err.no Git - linux-2.6/blob - drivers/char/hvc_iseries.c

   1 /*
   2  * iSeries vio driver interface to hvc_console.c
   3  *
   4  * This code is based heavily on hvc_vio.c and viocons.c
   5  *
   6  * Copyright (C) 2006 Stephen Rothwell, IBM Corporation
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  21  */
  22 #include <stdarg.h>
  23 #include <linux/types.h>
  24 #include <linux/init.h>
  25 #include <linux/kernel.h>
  26 #include <linux/spinlock.h>
  27 #include <linux/console.h>
  28
  29 #include <asm/hvconsole.h>
  30 #include <asm/vio.h>
  31 #include <asm/prom.h>
  32 #include <asm/firmware.h>
  33 #include <asm/iseries/vio.h>
  34 #include <asm/iseries/hv_call.h>
  35 #include <asm/iseries/hv_lp_config.h>
  36 #include <asm/iseries/hv_lp_event.h>
  37
  38 #include "hvc_console.h"
  39
  40 #define VTTY_PORTS 10
  41
  42 static DEFINE_SPINLOCK(consolelock);
  43 static DEFINE_SPINLOCK(consoleloglock);
  44
  45 static const char hvc_driver_name[] = "hvc_console";
  46
  47 #define IN_BUF_SIZE     200
  48
  49 /*
  50  * Our port information.
  51  */
  52 static struct port_info {
  53         HvLpIndex lp;
  54         u64 seq;        /* sequence number of last HV send */
  55         u64 ack;        /* last ack from HV */
  56         struct hvc_struct *hp;
  57         int in_start;
  58         int in_end;
  59         unsigned char in_buf[IN_BUF_SIZE];
  60 } port_info[VTTY_PORTS] = {
  61         [ 0 ... VTTY_PORTS - 1 ] = {
  62                 .lp = HvLpIndexInvalid
  63         }
  64 };
  65
  66 #define viochar_is_console(pi)  ((pi) == &port_info[0])
  67
  68 static struct vio_device_id hvc_driver_table[] __devinitdata = {
  69         {"serial", "IBM,iSeries-vty"},
  70         { "", "" }
  71 };
  72 MODULE_DEVICE_TABLE(vio, hvc_driver_table);
  73
  74 static void hvlog(char *fmt, ...)
  75 {
  76         int i;
  77         unsigned long flags;
  78         va_list args;
  79         static char buf[256];
  80
  81         spin_lock_irqsave(&consoleloglock, flags);
  82         va_start(args, fmt);
  83         i = vscnprintf(buf, sizeof(buf) - 1, fmt, args);
  84         va_end(args);
  85         buf[i++] = '\r';
  86         HvCall_writeLogBuffer(buf, i);
  87         spin_unlock_irqrestore(&consoleloglock, flags);
  88 }
  89
  90 /*
  91  * Initialize the common fields in a charLpEvent
  92  */
  93 static void init_data_event(struct viocharlpevent *viochar, HvLpIndex lp)
  94 {
  95         struct HvLpEvent *hev = &viochar->event;
  96
  97         memset(viochar, 0, sizeof(struct viocharlpevent));
  98
  99         hev->flags = HV_LP_EVENT_VALID | HV_LP_EVENT_DEFERRED_ACK |
 100                 HV_LP_EVENT_INT;
 101         hev->xType = HvLpEvent_Type_VirtualIo;
 102         hev->xSubtype = viomajorsubtype_chario | viochardata;
 103         hev->xSourceLp = HvLpConfig_getLpIndex();
 104         hev->xTargetLp = lp;
 105         hev->xSizeMinus1 = sizeof(struct viocharlpevent);
 106         hev->xSourceInstanceId = viopath_sourceinst(lp);
 107         hev->xTargetInstanceId = viopath_targetinst(lp);
 108 }
 109
 110 static int get_chars(uint32_t vtermno, char *buf, int count)
 111 {
 112         struct port_info *pi;
 113         int n = 0;
 114         unsigned long flags;
 115
 116         if (vtermno >= VTTY_PORTS)
 117                 return -EINVAL;
 118         if (count == 0)
 119                 return 0;
 120
 121         pi = &port_info[vtermno];
 122         spin_lock_irqsave(&consolelock, flags);
 123
 124         if (pi->in_end == 0)
 125                 goto done;
 126
 127         n = pi->in_end - pi->in_start;
 128         if (n > count)
 129                 n = count;
 130         memcpy(buf, &pi->in_buf[pi->in_start], n);
 131         pi->in_start += n;
 132         if (pi->in_start == pi->in_end) {
 133                 pi->in_start = 0;
 134                 pi->in_end = 0;
 135         }
 136 done:
 137         spin_unlock_irqrestore(&consolelock, flags);
 138         return n;
 139 }
 140
 141 static int put_chars(uint32_t vtermno, const char *buf, int count)
 142 {
 143         struct viocharlpevent *viochar;
 144         struct port_info *pi;
 145         HvLpEvent_Rc hvrc;
 146         unsigned long flags;
 147         int sent = 0;
 148
 149         if (vtermno >= VTTY_PORTS)
 150                 return -EINVAL;
 151
 152         pi = &port_info[vtermno];
 153
 154         spin_lock_irqsave(&consolelock, flags);
 155
 156         if (viochar_is_console(pi) && !viopath_isactive(pi->lp)) {
 157                 spin_lock_irqsave(&consoleloglock, flags);
 158                 HvCall_writeLogBuffer(buf, count);
 159                 spin_unlock_irqrestore(&consoleloglock, flags);
 160                 sent = count;
 161                 goto done;
 162         }
 163
 164         viochar = vio_get_event_buffer(viomajorsubtype_chario);
 165         if (viochar == NULL) {
 166                 hvlog("\n\rviocons: Can't get viochar buffer.");
 167                 goto done;
 168         }
 169
 170         while ((count > 0) && ((pi->seq - pi->ack) < VIOCHAR_WINDOW)) {
 171                 int len;
 172
 173                 len = (count > VIOCHAR_MAX_DATA) ? VIOCHAR_MAX_DATA : count;
 174
 175                 if (viochar_is_console(pi)) {
 176                         spin_lock_irqsave(&consoleloglock, flags);
 177                         HvCall_writeLogBuffer(buf, len);
 178                         spin_unlock_irqrestore(&consoleloglock, flags);
 179                 }
 180
 181                 init_data_event(viochar, pi->lp);
 182
 183                 viochar->len = len;
 184                 viochar->event.xCorrelationToken = pi->seq++;
 185                 viochar->event.xSizeMinus1 =
 186                         offsetof(struct viocharlpevent, data) + len;
 187
 188                 memcpy(viochar->data, buf, len);
 189
 190                 hvrc = HvCallEvent_signalLpEvent(&viochar->event);
 191                 if (hvrc)
 192                         hvlog("\n\rerror sending event! return code %d\n\r",
 193                                 (int)hvrc);
 194                 sent += len;
 195                 count -= len;
 196                 buf += len;
 197         }
 198
 199         vio_free_event_buffer(viomajorsubtype_chario, viochar);
 200 done:
 201         spin_unlock_irqrestore(&consolelock, flags);
 202         return sent;
 203 }
 204
 205 static struct hv_ops hvc_get_put_ops = {
 206         .get_chars = get_chars,
 207         .put_chars = put_chars,
 208 };
 209
 210 static int __devinit hvc_vio_probe(struct vio_dev *vdev,
 211                         const struct vio_device_id *id)
 212 {
 213         struct hvc_struct *hp;
 214         struct port_info *pi;
 215
 216         /* probed with invalid parameters. */
 217         if (!vdev || !id)
 218                 return -EPERM;
 219
 220         if (vdev->unit_address >= VTTY_PORTS)
 221                 return -ENODEV;
 222
 223         pi = &port_info[vdev->unit_address];
 224
 225         hp = hvc_alloc(vdev->unit_address, vdev->irq, &hvc_get_put_ops,
 226                         VIOCHAR_MAX_DATA);
 227         if (IS_ERR(hp))
 228                 return PTR_ERR(hp);
 229         pi->hp = hp;
 230         dev_set_drvdata(&vdev->dev, pi);
 231
 232         return 0;
 233 }
 234
 235 static int __devexit hvc_vio_remove(struct vio_dev *vdev)
 236 {
 237         struct port_info *pi = dev_get_drvdata(&vdev->dev);
 238         struct hvc_struct *hp = pi->hp;
 239
 240         return hvc_remove(hp);
 241 }
 242
 243 static struct vio_driver hvc_vio_driver = {
 244         .id_table       = hvc_driver_table,
 245         .probe          = hvc_vio_probe,
 246         .remove         = hvc_vio_remove,
 247         .driver         = {
 248                 .name   = hvc_driver_name,
 249                 .owner  = THIS_MODULE,
 250         }
 251 };
 252
 253 static void hvc_open_event(struct HvLpEvent *event)
 254 {
 255         unsigned long flags;
 256         struct viocharlpevent *cevent = (struct viocharlpevent *)event;
 257         u8 port = cevent->virtual_device;
 258         struct port_info *pi;
 259         int reject = 0;
 260
 261         if (hvlpevent_is_ack(event)) {
 262                 if (port >= VTTY_PORTS)
 263                         return;
 264
 265                 spin_lock_irqsave(&consolelock, flags);
 266
 267                 pi = &port_info[port];
 268                 if (event->xRc == HvLpEvent_Rc_Good) {
 269                         pi->seq = pi->ack = 0;
 270                         /*
 271                          * This line allows connections from the primary
 272                          * partition but once one is connected from the
 273                          * primary partition nothing short of a reboot
 274                          * of linux will allow access from the hosting
 275                          * partition again without a required iSeries fix.
 276                          */
 277                         pi->lp = event->xTargetLp;
 278                 }
 279
 280                 spin_unlock_irqrestore(&consolelock, flags);
 281                 if (event->xRc != HvLpEvent_Rc_Good)
 282                         printk(KERN_WARNING
 283                                "hvc: handle_open_event: event->xRc == (%d).\n",
 284                                event->xRc);
 285
 286                 if (event->xCorrelationToken != 0) {
 287                         atomic_t *aptr= (atomic_t *)event->xCorrelationToken;
 288                         atomic_set(aptr, 1);
 289                 } else
 290                         printk(KERN_WARNING
 291                                "hvc: weird...got open ack without atomic\n");
 292                 return;
 293         }
 294
 295         /* This had better require an ack, otherwise complain */
 296         if (!hvlpevent_need_ack(event)) {
 297                 printk(KERN_WARNING "hvc: viocharopen without ack bit!\n");
 298                 return;
 299         }
 300
 301         spin_lock_irqsave(&consolelock, flags);
 302
 303         /* Make sure this is a good virtual tty */
 304         if (port >= VTTY_PORTS) {
 305                 event->xRc = HvLpEvent_Rc_SubtypeError;
 306                 cevent->subtype_result_code = viorc_openRejected;
 307                 /*
 308                  * Flag state here since we can't printk while holding
 309                  * the consolelock spinlock.
 310                  */
 311                 reject = 1;
 312         } else {
 313                 pi = &port_info[port];
 314                 if ((pi->lp != HvLpIndexInvalid) &&
 315                                 (pi->lp != event->xSourceLp)) {
 316                         /*
 317                          * If this is tty is already connected to a different
 318                          * partition, fail.
 319                          */
 320                         event->xRc = HvLpEvent_Rc_SubtypeError;
 321                         cevent->subtype_result_code = viorc_openRejected;
 322                         reject = 2;
 323                 } else {
 324                         pi->lp = event->xSourceLp;
 325                         event->xRc = HvLpEvent_Rc_Good;
 326                         cevent->subtype_result_code = viorc_good;
 327                         pi->seq = pi->ack = 0;
 328                 }
 329         }
 330
 331         spin_unlock_irqrestore(&consolelock, flags);
 332
 333         if (reject == 1)
 334                 printk(KERN_WARNING "hvc: open rejected: bad virtual tty.\n");
 335         else if (reject == 2)
 336                 printk(KERN_WARNING "hvc: open rejected: console in exclusive "
 337                                 "use by another partition.\n");
 338
 339         /* Return the acknowledgement */
 340         HvCallEvent_ackLpEvent(event);
 341 }
 342
 343 /*
 344  * Handle a close charLpEvent.  This should ONLY be an Interrupt because the
 345  * virtual console should never actually issue a close event to the hypervisor
 346  * because the virtual console never goes away.  A close event coming from the
 347  * hypervisor simply means that there are no client consoles connected to the
 348  * virtual console.
 349  */
 350 static void hvc_close_event(struct HvLpEvent *event)
 351 {
 352         unsigned long flags;
 353         struct viocharlpevent *cevent = (struct viocharlpevent *)event;
 354         u8 port = cevent->virtual_device;
 355
 356         if (!hvlpevent_is_int(event)) {
 357                 printk(KERN_WARNING
 358                         "hvc: got unexpected close acknowlegement\n");
 359                 return;
 360         }
 361
 362         if (port >= VTTY_PORTS) {
 363                 printk(KERN_WARNING
 364                         "hvc: close message from invalid virtual device.\n");
 365                 return;
 366         }
 367
 368         /* For closes, just mark the console partition invalid */
 369         spin_lock_irqsave(&consolelock, flags);
 370
 371         if (port_info[port].lp == event->xSourceLp)
 372                 port_info[port].lp = HvLpIndexInvalid;
 373
 374         spin_unlock_irqrestore(&consolelock, flags);
 375 }
 376
 377 static void hvc_data_event(struct HvLpEvent *event)
 378 {
 379         unsigned long flags;
 380         struct viocharlpevent *cevent = (struct viocharlpevent *)event;
 381         struct port_info *pi;
 382         int n;
 383         u8 port = cevent->virtual_device;
 384
 385         if (port >= VTTY_PORTS) {
 386                 printk(KERN_WARNING "hvc: data on invalid virtual device %d\n",
 387                                 port);
 388                 return;
 389         }
 390         if (cevent->len == 0)
 391                 return;
 392
 393         /*
 394          * Change 05/01/2003 - Ryan Arnold: If a partition other than
 395          * the current exclusive partition tries to send us data
 396          * events then just drop them on the floor because we don't
 397          * want his stinking data.  He isn't authorized to receive
 398          * data because he wasn't the first one to get the console,
 399          * therefore he shouldn't be allowed to send data either.
 400          * This will work without an iSeries fix.
 401          */
 402         pi = &port_info[port];
 403         if (pi->lp != event->xSourceLp)
 404                 return;
 405
 406         spin_lock_irqsave(&consolelock, flags);
 407
 408         n = IN_BUF_SIZE - pi->in_end;
 409         if (n > cevent->len)
 410                 n = cevent->len;
 411         if (n > 0) {
 412                 memcpy(&pi->in_buf[pi->in_end], cevent->data, n);
 413                 pi->in_end += n;
 414         }
 415         spin_unlock_irqrestore(&consolelock, flags);
 416         if (n == 0)
 417                 printk(KERN_WARNING "hvc: input buffer overflow\n");
 418 }
 419
 420 static void hvc_ack_event(struct HvLpEvent *event)
 421 {
 422         struct viocharlpevent *cevent = (struct viocharlpevent *)event;
 423         unsigned long flags;
 424         u8 port = cevent->virtual_device;
 425
 426         if (port >= VTTY_PORTS) {
 427                 printk(KERN_WARNING "hvc: data on invalid virtual device\n");
 428                 return;
 429         }
 430
 431         spin_lock_irqsave(&consolelock, flags);
 432         port_info[port].ack = event->xCorrelationToken;
 433         spin_unlock_irqrestore(&consolelock, flags);
 434 }
 435
 436 static void hvc_config_event(struct HvLpEvent *event)
 437 {
 438         struct viocharlpevent *cevent = (struct viocharlpevent *)event;
 439
 440         if (cevent->data[0] == 0x01)
 441                 printk(KERN_INFO "hvc: window resized to %d: %d: %d: %d\n",
 442                        cevent->data[1], cevent->data[2],
 443                        cevent->data[3], cevent->data[4]);
 444         else
 445                 printk(KERN_WARNING "hvc: unknown config event\n");
 446 }
 447
 448 static void hvc_handle_event(struct HvLpEvent *event)
 449 {
 450         int charminor;
 451
 452         if (event == NULL)
 453                 return;
 454
 455         charminor = event->xSubtype & VIOMINOR_SUBTYPE_MASK;
 456         switch (charminor) {
 457         case viocharopen:
 458                 hvc_open_event(event);
 459                 break;
 460         case viocharclose:
 461                 hvc_close_event(event);
 462                 break;
 463         case viochardata:
 464                 hvc_data_event(event);
 465                 break;
 466         case viocharack:
 467                 hvc_ack_event(event);
 468                 break;
 469         case viocharconfig:
 470                 hvc_config_event(event);
 471                 break;
 472         default:
 473                 if (hvlpevent_is_int(event) && hvlpevent_need_ack(event)) {
 474                         event->xRc = HvLpEvent_Rc_InvalidSubtype;
 475                         HvCallEvent_ackLpEvent(event);
 476                 }
 477         }
 478 }
 479
 480 static int send_open(HvLpIndex remoteLp, void *sem)
 481 {
 482         return HvCallEvent_signalLpEventFast(remoteLp,
 483                         HvLpEvent_Type_VirtualIo,
 484                         viomajorsubtype_chario | viocharopen,
 485                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
 486                         viopath_sourceinst(remoteLp),
 487                         viopath_targetinst(remoteLp),
 488                         (u64)(unsigned long)sem, VIOVERSION << 16,
 489                         0, 0, 0, 0);
 490 }
 491
 492 static int hvc_vio_init(void)
 493 {
 494         atomic_t wait_flag;
 495         int rc;
 496
 497         if (!firmware_has_feature(FW_FEATURE_ISERIES))
 498                 return -EIO;
 499
 500         /* +2 for fudge */
 501         rc = viopath_open(HvLpConfig_getPrimaryLpIndex(),
 502                         viomajorsubtype_chario, VIOCHAR_WINDOW + 2);
 503         if (rc)
 504                 printk(KERN_WARNING "hvc: error opening to primary %d\n", rc);
 505
 506         if (viopath_hostLp == HvLpIndexInvalid)
 507                 vio_set_hostlp();
 508
 509         /*
 510          * And if the primary is not the same as the hosting LP, open to the
 511          * hosting lp
 512          */
 513         if ((viopath_hostLp != HvLpIndexInvalid) &&
 514             (viopath_hostLp != HvLpConfig_getPrimaryLpIndex())) {
 515                 printk(KERN_INFO "hvc: open path to hosting (%d)\n",
 516                                 viopath_hostLp);
 517                 rc = viopath_open(viopath_hostLp, viomajorsubtype_chario,
 518                                 VIOCHAR_WINDOW + 2);    /* +2 for fudge */
 519                 if (rc)
 520                         printk(KERN_WARNING
 521                                 "error opening to partition %d: %d\n",
 522                                 viopath_hostLp, rc);
 523         }
 524
 525         if (vio_setHandler(viomajorsubtype_chario, hvc_handle_event) < 0)
 526                 printk(KERN_WARNING
 527                         "hvc: error seting handler for console events!\n");
 528
 529         /*
 530          * First, try to open the console to the hosting lp.
 531          * Wait on a semaphore for the response.
 532          */
 533         atomic_set(&wait_flag, 0);
 534         if ((viopath_isactive(viopath_hostLp)) &&
 535             (send_open(viopath_hostLp, &wait_flag) == 0)) {
 536                 printk(KERN_INFO "hvc: hosting partition %d\n", viopath_hostLp);
 537                 while (atomic_read(&wait_flag) == 0)
 538                         mb();
 539                 atomic_set(&wait_flag, 0);
 540         }
 541
 542         /*
 543          * If we don't have an active console, try the primary
 544          */
 545         if ((!viopath_isactive(port_info[0].lp)) &&
 546             (viopath_isactive(HvLpConfig_getPrimaryLpIndex())) &&
 547             (send_open(HvLpConfig_getPrimaryLpIndex(), &wait_flag) == 0)) {
 548                 printk(KERN_INFO "hvc: opening console to primary partition\n");
 549                 while (atomic_read(&wait_flag) == 0)
 550                         mb();
 551         }
 552
 553         /* Register as a vio device to receive callbacks */
 554         rc = vio_register_driver(&hvc_vio_driver);
 555
 556         return rc;
 557 }
 558 module_init(hvc_vio_init); /* after drivers/char/hvc_console.c */
 559
 560 static void hvc_vio_exit(void)
 561 {
 562         vio_unregister_driver(&hvc_vio_driver);
 563 }
 564 module_exit(hvc_vio_exit);
 565
 566 /* the device tree order defines our numbering */
 567 static int hvc_find_vtys(void)
 568 {
 569         struct device_node *vty;
 570         int num_found = 0;
 571
 572         for (vty = of_find_node_by_name(NULL, "vty"); vty != NULL;
 573                         vty = of_find_node_by_name(vty, "vty")) {
 574                 const uint32_t *vtermno;
 575
 576                 /* We have statically defined space for only a certain number
 577                  * of console adapters.
 578                  */
 579                 if ((num_found >= MAX_NR_HVC_CONSOLES) ||
 580                                 (num_found >= VTTY_PORTS))
 581                         break;
 582
 583                 vtermno = get_property(vty, "reg", NULL);
 584                 if (!vtermno)
 585                         continue;
 586
 587                 if (!device_is_compatible(vty, "IBM,iSeries-vty"))
 588                         continue;
 589
 590                 if (num_found == 0)
 591                         add_preferred_console("hvc", 0, NULL);
 592                 hvc_instantiate(*vtermno, num_found, &hvc_get_put_ops);
 593                 ++num_found;
 594         }
 595
 596         return num_found;
 597 }
 598 console_initcall(hvc_find_vtys);