kernel/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         setbits32(&jrp->rregs->rconfig_lo, 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         clrbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
  61
  62         return 0;
  63 }
  64
  65 /*
  66  * Shutdown JobR independent of platform property code
  67  */
  68 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         tasklet_kill(&jrp->irqtask);
  77
  78         /* Release interrupt */
  79         free_irq(jrp->irq, dev);
  80
  81         /* Free rings */
  82         inpbusaddr = rd_reg64(&jrp->rregs->inpring_base);
  83         outbusaddr = rd_reg64(&jrp->rregs->outring_base);
  84         dma_free_coherent(dev, sizeof(dma_addr_t) * JOBR_DEPTH,
  85                           jrp->inpring, inpbusaddr);
  86         dma_free_coherent(dev, sizeof(struct jr_outentry) * JOBR_DEPTH,
  87                           jrp->outring, outbusaddr);
  88         kfree(jrp->entinfo);
  89
  90         return ret;
  91 }
  92
  93 static int caam_jr_remove(struct platform_device *pdev)
  94 {
  95         int ret;
  96         struct device *jrdev;
  97         struct caam_drv_private_jr *jrpriv;
  98
  99         jrdev = &pdev->dev;
 100         jrpriv = dev_get_drvdata(jrdev);
 101
 102         /*
 103          * Return EBUSY if job ring already allocated.
 104          */
 105         if (atomic_read(&jrpriv->tfm_count)) {
 106                 dev_err(jrdev, "Device is busy\n");
 107                 return -EBUSY;
 108         }
 109
 110         /* Remove the node from Physical JobR list maintained by driver */
 111         spin_lock(&driver_data.jr_alloc_lock);
 112         list_del(&jrpriv->list_node);
 113         spin_unlock(&driver_data.jr_alloc_lock);
 114
 115         /* Release ring */
 116         ret = caam_jr_shutdown(jrdev);
 117         if (ret)
 118                 dev_err(jrdev, "Failed to shut down job ring\n");
 119         irq_dispose_mapping(jrpriv->irq);
 120
 121         return ret;
 122 }
 123
 124 /* Main per-ring interrupt handler */
 125 static irqreturn_t caam_jr_interrupt(int irq, void *st_dev)
 126 {
 127         struct device *dev = st_dev;
 128         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 129         u32 irqstate;
 130
 131         /*
 132          * Check the output ring for ready responses, kick
 133          * tasklet if jobs done.
 134          */
 135         irqstate = rd_reg32(&jrp->rregs->jrintstatus);
 136         if (!irqstate)
 137                 return IRQ_NONE;
 138
 139         /*
 140          * If JobR error, we got more development work to do
 141          * Flag a bug now, but we really need to shut down and
 142          * restart the queue (and fix code).
 143          */
 144         if (irqstate & JRINT_JR_ERROR) {
 145                 dev_err(dev, "job ring error: irqstate: %08x\n", irqstate);
 146                 BUG();
 147         }
 148
 149         /* mask valid interrupts */
 150         setbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
 151
 152         /* Have valid interrupt at this point, just ACK and trigger */
 153         wr_reg32(&jrp->rregs->jrintstatus, irqstate);
 154
 155         preempt_disable();
 156         tasklet_schedule(&jrp->irqtask);
 157         preempt_enable();
 158
 159         return IRQ_HANDLED;
 160 }
 161
 162 /* Deferred service handler, run as interrupt-fired tasklet */
 163 static void caam_jr_dequeue(unsigned long devarg)
 164 {
 165         int hw_idx, sw_idx, i, head, tail;
 166         struct device *dev = (struct device *)devarg;
 167         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 168         void (*usercall)(struct device *dev, u32 *desc, u32 status, void *arg);
 169         u32 *userdesc, userstatus;
 170         void *userarg;
 171
 172         while (rd_reg32(&jrp->rregs->outring_used)) {
 173
 174                 head = ACCESS_ONCE(jrp->head);
 175
 176                 spin_lock(&jrp->outlock);
 177
 178                 sw_idx = tail = jrp->tail;
 179                 hw_idx = jrp->out_ring_read_index;
 180
 181                 for (i = 0; CIRC_CNT(head, tail + i, JOBR_DEPTH) >= 1; i++) {
 182                         sw_idx = (tail + i) & (JOBR_DEPTH - 1);
 183
 184                         if (jrp->outring[hw_idx].desc ==
 185                             jrp->entinfo[sw_idx].desc_addr_dma)
 186                                 break; /* found */
 187                 }
 188                 /* we should never fail to find a matching descriptor */
 189                 BUG_ON(CIRC_CNT(head, tail + i, JOBR_DEPTH) <= 0);
 190
 191                 /* Unmap just-run descriptor so we can post-process */
 192                 dma_unmap_single(dev, jrp->outring[hw_idx].desc,
 193                                  jrp->entinfo[sw_idx].desc_size,
 194                                  DMA_TO_DEVICE);
 195
 196                 /* mark completed, avoid matching on a recycled desc addr */
 197                 jrp->entinfo[sw_idx].desc_addr_dma = 0;
 198
 199                 /* Stash callback params for use outside of lock */
 200                 usercall = jrp->entinfo[sw_idx].callbk;
 201                 userarg = jrp->entinfo[sw_idx].cbkarg;
 202                 userdesc = jrp->entinfo[sw_idx].desc_addr_virt;
 203                 userstatus = jrp->outring[hw_idx].jrstatus;
 204
 205                 /*
 206                  * Make sure all information from the job has been obtained
 207                  * before telling CAAM that the job has been removed from the
 208                  * output ring.
 209                  */
 210                 mb();
 211
 212                 /* set done */
 213                 wr_reg32(&jrp->rregs->outring_rmvd, 1);
 214
 215                 jrp->out_ring_read_index = (jrp->out_ring_read_index + 1) &
 216                                            (JOBR_DEPTH - 1);
 217
 218                 /*
 219                  * if this job completed out-of-order, do not increment
 220                  * the tail.  Otherwise, increment tail by 1 plus the
 221                  * number of subsequent jobs already completed out-of-order
 222                  */
 223                 if (sw_idx == tail) {
 224                         do {
 225                                 tail = (tail + 1) & (JOBR_DEPTH - 1);
 226                         } while (CIRC_CNT(head, tail, JOBR_DEPTH) >= 1 &&
 227                                  jrp->entinfo[tail].desc_addr_dma == 0);
 228
 229                         jrp->tail = tail;
 230                 }
 231
 232                 spin_unlock(&jrp->outlock);
 233
 234                 /* Finally, execute user's callback */
 235                 usercall(dev, userdesc, userstatus, userarg);
 236         }
 237
 238         /* reenable / unmask IRQs */
 239         clrbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
 240 }
 241
 242 /**
 243  * caam_jr_alloc() - Alloc a job ring for someone to use as needed.
 244  *
 245  * returns :  pointer to the newly allocated physical
 246  *            JobR dev can be written to if successful.
 247  **/
 248 struct device *caam_jr_alloc(void)
 249 {
 250         struct caam_drv_private_jr *jrpriv, *min_jrpriv = NULL;
 251         struct device *dev = NULL;
 252         int min_tfm_cnt = INT_MAX;
 253         int tfm_cnt;
 254
 255         spin_lock(&driver_data.jr_alloc_lock);
 256
 257         if (list_empty(&driver_data.jr_list)) {
 258                 spin_unlock(&driver_data.jr_alloc_lock);
 259                 return ERR_PTR(-ENODEV);
 260         }
 261
 262         list_for_each_entry(jrpriv, &driver_data.jr_list, list_node) {
 263                 tfm_cnt = atomic_read(&jrpriv->tfm_count);
 264                 if (tfm_cnt < min_tfm_cnt) {
 265                         min_tfm_cnt = tfm_cnt;
 266                         min_jrpriv = jrpriv;
 267                 }
 268                 if (!min_tfm_cnt)
 269                         break;
 270         }
 271
 272         if (min_jrpriv) {
 273                 atomic_inc(&min_jrpriv->tfm_count);
 274                 dev = min_jrpriv->dev;
 275         }
 276         spin_unlock(&driver_data.jr_alloc_lock);
 277
 278         return dev;
 279 }
 280 EXPORT_SYMBOL(caam_jr_alloc);
 281
 282 /**
 283  * caam_jr_free() - Free the Job Ring
 284  * @rdev     - points to the dev that identifies the Job ring to
 285  *             be released.
 286  **/
 287 void caam_jr_free(struct device *rdev)
 288 {
 289         struct caam_drv_private_jr *jrpriv = dev_get_drvdata(rdev);
 290
 291         atomic_dec(&jrpriv->tfm_count);
 292 }
 293 EXPORT_SYMBOL(caam_jr_free);
 294
 295 /**
 296  * caam_jr_enqueue() - Enqueue a job descriptor head. Returns 0 if OK,
 297  * -EBUSY if the queue is full, -EIO if it cannot map the caller's
 298  * descriptor.
 299  * @dev:  device of the job ring to be used. This device should have
 300  *        been assigned prior by caam_jr_register().
 301  * @desc: points to a job descriptor that execute our request. All
 302  *        descriptors (and all referenced data) must be in a DMAable
 303  *        region, and all data references must be physical addresses
 304  *        accessible to CAAM (i.e. within a PAMU window granted
 305  *        to it).
 306  * @cbk:  pointer to a callback function to be invoked upon completion
 307  *        of this request. This has the form:
 308  *        callback(struct device *dev, u32 *desc, u32 stat, void *arg)
 309  *        where:
 310  *        @dev:    contains the job ring device that processed this
 311  *                 response.
 312  *        @desc:   descriptor that initiated the request, same as
 313  *                 "desc" being argued to caam_jr_enqueue().
 314  *        @status: untranslated status received from CAAM. See the
 315  *                 reference manual for a detailed description of
 316  *                 error meaning, or see the JRSTA definitions in the
 317  *                 register header file
 318  *        @areq:   optional pointer to an argument passed with the
 319  *                 original request
 320  * @areq: optional pointer to a user argument for use at callback
 321  *        time.
 322  **/
 323 int caam_jr_enqueue(struct device *dev, u32 *desc,
 324                     void (*cbk)(struct device *dev, u32 *desc,
 325                                 u32 status, void *areq),
 326                     void *areq)
 327 {
 328         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 329         struct caam_jrentry_info *head_entry;
 330         int head, tail, desc_size;
 331         dma_addr_t desc_dma;
 332
 333         desc_size = (*desc & HDR_JD_LENGTH_MASK) * sizeof(u32);
 334         desc_dma = dma_map_single(dev, desc, desc_size, DMA_TO_DEVICE);
 335         if (dma_mapping_error(dev, desc_dma)) {
 336                 dev_err(dev, "caam_jr_enqueue(): can't map jobdesc\n");
 337                 return -EIO;
 338         }
 339
 340         spin_lock_bh(&jrp->inplock);
 341
 342         head = jrp->head;
 343         tail = ACCESS_ONCE(jrp->tail);
 344
 345         if (!rd_reg32(&jrp->rregs->inpring_avail) ||
 346             CIRC_SPACE(head, tail, JOBR_DEPTH) <= 0) {
 347                 spin_unlock_bh(&jrp->inplock);
 348                 dma_unmap_single(dev, desc_dma, desc_size, DMA_TO_DEVICE);
 349                 return -EBUSY;
 350         }
 351
 352         head_entry = &jrp->entinfo[head];
 353         head_entry->desc_addr_virt = desc;
 354         head_entry->desc_size = desc_size;
 355         head_entry->callbk = (void *)cbk;
 356         head_entry->cbkarg = areq;
 357         head_entry->desc_addr_dma = desc_dma;
 358
 359         jrp->inpring[jrp->inp_ring_write_index] = desc_dma;
 360
 361         /*
 362          * Guarantee that the descriptor's DMA address has been written to
 363          * the next slot in the ring before the write index is updated, since
 364          * other cores may update this index independently.
 365          */
 366         smp_wmb();
 367
 368         jrp->inp_ring_write_index = (jrp->inp_ring_write_index + 1) &
 369                                     (JOBR_DEPTH - 1);
 370         jrp->head = (head + 1) & (JOBR_DEPTH - 1);
 371
 372         /*
 373          * Ensure that all job information has been written before
 374          * notifying CAAM that a new job was added to the input ring.
 375          */
 376         wmb();
 377
 378         wr_reg32(&jrp->rregs->inpring_jobadd, 1);
 379
 380         spin_unlock_bh(&jrp->inplock);
 381
 382         return 0;
 383 }
 384 EXPORT_SYMBOL(caam_jr_enqueue);
 385
 386 /*
 387  * Init JobR independent of platform property detection
 388  */
 389 static int caam_jr_init(struct device *dev)
 390 {
 391         struct caam_drv_private_jr *jrp;
 392         dma_addr_t inpbusaddr, outbusaddr;
 393         int i, error;
 394
 395         jrp = dev_get_drvdata(dev);
 396
 397         tasklet_init(&jrp->irqtask, caam_jr_dequeue, (unsigned long)dev);
 398
 399         /* Connect job ring interrupt handler. */
 400         error = request_irq(jrp->irq, caam_jr_interrupt, IRQF_SHARED,
 401                             dev_name(dev), dev);
 402         if (error) {
 403                 dev_err(dev, "can't connect JobR %d interrupt (%d)\n",
 404                         jrp->ridx, jrp->irq);
 405                 goto out_kill_deq;
 406         }
 407
 408         error = caam_reset_hw_jr(dev);
 409         if (error)
 410                 goto out_free_irq;
 411
 412         error = -ENOMEM;
 413         jrp->inpring = dma_alloc_coherent(dev, sizeof(*jrp->inpring) *
 414                                           JOBR_DEPTH, &inpbusaddr, GFP_KERNEL);
 415         if (!jrp->inpring)
 416                 goto out_free_irq;
 417
 418         jrp->outring = dma_alloc_coherent(dev, sizeof(*jrp->outring) *
 419                                           JOBR_DEPTH, &outbusaddr, GFP_KERNEL);
 420         if (!jrp->outring)
 421                 goto out_free_inpring;
 422
 423         jrp->entinfo = kcalloc(JOBR_DEPTH, sizeof(*jrp->entinfo), GFP_KERNEL);
 424         if (!jrp->entinfo)
 425                 goto out_free_outring;
 426
 427         for (i = 0; i < JOBR_DEPTH; i++)
 428                 jrp->entinfo[i].desc_addr_dma = !0;
 429
 430         /* Setup rings */
 431         jrp->inp_ring_write_index = 0;
 432         jrp->out_ring_read_index = 0;
 433         jrp->head = 0;
 434         jrp->tail = 0;
 435
 436         wr_reg64(&jrp->rregs->inpring_base, inpbusaddr);
 437         wr_reg64(&jrp->rregs->outring_base, outbusaddr);
 438         wr_reg32(&jrp->rregs->inpring_size, JOBR_DEPTH);
 439         wr_reg32(&jrp->rregs->outring_size, JOBR_DEPTH);
 440
 441         jrp->ringsize = JOBR_DEPTH;
 442
 443         spin_lock_init(&jrp->inplock);
 444         spin_lock_init(&jrp->outlock);
 445
 446         /* Select interrupt coalescing parameters */
 447         setbits32(&jrp->rregs->rconfig_lo, JOBR_INTC |
 448                   (JOBR_INTC_COUNT_THLD << JRCFG_ICDCT_SHIFT) |
 449                   (JOBR_INTC_TIME_THLD << JRCFG_ICTT_SHIFT));
 450
 451         return 0;
 452
 453 out_free_outring:
 454         dma_free_coherent(dev, sizeof(struct jr_outentry) * JOBR_DEPTH,
 455                           jrp->outring, outbusaddr);
 456 out_free_inpring:
 457         dma_free_coherent(dev, sizeof(dma_addr_t) * JOBR_DEPTH,
 458                           jrp->inpring, inpbusaddr);
 459         dev_err(dev, "can't allocate job rings for %d\n", jrp->ridx);
 460 out_free_irq:
 461         free_irq(jrp->irq, dev);
 462 out_kill_deq:
 463         tasklet_kill(&jrp->irqtask);
 464         return error;
 465 }
 466
 467
 468 /*
 469  * Probe routine for each detected JobR subsystem.
 470  */
 471 static int caam_jr_probe(struct platform_device *pdev)
 472 {
 473         struct device *jrdev;
 474         struct device_node *nprop;
 475         struct caam_job_ring __iomem *ctrl;
 476         struct caam_drv_private_jr *jrpriv;
 477         static int total_jobrs;
 478         int error;
 479
 480         jrdev = &pdev->dev;
 481         jrpriv = devm_kmalloc(jrdev, sizeof(*jrpriv), GFP_KERNEL);
 482         if (!jrpriv)
 483                 return -ENOMEM;
 484
 485         dev_set_drvdata(jrdev, jrpriv);
 486
 487         /* save ring identity relative to detection */
 488         jrpriv->ridx = total_jobrs++;
 489
 490         nprop = pdev->dev.of_node;
 491         /* Get configuration properties from device tree */
 492         /* First, get register page */
 493         ctrl = of_iomap(nprop, 0);
 494         if (!ctrl) {
 495                 dev_err(jrdev, "of_iomap() failed\n");
 496                 return -ENOMEM;
 497         }
 498
 499         jrpriv->rregs = (struct caam_job_ring __force *)ctrl;
 500
 501         if (sizeof(dma_addr_t) == sizeof(u64))
 502                 if (of_device_is_compatible(nprop, "fsl,sec-v5.0-job-ring"))
 503                         dma_set_mask_and_coherent(jrdev, DMA_BIT_MASK(40));
 504                 else
 505                         dma_set_mask_and_coherent(jrdev, DMA_BIT_MASK(36));
 506         else
 507                 dma_set_mask_and_coherent(jrdev, DMA_BIT_MASK(32));
 508
 509         /* Identify the interrupt */
 510         jrpriv->irq = irq_of_parse_and_map(nprop, 0);
 511
 512         /* Now do the platform independent part */
 513         error = caam_jr_init(jrdev); /* now turn on hardware */
 514         if (error) {
 515                 irq_dispose_mapping(jrpriv->irq);
 516                 return error;
 517         }
 518
 519         jrpriv->dev = jrdev;
 520         spin_lock(&driver_data.jr_alloc_lock);
 521         list_add_tail(&jrpriv->list_node, &driver_data.jr_list);
 522         spin_unlock(&driver_data.jr_alloc_lock);
 523
 524         atomic_set(&jrpriv->tfm_count, 0);
 525
 526         return 0;
 527 }
 528
 529 static struct of_device_id caam_jr_match[] = {
 530         {
 531                 .compatible = "fsl,sec-v4.0-job-ring",
 532         },
 533         {
 534                 .compatible = "fsl,sec4.0-job-ring",
 535         },
 536         {},
 537 };
 538 MODULE_DEVICE_TABLE(of, caam_jr_match);
 539
 540 static struct platform_driver caam_jr_driver = {
 541         .driver = {
 542                 .name = "caam_jr",
 543                 .of_match_table = caam_jr_match,
 544         },
 545         .probe       = caam_jr_probe,
 546         .remove      = caam_jr_remove,
 547 };
 548
 549 static int __init jr_driver_init(void)
 550 {
 551         spin_lock_init(&driver_data.jr_alloc_lock);
 552         INIT_LIST_HEAD(&driver_data.jr_list);
 553         return platform_driver_register(&caam_jr_driver);
 554 }
 555
 556 static void __exit jr_driver_exit(void)
 557 {
 558         platform_driver_unregister(&caam_jr_driver);
 559 }
 560
 561 module_init(jr_driver_init);
 562 module_exit(jr_driver_exit);
 563
 564 MODULE_LICENSE("GPL");
 565 MODULE_DESCRIPTION("FSL CAAM JR request backend");
 566 MODULE_AUTHOR("Freescale Semiconductor - NMG/STC");