kernel/drivers/scsi/isci/remote_node_context.c

   1 /*
   2  * This file is provided under a dual BSD/GPLv2 license.  When using or
   3  * redistributing this file, you may do so under either license.
   4  *
   5  * GPL LICENSE SUMMARY
   6  *
   7  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of version 2 of the GNU General Public License as
  11  * published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * 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., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  21  * The full GNU General Public License is included in this distribution
  22  * in the file called LICENSE.GPL.
  23  *
  24  * BSD LICENSE
  25  *
  26  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
  27  * All rights reserved.
  28  *
  29  * Redistribution and use in source and binary forms, with or without
  30  * modification, are permitted provided that the following conditions
  31  * are met:
  32  *
  33  *   * Redistributions of source code must retain the above copyright
  34  *     notice, this list of conditions and the following disclaimer.
  35  *   * Redistributions in binary form must reproduce the above copyright
  36  *     notice, this list of conditions and the following disclaimer in
  37  *     the documentation and/or other materials provided with the
  38  *     distribution.
  39  *   * Neither the name of Intel Corporation nor the names of its
  40  *     contributors may be used to endorse or promote products derived
  41  *     from this software without specific prior written permission.
  42  *
  43  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  44  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  45  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  46  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  47  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  48  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  49  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  50  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  51  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  52  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  53  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  54  */
  55 #include <scsi/sas_ata.h>
  56 #include "host.h"
  57 #include "isci.h"
  58 #include "remote_device.h"
  59 #include "remote_node_context.h"
  60 #include "scu_event_codes.h"
  61 #include "scu_task_context.h"
  62
  63 #undef C
  64 #define C(a) (#a)
  65 const char *rnc_state_name(enum scis_sds_remote_node_context_states state)
  66 {
  67         static const char * const strings[] = RNC_STATES;
  68
  69         return strings[state];
  70 }
  71 #undef C
  72
  73 /**
  74  *
  75  * @sci_rnc: The state of the remote node context object to check.
  76  *
  77  * This method will return true if the remote node context is in a READY state
  78  * otherwise it will return false bool true if the remote node context is in
  79  * the ready state. false if the remote node context is not in the ready state.
  80  */
  81 bool sci_remote_node_context_is_ready(
  82         struct sci_remote_node_context *sci_rnc)
  83 {
  84         u32 current_state = sci_rnc->sm.current_state_id;
  85
  86         if (current_state == SCI_RNC_READY) {
  87                 return true;
  88         }
  89
  90         return false;
  91 }
  92
  93 bool sci_remote_node_context_is_suspended(struct sci_remote_node_context *sci_rnc)
  94 {
  95         u32 current_state = sci_rnc->sm.current_state_id;
  96
  97         if (current_state == SCI_RNC_TX_RX_SUSPENDED)
  98                 return true;
  99         return false;
 100 }
 101
 102 static union scu_remote_node_context *sci_rnc_by_id(struct isci_host *ihost, u16 id)
 103 {
 104         if (id < ihost->remote_node_entries &&
 105             ihost->device_table[id])
 106                 return &ihost->remote_node_context_table[id];
 107
 108         return NULL;
 109 }
 110
 111 static void sci_remote_node_context_construct_buffer(struct sci_remote_node_context *sci_rnc)
 112 {
 113         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 114         struct domain_device *dev = idev->domain_dev;
 115         int rni = sci_rnc->remote_node_index;
 116         union scu_remote_node_context *rnc;
 117         struct isci_host *ihost;
 118         __le64 sas_addr;
 119
 120         ihost = idev->owning_port->owning_controller;
 121         rnc = sci_rnc_by_id(ihost, rni);
 122
 123         memset(rnc, 0, sizeof(union scu_remote_node_context)
 124                 * sci_remote_device_node_count(idev));
 125
 126         rnc->ssp.remote_node_index = rni;
 127         rnc->ssp.remote_node_port_width = idev->device_port_width;
 128         rnc->ssp.logical_port_index = idev->owning_port->physical_port_index;
 129
 130         /* sas address is __be64, context ram format is __le64 */
 131         sas_addr = cpu_to_le64(SAS_ADDR(dev->sas_addr));
 132         rnc->ssp.remote_sas_address_hi = upper_32_bits(sas_addr);
 133         rnc->ssp.remote_sas_address_lo = lower_32_bits(sas_addr);
 134
 135         rnc->ssp.nexus_loss_timer_enable = true;
 136         rnc->ssp.check_bit               = false;
 137         rnc->ssp.is_valid                = false;
 138         rnc->ssp.is_remote_node_context  = true;
 139         rnc->ssp.function_number         = 0;
 140
 141         rnc->ssp.arbitration_wait_time = 0;
 142
 143         if (dev_is_sata(dev)) {
 144                 rnc->ssp.connection_occupancy_timeout =
 145                         ihost->user_parameters.stp_max_occupancy_timeout;
 146                 rnc->ssp.connection_inactivity_timeout =
 147                         ihost->user_parameters.stp_inactivity_timeout;
 148         } else {
 149                 rnc->ssp.connection_occupancy_timeout  =
 150                         ihost->user_parameters.ssp_max_occupancy_timeout;
 151                 rnc->ssp.connection_inactivity_timeout =
 152                         ihost->user_parameters.ssp_inactivity_timeout;
 153         }
 154
 155         rnc->ssp.initial_arbitration_wait_time = 0;
 156
 157         /* Open Address Frame Parameters */
 158         rnc->ssp.oaf_connection_rate = idev->connection_rate;
 159         rnc->ssp.oaf_features = 0;
 160         rnc->ssp.oaf_source_zone_group = 0;
 161         rnc->ssp.oaf_more_compatibility_features = 0;
 162 }
 163 /**
 164  *
 165  * @sci_rnc:
 166  * @callback:
 167  * @callback_parameter:
 168  *
 169  * This method will setup the remote node context object so it will transition
 170  * to its ready state.  If the remote node context is already setup to
 171  * transition to its final state then this function does nothing. none
 172  */
 173 static void sci_remote_node_context_setup_to_resume(
 174         struct sci_remote_node_context *sci_rnc,
 175         scics_sds_remote_node_context_callback callback,
 176         void *callback_parameter,
 177         enum sci_remote_node_context_destination_state dest_param)
 178 {
 179         if (sci_rnc->destination_state != RNC_DEST_FINAL) {
 180                 sci_rnc->destination_state = dest_param;
 181                 if (callback != NULL) {
 182                         sci_rnc->user_callback = callback;
 183                         sci_rnc->user_cookie   = callback_parameter;
 184                 }
 185         }
 186 }
 187
 188 static void sci_remote_node_context_setup_to_destroy(
 189         struct sci_remote_node_context *sci_rnc,
 190         scics_sds_remote_node_context_callback callback,
 191         void *callback_parameter)
 192 {
 193         struct isci_host *ihost = idev_to_ihost(rnc_to_dev(sci_rnc));
 194
 195         sci_rnc->destination_state = RNC_DEST_FINAL;
 196         sci_rnc->user_callback     = callback;
 197         sci_rnc->user_cookie       = callback_parameter;
 198
 199         wake_up(&ihost->eventq);
 200 }
 201
 202 /**
 203  *
 204  *
 205  * This method just calls the user callback function and then resets the
 206  * callback.
 207  */
 208 static void sci_remote_node_context_notify_user(
 209         struct sci_remote_node_context *rnc)
 210 {
 211         if (rnc->user_callback != NULL) {
 212                 (*rnc->user_callback)(rnc->user_cookie);
 213
 214                 rnc->user_callback = NULL;
 215                 rnc->user_cookie = NULL;
 216         }
 217 }
 218
 219 static void sci_remote_node_context_continue_state_transitions(struct sci_remote_node_context *rnc)
 220 {
 221         switch (rnc->destination_state) {
 222         case RNC_DEST_READY:
 223         case RNC_DEST_SUSPENDED_RESUME:
 224                 rnc->destination_state = RNC_DEST_READY;
 225                 /* Fall through... */
 226         case RNC_DEST_FINAL:
 227                 sci_remote_node_context_resume(rnc, rnc->user_callback,
 228                                                rnc->user_cookie);
 229                 break;
 230         default:
 231                 rnc->destination_state = RNC_DEST_UNSPECIFIED;
 232                 break;
 233         }
 234 }
 235
 236 static void sci_remote_node_context_validate_context_buffer(struct sci_remote_node_context *sci_rnc)
 237 {
 238         union scu_remote_node_context *rnc_buffer;
 239         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 240         struct domain_device *dev = idev->domain_dev;
 241         struct isci_host *ihost = idev->owning_port->owning_controller;
 242
 243         rnc_buffer = sci_rnc_by_id(ihost, sci_rnc->remote_node_index);
 244
 245         rnc_buffer->ssp.is_valid = true;
 246
 247         if (dev_is_sata(dev) && dev->parent) {
 248                 sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_96);
 249         } else {
 250                 sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_32);
 251
 252                 if (!dev->parent)
 253                         sci_port_setup_transports(idev->owning_port,
 254                                                   sci_rnc->remote_node_index);
 255         }
 256 }
 257
 258 static void sci_remote_node_context_invalidate_context_buffer(struct sci_remote_node_context *sci_rnc)
 259 {
 260         union scu_remote_node_context *rnc_buffer;
 261         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 262         struct isci_host *ihost = idev->owning_port->owning_controller;
 263
 264         rnc_buffer = sci_rnc_by_id(ihost, sci_rnc->remote_node_index);
 265
 266         rnc_buffer->ssp.is_valid = false;
 267
 268         sci_remote_device_post_request(rnc_to_dev(sci_rnc),
 269                                        SCU_CONTEXT_COMMAND_POST_RNC_INVALIDATE);
 270 }
 271
 272 static void sci_remote_node_context_initial_state_enter(struct sci_base_state_machine *sm)
 273 {
 274         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 275         struct isci_remote_device *idev = rnc_to_dev(rnc);
 276         struct isci_host *ihost = idev->owning_port->owning_controller;
 277
 278         /* Check to see if we have gotten back to the initial state because
 279          * someone requested to destroy the remote node context object.
 280          */
 281         if (sm->previous_state_id == SCI_RNC_INVALIDATING) {
 282                 rnc->destination_state = RNC_DEST_UNSPECIFIED;
 283                 sci_remote_node_context_notify_user(rnc);
 284
 285                 smp_wmb();
 286                 wake_up(&ihost->eventq);
 287         }
 288 }
 289
 290 static void sci_remote_node_context_posting_state_enter(struct sci_base_state_machine *sm)
 291 {
 292         struct sci_remote_node_context *sci_rnc = container_of(sm, typeof(*sci_rnc), sm);
 293
 294         sci_remote_node_context_validate_context_buffer(sci_rnc);
 295 }
 296
 297 static void sci_remote_node_context_invalidating_state_enter(struct sci_base_state_machine *sm)
 298 {
 299         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 300
 301         /* Terminate all outstanding requests. */
 302         sci_remote_device_terminate_requests(rnc_to_dev(rnc));
 303         sci_remote_node_context_invalidate_context_buffer(rnc);
 304 }
 305
 306 static void sci_remote_node_context_resuming_state_enter(struct sci_base_state_machine *sm)
 307 {
 308         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 309         struct isci_remote_device *idev;
 310         struct domain_device *dev;
 311
 312         idev = rnc_to_dev(rnc);
 313         dev = idev->domain_dev;
 314
 315         /*
 316          * For direct attached SATA devices we need to clear the TLCR
 317          * NCQ to TCi tag mapping on the phy and in cases where we
 318          * resume because of a target reset we also need to update
 319          * the STPTLDARNI register with the RNi of the device
 320          */
 321         if (dev_is_sata(dev) && !dev->parent)
 322                 sci_port_setup_transports(idev->owning_port, rnc->remote_node_index);
 323
 324         sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_RESUME);
 325 }
 326
 327 static void sci_remote_node_context_ready_state_enter(struct sci_base_state_machine *sm)
 328 {
 329         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 330         enum sci_remote_node_context_destination_state dest_select;
 331         int tell_user = 1;
 332
 333         dest_select = rnc->destination_state;
 334         rnc->destination_state = RNC_DEST_UNSPECIFIED;
 335
 336         if ((dest_select == RNC_DEST_SUSPENDED) ||
 337             (dest_select == RNC_DEST_SUSPENDED_RESUME)) {
 338                 sci_remote_node_context_suspend(
 339                         rnc, rnc->suspend_reason,
 340                         SCI_SOFTWARE_SUSPEND_EXPECTED_EVENT);
 341
 342                 if (dest_select == RNC_DEST_SUSPENDED_RESUME)
 343                         tell_user = 0;  /* Wait until ready again. */
 344         }
 345         if (tell_user)
 346                 sci_remote_node_context_notify_user(rnc);
 347 }
 348
 349 static void sci_remote_node_context_tx_suspended_state_enter(struct sci_base_state_machine *sm)
 350 {
 351         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 352
 353         sci_remote_node_context_continue_state_transitions(rnc);
 354 }
 355
 356 static void sci_remote_node_context_tx_rx_suspended_state_enter(struct sci_base_state_machine *sm)
 357 {
 358         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 359         struct isci_remote_device *idev = rnc_to_dev(rnc);
 360         struct isci_host *ihost = idev->owning_port->owning_controller;
 361         u32 new_count = rnc->suspend_count + 1;
 362
 363         if (new_count == 0)
 364                 rnc->suspend_count = 1;
 365         else
 366                 rnc->suspend_count = new_count;
 367         smp_wmb();
 368
 369         /* Terminate outstanding requests pending abort. */
 370         sci_remote_device_abort_requests_pending_abort(idev);
 371
 372         wake_up(&ihost->eventq);
 373         sci_remote_node_context_continue_state_transitions(rnc);
 374 }
 375
 376 static void sci_remote_node_context_await_suspend_state_exit(
 377         struct sci_base_state_machine *sm)
 378 {
 379         struct sci_remote_node_context *rnc
 380                 = container_of(sm, typeof(*rnc), sm);
 381         struct isci_remote_device *idev = rnc_to_dev(rnc);
 382
 383         if (dev_is_sata(idev->domain_dev))
 384                 isci_dev_set_hang_detection_timeout(idev, 0);
 385 }
 386
 387 static const struct sci_base_state sci_remote_node_context_state_table[] = {
 388         [SCI_RNC_INITIAL] = {
 389                 .enter_state = sci_remote_node_context_initial_state_enter,
 390         },
 391         [SCI_RNC_POSTING] = {
 392                 .enter_state = sci_remote_node_context_posting_state_enter,
 393         },
 394         [SCI_RNC_INVALIDATING] = {
 395                 .enter_state = sci_remote_node_context_invalidating_state_enter,
 396         },
 397         [SCI_RNC_RESUMING] = {
 398                 .enter_state = sci_remote_node_context_resuming_state_enter,
 399         },
 400         [SCI_RNC_READY] = {
 401                 .enter_state = sci_remote_node_context_ready_state_enter,
 402         },
 403         [SCI_RNC_TX_SUSPENDED] = {
 404                 .enter_state = sci_remote_node_context_tx_suspended_state_enter,
 405         },
 406         [SCI_RNC_TX_RX_SUSPENDED] = {
 407                 .enter_state = sci_remote_node_context_tx_rx_suspended_state_enter,
 408         },
 409         [SCI_RNC_AWAIT_SUSPENSION] = {
 410                 .exit_state = sci_remote_node_context_await_suspend_state_exit,
 411         },
 412 };
 413
 414 void sci_remote_node_context_construct(struct sci_remote_node_context *rnc,
 415                                             u16 remote_node_index)
 416 {
 417         memset(rnc, 0, sizeof(struct sci_remote_node_context));
 418
 419         rnc->remote_node_index = remote_node_index;
 420         rnc->destination_state = RNC_DEST_UNSPECIFIED;
 421
 422         sci_init_sm(&rnc->sm, sci_remote_node_context_state_table, SCI_RNC_INITIAL);
 423 }
 424
 425 enum sci_status sci_remote_node_context_event_handler(struct sci_remote_node_context *sci_rnc,
 426                                                            u32 event_code)
 427 {
 428         enum scis_sds_remote_node_context_states state;
 429         u32 next_state;
 430
 431         state = sci_rnc->sm.current_state_id;
 432         switch (state) {
 433         case SCI_RNC_POSTING:
 434                 switch (scu_get_event_code(event_code)) {
 435                 case SCU_EVENT_POST_RNC_COMPLETE:
 436                         sci_change_state(&sci_rnc->sm, SCI_RNC_READY);
 437                         break;
 438                 default:
 439                         goto out;
 440                 }
 441                 break;
 442         case SCI_RNC_INVALIDATING:
 443                 if (scu_get_event_code(event_code) == SCU_EVENT_POST_RNC_INVALIDATE_COMPLETE) {
 444                         if (sci_rnc->destination_state == RNC_DEST_FINAL)
 445                                 next_state = SCI_RNC_INITIAL;
 446                         else
 447                                 next_state = SCI_RNC_POSTING;
 448                         sci_change_state(&sci_rnc->sm, next_state);
 449                 } else {
 450                         switch (scu_get_event_type(event_code)) {
 451                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
 452                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
 453                                 /* We really dont care if the hardware is going to suspend
 454                                  * the device since it's being invalidated anyway */
 455                                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 456                                         "%s: SCIC Remote Node Context 0x%p was "
 457                                         "suspeneded by hardware while being "
 458                                         "invalidated.\n", __func__, sci_rnc);
 459                                 break;
 460                         default:
 461                                 goto out;
 462                         }
 463                 }
 464                 break;
 465         case SCI_RNC_RESUMING:
 466                 if (scu_get_event_code(event_code) == SCU_EVENT_POST_RCN_RELEASE) {
 467                         sci_change_state(&sci_rnc->sm, SCI_RNC_READY);
 468                 } else {
 469                         switch (scu_get_event_type(event_code)) {
 470                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
 471                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
 472                                 /* We really dont care if the hardware is going to suspend
 473                                  * the device since it's being resumed anyway */
 474                                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 475                                         "%s: SCIC Remote Node Context 0x%p was "
 476                                         "suspeneded by hardware while being resumed.\n",
 477                                         __func__, sci_rnc);
 478                                 break;
 479                         default:
 480                                 goto out;
 481                         }
 482                 }
 483                 break;
 484         case SCI_RNC_READY:
 485                 switch (scu_get_event_type(event_code)) {
 486                 case SCU_EVENT_TL_RNC_SUSPEND_TX:
 487                         sci_change_state(&sci_rnc->sm, SCI_RNC_TX_SUSPENDED);
 488                         sci_rnc->suspend_type = scu_get_event_type(event_code);
 489                         break;
 490                 case SCU_EVENT_TL_RNC_SUSPEND_TX_RX:
 491                         sci_change_state(&sci_rnc->sm, SCI_RNC_TX_RX_SUSPENDED);
 492                         sci_rnc->suspend_type = scu_get_event_type(event_code);
 493                         break;
 494                 default:
 495                         goto out;
 496                 }
 497                 break;
 498         case SCI_RNC_AWAIT_SUSPENSION:
 499                 switch (scu_get_event_type(event_code)) {
 500                 case SCU_EVENT_TL_RNC_SUSPEND_TX:
 501                         next_state = SCI_RNC_TX_SUSPENDED;
 502                         break;
 503                 case SCU_EVENT_TL_RNC_SUSPEND_TX_RX:
 504                         next_state = SCI_RNC_TX_RX_SUSPENDED;
 505                         break;
 506                 default:
 507                         goto out;
 508                 }
 509                 if (sci_rnc->suspend_type == scu_get_event_type(event_code))
 510                         sci_change_state(&sci_rnc->sm, next_state);
 511                 break;
 512         default:
 513                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 514                          "%s: invalid state: %s\n", __func__,
 515                          rnc_state_name(state));
 516                 return SCI_FAILURE_INVALID_STATE;
 517         }
 518         return SCI_SUCCESS;
 519
 520  out:
 521         dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 522                  "%s: code: %#x state: %s\n", __func__, event_code,
 523                  rnc_state_name(state));
 524         return SCI_FAILURE;
 525
 526 }
 527
 528 enum sci_status sci_remote_node_context_destruct(struct sci_remote_node_context *sci_rnc,
 529                                                       scics_sds_remote_node_context_callback cb_fn,
 530                                                       void *cb_p)
 531 {
 532         enum scis_sds_remote_node_context_states state;
 533
 534         state = sci_rnc->sm.current_state_id;
 535         switch (state) {
 536         case SCI_RNC_INVALIDATING:
 537                 sci_remote_node_context_setup_to_destroy(sci_rnc, cb_fn, cb_p);
 538                 return SCI_SUCCESS;
 539         case SCI_RNC_POSTING:
 540         case SCI_RNC_RESUMING:
 541         case SCI_RNC_READY:
 542         case SCI_RNC_TX_SUSPENDED:
 543         case SCI_RNC_TX_RX_SUSPENDED:
 544                 sci_remote_node_context_setup_to_destroy(sci_rnc, cb_fn, cb_p);
 545                 sci_change_state(&sci_rnc->sm, SCI_RNC_INVALIDATING);
 546                 return SCI_SUCCESS;
 547         case SCI_RNC_AWAIT_SUSPENSION:
 548                 sci_remote_node_context_setup_to_destroy(sci_rnc, cb_fn, cb_p);
 549                 return SCI_SUCCESS;
 550         case SCI_RNC_INITIAL:
 551                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 552                          "%s: invalid state: %s\n", __func__,
 553                          rnc_state_name(state));
 554                 /* We have decided that the destruct request on the remote node context
 555                  * can not fail since it is either in the initial/destroyed state or is
 556                  * can be destroyed.
 557                  */
 558                 return SCI_SUCCESS;
 559         default:
 560                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 561                          "%s: invalid state %s\n", __func__,
 562                          rnc_state_name(state));
 563                 return SCI_FAILURE_INVALID_STATE;
 564         }
 565 }
 566
 567 enum sci_status sci_remote_node_context_suspend(
 568                         struct sci_remote_node_context *sci_rnc,
 569                         enum sci_remote_node_suspension_reasons suspend_reason,
 570                         u32 suspend_type)
 571 {
 572         enum scis_sds_remote_node_context_states state
 573                 = sci_rnc->sm.current_state_id;
 574         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 575         enum sci_status status = SCI_FAILURE_INVALID_STATE;
 576         enum sci_remote_node_context_destination_state dest_param =
 577                 RNC_DEST_UNSPECIFIED;
 578
 579         dev_dbg(scirdev_to_dev(idev),
 580                 "%s: current state %s, current suspend_type %x dest state %d,"
 581                         " arg suspend_reason %d, arg suspend_type %x",
 582                 __func__, rnc_state_name(state), sci_rnc->suspend_type,
 583                 sci_rnc->destination_state, suspend_reason,
 584                 suspend_type);
 585
 586         /* Disable automatic state continuations if explicitly suspending. */
 587         if ((suspend_reason == SCI_HW_SUSPEND) ||
 588             (sci_rnc->destination_state == RNC_DEST_FINAL))
 589                 dest_param = sci_rnc->destination_state;
 590
 591         switch (state) {
 592         case SCI_RNC_READY:
 593                 break;
 594         case SCI_RNC_INVALIDATING:
 595                 if (sci_rnc->destination_state == RNC_DEST_FINAL) {
 596                         dev_warn(scirdev_to_dev(idev),
 597                                  "%s: already destroying %p\n",
 598                                  __func__, sci_rnc);
 599                         return SCI_FAILURE_INVALID_STATE;
 600                 }
 601                 /* Fall through and handle like SCI_RNC_POSTING */
 602         case SCI_RNC_RESUMING:
 603                 /* Fall through and handle like SCI_RNC_POSTING */
 604         case SCI_RNC_POSTING:
 605                 /* Set the destination state to AWAIT - this signals the
 606                  * entry into the SCI_RNC_READY state that a suspension
 607                  * needs to be done immediately.
 608                  */
 609                 if (sci_rnc->destination_state != RNC_DEST_FINAL)
 610                         sci_rnc->destination_state = RNC_DEST_SUSPENDED;
 611                 sci_rnc->suspend_type = suspend_type;
 612                 sci_rnc->suspend_reason = suspend_reason;
 613                 return SCI_SUCCESS;
 614
 615         case SCI_RNC_TX_SUSPENDED:
 616                 if (suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX)
 617                         status = SCI_SUCCESS;
 618                 break;
 619         case SCI_RNC_TX_RX_SUSPENDED:
 620                 if (suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX_RX)
 621                         status = SCI_SUCCESS;
 622                 break;
 623         case SCI_RNC_AWAIT_SUSPENSION:
 624                 if ((sci_rnc->suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX_RX)
 625                     || (suspend_type == sci_rnc->suspend_type))
 626                         return SCI_SUCCESS;
 627                 break;
 628         default:
 629                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 630                          "%s: invalid state %s\n", __func__,
 631                          rnc_state_name(state));
 632                 return SCI_FAILURE_INVALID_STATE;
 633         }
 634         sci_rnc->destination_state = dest_param;
 635         sci_rnc->suspend_type = suspend_type;
 636         sci_rnc->suspend_reason = suspend_reason;
 637
 638         if (status == SCI_SUCCESS) { /* Already in the destination state? */
 639                 struct isci_host *ihost = idev->owning_port->owning_controller;
 640
 641                 wake_up_all(&ihost->eventq); /* Let observers look. */
 642                 return SCI_SUCCESS;
 643         }
 644         if ((suspend_reason == SCI_SW_SUSPEND_NORMAL) ||
 645             (suspend_reason == SCI_SW_SUSPEND_LINKHANG_DETECT)) {
 646
 647                 if (suspend_reason == SCI_SW_SUSPEND_LINKHANG_DETECT)
 648                         isci_dev_set_hang_detection_timeout(idev, 0x00000001);
 649
 650                 sci_remote_device_post_request(
 651                         idev, SCI_SOFTWARE_SUSPEND_CMD);
 652         }
 653         if (state != SCI_RNC_AWAIT_SUSPENSION)
 654                 sci_change_state(&sci_rnc->sm, SCI_RNC_AWAIT_SUSPENSION);
 655
 656         return SCI_SUCCESS;
 657 }
 658
 659 enum sci_status sci_remote_node_context_resume(struct sci_remote_node_context *sci_rnc,
 660                                                     scics_sds_remote_node_context_callback cb_fn,
 661                                                     void *cb_p)
 662 {
 663         enum scis_sds_remote_node_context_states state;
 664         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 665
 666         state = sci_rnc->sm.current_state_id;
 667         dev_dbg(scirdev_to_dev(idev),
 668                 "%s: state %s, cb_fn = %p, cb_p = %p; dest_state = %d; "
 669                         "dev resume path %s\n",
 670                 __func__, rnc_state_name(state), cb_fn, cb_p,
 671                 sci_rnc->destination_state,
 672                 test_bit(IDEV_ABORT_PATH_ACTIVE, &idev->flags)
 673                         ? "<abort active>" : "<normal>");
 674
 675         switch (state) {
 676         case SCI_RNC_INITIAL:
 677                 if (sci_rnc->remote_node_index == SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX)
 678                         return SCI_FAILURE_INVALID_STATE;
 679
 680                 sci_remote_node_context_setup_to_resume(sci_rnc, cb_fn, cb_p,
 681                                                         RNC_DEST_READY);
 682                 if (!test_bit(IDEV_ABORT_PATH_ACTIVE, &idev->flags)) {
 683                         sci_remote_node_context_construct_buffer(sci_rnc);
 684                         sci_change_state(&sci_rnc->sm, SCI_RNC_POSTING);
 685                 }
 686                 return SCI_SUCCESS;
 687
 688         case SCI_RNC_POSTING:
 689         case SCI_RNC_INVALIDATING:
 690         case SCI_RNC_RESUMING:
 691                 /* We are still waiting to post when a resume was
 692                  * requested.
 693                  */
 694                 switch (sci_rnc->destination_state) {
 695                 case RNC_DEST_SUSPENDED:
 696                 case RNC_DEST_SUSPENDED_RESUME:
 697                         /* Previously waiting to suspend after posting.
 698                          * Now continue onto resumption.
 699                          */
 700                         sci_remote_node_context_setup_to_resume(
 701                                 sci_rnc, cb_fn, cb_p,
 702                                 RNC_DEST_SUSPENDED_RESUME);
 703                         break;
 704                 default:
 705                         sci_remote_node_context_setup_to_resume(
 706                                 sci_rnc, cb_fn, cb_p,
 707                                 RNC_DEST_READY);
 708                         break;
 709                 }
 710                 return SCI_SUCCESS;
 711
 712         case SCI_RNC_TX_SUSPENDED:
 713         case SCI_RNC_TX_RX_SUSPENDED:
 714                 {
 715                         struct domain_device *dev = idev->domain_dev;
 716                         /* If this is an expander attached SATA device we must
 717                          * invalidate and repost the RNC since this is the only
 718                          * way to clear the TCi to NCQ tag mapping table for
 719                          * the RNi. All other device types we can just resume.
 720                          */
 721                         sci_remote_node_context_setup_to_resume(
 722                                 sci_rnc, cb_fn, cb_p, RNC_DEST_READY);
 723
 724                         if (!test_bit(IDEV_ABORT_PATH_ACTIVE, &idev->flags)) {
 725                                 if ((dev_is_sata(dev) && dev->parent) ||
 726                                     (sci_rnc->destination_state == RNC_DEST_FINAL))
 727                                         sci_change_state(&sci_rnc->sm,
 728                                                          SCI_RNC_INVALIDATING);
 729                                 else
 730                                         sci_change_state(&sci_rnc->sm,
 731                                                          SCI_RNC_RESUMING);
 732                         }
 733                 }
 734                 return SCI_SUCCESS;
 735
 736         case SCI_RNC_AWAIT_SUSPENSION:
 737                 sci_remote_node_context_setup_to_resume(
 738                         sci_rnc, cb_fn, cb_p, RNC_DEST_SUSPENDED_RESUME);
 739                 return SCI_SUCCESS;
 740         default:
 741                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 742                          "%s: invalid state %s\n", __func__,
 743                          rnc_state_name(state));
 744                 return SCI_FAILURE_INVALID_STATE;
 745         }
 746 }
 747
 748 enum sci_status sci_remote_node_context_start_io(struct sci_remote_node_context *sci_rnc,
 749                                                              struct isci_request *ireq)
 750 {
 751         enum scis_sds_remote_node_context_states state;
 752
 753         state = sci_rnc->sm.current_state_id;
 754
 755         switch (state) {
 756         case SCI_RNC_READY:
 757                 return SCI_SUCCESS;
 758         case SCI_RNC_TX_SUSPENDED:
 759         case SCI_RNC_TX_RX_SUSPENDED:
 760         case SCI_RNC_AWAIT_SUSPENSION:
 761                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 762                          "%s: invalid state %s\n", __func__,
 763                          rnc_state_name(state));
 764                 return SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED;
 765         default:
 766                 dev_dbg(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 767                         "%s: invalid state %s\n", __func__,
 768                         rnc_state_name(state));
 769                 return SCI_FAILURE_INVALID_STATE;
 770         }
 771 }
 772
 773 enum sci_status sci_remote_node_context_start_task(
 774         struct sci_remote_node_context *sci_rnc,
 775         struct isci_request *ireq,
 776         scics_sds_remote_node_context_callback cb_fn,
 777         void *cb_p)
 778 {
 779         enum sci_status status = sci_remote_node_context_resume(sci_rnc,
 780                                                                 cb_fn, cb_p);
 781         if (status != SCI_SUCCESS)
 782                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 783                         "%s: resume failed: %d\n", __func__, status);
 784         return status;
 785 }
 786
 787 int sci_remote_node_context_is_safe_to_abort(
 788         struct sci_remote_node_context *sci_rnc)
 789 {
 790         enum scis_sds_remote_node_context_states state;
 791
 792         state = sci_rnc->sm.current_state_id;
 793         switch (state) {
 794         case SCI_RNC_INVALIDATING:
 795         case SCI_RNC_TX_RX_SUSPENDED:
 796                 return 1;
 797         case SCI_RNC_POSTING:
 798         case SCI_RNC_RESUMING:
 799         case SCI_RNC_READY:
 800         case SCI_RNC_TX_SUSPENDED:
 801         case SCI_RNC_AWAIT_SUSPENSION:
 802         case SCI_RNC_INITIAL:
 803                 return 0;
 804         default:
 805                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 806                          "%s: invalid state %d\n", __func__, state);
 807                 return 0;
 808         }
 809 }