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
  64 /**
  65  *
  66  * @sci_rnc: The RNC for which the is posted request is being made.
  67  *
  68  * This method will return true if the RNC is not in the initial state.  In all
  69  * other states the RNC is considered active and this will return true. The
  70  * destroy request of the state machine drives the RNC back to the initial
  71  * state.  If the state machine changes then this routine will also have to be
  72  * changed. bool true if the state machine is not in the initial state false if
  73  * the state machine is in the initial state
  74  */
  75
  76 /**
  77  *
  78  * @sci_rnc: The state of the remote node context object to check.
  79  *
  80  * This method will return true if the remote node context is in a READY state
  81  * otherwise it will return false bool true if the remote node context is in
  82  * the ready state. false if the remote node context is not in the ready state.
  83  */
  84 bool scic_sds_remote_node_context_is_ready(
  85         struct scic_sds_remote_node_context *sci_rnc)
  86 {
  87         u32 current_state = sci_rnc->sm.current_state_id;
  88
  89         if (current_state == SCI_RNC_READY) {
  90                 return true;
  91         }
  92
  93         return false;
  94 }
  95
  96 /**
  97  *
  98  * @sci_dev: The remote device to use to construct the RNC buffer.
  99  * @rnc: The buffer into which the remote device data will be copied.
 100  *
 101  * This method will construct the RNC buffer for this remote device object. none
 102  */
 103 static void scic_sds_remote_node_context_construct_buffer(
 104         struct scic_sds_remote_node_context *sci_rnc)
 105 {
 106         struct scic_sds_remote_device *sci_dev = rnc_to_dev(sci_rnc);
 107         struct domain_device *dev = sci_dev_to_domain(sci_dev);
 108         int rni = sci_rnc->remote_node_index;
 109         union scu_remote_node_context *rnc;
 110         struct scic_sds_controller *scic;
 111         __le64 sas_addr;
 112
 113         scic = scic_sds_remote_device_get_controller(sci_dev);
 114         rnc = scic_sds_controller_get_remote_node_context_buffer(scic, rni);
 115
 116         memset(rnc, 0, sizeof(union scu_remote_node_context)
 117                 * scic_sds_remote_device_node_count(sci_dev));
 118
 119         rnc->ssp.remote_node_index = rni;
 120         rnc->ssp.remote_node_port_width = sci_dev->device_port_width;
 121         rnc->ssp.logical_port_index = sci_dev->owning_port->physical_port_index;
 122
 123         /* sas address is __be64, context ram format is __le64 */
 124         sas_addr = cpu_to_le64(SAS_ADDR(dev->sas_addr));
 125         rnc->ssp.remote_sas_address_hi = upper_32_bits(sas_addr);
 126         rnc->ssp.remote_sas_address_lo = lower_32_bits(sas_addr);
 127
 128         rnc->ssp.nexus_loss_timer_enable = true;
 129         rnc->ssp.check_bit               = false;
 130         rnc->ssp.is_valid                = false;
 131         rnc->ssp.is_remote_node_context  = true;
 132         rnc->ssp.function_number         = 0;
 133
 134         rnc->ssp.arbitration_wait_time = 0;
 135
 136         if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP)) {
 137                 rnc->ssp.connection_occupancy_timeout =
 138                         scic->user_parameters.sds1.stp_max_occupancy_timeout;
 139                 rnc->ssp.connection_inactivity_timeout =
 140                         scic->user_parameters.sds1.stp_inactivity_timeout;
 141         } else {
 142                 rnc->ssp.connection_occupancy_timeout  =
 143                         scic->user_parameters.sds1.ssp_max_occupancy_timeout;
 144                 rnc->ssp.connection_inactivity_timeout =
 145                         scic->user_parameters.sds1.ssp_inactivity_timeout;
 146         }
 147
 148         rnc->ssp.initial_arbitration_wait_time = 0;
 149
 150         /* Open Address Frame Parameters */
 151         rnc->ssp.oaf_connection_rate = sci_dev->connection_rate;
 152         rnc->ssp.oaf_features = 0;
 153         rnc->ssp.oaf_source_zone_group = 0;
 154         rnc->ssp.oaf_more_compatibility_features = 0;
 155 }
 156
 157 /**
 158  *
 159  * @sci_rnc:
 160  * @callback:
 161  * @callback_parameter:
 162  *
 163  * This method will setup the remote node context object so it will transition
 164  * to its ready state.  If the remote node context is already setup to
 165  * transition to its final state then this function does nothing. none
 166  */
 167 static void scic_sds_remote_node_context_setup_to_resume(
 168         struct scic_sds_remote_node_context *sci_rnc,
 169         scics_sds_remote_node_context_callback callback,
 170         void *callback_parameter)
 171 {
 172         if (sci_rnc->destination_state != SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_FINAL) {
 173                 sci_rnc->destination_state = SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_READY;
 174                 sci_rnc->user_callback     = callback;
 175                 sci_rnc->user_cookie       = callback_parameter;
 176         }
 177 }
 178
 179 static void scic_sds_remote_node_context_setup_to_destory(
 180         struct scic_sds_remote_node_context *sci_rnc,
 181         scics_sds_remote_node_context_callback callback,
 182         void *callback_parameter)
 183 {
 184         sci_rnc->destination_state = SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_FINAL;
 185         sci_rnc->user_callback     = callback;
 186         sci_rnc->user_cookie       = callback_parameter;
 187 }
 188
 189 /**
 190  *
 191  *
 192  * This method just calls the user callback function and then resets the
 193  * callback.
 194  */
 195 static void scic_sds_remote_node_context_notify_user(
 196         struct scic_sds_remote_node_context *rnc)
 197 {
 198         if (rnc->user_callback != NULL) {
 199                 (*rnc->user_callback)(rnc->user_cookie);
 200
 201                 rnc->user_callback = NULL;
 202                 rnc->user_cookie = NULL;
 203         }
 204 }
 205
 206 static void scic_sds_remote_node_context_continue_state_transitions(struct scic_sds_remote_node_context *rnc)
 207 {
 208         if (rnc->destination_state == SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_READY)
 209                 scic_sds_remote_node_context_resume(rnc, rnc->user_callback,
 210                                                     rnc->user_cookie);
 211 }
 212
 213 /**
 214  *
 215  * @sci_rnc: The remote node context object that is to be validated.
 216  *
 217  * This method will mark the rnc buffer as being valid and post the request to
 218  * the hardware. none
 219  */
 220 static void scic_sds_remote_node_context_validate_context_buffer(
 221         struct scic_sds_remote_node_context *sci_rnc)
 222 {
 223         struct scic_sds_remote_device *sci_dev = rnc_to_dev(sci_rnc);
 224         struct domain_device *dev = sci_dev_to_domain(sci_dev);
 225         union scu_remote_node_context *rnc_buffer;
 226
 227         rnc_buffer = scic_sds_controller_get_remote_node_context_buffer(
 228                 scic_sds_remote_device_get_controller(sci_dev),
 229                 sci_rnc->remote_node_index
 230                 );
 231
 232         rnc_buffer->ssp.is_valid = true;
 233
 234         if (!sci_dev->is_direct_attached &&
 235             (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP))) {
 236                 scic_sds_remote_device_post_request(sci_dev,
 237                                                     SCU_CONTEXT_COMMAND_POST_RNC_96);
 238         } else {
 239                 scic_sds_remote_device_post_request(sci_dev, SCU_CONTEXT_COMMAND_POST_RNC_32);
 240
 241                 if (sci_dev->is_direct_attached) {
 242                         scic_sds_port_setup_transports(sci_dev->owning_port,
 243                                                        sci_rnc->remote_node_index);
 244                 }
 245         }
 246 }
 247
 248 /**
 249  *
 250  * @sci_rnc: The remote node context object that is to be invalidated.
 251  *
 252  * This method will update the RNC buffer and post the invalidate request. none
 253  */
 254 static void scic_sds_remote_node_context_invalidate_context_buffer(
 255         struct scic_sds_remote_node_context *sci_rnc)
 256 {
 257         union scu_remote_node_context *rnc_buffer;
 258
 259         rnc_buffer = scic_sds_controller_get_remote_node_context_buffer(
 260                 scic_sds_remote_device_get_controller(rnc_to_dev(sci_rnc)),
 261                 sci_rnc->remote_node_index);
 262
 263         rnc_buffer->ssp.is_valid = false;
 264
 265         scic_sds_remote_device_post_request(rnc_to_dev(sci_rnc),
 266                                             SCU_CONTEXT_COMMAND_POST_RNC_INVALIDATE);
 267 }
 268
 269 static void scic_sds_remote_node_context_initial_state_enter(struct sci_base_state_machine *sm)
 270 {
 271         struct scic_sds_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 272
 273         /* Check to see if we have gotten back to the initial state because
 274          * someone requested to destroy the remote node context object.
 275          */
 276         if (sm->previous_state_id == SCI_RNC_INVALIDATING) {
 277                 rnc->destination_state = SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_UNSPECIFIED;
 278                 scic_sds_remote_node_context_notify_user(rnc);
 279         }
 280 }
 281
 282 static void scic_sds_remote_node_context_posting_state_enter(struct sci_base_state_machine *sm)
 283 {
 284         struct scic_sds_remote_node_context *sci_rnc = container_of(sm, typeof(*sci_rnc), sm);
 285
 286         scic_sds_remote_node_context_validate_context_buffer(sci_rnc);
 287 }
 288
 289 static void scic_sds_remote_node_context_invalidating_state_enter(struct sci_base_state_machine *sm)
 290 {
 291         struct scic_sds_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 292
 293         scic_sds_remote_node_context_invalidate_context_buffer(rnc);
 294 }
 295
 296 static void scic_sds_remote_node_context_resuming_state_enter(struct sci_base_state_machine *sm)
 297 {
 298         struct scic_sds_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 299         struct scic_sds_remote_device *sci_dev;
 300         struct domain_device *dev;
 301
 302         sci_dev = rnc_to_dev(rnc);
 303         dev = sci_dev_to_domain(sci_dev);
 304
 305         /*
 306          * For direct attached SATA devices we need to clear the TLCR
 307          * NCQ to TCi tag mapping on the phy and in cases where we
 308          * resume because of a target reset we also need to update
 309          * the STPTLDARNI register with the RNi of the device
 310          */
 311         if ((dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP)) &&
 312             sci_dev->is_direct_attached)
 313                 scic_sds_port_setup_transports(sci_dev->owning_port,
 314                                                rnc->remote_node_index);
 315
 316         scic_sds_remote_device_post_request(sci_dev, SCU_CONTEXT_COMMAND_POST_RNC_RESUME);
 317 }
 318
 319 static void scic_sds_remote_node_context_ready_state_enter(struct sci_base_state_machine *sm)
 320 {
 321         struct scic_sds_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 322
 323         rnc->destination_state = SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_UNSPECIFIED;
 324
 325         if (rnc->user_callback)
 326                 scic_sds_remote_node_context_notify_user(rnc);
 327 }
 328
 329 static void scic_sds_remote_node_context_tx_suspended_state_enter(struct sci_base_state_machine *sm)
 330 {
 331         struct scic_sds_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 332
 333         scic_sds_remote_node_context_continue_state_transitions(rnc);
 334 }
 335
 336 static void scic_sds_remote_node_context_tx_rx_suspended_state_enter(struct sci_base_state_machine *sm)
 337 {
 338         struct scic_sds_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 339
 340         scic_sds_remote_node_context_continue_state_transitions(rnc);
 341 }
 342
 343 static const struct sci_base_state scic_sds_remote_node_context_state_table[] = {
 344         [SCI_RNC_INITIAL] = {
 345                 .enter_state = scic_sds_remote_node_context_initial_state_enter,
 346         },
 347         [SCI_RNC_POSTING] = {
 348                 .enter_state = scic_sds_remote_node_context_posting_state_enter,
 349         },
 350         [SCI_RNC_INVALIDATING] = {
 351                 .enter_state = scic_sds_remote_node_context_invalidating_state_enter,
 352         },
 353         [SCI_RNC_RESUMING] = {
 354                 .enter_state = scic_sds_remote_node_context_resuming_state_enter,
 355         },
 356         [SCI_RNC_READY] = {
 357                 .enter_state = scic_sds_remote_node_context_ready_state_enter,
 358         },
 359         [SCI_RNC_TX_SUSPENDED] = {
 360                 .enter_state = scic_sds_remote_node_context_tx_suspended_state_enter,
 361         },
 362         [SCI_RNC_TX_RX_SUSPENDED] = {
 363                 .enter_state = scic_sds_remote_node_context_tx_rx_suspended_state_enter,
 364         },
 365         [SCI_RNC_AWAIT_SUSPENSION] = { },
 366 };
 367
 368 void scic_sds_remote_node_context_construct(struct scic_sds_remote_node_context *rnc,
 369                                             u16 remote_node_index)
 370 {
 371         memset(rnc, 0, sizeof(struct scic_sds_remote_node_context));
 372
 373         rnc->remote_node_index = remote_node_index;
 374         rnc->destination_state = SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_UNSPECIFIED;
 375
 376         sci_init_sm(&rnc->sm, scic_sds_remote_node_context_state_table, SCI_RNC_INITIAL);
 377 }
 378
 379 enum sci_status scic_sds_remote_node_context_event_handler(struct scic_sds_remote_node_context *sci_rnc,
 380                                                            u32 event_code)
 381 {
 382         enum scis_sds_remote_node_context_states state;
 383
 384         state = sci_rnc->sm.current_state_id;
 385         switch (state) {
 386         case SCI_RNC_POSTING:
 387                 switch (scu_get_event_code(event_code)) {
 388                 case SCU_EVENT_POST_RNC_COMPLETE:
 389                         sci_change_state(&sci_rnc->sm, SCI_RNC_READY);
 390                         break;
 391                 default:
 392                         goto out;
 393                 }
 394                 break;
 395         case SCI_RNC_INVALIDATING:
 396                 if (scu_get_event_code(event_code) == SCU_EVENT_POST_RNC_INVALIDATE_COMPLETE) {
 397                         if (sci_rnc->destination_state == SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_FINAL)
 398                                 state = SCI_RNC_INITIAL;
 399                         else
 400                                 state = SCI_RNC_POSTING;
 401                         sci_change_state(&sci_rnc->sm, state);
 402                 } else {
 403                         switch (scu_get_event_type(event_code)) {
 404                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
 405                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
 406                                 /* We really dont care if the hardware is going to suspend
 407                                  * the device since it's being invalidated anyway */
 408                                 dev_dbg(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 409                                         "%s: SCIC Remote Node Context 0x%p was "
 410                                         "suspeneded by hardware while being "
 411                                         "invalidated.\n", __func__, sci_rnc);
 412                                 break;
 413                         default:
 414                                 goto out;
 415                         }
 416                 }
 417                 break;
 418         case SCI_RNC_RESUMING:
 419                 if (scu_get_event_code(event_code) == SCU_EVENT_POST_RCN_RELEASE) {
 420                         sci_change_state(&sci_rnc->sm, SCI_RNC_READY);
 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 resumed 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 resumed.\n",
 430                                         __func__, sci_rnc);
 431                                 break;
 432                         default:
 433                                 goto out;
 434                         }
 435                 }
 436                 break;
 437         case SCI_RNC_READY:
 438                 switch (scu_get_event_type(event_code)) {
 439                 case SCU_EVENT_TL_RNC_SUSPEND_TX:
 440                         sci_change_state(&sci_rnc->sm, SCI_RNC_TX_SUSPENDED);
 441                         sci_rnc->suspension_code = scu_get_event_specifier(event_code);
 442                         break;
 443                 case SCU_EVENT_TL_RNC_SUSPEND_TX_RX:
 444                         sci_change_state(&sci_rnc->sm, SCI_RNC_TX_RX_SUSPENDED);
 445                         sci_rnc->suspension_code = scu_get_event_specifier(event_code);
 446                         break;
 447                 default:
 448                         goto out;
 449                 }
 450                 break;
 451         case SCI_RNC_AWAIT_SUSPENSION:
 452                 switch (scu_get_event_type(event_code)) {
 453                 case SCU_EVENT_TL_RNC_SUSPEND_TX:
 454                         sci_change_state(&sci_rnc->sm, SCI_RNC_TX_SUSPENDED);
 455                         sci_rnc->suspension_code = scu_get_event_specifier(event_code);
 456                         break;
 457                 case SCU_EVENT_TL_RNC_SUSPEND_TX_RX:
 458                         sci_change_state(&sci_rnc->sm, SCI_RNC_TX_RX_SUSPENDED);
 459                         sci_rnc->suspension_code = scu_get_event_specifier(event_code);
 460                         break;
 461                 default:
 462                         goto out;
 463                 }
 464                 break;
 465         default:
 466                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 467                          "%s: invalid state %d\n", __func__, state);
 468                 return SCI_FAILURE_INVALID_STATE;
 469         }
 470         return SCI_SUCCESS;
 471
 472  out:
 473         dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 474                  "%s: code: %#x state: %d\n", __func__, event_code, state);
 475         return SCI_FAILURE;
 476
 477 }
 478
 479 enum sci_status scic_sds_remote_node_context_destruct(struct scic_sds_remote_node_context *sci_rnc,
 480                                                       scics_sds_remote_node_context_callback cb_fn,
 481                                                       void *cb_p)
 482 {
 483         enum scis_sds_remote_node_context_states state;
 484
 485         state = sci_rnc->sm.current_state_id;
 486         switch (state) {
 487         case SCI_RNC_INVALIDATING:
 488                 scic_sds_remote_node_context_setup_to_destory(sci_rnc, cb_fn, cb_p);
 489                 return SCI_SUCCESS;
 490         case SCI_RNC_POSTING:
 491         case SCI_RNC_RESUMING:
 492         case SCI_RNC_READY:
 493         case SCI_RNC_TX_SUSPENDED:
 494         case SCI_RNC_TX_RX_SUSPENDED:
 495         case SCI_RNC_AWAIT_SUSPENSION:
 496                 scic_sds_remote_node_context_setup_to_destory(sci_rnc, cb_fn, cb_p);
 497                 sci_change_state(&sci_rnc->sm, SCI_RNC_INVALIDATING);
 498                 return SCI_SUCCESS;
 499         case SCI_RNC_INITIAL:
 500                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 501                          "%s: invalid state %d\n", __func__, state);
 502                 /* We have decided that the destruct request on the remote node context
 503                  * can not fail since it is either in the initial/destroyed state or is
 504                  * can be destroyed.
 505                  */
 506                 return SCI_SUCCESS;
 507         default:
 508                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 509                          "%s: invalid state %d\n", __func__, state);
 510                 return SCI_FAILURE_INVALID_STATE;
 511         }
 512 }
 513
 514 enum sci_status scic_sds_remote_node_context_suspend(struct scic_sds_remote_node_context *sci_rnc,
 515                                                      u32 suspend_type,
 516                                                      scics_sds_remote_node_context_callback cb_fn,
 517                                                      void *cb_p)
 518 {
 519         enum scis_sds_remote_node_context_states state;
 520
 521         state = sci_rnc->sm.current_state_id;
 522         if (state != SCI_RNC_READY) {
 523                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 524                          "%s: invalid state %d\n", __func__, state);
 525                 return SCI_FAILURE_INVALID_STATE;
 526         }
 527
 528         sci_rnc->user_callback   = cb_fn;
 529         sci_rnc->user_cookie     = cb_p;
 530         sci_rnc->suspension_code = suspend_type;
 531
 532         if (suspend_type == SCI_SOFTWARE_SUSPENSION) {
 533                 scic_sds_remote_device_post_request(rnc_to_dev(sci_rnc),
 534                                                     SCU_CONTEXT_COMMAND_POST_RNC_SUSPEND_TX);
 535         }
 536
 537         sci_change_state(&sci_rnc->sm, SCI_RNC_AWAIT_SUSPENSION);
 538         return SCI_SUCCESS;
 539 }
 540
 541 enum sci_status scic_sds_remote_node_context_resume(struct scic_sds_remote_node_context *sci_rnc,
 542                                                     scics_sds_remote_node_context_callback cb_fn,
 543                                                     void *cb_p)
 544 {
 545         enum scis_sds_remote_node_context_states state;
 546
 547         state = sci_rnc->sm.current_state_id;
 548         switch (state) {
 549         case SCI_RNC_INITIAL:
 550                 if (sci_rnc->remote_node_index == SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX)
 551                         return SCI_FAILURE_INVALID_STATE;
 552
 553                 scic_sds_remote_node_context_setup_to_resume(sci_rnc, cb_fn, cb_p);
 554                 scic_sds_remote_node_context_construct_buffer(sci_rnc);
 555                 sci_change_state(&sci_rnc->sm, SCI_RNC_POSTING);
 556                 return SCI_SUCCESS;
 557         case SCI_RNC_POSTING:
 558         case SCI_RNC_INVALIDATING:
 559         case SCI_RNC_RESUMING:
 560                 if (sci_rnc->destination_state != SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_READY)
 561                         return SCI_FAILURE_INVALID_STATE;
 562
 563                 sci_rnc->user_callback = cb_fn;
 564                 sci_rnc->user_cookie   = cb_p;
 565                 return SCI_SUCCESS;
 566         case SCI_RNC_TX_SUSPENDED: {
 567                 struct scic_sds_remote_device *sci_dev = rnc_to_dev(sci_rnc);
 568                 struct domain_device *dev = sci_dev_to_domain(sci_dev);
 569
 570                 scic_sds_remote_node_context_setup_to_resume(sci_rnc, cb_fn, cb_p);
 571
 572                 /* TODO: consider adding a resume action of NONE, INVALIDATE, WRITE_TLCR */
 573                 if (dev->dev_type == SAS_END_DEV || dev_is_expander(dev))
 574                         sci_change_state(&sci_rnc->sm, SCI_RNC_RESUMING);
 575                 else if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP)) {
 576                         if (sci_dev->is_direct_attached) {
 577                                 /* @todo Fix this since I am being silly in writing to the STPTLDARNI register. */
 578                                 sci_change_state(&sci_rnc->sm, SCI_RNC_RESUMING);
 579                         } else {
 580                                 sci_change_state(&sci_rnc->sm, SCI_RNC_INVALIDATING);
 581                         }
 582                 } else
 583                         return SCI_FAILURE;
 584                 return SCI_SUCCESS;
 585         }
 586         case SCI_RNC_TX_RX_SUSPENDED:
 587                 scic_sds_remote_node_context_setup_to_resume(sci_rnc, cb_fn, cb_p);
 588                 sci_change_state(&sci_rnc->sm, SCI_RNC_RESUMING);
 589                 return SCI_FAILURE_INVALID_STATE;
 590         case SCI_RNC_AWAIT_SUSPENSION:
 591                 scic_sds_remote_node_context_setup_to_resume(sci_rnc, cb_fn, cb_p);
 592                 return SCI_SUCCESS;
 593         default:
 594                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 595                          "%s: invalid state %d\n", __func__, state);
 596                 return SCI_FAILURE_INVALID_STATE;
 597         }
 598 }
 599
 600 enum sci_status scic_sds_remote_node_context_start_io(struct scic_sds_remote_node_context *sci_rnc,
 601                                                              struct scic_sds_request *sci_req)
 602 {
 603         enum scis_sds_remote_node_context_states state;
 604
 605         state = sci_rnc->sm.current_state_id;
 606
 607         switch (state) {
 608         case SCI_RNC_READY:
 609                 return SCI_SUCCESS;
 610         case SCI_RNC_TX_SUSPENDED:
 611         case SCI_RNC_TX_RX_SUSPENDED:
 612         case SCI_RNC_AWAIT_SUSPENSION:
 613                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 614                          "%s: invalid state %d\n", __func__, state);
 615                 return SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED;
 616         default:
 617                 break;
 618         }
 619         dev_dbg(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 620                 "%s: requested to start IO while still resuming, %d\n",
 621                 __func__, state);
 622         return SCI_FAILURE_INVALID_STATE;
 623 }
 624
 625 enum sci_status scic_sds_remote_node_context_start_task(struct scic_sds_remote_node_context *sci_rnc,
 626                                                         struct scic_sds_request *sci_req)
 627 {
 628         enum scis_sds_remote_node_context_states state;
 629
 630         state = sci_rnc->sm.current_state_id;
 631         switch (state) {
 632         case SCI_RNC_RESUMING:
 633         case SCI_RNC_READY:
 634         case SCI_RNC_AWAIT_SUSPENSION:
 635                 return SCI_SUCCESS;
 636         case SCI_RNC_TX_SUSPENDED:
 637         case SCI_RNC_TX_RX_SUSPENDED:
 638                 scic_sds_remote_node_context_resume(sci_rnc, NULL, NULL);
 639                 return SCI_SUCCESS;
 640         default:
 641                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 642                          "%s: invalid state %d\n", __func__, state);
 643                 return SCI_FAILURE_INVALID_STATE;
 644         }
 645 }