drivers/misc/mic/scif/scif_main.c

   1 /*
   2  * Intel MIC Platform Software Stack (MPSS)
   3  *
   4  * Copyright(c) 2014 Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License, version 2, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13  * General Public License for more details.
  14  *
  15  * Intel SCIF driver.
  16  *
  17  */
  18 #include <linux/module.h>
  19 #include <linux/idr.h>
  20
  21 #include <linux/mic_common.h>
  22 #include "../common/mic_dev.h"
  23 #include "../bus/scif_bus.h"
  24 #include "scif_peer_bus.h"
  25 #include "scif_main.h"
  26 #include "scif_map.h"
  27
  28 struct scif_info scif_info = {
  29         .mdev = {
  30                 .minor = MISC_DYNAMIC_MINOR,
  31                 .name = "scif",
  32                 .fops = &scif_fops,
  33         }
  34 };
  35
  36 struct scif_dev *scif_dev;
  37 static atomic_t g_loopb_cnt;
  38
  39 /* Runs in the context of intr_wq */
  40 static void scif_intr_bh_handler(struct work_struct *work)
  41 {
  42         struct scif_dev *scifdev =
  43                         container_of(work, struct scif_dev, intr_bh);
  44
  45         if (scifdev_self(scifdev))
  46                 scif_loopb_msg_handler(scifdev, scifdev->qpairs);
  47         else
  48                 scif_nodeqp_intrhandler(scifdev, scifdev->qpairs);
  49 }
  50
  51 int scif_setup_intr_wq(struct scif_dev *scifdev)
  52 {
  53         if (!scifdev->intr_wq) {
  54                 snprintf(scifdev->intr_wqname, sizeof(scifdev->intr_wqname),
  55                          "SCIF INTR %d", scifdev->node);
  56                 scifdev->intr_wq =
  57                         alloc_ordered_workqueue(scifdev->intr_wqname, 0);
  58                 if (!scifdev->intr_wq)
  59                         return -ENOMEM;
  60                 INIT_WORK(&scifdev->intr_bh, scif_intr_bh_handler);
  61         }
  62         return 0;
  63 }
  64
  65 void scif_destroy_intr_wq(struct scif_dev *scifdev)
  66 {
  67         if (scifdev->intr_wq) {
  68                 destroy_workqueue(scifdev->intr_wq);
  69                 scifdev->intr_wq = NULL;
  70         }
  71 }
  72
  73 irqreturn_t scif_intr_handler(int irq, void *data)
  74 {
  75         struct scif_dev *scifdev = data;
  76         struct scif_hw_dev *sdev = scifdev->sdev;
  77
  78         sdev->hw_ops->ack_interrupt(sdev, scifdev->db);
  79         queue_work(scifdev->intr_wq, &scifdev->intr_bh);
  80         return IRQ_HANDLED;
  81 }
  82
  83 static int scif_peer_probe(struct scif_peer_dev *spdev)
  84 {
  85         struct scif_dev *scifdev = &scif_dev[spdev->dnode];
  86
  87         mutex_lock(&scif_info.conflock);
  88         scif_info.total++;
  89         scif_info.maxid = max_t(u32, spdev->dnode, scif_info.maxid);
  90         mutex_unlock(&scif_info.conflock);
  91         rcu_assign_pointer(scifdev->spdev, spdev);
  92
  93         /* In the future SCIF kernel client devices will be added here */
  94         return 0;
  95 }
  96
  97 static void scif_peer_remove(struct scif_peer_dev *spdev)
  98 {
  99         struct scif_dev *scifdev = &scif_dev[spdev->dnode];
 100
 101         /* In the future SCIF kernel client devices will be removed here */
 102         spdev = rcu_dereference(scifdev->spdev);
 103         if (spdev)
 104                 RCU_INIT_POINTER(scifdev->spdev, NULL);
 105         synchronize_rcu();
 106
 107         mutex_lock(&scif_info.conflock);
 108         scif_info.total--;
 109         mutex_unlock(&scif_info.conflock);
 110 }
 111
 112 static void scif_qp_setup_handler(struct work_struct *work)
 113 {
 114         struct scif_dev *scifdev = container_of(work, struct scif_dev,
 115                                                 qp_dwork.work);
 116         struct scif_hw_dev *sdev = scifdev->sdev;
 117         dma_addr_t da = 0;
 118         int err;
 119
 120         if (scif_is_mgmt_node()) {
 121                 struct mic_bootparam *bp = sdev->dp;
 122
 123                 da = bp->scif_card_dma_addr;
 124                 scifdev->rdb = bp->h2c_scif_db;
 125         } else {
 126                 struct mic_bootparam __iomem *bp = sdev->rdp;
 127
 128                 da = readq(&bp->scif_host_dma_addr);
 129                 scifdev->rdb = ioread8(&bp->c2h_scif_db);
 130         }
 131         if (da) {
 132                 err = scif_qp_response(da, scifdev);
 133                 if (err)
 134                         dev_err(&scifdev->sdev->dev,
 135                                 "scif_qp_response err %d\n", err);
 136         } else {
 137                 schedule_delayed_work(&scifdev->qp_dwork,
 138                                       msecs_to_jiffies(1000));
 139         }
 140 }
 141
 142 static int scif_setup_scifdev(struct scif_hw_dev *sdev)
 143 {
 144         int i;
 145         u8 num_nodes;
 146
 147         if (sdev->snode) {
 148                 struct mic_bootparam __iomem *bp = sdev->rdp;
 149
 150                 num_nodes = ioread8(&bp->tot_nodes);
 151         } else {
 152                 struct mic_bootparam *bp = sdev->dp;
 153
 154                 num_nodes = bp->tot_nodes;
 155         }
 156         scif_dev = kcalloc(num_nodes, sizeof(*scif_dev), GFP_KERNEL);
 157         if (!scif_dev)
 158                 return -ENOMEM;
 159         for (i = 0; i < num_nodes; i++) {
 160                 struct scif_dev *scifdev = &scif_dev[i];
 161
 162                 scifdev->node = i;
 163                 scifdev->exit = OP_IDLE;
 164                 init_waitqueue_head(&scifdev->disconn_wq);
 165                 mutex_init(&scifdev->lock);
 166                 INIT_WORK(&scifdev->init_msg_work, scif_qp_response_ack);
 167                 INIT_DELAYED_WORK(&scifdev->p2p_dwork,
 168                                   scif_poll_qp_state);
 169                 INIT_DELAYED_WORK(&scifdev->qp_dwork,
 170                                   scif_qp_setup_handler);
 171                 INIT_LIST_HEAD(&scifdev->p2p);
 172                 RCU_INIT_POINTER(scifdev->spdev, NULL);
 173         }
 174         return 0;
 175 }
 176
 177 static void scif_destroy_scifdev(void)
 178 {
 179         kfree(scif_dev);
 180 }
 181
 182 static int scif_probe(struct scif_hw_dev *sdev)
 183 {
 184         struct scif_dev *scifdev;
 185         int rc;
 186
 187         dev_set_drvdata(&sdev->dev, sdev);
 188         if (1 == atomic_add_return(1, &g_loopb_cnt)) {
 189                 struct scif_dev *loopb_dev;
 190
 191                 rc = scif_setup_scifdev(sdev);
 192                 if (rc)
 193                         goto exit;
 194                 scifdev = &scif_dev[sdev->dnode];
 195                 scifdev->sdev = sdev;
 196                 loopb_dev = &scif_dev[sdev->snode];
 197                 loopb_dev->sdev = sdev;
 198                 rc = scif_setup_loopback_qp(loopb_dev);
 199                 if (rc)
 200                         goto free_sdev;
 201         } else {
 202                 scifdev = &scif_dev[sdev->dnode];
 203                 scifdev->sdev = sdev;
 204         }
 205         rc = scif_setup_intr_wq(scifdev);
 206         if (rc)
 207                 goto destroy_loopb;
 208         rc = scif_setup_qp(scifdev);
 209         if (rc)
 210                 goto destroy_intr;
 211         scifdev->db = sdev->hw_ops->next_db(sdev);
 212         scifdev->cookie = sdev->hw_ops->request_irq(sdev, scif_intr_handler,
 213                                                     "SCIF_INTR", scifdev,
 214                                                     scifdev->db);
 215         if (IS_ERR(scifdev->cookie)) {
 216                 rc = PTR_ERR(scifdev->cookie);
 217                 goto free_qp;
 218         }
 219         if (scif_is_mgmt_node()) {
 220                 struct mic_bootparam *bp = sdev->dp;
 221
 222                 bp->c2h_scif_db = scifdev->db;
 223                 bp->scif_host_dma_addr = scifdev->qp_dma_addr;
 224         } else {
 225                 struct mic_bootparam __iomem *bp = sdev->rdp;
 226
 227                 iowrite8(scifdev->db, &bp->h2c_scif_db);
 228                 writeq(scifdev->qp_dma_addr, &bp->scif_card_dma_addr);
 229         }
 230         schedule_delayed_work(&scifdev->qp_dwork,
 231                               msecs_to_jiffies(1000));
 232         return rc;
 233 free_qp:
 234         scif_free_qp(scifdev);
 235 destroy_intr:
 236         scif_destroy_intr_wq(scifdev);
 237 destroy_loopb:
 238         if (atomic_dec_and_test(&g_loopb_cnt))
 239                 scif_destroy_loopback_qp(&scif_dev[sdev->snode]);
 240 free_sdev:
 241         scif_destroy_scifdev();
 242 exit:
 243         return rc;
 244 }
 245
 246 void scif_stop(struct scif_dev *scifdev)
 247 {
 248         struct scif_dev *dev;
 249         int i;
 250
 251         for (i = scif_info.maxid; i >= 0; i--) {
 252                 dev = &scif_dev[i];
 253                 if (scifdev_self(dev))
 254                         continue;
 255                 scif_handle_remove_node(i);
 256         }
 257 }
 258
 259 static void scif_remove(struct scif_hw_dev *sdev)
 260 {
 261         struct scif_dev *scifdev = &scif_dev[sdev->dnode];
 262
 263         if (scif_is_mgmt_node()) {
 264                 struct mic_bootparam *bp = sdev->dp;
 265
 266                 bp->c2h_scif_db = -1;
 267                 bp->scif_host_dma_addr = 0x0;
 268         } else {
 269                 struct mic_bootparam __iomem *bp = sdev->rdp;
 270
 271                 iowrite8(-1, &bp->h2c_scif_db);
 272                 writeq(0x0, &bp->scif_card_dma_addr);
 273         }
 274         if (scif_is_mgmt_node()) {
 275                 scif_disconnect_node(scifdev->node, true);
 276         } else {
 277                 scif_info.card_initiated_exit = true;
 278                 scif_stop(scifdev);
 279         }
 280         if (atomic_dec_and_test(&g_loopb_cnt))
 281                 scif_destroy_loopback_qp(&scif_dev[sdev->snode]);
 282         if (scifdev->cookie) {
 283                 sdev->hw_ops->free_irq(sdev, scifdev->cookie, scifdev);
 284                 scifdev->cookie = NULL;
 285         }
 286         scif_destroy_intr_wq(scifdev);
 287         cancel_delayed_work(&scifdev->qp_dwork);
 288         scif_free_qp(scifdev);
 289         scifdev->rdb = -1;
 290         scifdev->sdev = NULL;
 291 }
 292
 293 static struct scif_peer_driver scif_peer_driver = {
 294         .driver.name =  KBUILD_MODNAME,
 295         .driver.owner = THIS_MODULE,
 296         .probe = scif_peer_probe,
 297         .remove = scif_peer_remove,
 298 };
 299
 300 static struct scif_hw_dev_id id_table[] = {
 301         { MIC_SCIF_DEV, SCIF_DEV_ANY_ID },
 302         { 0 },
 303 };
 304
 305 static struct scif_driver scif_driver = {
 306         .driver.name =  KBUILD_MODNAME,
 307         .driver.owner = THIS_MODULE,
 308         .id_table = id_table,
 309         .probe = scif_probe,
 310         .remove = scif_remove,
 311 };
 312
 313 static int _scif_init(void)
 314 {
 315         spin_lock_init(&scif_info.eplock);
 316         spin_lock_init(&scif_info.nb_connect_lock);
 317         spin_lock_init(&scif_info.port_lock);
 318         mutex_init(&scif_info.conflock);
 319         mutex_init(&scif_info.connlock);
 320         INIT_LIST_HEAD(&scif_info.uaccept);
 321         INIT_LIST_HEAD(&scif_info.listen);
 322         INIT_LIST_HEAD(&scif_info.zombie);
 323         INIT_LIST_HEAD(&scif_info.connected);
 324         INIT_LIST_HEAD(&scif_info.disconnected);
 325         INIT_LIST_HEAD(&scif_info.nb_connect_list);
 326         init_waitqueue_head(&scif_info.exitwq);
 327         scif_info.en_msg_log = 0;
 328         scif_info.p2p_enable = 1;
 329         INIT_WORK(&scif_info.misc_work, scif_misc_handler);
 330         INIT_WORK(&scif_info.conn_work, scif_conn_handler);
 331         idr_init(&scif_ports);
 332         return 0;
 333 }
 334
 335 static void _scif_exit(void)
 336 {
 337         idr_destroy(&scif_ports);
 338         scif_destroy_scifdev();
 339 }
 340
 341 static int __init scif_init(void)
 342 {
 343         struct miscdevice *mdev = &scif_info.mdev;
 344         int rc;
 345
 346         _scif_init();
 347         rc = scif_peer_bus_init();
 348         if (rc)
 349                 goto exit;
 350         rc = scif_peer_register_driver(&scif_peer_driver);
 351         if (rc)
 352                 goto peer_bus_exit;
 353         rc = scif_register_driver(&scif_driver);
 354         if (rc)
 355                 goto unreg_scif_peer;
 356         rc = misc_register(mdev);
 357         if (rc)
 358                 goto unreg_scif;
 359         scif_init_debugfs();
 360         return 0;
 361 unreg_scif:
 362         scif_unregister_driver(&scif_driver);
 363 unreg_scif_peer:
 364         scif_peer_unregister_driver(&scif_peer_driver);
 365 peer_bus_exit:
 366         scif_peer_bus_exit();
 367 exit:
 368         _scif_exit();
 369         return rc;
 370 }
 371
 372 static void __exit scif_exit(void)
 373 {
 374         scif_exit_debugfs();
 375         misc_deregister(&scif_info.mdev);
 376         scif_unregister_driver(&scif_driver);
 377         scif_peer_unregister_driver(&scif_peer_driver);
 378         scif_peer_bus_exit();
 379         _scif_exit();
 380 }
 381
 382 module_init(scif_init);
 383 module_exit(scif_exit);
 384
 385 MODULE_DEVICE_TABLE(scif, id_table);
 386 MODULE_AUTHOR("Intel Corporation");
 387 MODULE_DESCRIPTION("Intel(R) SCIF driver");
 388 MODULE_LICENSE("GPL v2");