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
  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 static union scu_remote_node_context *sci_rnc_by_id(struct isci_host *ihost, u16 id)
  94 {
  95         if (id < ihost->remote_node_entries &&
  96             ihost->device_table[id])
  97                 return &ihost->remote_node_context_table[id];
  98
  99         return NULL;
 100 }
 101
 102 static void sci_remote_node_context_construct_buffer(struct sci_remote_node_context *sci_rnc)
 103 {
 104         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 105         struct domain_device *dev = idev->domain_dev;
 106         int rni = sci_rnc->remote_node_index;
 107         union scu_remote_node_context *rnc;
 108         struct isci_host *ihost;
 109         __le64 sas_addr;
 110
 111         ihost = idev->owning_port->owning_controller;
 112         rnc = sci_rnc_by_id(ihost, rni);
 113
 114         memset(rnc, 0, sizeof(union scu_remote_node_context)
 115                 * sci_remote_device_node_count(idev));
 116
 117         rnc->ssp.remote_node_index = rni;
 118         rnc->ssp.remote_node_port_width = idev->device_port_width;
 119         rnc->ssp.logical_port_index = idev->owning_port->physical_port_index;
 120
 121         /* sas address is __be64, context ram format is __le64 */
 122         sas_addr = cpu_to_le64(SAS_ADDR(dev->sas_addr));
 123         rnc->ssp.remote_sas_address_hi = upper_32_bits(sas_addr);
 124         rnc->ssp.remote_sas_address_lo = lower_32_bits(sas_addr);
 125
 126         rnc->ssp.nexus_loss_timer_enable = true;
 127         rnc->ssp.check_bit               = false;
 128         rnc->ssp.is_valid                = false;
 129         rnc->ssp.is_remote_node_context  = true;
 130         rnc->ssp.function_number         = 0;
 131
 132         rnc->ssp.arbitration_wait_time = 0;
 133
 134         if (dev_is_sata(dev)) {
 135                 rnc->ssp.connection_occupancy_timeout =
 136                         ihost->user_parameters.stp_max_occupancy_timeout;
 137                 rnc->ssp.connection_inactivity_timeout =
 138                         ihost->user_parameters.stp_inactivity_timeout;
 139         } else {
 140                 rnc->ssp.connection_occupancy_timeout  =
 141                         ihost->user_parameters.ssp_max_occupancy_timeout;
 142                 rnc->ssp.connection_inactivity_timeout =
 143                         ihost->user_parameters.ssp_inactivity_timeout;
 144         }
 145
 146         rnc->ssp.initial_arbitration_wait_time = 0;
 147
 148         /* Open Address Frame Parameters */
 149         rnc->ssp.oaf_connection_rate = idev->connection_rate;
 150         rnc->ssp.oaf_features = 0;
 151         rnc->ssp.oaf_source_zone_group = 0;
 152         rnc->ssp.oaf_more_compatibility_features = 0;
 153 }
 154
 155 /**
 156  *
 157  * @sci_rnc:
 158  * @callback:
 159  * @callback_parameter:
 160  *
 161  * This method will setup the remote node context object so it will transition
 162  * to its ready state.  If the remote node context is already setup to
 163  * transition to its final state then this function does nothing. none
 164  */
 165 static void sci_remote_node_context_setup_to_resume(
 166         struct sci_remote_node_context *sci_rnc,
 167         scics_sds_remote_node_context_callback callback,
 168         void *callback_parameter,
 169         enum sci_remote_node_context_destination_state dest_param)
 170 {
 171         if (sci_rnc->destination_state != RNC_DEST_FINAL) {
 172                 sci_rnc->destination_state = dest_param;
 173                 if (callback != NULL) {
 174                         sci_rnc->user_callback = callback;
 175                         sci_rnc->user_cookie   = callback_parameter;
 176                 }
 177         }
 178 }
 179
 180 static void sci_remote_node_context_setup_to_destroy(
 181         struct sci_remote_node_context *sci_rnc,
 182         scics_sds_remote_node_context_callback callback,
 183         void *callback_parameter)
 184 {
 185         sci_rnc->destination_state = RNC_DEST_FINAL;
 186         sci_rnc->user_callback     = callback;
 187         sci_rnc->user_cookie       = callback_parameter;
 188 }
 189
 190 /**
 191  *
 192  *
 193  * This method just calls the user callback function and then resets the
 194  * callback.
 195  */
 196 static void sci_remote_node_context_notify_user(
 197         struct sci_remote_node_context *rnc)
 198 {
 199         if (rnc->user_callback != NULL) {
 200                 (*rnc->user_callback)(rnc->user_cookie);
 201
 202                 rnc->user_callback = NULL;
 203                 rnc->user_cookie = NULL;
 204         }
 205 }
 206
 207 static void sci_remote_node_context_continue_state_transitions(struct sci_remote_node_context *rnc)
 208 {
 209         if ((rnc->destination_state == RNC_DEST_READY) ||
 210             (rnc->destination_state == RNC_DEST_SUSPENDED_RESUME)) {
 211                 rnc->destination_state = RNC_DEST_READY;
 212                 sci_remote_node_context_resume(rnc, rnc->user_callback,
 213                                                     rnc->user_cookie);
 214         } else
 215                 rnc->destination_state = RNC_DEST_UNSPECIFIED;
 216 }
 217
 218 static void sci_remote_node_context_validate_context_buffer(struct sci_remote_node_context *sci_rnc)
 219 {
 220         union scu_remote_node_context *rnc_buffer;
 221         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 222         struct domain_device *dev = idev->domain_dev;
 223         struct isci_host *ihost = idev->owning_port->owning_controller;
 224
 225         rnc_buffer = sci_rnc_by_id(ihost, sci_rnc->remote_node_index);
 226
 227         rnc_buffer->ssp.is_valid = true;
 228
 229         if (dev_is_sata(dev) && dev->parent) {
 230                 sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_96);
 231         } else {
 232                 sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_32);
 233
 234                 if (!dev->parent)
 235                         sci_port_setup_transports(idev->owning_port,
 236                                                   sci_rnc->remote_node_index);
 237         }
 238 }
 239
 240 static void sci_remote_node_context_invalidate_context_buffer(struct sci_remote_node_context *sci_rnc)
 241 {
 242         union scu_remote_node_context *rnc_buffer;
 243         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 244         struct isci_host *ihost = idev->owning_port->owning_controller;
 245
 246         rnc_buffer = sci_rnc_by_id(ihost, sci_rnc->remote_node_index);
 247
 248         rnc_buffer->ssp.is_valid = false;
 249
 250         sci_remote_device_post_request(rnc_to_dev(sci_rnc),
 251                                        SCU_CONTEXT_COMMAND_POST_RNC_INVALIDATE);
 252 }
 253
 254 static void sci_remote_node_context_initial_state_enter(struct sci_base_state_machine *sm)
 255 {
 256         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 257
 258         /* Check to see if we have gotten back to the initial state because
 259          * someone requested to destroy the remote node context object.
 260          */
 261         if (sm->previous_state_id == SCI_RNC_INVALIDATING) {
 262                 rnc->destination_state = RNC_DEST_UNSPECIFIED;
 263                 sci_remote_node_context_notify_user(rnc);
 264         }
 265 }
 266
 267 static void sci_remote_node_context_posting_state_enter(struct sci_base_state_machine *sm)
 268 {
 269         struct sci_remote_node_context *sci_rnc = container_of(sm, typeof(*sci_rnc), sm);
 270
 271         sci_remote_node_context_validate_context_buffer(sci_rnc);
 272 }
 273
 274 static void sci_remote_node_context_invalidating_state_enter(struct sci_base_state_machine *sm)
 275 {
 276         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 277
 278         /* Terminate all outstanding requests. */
 279         sci_remote_device_terminate_requests(rnc_to_dev(rnc));
 280         sci_remote_node_context_invalidate_context_buffer(rnc);
 281 }
 282
 283 static void sci_remote_node_context_resuming_state_enter(struct sci_base_state_machine *sm)
 284 {
 285         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 286         struct isci_remote_device *idev;
 287         struct domain_device *dev;
 288
 289         idev = rnc_to_dev(rnc);
 290         dev = idev->domain_dev;
 291
 292         /*
 293          * For direct attached SATA devices we need to clear the TLCR
 294          * NCQ to TCi tag mapping on the phy and in cases where we
 295          * resume because of a target reset we also need to update
 296          * the STPTLDARNI register with the RNi of the device
 297          */
 298         if (dev_is_sata(dev) && !dev->parent)
 299                 sci_port_setup_transports(idev->owning_port, rnc->remote_node_index);
 300
 301         sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_RESUME);
 302 }
 303
 304 static void sci_remote_node_context_ready_state_enter(struct sci_base_state_machine *sm)
 305 {
 306         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 307         enum sci_remote_node_context_destination_state dest_select;
 308         scics_sds_remote_node_context_callback usr_cb = rnc->user_callback;
 309         void *usr_param = rnc->user_cookie;
 310         int tell_user = 1;
 311
 312         dest_select = rnc->destination_state;
 313         rnc->destination_state = RNC_DEST_UNSPECIFIED;
 314
 315         if ((dest_select == RNC_DEST_SUSPENDED) ||
 316             (dest_select == RNC_DEST_SUSPENDED_RESUME)) {
 317                 sci_remote_node_context_suspend(
 318                         rnc, SCI_SOFTWARE_SUSPENSION,
 319                         SCI_SOFTWARE_SUSPEND_EXPECTED_EVENT, NULL, NULL);
 320
 321                 if (dest_select == RNC_DEST_SUSPENDED_RESUME) {
 322                         sci_remote_node_context_resume(rnc, usr_cb, usr_param);
 323                         tell_user = 0;  /* Wait until ready again. */
 324                 }
 325         }
 326         if (tell_user && rnc->user_callback)
 327                 sci_remote_node_context_notify_user(rnc);
 328 }
 329
 330 static void sci_remote_node_context_tx_suspended_state_enter(struct sci_base_state_machine *sm)
 331 {
 332         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 333
 334         sci_remote_node_context_continue_state_transitions(rnc);
 335 }
 336
 337 static void sci_remote_node_context_tx_rx_suspended_state_enter(struct sci_base_state_machine *sm)
 338 {
 339         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 340         struct isci_remote_device *idev = rnc_to_dev(rnc);
 341         struct isci_host *ihost = idev->owning_port->owning_controller;
 342
 343         /* Terminate outstanding requests pending abort. */
 344         sci_remote_device_abort_requests_pending_abort(idev);
 345
 346         wake_up(&ihost->eventq);
 347         sci_remote_node_context_continue_state_transitions(rnc);
 348 }
 349
 350 static void sci_remote_node_context_await_suspend_state_exit(
 351         struct sci_base_state_machine *sm)
 352 {
 353         struct sci_remote_node_context *rnc
 354                 = container_of(sm, typeof(*rnc), sm);
 355
 356         isci_dev_set_hang_detection_timeout(rnc_to_dev(rnc), 0);
 357 }
 358
 359 static const struct sci_base_state sci_remote_node_context_state_table[] = {
 360         [SCI_RNC_INITIAL] = {
 361                 .enter_state = sci_remote_node_context_initial_state_enter,
 362         },
 363         [SCI_RNC_POSTING] = {
 364                 .enter_state = sci_remote_node_context_posting_state_enter,
 365         },
 366         [SCI_RNC_INVALIDATING] = {
 367                 .enter_state = sci_remote_node_context_invalidating_state_enter,
 368         },
 369         [SCI_RNC_RESUMING] = {
 370                 .enter_state = sci_remote_node_context_resuming_state_enter,
 371         },
 372         [SCI_RNC_READY] = {
 373                 .enter_state = sci_remote_node_context_ready_state_enter,
 374         },
 375         [SCI_RNC_TX_SUSPENDED] = {
 376                 .enter_state = sci_remote_node_context_tx_suspended_state_enter,
 377         },
 378         [SCI_RNC_TX_RX_SUSPENDED] = {
 379                 .enter_state = sci_remote_node_context_tx_rx_suspended_state_enter,
 380         },
 381         [SCI_RNC_AWAIT_SUSPENSION] = {
 382                 .exit_state = sci_remote_node_context_await_suspend_state_exit,
 383         },
 384 };
 385
 386 void sci_remote_node_context_construct(struct sci_remote_node_context *rnc,
 387                                             u16 remote_node_index)
 388 {
 389         memset(rnc, 0, sizeof(struct sci_remote_node_context));
 390
 391         rnc->remote_node_index = remote_node_index;
 392         rnc->destination_state = RNC_DEST_UNSPECIFIED;
 393
 394         sci_init_sm(&rnc->sm, sci_remote_node_context_state_table, SCI_RNC_INITIAL);
 395 }
 396
 397 enum sci_status sci_remote_node_context_event_handler(struct sci_remote_node_context *sci_rnc,
 398                                                            u32 event_code)
 399 {
 400         enum scis_sds_remote_node_context_states state;
 401         u32 next_state;
 402
 403         state = sci_rnc->sm.current_state_id;
 404         switch (state) {
 405         case SCI_RNC_POSTING:
 406                 switch (scu_get_event_code(event_code)) {
 407                 case SCU_EVENT_POST_RNC_COMPLETE:
 408                         sci_change_state(&sci_rnc->sm, SCI_RNC_READY);
 409                         break;
 410                 default:
 411                         goto out;
 412                 }
 413                 break;
 414         case SCI_RNC_INVALIDATING:
 415                 if (scu_get_event_code(event_code) == SCU_EVENT_POST_RNC_INVALIDATE_COMPLETE) {
 416                         if (sci_rnc->destination_state == RNC_DEST_FINAL)
 417                                 next_state = SCI_RNC_INITIAL;
 418                         else
 419                                 next_state = SCI_RNC_POSTING;
 420                         sci_change_state(&sci_rnc->sm, next_state);
 421                 } else {
 422                         switch (scu_get_event_type(event_code)) {
 423                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
 424                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
 425                                 /* We really dont care if the hardware is going to suspend
 426                                  * the device since it's being invalidated anyway */
 427                                 dev_dbg(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 428                                         "%s: SCIC Remote Node Context 0x%p was "
 429                                         "suspeneded by hardware while being "
 430                                         "invalidated.\n", __func__, sci_rnc);
 431                                 break;
 432                         default:
 433                                 goto out;
 434                         }
 435                 }
 436                 break;
 437         case SCI_RNC_RESUMING:
 438                 if (scu_get_event_code(event_code) == SCU_EVENT_POST_RCN_RELEASE) {
 439                         sci_change_state(&sci_rnc->sm, SCI_RNC_READY);
 440                 } else {
 441                         switch (scu_get_event_type(event_code)) {
 442                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
 443                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
 444                                 /* We really dont care if the hardware is going to suspend
 445                                  * the device since it's being resumed anyway */
 446                                 dev_dbg(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 447                                         "%s: SCIC Remote Node Context 0x%p was "
 448                                         "suspeneded by hardware while being resumed.\n",
 449                                         __func__, sci_rnc);
 450                                 break;
 451                         default:
 452                                 goto out;
 453                         }
 454                 }
 455                 break;
 456         case SCI_RNC_READY:
 457                 switch (scu_get_event_type(event_code)) {
 458                 case SCU_EVENT_TL_RNC_SUSPEND_TX:
 459                         sci_change_state(&sci_rnc->sm, SCI_RNC_TX_SUSPENDED);
 460                         sci_rnc->suspend_type = scu_get_event_type(event_code);
 461                         break;
 462                 case SCU_EVENT_TL_RNC_SUSPEND_TX_RX:
 463                         sci_change_state(&sci_rnc->sm, SCI_RNC_TX_RX_SUSPENDED);
 464                         sci_rnc->suspend_type = scu_get_event_type(event_code);
 465                         break;
 466                 default:
 467                         goto out;
 468                 }
 469                 break;
 470         case SCI_RNC_AWAIT_SUSPENSION:
 471                 switch (scu_get_event_type(event_code)) {
 472                 case SCU_EVENT_TL_RNC_SUSPEND_TX:
 473                         next_state = SCI_RNC_TX_SUSPENDED;
 474                         break;
 475                 case SCU_EVENT_TL_RNC_SUSPEND_TX_RX:
 476                         next_state = SCI_RNC_TX_RX_SUSPENDED;
 477                         break;
 478                 default:
 479                         goto out;
 480                 }
 481                 if (sci_rnc->suspend_type == scu_get_event_type(event_code))
 482                         sci_change_state(&sci_rnc->sm, next_state);
 483                 break;
 484         default:
 485                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 486                          "%s: invalid state: %s\n", __func__,
 487                          rnc_state_name(state));
 488                 return SCI_FAILURE_INVALID_STATE;
 489         }
 490         return SCI_SUCCESS;
 491
 492  out:
 493         dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 494                  "%s: code: %#x state: %s\n", __func__, event_code,
 495                  rnc_state_name(state));
 496         return SCI_FAILURE;
 497
 498 }
 499
 500 enum sci_status sci_remote_node_context_destruct(struct sci_remote_node_context *sci_rnc,
 501                                                       scics_sds_remote_node_context_callback cb_fn,
 502                                                       void *cb_p)
 503 {
 504         enum scis_sds_remote_node_context_states state;
 505
 506         state = sci_rnc->sm.current_state_id;
 507         switch (state) {
 508         case SCI_RNC_INVALIDATING:
 509                 sci_remote_node_context_setup_to_destroy(sci_rnc, cb_fn, cb_p);
 510                 return SCI_SUCCESS;
 511         case SCI_RNC_POSTING:
 512         case SCI_RNC_RESUMING:
 513         case SCI_RNC_READY:
 514         case SCI_RNC_TX_SUSPENDED:
 515         case SCI_RNC_TX_RX_SUSPENDED:
 516         case SCI_RNC_AWAIT_SUSPENSION:
 517                 sci_remote_node_context_setup_to_destroy(sci_rnc, cb_fn, cb_p);
 518                 sci_change_state(&sci_rnc->sm, SCI_RNC_INVALIDATING);
 519                 return SCI_SUCCESS;
 520         case SCI_RNC_INITIAL:
 521                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 522                          "%s: invalid state: %s\n", __func__,
 523                          rnc_state_name(state));
 524                 /* We have decided that the destruct request on the remote node context
 525                  * can not fail since it is either in the initial/destroyed state or is
 526                  * can be destroyed.
 527                  */
 528                 return SCI_SUCCESS;
 529         default:
 530                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 531                          "%s: invalid state %s\n", __func__,
 532                          rnc_state_name(state));
 533                 return SCI_FAILURE_INVALID_STATE;
 534         }
 535 }
 536
 537 enum sci_status sci_remote_node_context_suspend(
 538                         struct sci_remote_node_context *sci_rnc,
 539                         enum sci_remote_node_suspension_reasons suspend_reason,
 540                         u32 suspend_type,
 541                         scics_sds_remote_node_context_callback cb_fn,
 542                         void *cb_p)
 543 {
 544         enum scis_sds_remote_node_context_states state
 545                 = sci_rnc->sm.current_state_id;
 546         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 547         enum sci_status status = SCI_FAILURE_INVALID_STATE;
 548         enum sci_remote_node_context_destination_state dest_param =
 549                 RNC_DEST_UNSPECIFIED;
 550
 551         dev_dbg(scirdev_to_dev(idev),
 552                 "%s: current state %d, current suspend_type %x dest state %d,"
 553                         " arg suspend_reason %d, arg suspend_type %x",
 554                 __func__, state, sci_rnc->suspend_type,
 555                 sci_rnc->destination_state, suspend_reason,
 556                 suspend_type);
 557
 558         /* Disable automatic state continuations if explicitly suspending. */
 559         if ((suspend_reason != SCI_SOFTWARE_SUSPENSION) ||
 560             (sci_rnc->destination_state == RNC_DEST_FINAL))
 561                 dest_param = sci_rnc->destination_state;
 562
 563         switch (state) {
 564         case SCI_RNC_RESUMING:
 565                 break;  /* The RNC has been posted, so start the suspend. */
 566         case SCI_RNC_READY:
 567                 break;
 568         case SCI_RNC_INVALIDATING:
 569                 if (sci_rnc->destination_state == RNC_DEST_FINAL) {
 570                         dev_warn(scirdev_to_dev(idev),
 571                                  "%s: already destroying %p\n",
 572                                  __func__, sci_rnc);
 573                         return SCI_FAILURE_INVALID_STATE;
 574                 }
 575                 /* Fall through and handle like SCI_RNC_POSTING */
 576         case SCI_RNC_POSTING:
 577                 /* Set the destination state to AWAIT - this signals the
 578                  * entry into the SCI_RNC_READY state that a suspension
 579                  * needs to be done immediately.
 580                  */
 581                 sci_rnc->destination_state = RNC_DEST_SUSPENDED;
 582                 return SCI_SUCCESS;
 583
 584         case SCI_RNC_TX_SUSPENDED:
 585                 if (suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX)
 586                         status = SCI_SUCCESS;
 587                 break;
 588         case SCI_RNC_TX_RX_SUSPENDED:
 589                 if (suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX_RX)
 590                         status = SCI_SUCCESS;
 591                 break;
 592         case SCI_RNC_AWAIT_SUSPENSION:
 593                 if ((sci_rnc->suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX_RX)
 594                     || (suspend_type == sci_rnc->suspend_type))
 595                         return SCI_SUCCESS;
 596                 break;
 597         default:
 598                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 599                          "%s: invalid state %s\n", __func__,
 600                          rnc_state_name(state));
 601                 return SCI_FAILURE_INVALID_STATE;
 602         }
 603         sci_rnc->destination_state = dest_param;
 604         sci_rnc->user_callback = cb_fn;
 605         sci_rnc->user_cookie   = cb_p;
 606         sci_rnc->suspend_type  = suspend_type;
 607
 608         if (status == SCI_SUCCESS) { /* Already in the destination state? */
 609                 struct isci_host *ihost = idev->owning_port->owning_controller;
 610
 611                 sci_remote_node_context_notify_user(sci_rnc);
 612                 wake_up_all(&ihost->eventq); /* Let observers look. */
 613                 return SCI_SUCCESS;
 614         }
 615         if (suspend_reason == SCI_SOFTWARE_SUSPENSION) {
 616                 isci_dev_set_hang_detection_timeout(idev, 0x00000001);
 617                 sci_remote_device_post_request(
 618                         idev, SCI_SOFTWARE_SUSPEND_CMD);
 619         }
 620         if (state != SCI_RNC_AWAIT_SUSPENSION)
 621                 sci_change_state(&sci_rnc->sm, SCI_RNC_AWAIT_SUSPENSION);
 622
 623         return SCI_SUCCESS;
 624 }
 625
 626 enum sci_status sci_remote_node_context_resume(struct sci_remote_node_context *sci_rnc,
 627                                                     scics_sds_remote_node_context_callback cb_fn,
 628                                                     void *cb_p)
 629 {
 630         enum scis_sds_remote_node_context_states state;
 631
 632         state = sci_rnc->sm.current_state_id;
 633         switch (state) {
 634         case SCI_RNC_INITIAL:
 635                 if (sci_rnc->remote_node_index == SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX)
 636                         return SCI_FAILURE_INVALID_STATE;
 637
 638                 sci_remote_node_context_setup_to_resume(sci_rnc, cb_fn, cb_p,
 639                                                         RNC_DEST_READY);
 640                 sci_remote_node_context_construct_buffer(sci_rnc);
 641                 sci_change_state(&sci_rnc->sm, SCI_RNC_POSTING);
 642                 return SCI_SUCCESS;
 643         case SCI_RNC_POSTING:
 644         case SCI_RNC_INVALIDATING:
 645         case SCI_RNC_RESUMING:
 646                 /* We are still waiting to post when a resume was requested. */
 647                 switch (sci_rnc->destination_state) {
 648                 case RNC_DEST_SUSPENDED:
 649                 case RNC_DEST_SUSPENDED_RESUME:
 650                         /* Previously waiting to suspend after posting.  Now
 651                          * continue onto resumption.
 652                          */
 653                         sci_remote_node_context_setup_to_resume(
 654                                 sci_rnc, cb_fn, cb_p,
 655                                 RNC_DEST_SUSPENDED_RESUME);
 656                         break;
 657                 default:
 658                         sci_remote_node_context_setup_to_resume(
 659                                 sci_rnc, cb_fn, cb_p,
 660                                 RNC_DEST_READY);
 661                         break;
 662                 }
 663                 return SCI_SUCCESS;
 664         case SCI_RNC_TX_SUSPENDED:
 665         case SCI_RNC_TX_RX_SUSPENDED: {
 666                 struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 667                 struct domain_device *dev = idev->domain_dev;
 668
 669                 /* If this is an expander attached SATA device we must
 670                  * invalidate and repost the RNC since this is the only way
 671                  * to clear the TCi to NCQ tag mapping table for the RNi.
 672                  * All other device types we can just resume.
 673                  */
 674                 sci_remote_node_context_setup_to_resume(sci_rnc, cb_fn, cb_p,
 675                                                         RNC_DEST_READY);
 676
 677                 if (dev_is_sata(dev) && dev->parent)
 678                         sci_change_state(&sci_rnc->sm, SCI_RNC_INVALIDATING);
 679                 else
 680                         sci_change_state(&sci_rnc->sm, SCI_RNC_RESUMING);
 681                 return SCI_SUCCESS;
 682         }
 683         case SCI_RNC_AWAIT_SUSPENSION:
 684                 sci_remote_node_context_setup_to_resume(
 685                         sci_rnc, cb_fn, cb_p,
 686                         RNC_DEST_SUSPENDED_RESUME);
 687                 return SCI_SUCCESS;
 688         default:
 689                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 690                          "%s: invalid state %s\n", __func__,
 691                          rnc_state_name(state));
 692                 return SCI_FAILURE_INVALID_STATE;
 693         }
 694 }
 695
 696 enum sci_status sci_remote_node_context_start_io(struct sci_remote_node_context *sci_rnc,
 697                                                              struct isci_request *ireq)
 698 {
 699         enum scis_sds_remote_node_context_states state;
 700
 701         state = sci_rnc->sm.current_state_id;
 702
 703         switch (state) {
 704         case SCI_RNC_READY:
 705                 return SCI_SUCCESS;
 706         case SCI_RNC_TX_SUSPENDED:
 707         case SCI_RNC_TX_RX_SUSPENDED:
 708         case SCI_RNC_AWAIT_SUSPENSION:
 709                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 710                          "%s: invalid state %s\n", __func__,
 711                          rnc_state_name(state));
 712                 return SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED;
 713         default:
 714                 dev_dbg(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 715                         "%s: invalid state %s\n", __func__,
 716                         rnc_state_name(state));
 717                 return SCI_FAILURE_INVALID_STATE;
 718         }
 719 }
 720
 721 enum sci_status sci_remote_node_context_start_task(
 722         struct sci_remote_node_context *sci_rnc,
 723         struct isci_request *ireq,
 724         scics_sds_remote_node_context_callback cb_fn,
 725         void *cb_p)
 726 {
 727         enum sci_status status = sci_remote_node_context_resume(sci_rnc,
 728                                                                 cb_fn, cb_p);
 729         if (status != SCI_SUCCESS)
 730                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 731                         "%s: resume failed: %d\n", __func__, status);
 732         return status;
 733 }
 734
 735 int sci_remote_node_context_is_safe_to_abort(
 736         struct sci_remote_node_context *sci_rnc)
 737 {
 738         enum scis_sds_remote_node_context_states state;
 739
 740         state = sci_rnc->sm.current_state_id;
 741         switch (state) {
 742         case SCI_RNC_INVALIDATING:
 743         case SCI_RNC_TX_RX_SUSPENDED:
 744                 return 1;
 745         case SCI_RNC_POSTING:
 746         case SCI_RNC_RESUMING:
 747         case SCI_RNC_READY:
 748         case SCI_RNC_TX_SUSPENDED:
 749         case SCI_RNC_AWAIT_SUSPENSION:
 750         case SCI_RNC_INITIAL:
 751                 return 0;
 752         default:
 753                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 754                          "%s: invalid state %d\n", __func__, state);
 755                 return 0;
 756         }
 757 }