[MAX_NR_HVC_CONSOLES]; 80 /* For early boot console */ 81 static struct hvterm_priv hvterm_priv0; 82 83 static int hvterm_raw_get_chars(uint32_t vtermno, char *buf, int count) 84 { 85 struct hvterm_priv *pv = hvterm_privs[vtermno]; 86 unsigned long i; 87 unsigned long flags; 88 int got; 89 90 if (WARN_ON(!pv)) 91 return 0; 92 93 spin_lock_irqsave(&pv->buf_lock, flags); 94 95 if (pv->left == 0) { 96 pv->offset = 0; 97 pv->left = hvc_get_chars(pv->termno, pv->buf, count); 98 99 /* 100 * Work around a HV bug where it gives us a null 101 * after every \r. -- paulus 102 */ 103 for (i = 1; i < pv->left; ++i) { 104 if (pv->buf[i] == 0 && pv->buf[i-1] == '\r') { 105 --pv->left; 106 if (i < pv->left) { 107 memmove(&pv->buf[i], &pv->buf[i+1], 108 pv->left - i); 109 } 110 } 111 } 112 } 113 114 got = min(count, pv->left); 115 memcpy(buf, &pv->buf[pv->offset], got); 116 pv->offset += got; 117 pv->left -= got; 118 119 spin_unlock_irqrestore(&pv->buf_lock, flags); 120 121 return got; 122 } 123 124 static int hvterm_raw_put_chars(uint32_t vtermno, const char *buf, int count) 125 { 126 struct hvterm_priv *pv = hvterm_privs[vtermno]; 127 128 if (WARN_ON(!pv)) 129 return 0; 130 131 return hvc_put_chars(pv->termno, buf, count); 132 } 133 134 static const struct hv_ops hvterm_raw_ops = { 135 .get_chars = hvterm_raw_get_chars, 136 .put_chars = hvterm_raw_put_chars, 137 .notifier_add = notifier_add_irq, 138 .notifier_del = notifier_del_irq, 139 .notifier_hangup = notifier_hangup_irq, 140 }; 141 142 static int hvterm_hvsi_get_chars(uint32_t vtermno, char *buf, int count) 143 { 144 struct hvterm_priv *pv = hvterm_privs[vtermno]; 145 146 if (WARN_ON(!pv)) 147 return 0; 148 149 return hvsilib_get_chars(&pv->hvsi, buf, count); 150 } 151 152 static int hvterm_hvsi_put_chars(uint32_t vtermno, const char *buf, int count) 153 { 154 struct hvterm_priv *pv = hvterm_privs[vtermno]; 155 156 if (WARN_ON(!pv)) 157 return 0; 158 159 return hvsilib_put_chars(&pv->hvsi, buf, count); 160 } 161 162 static int hvterm_hvsi_open(struct hvc_struct *hp, int data) 163 { 164 struct hvterm_priv *pv = hvterm_privs[hp->vtermno]; 165 int rc; 166 167 pr_devel("HVSI@%x: open !\n", pv->termno); 168 169 rc = notifier_add_irq(hp, data); 170 if (rc) 171 return rc; 172 173 return hvsilib_open(&pv->hvsi, hp); 174 } 175 176 static void hvterm_hvsi_close(struct hvc_struct *hp, int data) 177 { 178 struct hvterm_priv *pv = hvterm_privs[hp->vtermno]; 179 180 pr_devel("HVSI@%x: do close !\n", pv->termno); 181 182 hvsilib_close(&pv->hvsi, hp); 183 184 notifier_del_irq(hp, data); 185 } 186 187 void hvterm_hvsi_hangup(struct hvc_struct *hp, int data) 188 { 189 struct hvterm_priv *pv = hvterm_privs[hp->vtermno]; 190 191 pr_devel("HVSI@%x: do hangup !\n", pv->termno); 192 193 hvsilib_close(&pv->hvsi, hp); 194 195 notifier_hangup_irq(hp, data); 196 } 197 198 static int hvterm_hvsi_tiocmget(struct hvc_struct *hp) 199 { 200 struct hvterm_priv *pv = hvterm_privs[hp->vtermno]; 201 202 if (!pv) 203 return -EINVAL; 204 return pv->hvsi.mctrl; 205 } 206 207 static int hvterm_hvsi_tiocmset(struct hvc_struct *hp, unsigned int set, 208 unsigned int clear) 209 { 210 struct hvterm_priv *pv = hvterm_privs[hp->vtermno]; 211 212 pr_devel("HVSI@%x: Set modem control, set=%x,clr=%x\n", 213 pv->termno, set, clear); 214 215 if (set & TIOCM_DTR) 216 hvsilib_write_mctrl(&pv->hvsi, 1); 217 else if (clear & TIOCM_DTR) 218 hvsilib_write_mctrl(&pv->hvsi, 0); 219 220 return 0; 221 } 222 223 static const struct hv_ops hvterm_hvsi_ops = { 224 .get_chars = hvterm_hvsi_get_chars, 225 .put_chars = hvterm_hvsi_put_chars, 226 .notifier_add = hvterm_hvsi_open, 227 .notifier_del = hvterm_hvsi_close, 228 .notifier_hangup = hvterm_hvsi_hangup, 229 .tiocmget = hvterm_hvsi_tiocmget, 230 .tiocmset = hvterm_hvsi_tiocmset, 231 }; 232 233 static void udbg_hvc_putc(char c) 234 { 235 int count = -1; 236 237 if (!hvterm_privs[0]) 238 return; 239 240 if (c == '\n') 241 udbg_hvc_putc('\r'); 242 243 do { 244 switch(hvterm_privs[0]->proto) { 245 case HV_PROTOCOL_RAW: 246 count = hvterm_raw_put_chars(0, &c, 1); 247 break; 248 case HV_PROTOCOL_HVSI: 249 count = hvterm_hvsi_put_chars(0, &c, 1); 250 break; 251 } 252 } while(count == 0); 253 } 254 255 static int udbg_hvc_getc_poll(void) 256 { 257 int rc = 0; 258 char c; 259 260 if (!hvterm_privs[0]) 261 return -1; 262 263 switch(hvterm_privs[0]->proto) { 264 case HV_PROTOCOL_RAW: 265 rc = hvterm_raw_get_chars(0, &c, 1); 266 break; 267 case HV_PROTOCOL_HVSI: 268 rc = hvterm_hvsi_get_chars(0, &c, 1); 269 break; 270 } 271 if (!rc) 272 return -1; 273 return c; 274 } 275 276 static int udbg_hvc_getc(void) 277 { 278 int ch; 279 280 if (!hvterm_privs[0]) 281 return -1; 282 283 for (;;) { 284 ch = udbg_hvc_getc_poll(); 285 if (ch == -1) { 286 /* This shouldn't be needed...but... */ 287 volatile unsigned long delay; 288 for (delay=0; delay < 2000000; delay++) 289 ; 290 } else { 291 return ch; 292 } 293 } 294 } 295 296 static int hvc_vio_probe(struct vio_dev *vdev, 297 const struct vio_device_id *id) 298 { 299 const struct hv_ops *ops; 300 struct hvc_struct *hp; 301 struct hvterm_priv *pv; 302 hv_protocol_t proto; 303 int i, termno = -1; 304 305 /* probed with invalid parameters. */ 306 if (!vdev || !id) 307 return -EPERM; 308 309 if (of_device_is_compatible(vdev->dev.of_node, "hvterm1")) { 310 proto = HV_PROTOCOL_RAW; 311 ops = &hvterm_raw_ops; 312 } else if (of_device_is_compatible(vdev->dev.of_node, "hvterm-protocol")) { 313 proto = HV_PROTOCOL_HVSI; 314 ops = &hvterm_hvsi_ops; 315 } else { 316 pr_err("hvc_vio: Unknown protocol for %s\n", vdev->dev.of_node->full_name); 317 return -ENXIO; 318 } 319 320 pr_devel("hvc_vio_probe() device %s, using %s protocol\n", 321 vdev->dev.of_node->full_name, 322 proto == HV_PROTOCOL_RAW ? "raw" : "hvsi"); 323 324 /* Is it our boot one ? */ 325 if (hvterm_privs[0] == &hvterm_priv0 && 326 vdev->unit_address == hvterm_priv0.termno) { 327 pv = hvterm_privs[0]; 328 termno = 0; 329 pr_devel("->boot console, using termno 0\n"); 330 } 331 /* nope, allocate a new one */ 332 else { 333 for (i = 0; i < MAX_NR_HVC_CONSOLES && termno < 0; i++) 334 if (!hvterm_privs[i]) 335 termno = i; 336 pr_devel("->non-boot console, using termno %d\n", termno); 337 if (termno < 0) 338 return -ENODEV; 339 pv = kzalloc(sizeof(struct hvterm_priv), GFP_KERNEL); 340 if (!pv) 341 return -ENOMEM; 342 pv->termno = vdev->unit_address; 343 pv->proto = proto; 344 spin_lock_init(&pv->buf_lock); 345 hvterm_privs[termno] = pv; 346 hvsilib_init(&pv->hvsi, hvc_get_chars, hvc_put_chars, 347 pv->termno, 0); 348 } 349 350 hp = hvc_alloc(termno, vdev->irq, ops, MAX_VIO_PUT_CHARS); 351 if (IS_ERR(hp)) 352 return PTR_ERR(hp); 353 dev_set_drvdata(&vdev->dev, hp); 354 355 /* register udbg if it's not there already for console 0 */ 356 if (hp->index == 0 && !udbg_putc) { 357 udbg_putc = udbg_hvc_putc; 358 udbg_getc = udbg_hvc_getc; 359 udbg_getc_poll = udbg_hvc_getc_poll; 360 } 361 362 return 0; 363 } 364 365 static int hvc_vio_remove(struct vio_dev *vdev) 366 { 367 struct hvc_struct *hp = dev_get_drvdata(&vdev->dev); 368 int rc, termno; 369 370 termno = hp->vtermno; 371 rc = hvc_remove(hp); 372 if (rc == 0) { 373 if (hvterm_privs[termno] != &hvterm_priv0) 374 kfree(hvterm_privs[termno]); 375 hvterm_privs[termno] = NULL; 376 } 377 return rc; 378 } 379 380 static struct vio_driver hvc_vio_driver = { 381 .id_table = hvc_driver_table, 382 .probe = hvc_vio_probe, 383 .remove = hvc_vio_remove, 384 .name = hvc_driver_name, 385 }; 386 387 static int __init hvc_vio_init(void) 388 { 389 int rc; 390 391 /* Register as a vio device to receive callbacks */ 392 rc = vio_register_driver(&hvc_vio_driver); 393 394 return rc; 395 } 396 module_init(hvc_vio_init); /* after drivers/char/hvc_console.c */ 397 398 static void __exit hvc_vio_exit(void) 399 { 400 vio_unregister_driver(&hvc_vio_driver); 401 } 402 module_exit(hvc_vio_exit); 403 404 void __init hvc_vio_init_early(void) 405 { 406 struct device_node *stdout_node; 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_chosen) 413 return; 414 name = of_get_property(of_chosen, "linux,stdout-path", NULL); 415 if (name == NULL) 416 return; 417 stdout_node = of_find_node_by_path(name); 418 if (!stdout_node) 419 return; 420 name = of_get_property(stdout_node, "name", NULL); 421 if (!name) { 422 printk(KERN_WARNING "stdout node missing 'name' property!\n"); 423 goto out; 424 } 425 426 /* Check if it's a virtual terminal */ 427 if (strncmp(name, "vty", 3) != 0) 428 goto out; 429 termno = of_get_property(stdout_node, "reg", NULL); 430 if (termno == NULL) 431 goto out; 432 hvterm_priv0.termno = of_read_number(termno, 1); 433 spin_lock_init(&hvterm_priv0.buf_lock); 434 hvterm_privs[0] = &hvterm_priv0; 435 436 /* Check the protocol */ 437 if (of_device_is_compatible(stdout_node, "hvterm1")) { 438 hvterm_priv0.proto = HV_PROTOCOL_RAW; 439 ops = &hvterm_raw_ops; 440 } 441 else if (of_device_is_compatible(stdout_node, "hvterm-protocol")) { 442 hvterm_priv0.proto = HV_PROTOCOL_HVSI; 443 ops = &hvterm_hvsi_ops; 444 hvsilib_init(&hvterm_priv0.hvsi, hvc_get_chars, hvc_put_chars, 445 hvterm_priv0.termno, 1); 446 /* HVSI, perform the handshake now */ 447 hvsilib_establish(&hvterm_priv0.hvsi); 448 } else 449 goto out; 450 udbg_putc = udbg_hvc_putc; 451 udbg_getc = udbg_hvc_getc; 452 udbg_getc_poll = udbg_hvc_getc_poll; 453 #ifdef HVC_OLD_HVSI 454 /* When using the old HVSI driver don't register the HVC 455 * backend for HVSI, only do udbg 456 */ 457 if (hvterm_priv0.proto == HV_PROTOCOL_HVSI) 458 goto out; 459 #endif 460 add_preferred_console("hvc", 0, NULL); 461 hvc_instantiate(0, 0, ops); 462 out: 463 of_node_put(stdout_node); 464 } 465 466 /* call this from early_init() for a working debug console on 467 * vterm capable LPAR machines 468 */ 469 #ifdef CONFIG_PPC_EARLY_DEBUG_LPAR 470 void __init udbg_init_debug_lpar(void) 471 { 472 hvterm_privs[0] = &hvterm_priv0; 473 hvterm_priv0.termno = 0; 474 hvterm_priv0.proto = HV_PROTOCOL_RAW; 475 spin_lock_init(&hvterm_priv0.buf_lock); 476 udbg_putc = udbg_hvc_putc; 477 udbg_getc = udbg_hvc_getc; 478 udbg_getc_poll = udbg_hvc_getc_poll; 479 } 480 #endif /* CONFIG_PPC_EARLY_DEBUG_LPAR */ 481 482 #ifdef CONFIG_PPC_EARLY_DEBUG_LPAR_HVSI 483 void __init udbg_init_debug_lpar_hvsi(void) 484 { 485 hvterm_privs[0] = &hvterm_priv0; 486 hvterm_priv0.termno = CONFIG_PPC_EARLY_DEBUG_HVSI_VTERMNO; 487 hvterm_priv0.proto = HV_PROTOCOL_HVSI; 488 spin_lock_init(&hvterm_priv0.buf_lock); 489 udbg_putc = udbg_hvc_putc; 490 udbg_getc = udbg_hvc_getc; 491 udbg_getc_poll = udbg_hvc_getc_poll; 492 hvsilib_init(&hvterm_priv0.hvsi, hvc_get_chars, hvc_put_chars, 493 hvterm_priv0.termno, 1); 494 hvsilib_establish(&hvterm_priv0.hvsi); 495 } 496 #endif /* CONFIG_PPC_EARLY_DEBUG_LPAR_HVSI */ 497