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         if (state >= ARRAY_SIZE(strings))
  70                 return "UNKNOWN";
  71
  72         return strings[state];
  73 }
  74 #undef C
  75
  76 /**
  77  * sci_remote_node_context_is_ready()
  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 sci_remote_node_context_is_ready(
  85         struct sci_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 bool sci_remote_node_context_is_suspended(struct sci_remote_node_context *sci_rnc)
  97 {
  98         u32 current_state = sci_rnc->sm.current_state_id;
  99
 100         if (current_state == SCI_RNC_TX_RX_SUSPENDED)
 101                 return true;
 102         return false;
 103 }
 104
 105 static union scu_remote_node_context *sci_rnc_by_id(struct isci_host *ihost, u16 id)
 106 {
 107         if (id < ihost->remote_node_entries &&
 108             ihost->device_table[id])
 109                 return &ihost->remote_node_context_table[id];
 110
 111         return NULL;
 112 }
 113
 114 static void sci_remote_node_context_construct_buffer(struct sci_remote_node_context *sci_rnc)
 115 {
 116         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 117         struct domain_device *dev = idev->domain_dev;
 118         int rni = sci_rnc->remote_node_index;
 119         union scu_remote_node_context *rnc;
 120         struct isci_host *ihost;
 121         __le64 sas_addr;
 122
 123         ihost = idev->owning_port->owning_controller;
 124         rnc = sci_rnc_by_id(ihost, rni);
 125
 126         memset(rnc, 0, sizeof(union scu_remote_node_context)
 127                 * sci_remote_device_node_count(idev));
 128
 129         rnc->ssp.remote_node_index = rni;
 130         rnc->ssp.remote_node_port_width = idev->device_port_width;
 131         rnc->ssp.logical_port_index = idev->owning_port->physical_port_index;
 132
 133         /* sas address is __be64, context ram format is __le64 */
 134         sas_addr = cpu_to_le64(SAS_ADDR(dev->sas_addr));
 135         rnc->ssp.remote_sas_address_hi = upper_32_bits(sas_addr);
 136         rnc->ssp.remote_sas_address_lo = lower_32_bits(sas_addr);
 137
 138         rnc->ssp.nexus_loss_timer_enable = true;
 139         rnc->ssp.check_bit               = false;
 140         rnc->ssp.is_valid                = false;
 141         rnc->ssp.is_remote_node_context  = true;
 142         rnc->ssp.function_number         = 0;
 143
 144         rnc->ssp.arbitration_wait_time = 0;
 145
 146         if (dev_is_sata(dev)) {
 147                 rnc->ssp.connection_occupancy_timeout =
 148                         ihost->user_parameters.stp_max_occupancy_timeout;
 149                 rnc->ssp.connection_inactivity_timeout =
 150                         ihost->user_parameters.stp_inactivity_timeout;
 151         } else {
 152                 rnc->ssp.connection_occupancy_timeout  =
 153                         ihost->user_parameters.ssp_max_occupancy_timeout;
 154                 rnc->ssp.connection_inactivity_timeout =
 155                         ihost->user_parameters.ssp_inactivity_timeout;
 156         }
 157
 158         rnc->ssp.initial_arbitration_wait_time = 0;
 159
 160         /* Open Address Frame Parameters */
 161         rnc->ssp.oaf_connection_rate = idev->connection_rate;
 162         rnc->ssp.oaf_features = 0;
 163         rnc->ssp.oaf_source_zone_group = 0;
 164         rnc->ssp.oaf_more_compatibility_features = 0;
 165 }
 166 /*
 167  * This method will setup the remote node context object so it will transition
 168  * to its ready state.  If the remote node context is already setup to
 169  * transition to its final state then this function does nothing. none
 170  */
 171 static void sci_remote_node_context_setup_to_resume(
 172         struct sci_remote_node_context *sci_rnc,
 173         scics_sds_remote_node_context_callback callback,
 174         void *callback_parameter,
 175         enum sci_remote_node_context_destination_state dest_param)
 176 {
 177         if (sci_rnc->destination_state != RNC_DEST_FINAL) {
 178                 sci_rnc->destination_state = dest_param;
 179                 if (callback != NULL) {
 180                         sci_rnc->user_callback = callback;
 181                         sci_rnc->user_cookie   = callback_parameter;
 182                 }
 183         }
 184 }
 185
 186 static void sci_remote_node_context_setup_to_destroy(
 187         struct sci_remote_node_context *sci_rnc,
 188         scics_sds_remote_node_context_callback callback,
 189         void *callback_parameter)
 190 {
 191         struct isci_host *ihost = idev_to_ihost(rnc_to_dev(sci_rnc));
 192
 193         sci_rnc->destination_state = RNC_DEST_FINAL;
 194         sci_rnc->user_callback     = callback;
 195         sci_rnc->user_cookie       = callback_parameter;
 196
 197         wake_up(&ihost->eventq);
 198 }
 199
 200 /*
 201  * This method just calls the user callback function and then resets the
 202  * callback.
 203  */
 204 static void sci_remote_node_context_notify_user(
 205         struct sci_remote_node_context *rnc)
 206 {
 207         if (rnc->user_callback != NULL) {
 208                 (*rnc->user_callback)(rnc->user_cookie);
 209
 210                 rnc->user_callback = NULL;
 211                 rnc->user_cookie = NULL;
 212         }
 213 }
 214
 215 static void sci_remote_node_context_continue_state_transitions(struct sci_remote_node_context *rnc)
 216 {
 217         switch (rnc->destination_state) {
 218         case RNC_DEST_READY:
 219         case RNC_DEST_SUSPENDED_RESUME:
 220                 rnc->destination_state = RNC_DEST_READY;
 221                 fallthrough;
 222         case RNC_DEST_FINAL:
 223                 sci_remote_node_context_resume(rnc, rnc->user_callback,
 224                                                rnc->user_cookie);
 225                 break;
 226         default:
 227                 rnc->destination_state = RNC_DEST_UNSPECIFIED;
 228                 break;
 229         }
 230 }
 231
 232 static void sci_remote_node_context_validate_context_buffer(struct sci_remote_node_context *sci_rnc)
 233 {
 234         union scu_remote_node_context *rnc_buffer;
 235         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 236         struct domain_device *dev = idev->domain_dev;
 237         struct isci_host *ihost = idev->owning_port->owning_controller;
 238
 239         rnc_buffer = sci_rnc_by_id(ihost, sci_rnc->remote_node_index);
 240
 241         rnc_buffer->ssp.is_valid = true;
 242
 243         if (dev_is_sata(dev) && dev->parent) {
 244                 sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_96);
 245         } else {
 246                 sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_32);
 247
 248                 if (!dev->parent)
 249                         sci_port_setup_transports(idev->owning_port,
 250                                                   sci_rnc->remote_node_index);
 251         }
 252 }
 253
 254 static void sci_remote_node_context_invalidate_context_buffer(struct sci_remote_node_context *sci_rnc)
 255 {
 256         union scu_remote_node_context *rnc_buffer;
 257         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 258         struct isci_host *ihost = idev->owning_port->owning_controller;
 259
 260         rnc_buffer = sci_rnc_by_id(ihost, sci_rnc->remote_node_index);
 261
 262         rnc_buffer->ssp.is_valid = false;
 263
 264         sci_remote_device_post_request(rnc_to_dev(sci_rnc),
 265                                        SCU_CONTEXT_COMMAND_POST_RNC_INVALIDATE);
 266 }
 267
 268 static void sci_remote_node_context_initial_state_enter(struct sci_base_state_machine *sm)
 269 {
 270         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 271         struct isci_remote_device *idev = rnc_to_dev(rnc);
 272         struct isci_host *ihost = idev->owning_port->owning_controller;
 273
 274         /* Check to see if we have gotten back to the initial state because
 275          * someone requested to destroy the remote node context object.
 276          */
 277         if (sm->previous_state_id == SCI_RNC_INVALIDATING) {
 278                 rnc->destination_state = RNC_DEST_UNSPECIFIED;
 279                 sci_remote_node_context_notify_user(rnc);
 280
 281                 smp_wmb();
 282                 wake_up(&ihost->eventq);
 283         }
 284 }
 285
 286 static void sci_remote_node_context_posting_state_enter(struct sci_base_state_machine *sm)
 287 {
 288         struct sci_remote_node_context *sci_rnc = container_of(sm, typeof(*sci_rnc), sm);
 289
 290         sci_remote_node_context_validate_context_buffer(sci_rnc);
 291 }
 292
 293 static void sci_remote_node_context_invalidating_state_enter(struct sci_base_state_machine *sm)
 294 {
 295         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 296
 297         /* Terminate all outstanding requests. */
 298         sci_remote_device_terminate_requests(rnc_to_dev(rnc));
 299         sci_remote_node_context_invalidate_context_buffer(rnc);
 300 }
 301
 302 static void sci_remote_node_context_resuming_state_enter(struct sci_base_state_machine *sm)
 303 {
 304         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 305         struct isci_remote_device *idev;
 306         struct domain_device *dev;
 307
 308         idev = rnc_to_dev(rnc);
 309         dev = idev->domain_dev;
 310
 311         /*
 312          * For direct attached SATA devices we need to clear the TLCR
 313          * NCQ to TCi tag mapping on the phy and in cases where we
 314          * resume because of a target reset we also need to update
 315          * the STPTLDARNI register with the RNi of the device
 316          */
 317         if (dev_is_sata(dev) && !dev->parent)
 318                 sci_port_setup_transports(idev->owning_port, rnc->remote_node_index);
 319
 320         sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_RESUME);
 321 }
 322
 323 static void sci_remote_node_context_ready_state_enter(struct sci_base_state_machine *sm)
 324 {
 325         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 326         enum sci_remote_node_context_destination_state dest_select;
 327         int tell_user = 1;
 328
 329         dest_select = rnc->destination_state;
 330         rnc->destination_state = RNC_DEST_UNSPECIFIED;
 331
 332         if ((dest_select == RNC_DEST_SUSPENDED) ||
 333             (dest_select == RNC_DEST_SUSPENDED_RESUME)) {
 334                 sci_remote_node_context_suspend(
 335                         rnc, rnc->suspend_reason,
 336                         SCI_SOFTWARE_SUSPEND_EXPECTED_EVENT);
 337
 338                 if (dest_select == RNC_DEST_SUSPENDED_RESUME)
 339                         tell_user = 0;  /* Wait until ready again. */
 340         }
 341         if (tell_user)
 342                 sci_remote_node_context_notify_user(rnc);
 343 }
 344
 345 static void sci_remote_node_context_tx_suspended_state_enter(struct sci_base_state_machine *sm)
 346 {
 347         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 348
 349         sci_remote_node_context_continue_state_transitions(rnc);
 350 }
 351
 352 static void sci_remote_node_context_tx_rx_suspended_state_enter(struct sci_base_state_machine *sm)
 353 {
 354         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 355         struct isci_remote_device *idev = rnc_to_dev(rnc);
 356         struct isci_host *ihost = idev->owning_port->owning_controller;
 357         u32 new_count = rnc->suspend_count + 1;
 358
 359         if (new_count == 0)
 360                 rnc->suspend_count = 1;
 361         else
 362                 rnc->suspend_count = new_count;
 363         smp_wmb();
 364
 365         /* Terminate outstanding requests pending abort. */
 366         sci_remote_device_abort_requests_pending_abort(idev);
 367
 368         wake_up(&ihost->eventq);
 369         sci_remote_node_context_continue_state_transitions(rnc);
 370 }
 371
 372 static void sci_remote_node_context_await_suspend_state_exit(
 373         struct sci_base_state_machine *sm)
 374 {
 375         struct sci_remote_node_context *rnc
 376                 = container_of(sm, typeof(*rnc), sm);
 377         struct isci_remote_device *idev = rnc_to_dev(rnc);
 378
 379         if (dev_is_sata(idev->domain_dev))
 380                 isci_dev_set_hang_detection_timeout(idev, 0);
 381 }
 382
 383 static const struct sci_base_state sci_remote_node_context_state_table[] = {
 384         [SCI_RNC_INITIAL] = {
 385                 .enter_state = sci_remote_node_context_initial_state_enter,
 386         },
 387         [SCI_RNC_POSTING] = {
 388                 .enter_state = sci_remote_node_context_posting_state_enter,
 389         },
 390         [SCI_RNC_INVALIDATING] = {
 391                 .enter_state = sci_remote_node_context_invalidating_state_enter,
 392         },
 393         [SCI_RNC_RESUMING] = {
 394                 .enter_state = sci_remote_node_context_resuming_state_enter,
 395         },
 396         [SCI_RNC_READY] = {
 397                 .enter_state = sci_remote_node_context_ready_state_enter,
 398         },
 399         [SCI_RNC_TX_SUSPENDED] = {
 400                 .enter_state = sci_remote_node_context_tx_suspended_state_enter,
 401         },
 402         [SCI_RNC_TX_RX_SUSPENDED] = {
 403                 .enter_state = sci_remote_node_context_tx_rx_suspended_state_enter,
 404         },
 405         [SCI_RNC_AWAIT_SUSPENSION] = {
 406                 .exit_state = sci_remote_node_context_await_suspend_state_exit,
 407         },
 408 };
 409
 410 void sci_remote_node_context_construct(struct sci_remote_node_context *rnc,
 411                                             u16 remote_node_index)
 412 {
 413         memset(rnc, 0, sizeof(struct sci_remote_node_context));
 414
 415         rnc->remote_node_index = remote_node_index;
 416         rnc->destination_state = RNC_DEST_UNSPECIFIED;
 417
 418         sci_init_sm(&rnc->sm, sci_remote_node_context_state_table, SCI_RNC_INITIAL);
 419 }
 420
 421 enum sci_status sci_remote_node_context_event_handler(struct sci_remote_node_context *sci_rnc,
 422                                                            u32 event_code)
 423 {
 424         enum scis_sds_remote_node_context_states state;
 425         u32 next_state;
 426
 427         state = sci_rnc->sm.current_state_id;
 428         switch (state) {
 429         case SCI_RNC_POSTING:
 430                 switch (scu_get_event_code(event_code)) {
 431                 case SCU_EVENT_POST_RNC_COMPLETE:
 432                         sci_change_state(&sci_rnc->sm, SCI_RNC_READY);
 433                         break;
 434                 default:
 435                         goto out;
 436                 }
 437                 break;
 438         case SCI_RNC_INVALIDATING:
 439                 if (scu_get_event_code(event_code) == SCU_EVENT_POST_RNC_INVALIDATE_COMPLETE) {
 440                         if (sci_rnc->destination_state == RNC_DEST_FINAL)
 441                                 next_state = SCI_RNC_INITIAL;
 442                         else
 443                                 next_state = SCI_RNC_POSTING;
 444                         sci_change_state(&sci_rnc->sm, next_state);
 445                 } else {
 446                         switch (scu_get_event_type(event_code)) {
 447                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
 448                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
 449                                 /* We really dont care if the hardware is going to suspend
 450                                  * the device since it's being invalidated anyway */
 451                                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 452                                         "%s: SCIC Remote Node Context 0x%p was "
 453                                         "suspended by hardware while being "
 454                                         "invalidated.\n", __func__, sci_rnc);
 455                                 break;
 456                         default:
 457                                 goto out;
 458                         }
 459                 }
 460                 break;
 461         case SCI_RNC_RESUMING:
 462                 if (scu_get_event_code(event_code) == SCU_EVENT_POST_RCN_RELEASE) {
 463                         sci_change_state(&sci_rnc->sm, SCI_RNC_READY);
 464                 } else {
 465                         switch (scu_get_event_type(event_code)) {
 466                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
 467                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
 468                                 /* We really dont care if the hardware is going to suspend
 469                                  * the device since it's being resumed anyway */
 470                                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 471                                         "%s: SCIC Remote Node Context 0x%p was "
 472                                         "suspended by hardware while being resumed.\n",
 473                                         __func__, sci_rnc);
 474                                 break;
 475                         default:
 476                                 goto out;
 477                         }
 478                 }
 479                 break;
 480         case SCI_RNC_READY:
 481                 switch (scu_get_event_type(event_code)) {
 482                 case SCU_EVENT_TL_RNC_SUSPEND_TX:
 483                         sci_change_state(&sci_rnc->sm, SCI_RNC_TX_SUSPENDED);
 484                         sci_rnc->suspend_type = scu_get_event_type(event_code);
 485                         break;
 486                 case SCU_EVENT_TL_RNC_SUSPEND_TX_RX:
 487                         sci_change_state(&sci_rnc->sm, SCI_RNC_TX_RX_SUSPENDED);
 488                         sci_rnc->suspend_type = scu_get_event_type(event_code);
 489                         break;
 490                 default:
 491                         goto out;
 492                 }
 493                 break;
 494         case SCI_RNC_AWAIT_SUSPENSION:
 495                 switch (scu_get_event_type(event_code)) {
 496                 case SCU_EVENT_TL_RNC_SUSPEND_TX:
 497                         next_state = SCI_RNC_TX_SUSPENDED;
 498                         break;
 499                 case SCU_EVENT_TL_RNC_SUSPEND_TX_RX:
 500                         next_state = SCI_RNC_TX_RX_SUSPENDED;
 501                         break;
 502                 default:
 503                         goto out;
 504                 }
 505                 if (sci_rnc->suspend_type == scu_get_event_type(event_code))
 506                         sci_change_state(&sci_rnc->sm, next_state);
 507                 break;
 508         default:
 509                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 510                          "%s: invalid state: %s\n", __func__,
 511                          rnc_state_name(state));
 512                 return SCI_FAILURE_INVALID_STATE;
 513         }
 514         return SCI_SUCCESS;
 515
 516  out:
 517         dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 518                  "%s: code: %#x state: %s\n", __func__, event_code,
 519                  rnc_state_name(state));
 520         return SCI_FAILURE;
 521
 522 }
 523
 524 enum sci_status sci_remote_node_context_destruct(struct sci_remote_node_context *sci_rnc,
 525                                                       scics_sds_remote_node_context_callback cb_fn,
 526                                                       void *cb_p)
 527 {
 528         enum scis_sds_remote_node_context_states state;
 529
 530         state = sci_rnc->sm.current_state_id;
 531         switch (state) {
 532         case SCI_RNC_INVALIDATING:
 533                 sci_remote_node_context_setup_to_destroy(sci_rnc, cb_fn, cb_p);
 534                 return SCI_SUCCESS;
 535         case SCI_RNC_POSTING:
 536         case SCI_RNC_RESUMING:
 537         case SCI_RNC_READY:
 538         case SCI_RNC_TX_SUSPENDED:
 539         case SCI_RNC_TX_RX_SUSPENDED:
 540                 sci_remote_node_context_setup_to_destroy(sci_rnc, cb_fn, cb_p);
 541                 sci_change_state(&sci_rnc->sm, SCI_RNC_INVALIDATING);
 542                 return SCI_SUCCESS;
 543         case SCI_RNC_AWAIT_SUSPENSION:
 544                 sci_remote_node_context_setup_to_destroy(sci_rnc, cb_fn, cb_p);
 545                 return SCI_SUCCESS;
 546         case SCI_RNC_INITIAL:
 547                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 548                          "%s: invalid state: %s\n", __func__,
 549                          rnc_state_name(state));
 550                 /* We have decided that the destruct request on the remote node context
 551                  * can not fail since it is either in the initial/destroyed state or is
 552                  * can be destroyed.
 553                  */
 554                 return SCI_SUCCESS;
 555         default:
 556                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 557                          "%s: invalid state %s\n", __func__,
 558                          rnc_state_name(state));
 559                 return SCI_FAILURE_INVALID_STATE;
 560         }
 561 }
 562
 563 enum sci_status sci_remote_node_context_suspend(
 564                         struct sci_remote_node_context *sci_rnc,
 565                         enum sci_remote_node_suspension_reasons suspend_reason,
 566                         u32 suspend_type)
 567 {
 568         enum scis_sds_remote_node_context_states state
 569                 = sci_rnc->sm.current_state_id;
 570         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 571         enum sci_status status = SCI_FAILURE_INVALID_STATE;
 572         enum sci_remote_node_context_destination_state dest_param =
 573                 RNC_DEST_UNSPECIFIED;
 574
 575         dev_dbg(scirdev_to_dev(idev),
 576                 "%s: current state %s, current suspend_type %x dest state %d,"
 577                         " arg suspend_reason %d, arg suspend_type %x",
 578                 __func__, rnc_state_name(state), sci_rnc->suspend_type,
 579                 sci_rnc->destination_state, suspend_reason,
 580                 suspend_type);
 581
 582         /* Disable automatic state continuations if explicitly suspending. */
 583         if ((suspend_reason == SCI_HW_SUSPEND) ||
 584             (sci_rnc->destination_state == RNC_DEST_FINAL))
 585                 dest_param = sci_rnc->destination_state;
 586
 587         switch (state) {
 588         case SCI_RNC_READY:
 589                 break;
 590         case SCI_RNC_INVALIDATING:
 591                 if (sci_rnc->destination_state == RNC_DEST_FINAL) {
 592                         dev_warn(scirdev_to_dev(idev),
 593                                  "%s: already destroying %p\n",
 594                                  __func__, sci_rnc);
 595                         return SCI_FAILURE_INVALID_STATE;
 596                 }
 597                 fallthrough;    /* and handle like SCI_RNC_POSTING */
 598         case SCI_RNC_RESUMING:
 599                 fallthrough;    /* and handle like SCI_RNC_POSTING */
 600         case SCI_RNC_POSTING:
 601                 /* Set the destination state to AWAIT - this signals the
 602                  * entry into the SCI_RNC_READY state that a suspension
 603                  * needs to be done immediately.
 604                  */
 605                 if (sci_rnc->destination_state != RNC_DEST_FINAL)
 606                         sci_rnc->destination_state = RNC_DEST_SUSPENDED;
 607                 sci_rnc->suspend_type = suspend_type;
 608                 sci_rnc->suspend_reason = suspend_reason;
 609                 return SCI_SUCCESS;
 610
 611         case SCI_RNC_TX_SUSPENDED:
 612                 if (suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX)
 613                         status = SCI_SUCCESS;
 614                 break;
 615         case SCI_RNC_TX_RX_SUSPENDED:
 616                 if (suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX_RX)
 617                         status = SCI_SUCCESS;
 618                 break;
 619         case SCI_RNC_AWAIT_SUSPENSION:
 620                 if ((sci_rnc->suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX_RX)
 621                     || (suspend_type == sci_rnc->suspend_type))
 622                         return SCI_SUCCESS;
 623                 break;
 624         default:
 625                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 626                          "%s: invalid state %s\n", __func__,
 627                          rnc_state_name(state));
 628                 return SCI_FAILURE_INVALID_STATE;
 629         }
 630         sci_rnc->destination_state = dest_param;
 631         sci_rnc->suspend_type = suspend_type;
 632         sci_rnc->suspend_reason = suspend_reason;
 633
 634         if (status == SCI_SUCCESS) { /* Already in the destination state? */
 635                 struct isci_host *ihost = idev->owning_port->owning_controller;
 636
 637                 wake_up_all(&ihost->eventq); /* Let observers look. */
 638                 return SCI_SUCCESS;
 639         }
 640         if ((suspend_reason == SCI_SW_SUSPEND_NORMAL) ||
 641             (suspend_reason == SCI_SW_SUSPEND_LINKHANG_DETECT)) {
 642
 643                 if (suspend_reason == SCI_SW_SUSPEND_LINKHANG_DETECT)
 644                         isci_dev_set_hang_detection_timeout(idev, 0x00000001);
 645
 646                 sci_remote_device_post_request(
 647                         idev, SCI_SOFTWARE_SUSPEND_CMD);
 648         }
 649         if (state != SCI_RNC_AWAIT_SUSPENSION)
 650                 sci_change_state(&sci_rnc->sm, SCI_RNC_AWAIT_SUSPENSION);
 651
 652         return SCI_SUCCESS;
 653 }
 654
 655 enum sci_status sci_remote_node_context_resume(struct sci_remote_node_context *sci_rnc,
 656                                                     scics_sds_remote_node_context_callback cb_fn,
 657                                                     void *cb_p)
 658 {
 659         enum scis_sds_remote_node_context_states state;
 660         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 661
 662         state = sci_rnc->sm.current_state_id;
 663         dev_dbg(scirdev_to_dev(idev),
 664                 "%s: state %s, cb_fn = %p, cb_p = %p; dest_state = %d; "
 665                         "dev resume path %s\n",
 666                 __func__, rnc_state_name(state), cb_fn, cb_p,
 667                 sci_rnc->destination_state,
 668                 test_bit(IDEV_ABORT_PATH_ACTIVE, &idev->flags)
 669                         ? "<abort active>" : "<normal>");
 670
 671         switch (state) {
 672         case SCI_RNC_INITIAL:
 673                 if (sci_rnc->remote_node_index == SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX)
 674                         return SCI_FAILURE_INVALID_STATE;
 675
 676                 sci_remote_node_context_setup_to_resume(sci_rnc, cb_fn, cb_p,
 677                                                         RNC_DEST_READY);
 678                 if (!test_bit(IDEV_ABORT_PATH_ACTIVE, &idev->flags)) {
 679                         sci_remote_node_context_construct_buffer(sci_rnc);
 680                         sci_change_state(&sci_rnc->sm, SCI_RNC_POSTING);
 681                 }
 682                 return SCI_SUCCESS;
 683
 684         case SCI_RNC_POSTING:
 685         case SCI_RNC_INVALIDATING:
 686         case SCI_RNC_RESUMING:
 687                 /* We are still waiting to post when a resume was
 688                  * requested.
 689                  */
 690                 switch (sci_rnc->destination_state) {
 691                 case RNC_DEST_SUSPENDED:
 692                 case RNC_DEST_SUSPENDED_RESUME:
 693                         /* Previously waiting to suspend after posting.
 694                          * Now continue onto resumption.
 695                          */
 696                         sci_remote_node_context_setup_to_resume(
 697                                 sci_rnc, cb_fn, cb_p,
 698                                 RNC_DEST_SUSPENDED_RESUME);
 699                         break;
 700                 default:
 701                         sci_remote_node_context_setup_to_resume(
 702                                 sci_rnc, cb_fn, cb_p,
 703                                 RNC_DEST_READY);
 704                         break;
 705                 }
 706                 return SCI_SUCCESS;
 707
 708         case SCI_RNC_TX_SUSPENDED:
 709         case SCI_RNC_TX_RX_SUSPENDED:
 710                 {
 711                         struct domain_device *dev = idev->domain_dev;
 712                         /* If this is an expander attached SATA device we must
 713                          * invalidate and repost the RNC since this is the only
 714                          * way to clear the TCi to NCQ tag mapping table for
 715                          * the RNi. All other device types we can just resume.
 716                          */
 717                         sci_remote_node_context_setup_to_resume(
 718                                 sci_rnc, cb_fn, cb_p, RNC_DEST_READY);
 719
 720                         if (!test_bit(IDEV_ABORT_PATH_ACTIVE, &idev->flags)) {
 721                                 if ((dev_is_sata(dev) && dev->parent) ||
 722                                     (sci_rnc->destination_state == RNC_DEST_FINAL))
 723                                         sci_change_state(&sci_rnc->sm,
 724                                                          SCI_RNC_INVALIDATING);
 725                                 else
 726                                         sci_change_state(&sci_rnc->sm,
 727                                                          SCI_RNC_RESUMING);
 728                         }
 729                 }
 730                 return SCI_SUCCESS;
 731
 732         case SCI_RNC_AWAIT_SUSPENSION:
 733                 sci_remote_node_context_setup_to_resume(
 734                         sci_rnc, cb_fn, cb_p, RNC_DEST_SUSPENDED_RESUME);
 735                 return SCI_SUCCESS;
 736         default:
 737                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 738                          "%s: invalid state %s\n", __func__,
 739                          rnc_state_name(state));
 740                 return SCI_FAILURE_INVALID_STATE;
 741         }
 742 }
 743
 744 enum sci_status sci_remote_node_context_start_io(struct sci_remote_node_context *sci_rnc,
 745                                                              struct isci_request *ireq)
 746 {
 747         enum scis_sds_remote_node_context_states state;
 748
 749         state = sci_rnc->sm.current_state_id;
 750
 751         switch (state) {
 752         case SCI_RNC_READY:
 753                 return SCI_SUCCESS;
 754         case SCI_RNC_TX_SUSPENDED:
 755         case SCI_RNC_TX_RX_SUSPENDED:
 756         case SCI_RNC_AWAIT_SUSPENSION:
 757                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 758                          "%s: invalid state %s\n", __func__,
 759                          rnc_state_name(state));
 760                 return SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED;
 761         default:
 762                 dev_dbg(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 763                         "%s: invalid state %s\n", __func__,
 764                         rnc_state_name(state));
 765                 return SCI_FAILURE_INVALID_STATE;
 766         }
 767 }
 768
 769 enum sci_status sci_remote_node_context_start_task(
 770         struct sci_remote_node_context *sci_rnc,
 771         struct isci_request *ireq,
 772         scics_sds_remote_node_context_callback cb_fn,
 773         void *cb_p)
 774 {
 775         enum sci_status status = sci_remote_node_context_resume(sci_rnc,
 776                                                                 cb_fn, cb_p);
 777         if (status != SCI_SUCCESS)
 778                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 779                         "%s: resume failed: %d\n", __func__, status);
 780         return status;
 781 }
 782
 783 int sci_remote_node_context_is_safe_to_abort(
 784         struct sci_remote_node_context *sci_rnc)
 785 {
 786         enum scis_sds_remote_node_context_states state;
 787
 788         state = sci_rnc->sm.current_state_id;
 789         switch (state) {
 790         case SCI_RNC_INVALIDATING:
 791         case SCI_RNC_TX_RX_SUSPENDED:
 792                 return 1;
 793         case SCI_RNC_POSTING:
 794         case SCI_RNC_RESUMING:
 795         case SCI_RNC_READY:
 796         case SCI_RNC_TX_SUSPENDED:
 797         case SCI_RNC_AWAIT_SUSPENSION:
 798         case SCI_RNC_INITIAL:
 799                 return 0;
 800         default:
 801                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 802                          "%s: invalid state %d\n", __func__, state);
 803                 return 0;
 804         }
 805 }