drivers/scsi/isci/remote_node_context.c

   1 /*
   2  * This file is provided under a dual BSD/GPLv2 license.  When using or
   3  * redistributing this file, you may do so under either license.
   4  *
   5  * GPL LICENSE SUMMARY
   6  *
   7  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of version 2 of the GNU General Public License as
  11  * published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  21  * The full GNU General Public License is included in this distribution
  22  * in the file called LICENSE.GPL.
  23  *
  24  * BSD LICENSE
  25  *
  26  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
  27  * All rights reserved.
  28  *
  29  * Redistribution and use in source and binary forms, with or without
  30  * modification, are permitted provided that the following conditions
  31  * are met:
  32  *
  33  *   * Redistributions of source code must retain the above copyright
  34  *     notice, this list of conditions and the following disclaimer.
  35  *   * Redistributions in binary form must reproduce the above copyright
  36  *     notice, this list of conditions and the following disclaimer in
  37  *     the documentation and/or other materials provided with the
  38  *     distribution.
  39  *   * Neither the name of Intel Corporation nor the names of its
  40  *     contributors may be used to endorse or promote products derived
  41  *     from this software without specific prior written permission.
  42  *
  43  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  44  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  45  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  46  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  47  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  48  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  49  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  50  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  51  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  52  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  53  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  54  */
  55 #include <scsi/sas_ata.h>
  56 #include "host.h"
  57 #include "isci.h"
  58 #include "remote_device.h"
  59 #include "remote_node_context.h"
  60 #include "scu_event_codes.h"
  61 #include "scu_task_context.h"
  62
  63 #undef C
  64 #define C(a) (#a)
  65 const char *rnc_state_name(enum scis_sds_remote_node_context_states state)
  66 {
  67         static const char * const strings[] = RNC_STATES;
  68
  69         return strings[state];
  70 }
  71 #undef C
  72
  73 /**
  74  *
  75  * @sci_rnc: The state of the remote node context object to check.
  76  *
  77  * This method will return true if the remote node context is in a READY state
  78  * otherwise it will return false bool true if the remote node context is in
  79  * the ready state. false if the remote node context is not in the ready state.
  80  */
  81 bool sci_remote_node_context_is_ready(
  82         struct sci_remote_node_context *sci_rnc)
  83 {
  84         u32 current_state = sci_rnc->sm.current_state_id;
  85
  86         if (current_state == SCI_RNC_READY) {
  87                 return true;
  88         }
  89
  90         return false;
  91 }
  92
  93 bool sci_remote_node_context_is_suspended(struct sci_remote_node_context *sci_rnc)
  94 {
  95         u32 current_state = sci_rnc->sm.current_state_id;
  96
  97         if (current_state == SCI_RNC_TX_RX_SUSPENDED)
  98                 return true;
  99         return false;
 100 }
 101
 102 static union scu_remote_node_context *sci_rnc_by_id(struct isci_host *ihost, u16 id)
 103 {
 104         if (id < ihost->remote_node_entries &&
 105             ihost->device_table[id])
 106                 return &ihost->remote_node_context_table[id];
 107
 108         return NULL;
 109 }
 110
 111 static void sci_remote_node_context_construct_buffer(struct sci_remote_node_context *sci_rnc)
 112 {
 113         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 114         struct domain_device *dev = idev->domain_dev;
 115         int rni = sci_rnc->remote_node_index;
 116         union scu_remote_node_context *rnc;
 117         struct isci_host *ihost;
 118         __le64 sas_addr;
 119
 120         ihost = idev->owning_port->owning_controller;
 121         rnc = sci_rnc_by_id(ihost, rni);
 122
 123         memset(rnc, 0, sizeof(union scu_remote_node_context)
 124                 * sci_remote_device_node_count(idev));
 125
 126         rnc->ssp.remote_node_index = rni;
 127         rnc->ssp.remote_node_port_width = idev->device_port_width;
 128         rnc->ssp.logical_port_index = idev->owning_port->physical_port_index;
 129
 130         /* sas address is __be64, context ram format is __le64 */
 131         sas_addr = cpu_to_le64(SAS_ADDR(dev->sas_addr));
 132         rnc->ssp.remote_sas_address_hi = upper_32_bits(sas_addr);
 133         rnc->ssp.remote_sas_address_lo = lower_32_bits(sas_addr);
 134
 135         rnc->ssp.nexus_loss_timer_enable = true;
 136         rnc->ssp.check_bit               = false;
 137         rnc->ssp.is_valid                = false;
 138         rnc->ssp.is_remote_node_context  = true;
 139         rnc->ssp.function_number         = 0;
 140
 141         rnc->ssp.arbitration_wait_time = 0;
 142
 143         if (dev_is_sata(dev)) {
 144                 rnc->ssp.connection_occupancy_timeout =
 145                         ihost->user_parameters.stp_max_occupancy_timeout;
 146                 rnc->ssp.connection_inactivity_timeout =
 147                         ihost->user_parameters.stp_inactivity_timeout;
 148         } else {
 149                 rnc->ssp.connection_occupancy_timeout  =
 150                         ihost->user_parameters.ssp_max_occupancy_timeout;
 151                 rnc->ssp.connection_inactivity_timeout =
 152                         ihost->user_parameters.ssp_inactivity_timeout;
 153         }
 154
 155         rnc->ssp.initial_arbitration_wait_time = 0;
 156
 157         /* Open Address Frame Parameters */
 158         rnc->ssp.oaf_connection_rate = idev->connection_rate;
 159         rnc->ssp.oaf_features = 0;
 160         rnc->ssp.oaf_source_zone_group = 0;
 161         rnc->ssp.oaf_more_compatibility_features = 0;
 162 }
 163
 164 static void sci_remote_node_context_save_cbparams(
 165         struct sci_remote_node_context *sci_rnc,
 166         scics_sds_remote_node_context_callback callback,
 167         void *callback_parameter)
 168 {
 169         sci_rnc->user_callback = callback;
 170         sci_rnc->user_cookie   = callback_parameter;
 171 }
 172 /**
 173  *
 174  * @sci_rnc:
 175  * @callback:
 176  * @callback_parameter:
 177  *
 178  * This method will setup the remote node context object so it will transition
 179  * to its ready state.  If the remote node context is already setup to
 180  * transition to its final state then this function does nothing. none
 181  */
 182 static void sci_remote_node_context_setup_to_resume(
 183         struct sci_remote_node_context *sci_rnc,
 184         scics_sds_remote_node_context_callback callback,
 185         void *callback_parameter,
 186         enum sci_remote_node_context_destination_state dest_param)
 187 {
 188         if (sci_rnc->destination_state != RNC_DEST_FINAL) {
 189                 sci_rnc->destination_state = dest_param;
 190                 if (callback != NULL)
 191                         sci_remote_node_context_save_cbparams(
 192                                 sci_rnc, callback, callback_parameter);
 193         }
 194 }
 195
 196 static void sci_remote_node_context_setup_to_destroy(
 197         struct sci_remote_node_context *sci_rnc,
 198         scics_sds_remote_node_context_callback callback,
 199         void *callback_parameter)
 200 {
 201         sci_rnc->destination_state = RNC_DEST_FINAL;
 202         sci_rnc->user_callback     = callback;
 203         sci_rnc->user_cookie       = callback_parameter;
 204 }
 205
 206 /**
 207  *
 208  *
 209  * This method just calls the user callback function and then resets the
 210  * callback.
 211  */
 212 static void sci_remote_node_context_notify_user(
 213         struct sci_remote_node_context *rnc)
 214 {
 215         if (rnc->user_callback != NULL) {
 216                 (*rnc->user_callback)(rnc->user_cookie);
 217
 218                 rnc->user_callback = NULL;
 219                 rnc->user_cookie = NULL;
 220         }
 221 }
 222
 223 static void sci_remote_node_context_continue_state_transitions(struct sci_remote_node_context *rnc)
 224 {
 225         if ((rnc->destination_state == RNC_DEST_READY) ||
 226             (rnc->destination_state == RNC_DEST_SUSPENDED_RESUME)) {
 227                 rnc->destination_state = RNC_DEST_READY;
 228                 sci_remote_node_context_resume(rnc, rnc->user_callback,
 229                                                     rnc->user_cookie);
 230         } else
 231                 rnc->destination_state = RNC_DEST_UNSPECIFIED;
 232 }
 233
 234 static void sci_remote_node_context_validate_context_buffer(struct sci_remote_node_context *sci_rnc)
 235 {
 236         union scu_remote_node_context *rnc_buffer;
 237         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 238         struct domain_device *dev = idev->domain_dev;
 239         struct isci_host *ihost = idev->owning_port->owning_controller;
 240
 241         rnc_buffer = sci_rnc_by_id(ihost, sci_rnc->remote_node_index);
 242
 243         rnc_buffer->ssp.is_valid = true;
 244
 245         if (dev_is_sata(dev) && dev->parent) {
 246                 sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_96);
 247         } else {
 248                 sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_32);
 249
 250                 if (!dev->parent)
 251                         sci_port_setup_transports(idev->owning_port,
 252                                                   sci_rnc->remote_node_index);
 253         }
 254 }
 255
 256 static void sci_remote_node_context_invalidate_context_buffer(struct sci_remote_node_context *sci_rnc)
 257 {
 258         union scu_remote_node_context *rnc_buffer;
 259         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 260         struct isci_host *ihost = idev->owning_port->owning_controller;
 261
 262         rnc_buffer = sci_rnc_by_id(ihost, sci_rnc->remote_node_index);
 263
 264         rnc_buffer->ssp.is_valid = false;
 265
 266         sci_remote_device_post_request(rnc_to_dev(sci_rnc),
 267                                        SCU_CONTEXT_COMMAND_POST_RNC_INVALIDATE);
 268 }
 269
 270 static void sci_remote_node_context_initial_state_enter(struct sci_base_state_machine *sm)
 271 {
 272         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 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 }
 282
 283 static void sci_remote_node_context_posting_state_enter(struct sci_base_state_machine *sm)
 284 {
 285         struct sci_remote_node_context *sci_rnc = container_of(sm, typeof(*sci_rnc), sm);
 286
 287         sci_remote_node_context_validate_context_buffer(sci_rnc);
 288 }
 289
 290 static void sci_remote_node_context_invalidating_state_enter(struct sci_base_state_machine *sm)
 291 {
 292         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 293
 294         /* Terminate all outstanding requests. */
 295         sci_remote_device_terminate_requests(rnc_to_dev(rnc));
 296         sci_remote_node_context_invalidate_context_buffer(rnc);
 297 }
 298
 299 static void sci_remote_node_context_resuming_state_enter(struct sci_base_state_machine *sm)
 300 {
 301         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 302         struct isci_remote_device *idev;
 303         struct domain_device *dev;
 304
 305         idev = rnc_to_dev(rnc);
 306         dev = idev->domain_dev;
 307
 308         /*
 309          * For direct attached SATA devices we need to clear the TLCR
 310          * NCQ to TCi tag mapping on the phy and in cases where we
 311          * resume because of a target reset we also need to update
 312          * the STPTLDARNI register with the RNi of the device
 313          */
 314         if (dev_is_sata(dev) && !dev->parent)
 315                 sci_port_setup_transports(idev->owning_port, rnc->remote_node_index);
 316
 317         sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_RESUME);
 318 }
 319
 320 static void sci_remote_node_context_ready_state_enter(struct sci_base_state_machine *sm)
 321 {
 322         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 323         enum sci_remote_node_context_destination_state dest_select;
 324         int tell_user = 1;
 325
 326         dest_select = rnc->destination_state;
 327         rnc->destination_state = RNC_DEST_UNSPECIFIED;
 328
 329         if ((dest_select == RNC_DEST_SUSPENDED) ||
 330             (dest_select == RNC_DEST_SUSPENDED_RESUME)) {
 331                 sci_remote_node_context_suspend(
 332                         rnc, rnc->suspend_reason,
 333                         SCI_SOFTWARE_SUSPEND_EXPECTED_EVENT);
 334
 335                 if (dest_select == RNC_DEST_SUSPENDED_RESUME)
 336                         tell_user = 0;  /* Wait until ready again. */
 337         }
 338         if (tell_user)
 339                 sci_remote_node_context_notify_user(rnc);
 340 }
 341
 342 static void sci_remote_node_context_tx_suspended_state_enter(struct sci_base_state_machine *sm)
 343 {
 344         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 345
 346         sci_remote_node_context_continue_state_transitions(rnc);
 347 }
 348
 349 static void sci_remote_node_context_tx_rx_suspended_state_enter(struct sci_base_state_machine *sm)
 350 {
 351         struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 352         struct isci_remote_device *idev = rnc_to_dev(rnc);
 353         struct isci_host *ihost = idev->owning_port->owning_controller;
 354         u32 new_count = rnc->suspend_count + 1;
 355
 356         if (new_count == 0)
 357                 rnc->suspend_count = 1;
 358         else
 359                 rnc->suspend_count = new_count;
 360         smp_wmb();
 361
 362         /* Terminate outstanding requests pending abort. */
 363         sci_remote_device_abort_requests_pending_abort(idev);
 364
 365         wake_up(&ihost->eventq);
 366         sci_remote_node_context_continue_state_transitions(rnc);
 367 }
 368
 369 static void sci_remote_node_context_await_suspend_state_exit(
 370         struct sci_base_state_machine *sm)
 371 {
 372         struct sci_remote_node_context *rnc
 373                 = container_of(sm, typeof(*rnc), sm);
 374         struct isci_remote_device *idev = rnc_to_dev(rnc);
 375
 376         if (dev_is_sata(idev->domain_dev))
 377                 isci_dev_set_hang_detection_timeout(idev, 0);
 378 }
 379
 380 static const struct sci_base_state sci_remote_node_context_state_table[] = {
 381         [SCI_RNC_INITIAL] = {
 382                 .enter_state = sci_remote_node_context_initial_state_enter,
 383         },
 384         [SCI_RNC_POSTING] = {
 385                 .enter_state = sci_remote_node_context_posting_state_enter,
 386         },
 387         [SCI_RNC_INVALIDATING] = {
 388                 .enter_state = sci_remote_node_context_invalidating_state_enter,
 389         },
 390         [SCI_RNC_RESUMING] = {
 391                 .enter_state = sci_remote_node_context_resuming_state_enter,
 392         },
 393         [SCI_RNC_READY] = {
 394                 .enter_state = sci_remote_node_context_ready_state_enter,
 395         },
 396         [SCI_RNC_TX_SUSPENDED] = {
 397                 .enter_state = sci_remote_node_context_tx_suspended_state_enter,
 398         },
 399         [SCI_RNC_TX_RX_SUSPENDED] = {
 400                 .enter_state = sci_remote_node_context_tx_rx_suspended_state_enter,
 401         },
 402         [SCI_RNC_AWAIT_SUSPENSION] = {
 403                 .exit_state = sci_remote_node_context_await_suspend_state_exit,
 404         },
 405 };
 406
 407 void sci_remote_node_context_construct(struct sci_remote_node_context *rnc,
 408                                             u16 remote_node_index)
 409 {
 410         memset(rnc, 0, sizeof(struct sci_remote_node_context));
 411
 412         rnc->remote_node_index = remote_node_index;
 413         rnc->destination_state = RNC_DEST_UNSPECIFIED;
 414
 415         sci_init_sm(&rnc->sm, sci_remote_node_context_state_table, SCI_RNC_INITIAL);
 416 }
 417
 418 enum sci_status sci_remote_node_context_event_handler(struct sci_remote_node_context *sci_rnc,
 419                                                            u32 event_code)
 420 {
 421         enum scis_sds_remote_node_context_states state;
 422         u32 next_state;
 423
 424         state = sci_rnc->sm.current_state_id;
 425         switch (state) {
 426         case SCI_RNC_POSTING:
 427                 switch (scu_get_event_code(event_code)) {
 428                 case SCU_EVENT_POST_RNC_COMPLETE:
 429                         sci_change_state(&sci_rnc->sm, SCI_RNC_READY);
 430                         break;
 431                 default:
 432                         goto out;
 433                 }
 434                 break;
 435         case SCI_RNC_INVALIDATING:
 436                 if (scu_get_event_code(event_code) == SCU_EVENT_POST_RNC_INVALIDATE_COMPLETE) {
 437                         if (sci_rnc->destination_state == RNC_DEST_FINAL)
 438                                 next_state = SCI_RNC_INITIAL;
 439                         else
 440                                 next_state = SCI_RNC_POSTING;
 441                         sci_change_state(&sci_rnc->sm, next_state);
 442                 } else {
 443                         switch (scu_get_event_type(event_code)) {
 444                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
 445                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
 446                                 /* We really dont care if the hardware is going to suspend
 447                                  * the device since it's being invalidated anyway */
 448                                 dev_dbg(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 449                                         "%s: SCIC Remote Node Context 0x%p was "
 450                                         "suspeneded by hardware while being "
 451                                         "invalidated.\n", __func__, sci_rnc);
 452                                 break;
 453                         default:
 454                                 goto out;
 455                         }
 456                 }
 457                 break;
 458         case SCI_RNC_RESUMING:
 459                 if (scu_get_event_code(event_code) == SCU_EVENT_POST_RCN_RELEASE) {
 460                         sci_change_state(&sci_rnc->sm, SCI_RNC_READY);
 461                 } else {
 462                         switch (scu_get_event_type(event_code)) {
 463                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
 464                         case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
 465                                 /* We really dont care if the hardware is going to suspend
 466                                  * the device since it's being resumed anyway */
 467                                 dev_dbg(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 468                                         "%s: SCIC Remote Node Context 0x%p was "
 469                                         "suspeneded by hardware while being resumed.\n",
 470                                         __func__, sci_rnc);
 471                                 break;
 472                         default:
 473                                 goto out;
 474                         }
 475                 }
 476                 break;
 477         case SCI_RNC_READY:
 478                 switch (scu_get_event_type(event_code)) {
 479                 case SCU_EVENT_TL_RNC_SUSPEND_TX:
 480                         sci_change_state(&sci_rnc->sm, SCI_RNC_TX_SUSPENDED);
 481                         sci_rnc->suspend_type = scu_get_event_type(event_code);
 482                         break;
 483                 case SCU_EVENT_TL_RNC_SUSPEND_TX_RX:
 484                         sci_change_state(&sci_rnc->sm, SCI_RNC_TX_RX_SUSPENDED);
 485                         sci_rnc->suspend_type = scu_get_event_type(event_code);
 486                         break;
 487                 default:
 488                         goto out;
 489                 }
 490                 break;
 491         case SCI_RNC_AWAIT_SUSPENSION:
 492                 switch (scu_get_event_type(event_code)) {
 493                 case SCU_EVENT_TL_RNC_SUSPEND_TX:
 494                         next_state = SCI_RNC_TX_SUSPENDED;
 495                         break;
 496                 case SCU_EVENT_TL_RNC_SUSPEND_TX_RX:
 497                         next_state = SCI_RNC_TX_RX_SUSPENDED;
 498                         break;
 499                 default:
 500                         goto out;
 501                 }
 502                 if (sci_rnc->suspend_type == scu_get_event_type(event_code))
 503                         sci_change_state(&sci_rnc->sm, next_state);
 504                 break;
 505         default:
 506                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 507                          "%s: invalid state: %s\n", __func__,
 508                          rnc_state_name(state));
 509                 return SCI_FAILURE_INVALID_STATE;
 510         }
 511         return SCI_SUCCESS;
 512
 513  out:
 514         dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 515                  "%s: code: %#x state: %s\n", __func__, event_code,
 516                  rnc_state_name(state));
 517         return SCI_FAILURE;
 518
 519 }
 520
 521 enum sci_status sci_remote_node_context_destruct(struct sci_remote_node_context *sci_rnc,
 522                                                       scics_sds_remote_node_context_callback cb_fn,
 523                                                       void *cb_p)
 524 {
 525         enum scis_sds_remote_node_context_states state;
 526
 527         state = sci_rnc->sm.current_state_id;
 528         switch (state) {
 529         case SCI_RNC_INVALIDATING:
 530                 sci_remote_node_context_setup_to_destroy(sci_rnc, cb_fn, cb_p);
 531                 return SCI_SUCCESS;
 532         case SCI_RNC_POSTING:
 533         case SCI_RNC_RESUMING:
 534         case SCI_RNC_READY:
 535         case SCI_RNC_TX_SUSPENDED:
 536         case SCI_RNC_TX_RX_SUSPENDED:
 537         case SCI_RNC_AWAIT_SUSPENSION:
 538                 sci_remote_node_context_setup_to_destroy(sci_rnc, cb_fn, cb_p);
 539                 sci_change_state(&sci_rnc->sm, SCI_RNC_INVALIDATING);
 540                 return SCI_SUCCESS;
 541         case SCI_RNC_INITIAL:
 542                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 543                          "%s: invalid state: %s\n", __func__,
 544                          rnc_state_name(state));
 545                 /* We have decided that the destruct request on the remote node context
 546                  * can not fail since it is either in the initial/destroyed state or is
 547                  * can be destroyed.
 548                  */
 549                 return SCI_SUCCESS;
 550         default:
 551                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 552                          "%s: invalid state %s\n", __func__,
 553                          rnc_state_name(state));
 554                 return SCI_FAILURE_INVALID_STATE;
 555         }
 556 }
 557
 558 enum sci_status sci_remote_node_context_suspend(
 559                         struct sci_remote_node_context *sci_rnc,
 560                         enum sci_remote_node_suspension_reasons suspend_reason,
 561                         u32 suspend_type)
 562 {
 563         enum scis_sds_remote_node_context_states state
 564                 = sci_rnc->sm.current_state_id;
 565         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 566         enum sci_status status = SCI_FAILURE_INVALID_STATE;
 567         enum sci_remote_node_context_destination_state dest_param =
 568                 RNC_DEST_UNSPECIFIED;
 569
 570         dev_dbg(scirdev_to_dev(idev),
 571                 "%s: current state %d, current suspend_type %x dest state %d,"
 572                         " arg suspend_reason %d, arg suspend_type %x",
 573                 __func__, state, sci_rnc->suspend_type,
 574                 sci_rnc->destination_state, suspend_reason,
 575                 suspend_type);
 576
 577         /* Disable automatic state continuations if explicitly suspending. */
 578         if ((suspend_reason == SCI_HW_SUSPEND) ||
 579             (sci_rnc->destination_state == RNC_DEST_FINAL))
 580                 dest_param = sci_rnc->destination_state;
 581
 582         switch (state) {
 583         case SCI_RNC_READY:
 584                 break;
 585         case SCI_RNC_INVALIDATING:
 586                 if (sci_rnc->destination_state == RNC_DEST_FINAL) {
 587                         dev_warn(scirdev_to_dev(idev),
 588                                  "%s: already destroying %p\n",
 589                                  __func__, sci_rnc);
 590                         return SCI_FAILURE_INVALID_STATE;
 591                 }
 592                 /* Fall through and handle like SCI_RNC_POSTING */
 593         case SCI_RNC_RESUMING:
 594                 /* Fall through and handle like SCI_RNC_POSTING */
 595         case SCI_RNC_POSTING:
 596                 /* Set the destination state to AWAIT - this signals the
 597                  * entry into the SCI_RNC_READY state that a suspension
 598                  * needs to be done immediately.
 599                  */
 600                 sci_rnc->destination_state = RNC_DEST_SUSPENDED;
 601                 sci_rnc->suspend_type = suspend_type;
 602                 sci_rnc->suspend_reason = suspend_reason;
 603                 return SCI_SUCCESS;
 604
 605         case SCI_RNC_TX_SUSPENDED:
 606                 if (suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX)
 607                         status = SCI_SUCCESS;
 608                 break;
 609         case SCI_RNC_TX_RX_SUSPENDED:
 610                 if (suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX_RX)
 611                         status = SCI_SUCCESS;
 612                 break;
 613         case SCI_RNC_AWAIT_SUSPENSION:
 614                 if ((sci_rnc->suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX_RX)
 615                     || (suspend_type == sci_rnc->suspend_type))
 616                         return SCI_SUCCESS;
 617                 break;
 618         default:
 619                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 620                          "%s: invalid state %s\n", __func__,
 621                          rnc_state_name(state));
 622                 return SCI_FAILURE_INVALID_STATE;
 623         }
 624         sci_rnc->destination_state = dest_param;
 625         sci_rnc->suspend_type = suspend_type;
 626         sci_rnc->suspend_reason = suspend_reason;
 627
 628         if (status == SCI_SUCCESS) { /* Already in the destination state? */
 629                 struct isci_host *ihost = idev->owning_port->owning_controller;
 630
 631                 wake_up_all(&ihost->eventq); /* Let observers look. */
 632                 return SCI_SUCCESS;
 633         }
 634         if ((suspend_reason == SCI_SW_SUSPEND_NORMAL) ||
 635             (suspend_reason == SCI_SW_SUSPEND_LINKHANG_DETECT)) {
 636
 637                 if (suspend_reason == SCI_SW_SUSPEND_LINKHANG_DETECT)
 638                         isci_dev_set_hang_detection_timeout(idev, 0x00000001);
 639
 640                 sci_remote_device_post_request(
 641                         idev, SCI_SOFTWARE_SUSPEND_CMD);
 642         }
 643         if (state != SCI_RNC_AWAIT_SUSPENSION)
 644                 sci_change_state(&sci_rnc->sm, SCI_RNC_AWAIT_SUSPENSION);
 645
 646         return SCI_SUCCESS;
 647 }
 648
 649 enum sci_status sci_remote_node_context_resume(struct sci_remote_node_context *sci_rnc,
 650                                                     scics_sds_remote_node_context_callback cb_fn,
 651                                                     void *cb_p)
 652 {
 653         enum scis_sds_remote_node_context_states state;
 654         struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 655
 656         state = sci_rnc->sm.current_state_id;
 657         dev_dbg(scirdev_to_dev(idev),
 658                 "%s: state %s, cb_fn = %p, cb_p = %p; dest_state = %d; "
 659                         "dev resume path %s\n",
 660                 __func__, rnc_state_name(state), cb_fn, cb_p,
 661                 sci_rnc->destination_state,
 662                 test_bit(IDEV_ABORT_PATH_ACTIVE, &idev->flags)
 663                         ? "<abort active>" : "<normal>");
 664
 665         switch (state) {
 666         case SCI_RNC_INITIAL:
 667                 if (sci_rnc->remote_node_index == SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX)
 668                         return SCI_FAILURE_INVALID_STATE;
 669
 670                 if (test_bit(IDEV_ABORT_PATH_ACTIVE, &idev->flags))
 671                         sci_remote_node_context_save_cbparams(sci_rnc, cb_fn,
 672                                                               cb_p);
 673                 else {
 674                         sci_remote_node_context_setup_to_resume(sci_rnc, cb_fn,
 675                                                         cb_p, RNC_DEST_READY);
 676                         sci_remote_node_context_construct_buffer(sci_rnc);
 677                         sci_change_state(&sci_rnc->sm, SCI_RNC_POSTING);
 678                 }
 679                 return SCI_SUCCESS;
 680
 681         case SCI_RNC_POSTING:
 682         case SCI_RNC_INVALIDATING:
 683         case SCI_RNC_RESUMING:
 684                 if (test_bit(IDEV_ABORT_PATH_ACTIVE, &idev->flags))
 685                         sci_remote_node_context_save_cbparams(sci_rnc, cb_fn,
 686                                                               cb_p);
 687                 else {
 688                         /* We are still waiting to post when a resume was
 689                          * requested.
 690                          */
 691                         switch (sci_rnc->destination_state) {
 692                         case RNC_DEST_SUSPENDED:
 693                         case RNC_DEST_SUSPENDED_RESUME:
 694                                 /* Previously waiting to suspend after posting.
 695                                  * Now continue onto resumption.
 696                                  */
 697                                 sci_remote_node_context_setup_to_resume(
 698                                         sci_rnc, cb_fn, cb_p,
 699                                         RNC_DEST_SUSPENDED_RESUME);
 700                                 break;
 701                         default:
 702                                 sci_remote_node_context_setup_to_resume(
 703                                         sci_rnc, cb_fn, cb_p,
 704                                         RNC_DEST_READY);
 705                                 break;
 706                         }
 707                 }
 708                 return SCI_SUCCESS;
 709
 710         case SCI_RNC_TX_SUSPENDED:
 711         case SCI_RNC_TX_RX_SUSPENDED:
 712                 if (test_bit(IDEV_ABORT_PATH_ACTIVE, &idev->flags))
 713                         sci_remote_node_context_save_cbparams(sci_rnc, cb_fn,
 714                                                               cb_p);
 715                 else {
 716                         struct domain_device *dev = idev->domain_dev;
 717                         /* If this is an expander attached SATA device we must
 718                          * invalidate and repost the RNC since this is the only
 719                          * way to clear the TCi to NCQ tag mapping table for
 720                          * the RNi. All other device types we can just resume.
 721                          */
 722                         sci_remote_node_context_setup_to_resume(
 723                                 sci_rnc, cb_fn, cb_p, RNC_DEST_READY);
 724
 725                         if (dev_is_sata(dev) && dev->parent)
 726                                 sci_change_state(&sci_rnc->sm,
 727                                                  SCI_RNC_INVALIDATING);
 728                         else
 729                                 sci_change_state(&sci_rnc->sm,
 730                                                  SCI_RNC_RESUMING);
 731                 }
 732                 return SCI_SUCCESS;
 733
 734         case SCI_RNC_AWAIT_SUSPENSION:
 735                 if (test_bit(IDEV_ABORT_PATH_ACTIVE, &idev->flags))
 736                         sci_remote_node_context_save_cbparams(sci_rnc, cb_fn,
 737                                                               cb_p);
 738                 else
 739                         sci_remote_node_context_setup_to_resume(
 740                                 sci_rnc, cb_fn, cb_p,
 741                                 RNC_DEST_SUSPENDED_RESUME);
 742                 return SCI_SUCCESS;
 743         default:
 744                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 745                          "%s: invalid state %s\n", __func__,
 746                          rnc_state_name(state));
 747                 return SCI_FAILURE_INVALID_STATE;
 748         }
 749 }
 750
 751 enum sci_status sci_remote_node_context_start_io(struct sci_remote_node_context *sci_rnc,
 752                                                              struct isci_request *ireq)
 753 {
 754         enum scis_sds_remote_node_context_states state;
 755
 756         state = sci_rnc->sm.current_state_id;
 757
 758         switch (state) {
 759         case SCI_RNC_READY:
 760                 return SCI_SUCCESS;
 761         case SCI_RNC_TX_SUSPENDED:
 762         case SCI_RNC_TX_RX_SUSPENDED:
 763         case SCI_RNC_AWAIT_SUSPENSION:
 764                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 765                          "%s: invalid state %s\n", __func__,
 766                          rnc_state_name(state));
 767                 return SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED;
 768         default:
 769                 dev_dbg(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 770                         "%s: invalid state %s\n", __func__,
 771                         rnc_state_name(state));
 772                 return SCI_FAILURE_INVALID_STATE;
 773         }
 774 }
 775
 776 enum sci_status sci_remote_node_context_start_task(
 777         struct sci_remote_node_context *sci_rnc,
 778         struct isci_request *ireq,
 779         scics_sds_remote_node_context_callback cb_fn,
 780         void *cb_p)
 781 {
 782         enum sci_status status = sci_remote_node_context_resume(sci_rnc,
 783                                                                 cb_fn, cb_p);
 784         if (status != SCI_SUCCESS)
 785                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 786                         "%s: resume failed: %d\n", __func__, status);
 787         return status;
 788 }
 789
 790 int sci_remote_node_context_is_safe_to_abort(
 791         struct sci_remote_node_context *sci_rnc)
 792 {
 793         enum scis_sds_remote_node_context_states state;
 794
 795         state = sci_rnc->sm.current_state_id;
 796         switch (state) {
 797         case SCI_RNC_INVALIDATING:
 798         case SCI_RNC_TX_RX_SUSPENDED:
 799                 return 1;
 800         case SCI_RNC_POSTING:
 801         case SCI_RNC_RESUMING:
 802         case SCI_RNC_READY:
 803         case SCI_RNC_TX_SUSPENDED:
 804         case SCI_RNC_AWAIT_SUSPENSION:
 805         case SCI_RNC_INITIAL:
 806                 return 0;
 807         default:
 808                 dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 809                          "%s: invalid state %d\n", __func__, state);
 810                 return 0;
 811         }
 812 }