drivers/crypto/caam/jr.c

   1 /*
   2  * CAAM/SEC 4.x transport/backend driver
   3  * JobR backend functionality
   4  *
   5  * Copyright 2008-2012 Freescale Semiconductor, Inc.
   6  */
   7
   8 #include <linux/of_irq.h>
   9 #include <linux/of_address.h>
  10
  11 #include "compat.h"
  12 #include "regs.h"
  13 #include "jr.h"
  14 #include "desc.h"
  15 #include "intern.h"
  16
  17 struct jr_driver_data {
  18         /* List of Physical JobR's with the Driver */
  19         struct list_head        jr_list;
  20         spinlock_t              jr_alloc_lock;  /* jr_list lock */
  21 } ____cacheline_aligned;
  22
  23 static struct jr_driver_data driver_data;
  24
  25 static int caam_reset_hw_jr(struct device *dev)
  26 {
  27         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
  28         unsigned int timeout = 100000;
  29
  30         /*
  31          * mask interrupts since we are going to poll
  32          * for reset completion status
  33          */
  34         clrsetbits_32(&jrp->rregs->rconfig_lo, 0, JRCFG_IMSK);
  35
  36         /* initiate flush (required prior to reset) */
  37         wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
  38         while (((rd_reg32(&jrp->rregs->jrintstatus) & JRINT_ERR_HALT_MASK) ==
  39                 JRINT_ERR_HALT_INPROGRESS) && --timeout)
  40                 cpu_relax();
  41
  42         if ((rd_reg32(&jrp->rregs->jrintstatus) & JRINT_ERR_HALT_MASK) !=
  43             JRINT_ERR_HALT_COMPLETE || timeout == 0) {
  44                 dev_err(dev, "failed to flush job ring %d\n", jrp->ridx);
  45                 return -EIO;
  46         }
  47
  48         /* initiate reset */
  49         timeout = 100000;
  50         wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
  51         while ((rd_reg32(&jrp->rregs->jrcommand) & JRCR_RESET) && --timeout)
  52                 cpu_relax();
  53
  54         if (timeout == 0) {
  55                 dev_err(dev, "failed to reset job ring %d\n", jrp->ridx);
  56                 return -EIO;
  57         }
  58
  59         /* unmask interrupts */
  60         clrsetbits_32(&jrp->rregs->rconfig_lo, JRCFG_IMSK, 0);
  61
  62         return 0;
  63 }
  64
  65 /*
  66  * Shutdown JobR independent of platform property code
  67  */
  68 static int caam_jr_shutdown(struct device *dev)
  69 {
  70         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
  71         dma_addr_t inpbusaddr, outbusaddr;
  72         int ret;
  73
  74         ret = caam_reset_hw_jr(dev);
  75
  76         /* Release interrupt */
  77         free_irq(jrp->irq, dev);
  78
  79         /* Free rings */
  80         inpbusaddr = rd_reg64(&jrp->rregs->inpring_base);
  81         outbusaddr = rd_reg64(&jrp->rregs->outring_base);
  82         dma_free_coherent(dev, sizeof(dma_addr_t) * JOBR_DEPTH,
  83                           jrp->inpring, inpbusaddr);
  84         dma_free_coherent(dev, sizeof(struct jr_outentry) * JOBR_DEPTH,
  85                           jrp->outring, outbusaddr);
  86         kfree(jrp->entinfo);
  87
  88         return ret;
  89 }
  90
  91 static int caam_jr_remove(struct platform_device *pdev)
  92 {
  93         int ret;
  94         struct device *jrdev;
  95         struct caam_drv_private_jr *jrpriv;
  96
  97         jrdev = &pdev->dev;
  98         jrpriv = dev_get_drvdata(jrdev);
  99
 100         /*
 101          * Return EBUSY if job ring already allocated.
 102          */
 103         if (atomic_read(&jrpriv->tfm_count)) {
 104                 dev_err(jrdev, "Device is busy\n");
 105                 return -EBUSY;
 106         }
 107
 108         /* Remove the node from Physical JobR list maintained by driver */
 109         spin_lock(&driver_data.jr_alloc_lock);
 110         list_del(&jrpriv->list_node);
 111         spin_unlock(&driver_data.jr_alloc_lock);
 112
 113         /* Release ring */
 114         ret = caam_jr_shutdown(jrdev);
 115         if (ret)
 116                 dev_err(jrdev, "Failed to shut down job ring\n");
 117         irq_dispose_mapping(jrpriv->irq);
 118
 119         return ret;
 120 }
 121
 122 /* Main per-ring interrupt handler */
 123 static irqreturn_t caam_jr_interrupt(int irq, void *st_dev)
 124 {
 125         struct device *dev = st_dev;
 126         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 127         u32 irqstate;
 128
 129         /*
 130          * Check the output ring for ready responses, kick
 131          * the threaded irq if jobs done.
 132          */
 133         irqstate = rd_reg32(&jrp->rregs->jrintstatus);
 134         if (!irqstate)
 135                 return IRQ_NONE;
 136
 137         /*
 138          * If JobR error, we got more development work to do
 139          * Flag a bug now, but we really need to shut down and
 140          * restart the queue (and fix code).
 141          */
 142         if (irqstate & JRINT_JR_ERROR) {
 143                 dev_err(dev, "job ring error: irqstate: %08x\n", irqstate);
 144                 BUG();
 145         }
 146
 147         /* mask valid interrupts */
 148         clrsetbits_32(&jrp->rregs->rconfig_lo, 0, JRCFG_IMSK);
 149
 150         /* Have valid interrupt at this point, just ACK and trigger */
 151         wr_reg32(&jrp->rregs->jrintstatus, irqstate);
 152
 153         return IRQ_WAKE_THREAD;
 154 }
 155
 156 static irqreturn_t caam_jr_threadirq(int irq, void *st_dev)
 157 {
 158         int hw_idx, sw_idx, i, head, tail;
 159         struct device *dev = st_dev;
 160         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 161         void (*usercall)(struct device *dev, u32 *desc, u32 status, void *arg);
 162         u32 *userdesc, userstatus;
 163         void *userarg;
 164
 165         while (rd_reg32(&jrp->rregs->outring_used)) {
 166
 167                 head = ACCESS_ONCE(jrp->head);
 168
 169                 spin_lock(&jrp->outlock);
 170
 171                 sw_idx = tail = jrp->tail;
 172                 hw_idx = jrp->out_ring_read_index;
 173
 174                 for (i = 0; CIRC_CNT(head, tail + i, JOBR_DEPTH) >= 1; i++) {
 175                         sw_idx = (tail + i) & (JOBR_DEPTH - 1);
 176
 177                         if (jrp->outring[hw_idx].desc ==
 178                             caam_dma_to_cpu(jrp->entinfo[sw_idx].desc_addr_dma))
 179                                 break; /* found */
 180                 }
 181                 /* we should never fail to find a matching descriptor */
 182                 BUG_ON(CIRC_CNT(head, tail + i, JOBR_DEPTH) <= 0);
 183
 184                 /* Unmap just-run descriptor so we can post-process */
 185                 dma_unmap_single(dev, jrp->outring[hw_idx].desc,
 186                                  jrp->entinfo[sw_idx].desc_size,
 187                                  DMA_TO_DEVICE);
 188
 189                 /* mark completed, avoid matching on a recycled desc addr */
 190                 jrp->entinfo[sw_idx].desc_addr_dma = 0;
 191
 192                 /* Stash callback params for use outside of lock */
 193                 usercall = jrp->entinfo[sw_idx].callbk;
 194                 userarg = jrp->entinfo[sw_idx].cbkarg;
 195                 userdesc = jrp->entinfo[sw_idx].desc_addr_virt;
 196                 userstatus = caam32_to_cpu(jrp->outring[hw_idx].jrstatus);
 197
 198                 /*
 199                  * Make sure all information from the job has been obtained
 200                  * before telling CAAM that the job has been removed from the
 201                  * output ring.
 202                  */
 203                 mb();
 204
 205                 /* set done */
 206                 wr_reg32(&jrp->rregs->outring_rmvd, 1);
 207
 208                 jrp->out_ring_read_index = (jrp->out_ring_read_index + 1) &
 209                                            (JOBR_DEPTH - 1);
 210
 211                 /*
 212                  * if this job completed out-of-order, do not increment
 213                  * the tail.  Otherwise, increment tail by 1 plus the
 214                  * number of subsequent jobs already completed out-of-order
 215                  */
 216                 if (sw_idx == tail) {
 217                         do {
 218                                 tail = (tail + 1) & (JOBR_DEPTH - 1);
 219                         } while (CIRC_CNT(head, tail, JOBR_DEPTH) >= 1 &&
 220                                  jrp->entinfo[tail].desc_addr_dma == 0);
 221
 222                         jrp->tail = tail;
 223                 }
 224
 225                 spin_unlock(&jrp->outlock);
 226
 227                 /* Finally, execute user's callback */
 228                 usercall(dev, userdesc, userstatus, userarg);
 229         }
 230
 231         /* reenable / unmask IRQs */
 232         clrsetbits_32(&jrp->rregs->rconfig_lo, JRCFG_IMSK, 0);
 233
 234         return IRQ_HANDLED;
 235 }
 236
 237 /**
 238  * caam_jr_alloc() - Alloc a job ring for someone to use as needed.
 239  *
 240  * returns :  pointer to the newly allocated physical
 241  *            JobR dev can be written to if successful.
 242  **/
 243 struct device *caam_jr_alloc(void)
 244 {
 245         struct caam_drv_private_jr *jrpriv, *min_jrpriv = NULL;
 246         struct device *dev = ERR_PTR(-ENODEV);
 247         int min_tfm_cnt = INT_MAX;
 248         int tfm_cnt;
 249
 250         spin_lock(&driver_data.jr_alloc_lock);
 251
 252         if (list_empty(&driver_data.jr_list)) {
 253                 spin_unlock(&driver_data.jr_alloc_lock);
 254                 return ERR_PTR(-ENODEV);
 255         }
 256
 257         list_for_each_entry(jrpriv, &driver_data.jr_list, list_node) {
 258                 tfm_cnt = atomic_read(&jrpriv->tfm_count);
 259                 if (tfm_cnt < min_tfm_cnt) {
 260                         min_tfm_cnt = tfm_cnt;
 261                         min_jrpriv = jrpriv;
 262                 }
 263                 if (!min_tfm_cnt)
 264                         break;
 265         }
 266
 267         if (min_jrpriv) {
 268                 atomic_inc(&min_jrpriv->tfm_count);
 269                 dev = min_jrpriv->dev;
 270         }
 271         spin_unlock(&driver_data.jr_alloc_lock);
 272
 273         return dev;
 274 }
 275 EXPORT_SYMBOL(caam_jr_alloc);
 276
 277 /**
 278  * caam_jr_free() - Free the Job Ring
 279  * @rdev     - points to the dev that identifies the Job ring to
 280  *             be released.
 281  **/
 282 void caam_jr_free(struct device *rdev)
 283 {
 284         struct caam_drv_private_jr *jrpriv = dev_get_drvdata(rdev);
 285
 286         atomic_dec(&jrpriv->tfm_count);
 287 }
 288 EXPORT_SYMBOL(caam_jr_free);
 289
 290 /**
 291  * caam_jr_enqueue() - Enqueue a job descriptor head. Returns 0 if OK,
 292  * -EBUSY if the queue is full, -EIO if it cannot map the caller's
 293  * descriptor.
 294  * @dev:  device of the job ring to be used. This device should have
 295  *        been assigned prior by caam_jr_register().
 296  * @desc: points to a job descriptor that execute our request. All
 297  *        descriptors (and all referenced data) must be in a DMAable
 298  *        region, and all data references must be physical addresses
 299  *        accessible to CAAM (i.e. within a PAMU window granted
 300  *        to it).
 301  * @cbk:  pointer to a callback function to be invoked upon completion
 302  *        of this request. This has the form:
 303  *        callback(struct device *dev, u32 *desc, u32 stat, void *arg)
 304  *        where:
 305  *        @dev:    contains the job ring device that processed this
 306  *                 response.
 307  *        @desc:   descriptor that initiated the request, same as
 308  *                 "desc" being argued to caam_jr_enqueue().
 309  *        @status: untranslated status received from CAAM. See the
 310  *                 reference manual for a detailed description of
 311  *                 error meaning, or see the JRSTA definitions in the
 312  *                 register header file
 313  *        @areq:   optional pointer to an argument passed with the
 314  *                 original request
 315  * @areq: optional pointer to a user argument for use at callback
 316  *        time.
 317  **/
 318 int caam_jr_enqueue(struct device *dev, u32 *desc,
 319                     void (*cbk)(struct device *dev, u32 *desc,
 320                                 u32 status, void *areq),
 321                     void *areq)
 322 {
 323         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 324         struct caam_jrentry_info *head_entry;
 325         int head, tail, desc_size;
 326         dma_addr_t desc_dma;
 327
 328         desc_size = (caam32_to_cpu(*desc) & HDR_JD_LENGTH_MASK) * sizeof(u32);
 329         desc_dma = dma_map_single(dev, desc, desc_size, DMA_TO_DEVICE);
 330         if (dma_mapping_error(dev, desc_dma)) {
 331                 dev_err(dev, "caam_jr_enqueue(): can't map jobdesc\n");
 332                 return -EIO;
 333         }
 334
 335         spin_lock_bh(&jrp->inplock);
 336
 337         head = jrp->head;
 338         tail = ACCESS_ONCE(jrp->tail);
 339
 340         if (!rd_reg32(&jrp->rregs->inpring_avail) ||
 341             CIRC_SPACE(head, tail, JOBR_DEPTH) <= 0) {
 342                 spin_unlock_bh(&jrp->inplock);
 343                 dma_unmap_single(dev, desc_dma, desc_size, DMA_TO_DEVICE);
 344                 return -EBUSY;
 345         }
 346
 347         head_entry = &jrp->entinfo[head];
 348         head_entry->desc_addr_virt = desc;
 349         head_entry->desc_size = desc_size;
 350         head_entry->callbk = (void *)cbk;
 351         head_entry->cbkarg = areq;
 352         head_entry->desc_addr_dma = desc_dma;
 353
 354         jrp->inpring[jrp->inp_ring_write_index] = cpu_to_caam_dma(desc_dma);
 355
 356         /*
 357          * Guarantee that the descriptor's DMA address has been written to
 358          * the next slot in the ring before the write index is updated, since
 359          * other cores may update this index independently.
 360          */
 361         smp_wmb();
 362
 363         jrp->inp_ring_write_index = (jrp->inp_ring_write_index + 1) &
 364                                     (JOBR_DEPTH - 1);
 365         jrp->head = (head + 1) & (JOBR_DEPTH - 1);
 366
 367         /*
 368          * Ensure that all job information has been written before
 369          * notifying CAAM that a new job was added to the input ring.
 370          */
 371         wmb();
 372
 373         wr_reg32(&jrp->rregs->inpring_jobadd, 1);
 374
 375         spin_unlock_bh(&jrp->inplock);
 376
 377         return 0;
 378 }
 379 EXPORT_SYMBOL(caam_jr_enqueue);
 380
 381 /*
 382  * Init JobR independent of platform property detection
 383  */
 384 static int caam_jr_init(struct device *dev)
 385 {
 386         struct caam_drv_private_jr *jrp;
 387         dma_addr_t inpbusaddr, outbusaddr;
 388         int i, error;
 389
 390         jrp = dev_get_drvdata(dev);
 391
 392         /* Connect job ring interrupt handler. */
 393         error = request_threaded_irq(jrp->irq, caam_jr_interrupt,
 394                                      caam_jr_threadirq, IRQF_SHARED,
 395                                      dev_name(dev), dev);
 396         if (error) {
 397                 dev_err(dev, "can't connect JobR %d interrupt (%d)\n",
 398                         jrp->ridx, jrp->irq);
 399                 goto out_kill_deq;
 400         }
 401
 402         error = caam_reset_hw_jr(dev);
 403         if (error)
 404                 goto out_free_irq;
 405
 406         error = -ENOMEM;
 407         jrp->inpring = dma_alloc_coherent(dev, sizeof(*jrp->inpring) *
 408                                           JOBR_DEPTH, &inpbusaddr, GFP_KERNEL);
 409         if (!jrp->inpring)
 410                 goto out_free_irq;
 411
 412         jrp->outring = dma_alloc_coherent(dev, sizeof(*jrp->outring) *
 413                                           JOBR_DEPTH, &outbusaddr, GFP_KERNEL);
 414         if (!jrp->outring)
 415                 goto out_free_inpring;
 416
 417         jrp->entinfo = kcalloc(JOBR_DEPTH, sizeof(*jrp->entinfo), GFP_KERNEL);
 418         if (!jrp->entinfo)
 419                 goto out_free_outring;
 420
 421         for (i = 0; i < JOBR_DEPTH; i++)
 422                 jrp->entinfo[i].desc_addr_dma = !0;
 423
 424         /* Setup rings */
 425         jrp->inp_ring_write_index = 0;
 426         jrp->out_ring_read_index = 0;
 427         jrp->head = 0;
 428         jrp->tail = 0;
 429
 430         wr_reg64(&jrp->rregs->inpring_base, inpbusaddr);
 431         wr_reg64(&jrp->rregs->outring_base, outbusaddr);
 432         wr_reg32(&jrp->rregs->inpring_size, JOBR_DEPTH);
 433         wr_reg32(&jrp->rregs->outring_size, JOBR_DEPTH);
 434
 435         jrp->ringsize = JOBR_DEPTH;
 436
 437         spin_lock_init(&jrp->inplock);
 438         spin_lock_init(&jrp->outlock);
 439
 440         /* Select interrupt coalescing parameters */
 441         clrsetbits_32(&jrp->rregs->rconfig_lo, 0, JOBR_INTC |
 442                       (JOBR_INTC_COUNT_THLD << JRCFG_ICDCT_SHIFT) |
 443                       (JOBR_INTC_TIME_THLD << JRCFG_ICTT_SHIFT));
 444
 445         return 0;
 446
 447 out_free_outring:
 448         dma_free_coherent(dev, sizeof(struct jr_outentry) * JOBR_DEPTH,
 449                           jrp->outring, outbusaddr);
 450 out_free_inpring:
 451         dma_free_coherent(dev, sizeof(dma_addr_t) * JOBR_DEPTH,
 452                           jrp->inpring, inpbusaddr);
 453         dev_err(dev, "can't allocate job rings for %d\n", jrp->ridx);
 454 out_free_irq:
 455         free_irq(jrp->irq, dev);
 456 out_kill_deq:
 457         return error;
 458 }
 459
 460
 461 /*
 462  * Probe routine for each detected JobR subsystem.
 463  */
 464 static int caam_jr_probe(struct platform_device *pdev)
 465 {
 466         struct device *jrdev;
 467         struct device_node *nprop;
 468         struct caam_job_ring __iomem *ctrl;
 469         struct caam_drv_private_jr *jrpriv;
 470         static int total_jobrs;
 471         int error;
 472
 473         jrdev = &pdev->dev;
 474         jrpriv = devm_kmalloc(jrdev, sizeof(*jrpriv), GFP_KERNEL);
 475         if (!jrpriv)
 476                 return -ENOMEM;
 477
 478         dev_set_drvdata(jrdev, jrpriv);
 479
 480         /* save ring identity relative to detection */
 481         jrpriv->ridx = total_jobrs++;
 482
 483         nprop = pdev->dev.of_node;
 484         /* Get configuration properties from device tree */
 485         /* First, get register page */
 486         ctrl = of_iomap(nprop, 0);
 487         if (!ctrl) {
 488                 dev_err(jrdev, "of_iomap() failed\n");
 489                 return -ENOMEM;
 490         }
 491
 492         jrpriv->rregs = (struct caam_job_ring __force *)ctrl;
 493
 494         if (sizeof(dma_addr_t) == sizeof(u64))
 495                 if (of_device_is_compatible(nprop, "fsl,sec-v5.0-job-ring"))
 496                         dma_set_mask_and_coherent(jrdev, DMA_BIT_MASK(40));
 497                 else
 498                         dma_set_mask_and_coherent(jrdev, DMA_BIT_MASK(36));
 499         else
 500                 dma_set_mask_and_coherent(jrdev, DMA_BIT_MASK(32));
 501
 502         /* Identify the interrupt */
 503         jrpriv->irq = irq_of_parse_and_map(nprop, 0);
 504
 505         /* Now do the platform independent part */
 506         error = caam_jr_init(jrdev); /* now turn on hardware */
 507         if (error) {
 508                 irq_dispose_mapping(jrpriv->irq);
 509                 iounmap(ctrl);
 510                 return error;
 511         }
 512
 513         jrpriv->dev = jrdev;
 514         spin_lock(&driver_data.jr_alloc_lock);
 515         list_add_tail(&jrpriv->list_node, &driver_data.jr_list);
 516         spin_unlock(&driver_data.jr_alloc_lock);
 517
 518         atomic_set(&jrpriv->tfm_count, 0);
 519
 520         return 0;
 521 }
 522
 523 static struct of_device_id caam_jr_match[] = {
 524         {
 525                 .compatible = "fsl,sec-v4.0-job-ring",
 526         },
 527         {
 528                 .compatible = "fsl,sec4.0-job-ring",
 529         },
 530         {},
 531 };
 532 MODULE_DEVICE_TABLE(of, caam_jr_match);
 533
 534 static struct platform_driver caam_jr_driver = {
 535         .driver = {
 536                 .name = "caam_jr",
 537                 .of_match_table = caam_jr_match,
 538         },
 539         .probe       = caam_jr_probe,
 540         .remove      = caam_jr_remove,
 541 };
 542
 543 static int __init jr_driver_init(void)
 544 {
 545         spin_lock_init(&driver_data.jr_alloc_lock);
 546         INIT_LIST_HEAD(&driver_data.jr_list);
 547         return platform_driver_register(&caam_jr_driver);
 548 }
 549
 550 static void __exit jr_driver_exit(void)
 551 {
 552         platform_driver_unregister(&caam_jr_driver);
 553 }
 554
 555 module_init(jr_driver_init);
 556 module_exit(jr_driver_exit);
 557
 558 MODULE_LICENSE("GPL");
 559 MODULE_DESCRIPTION("FSL CAAM JR request backend");
 560 MODULE_AUTHOR("Freescale Semiconductor - NMG/STC");