drivers/crypto/caam/jr.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * CAAM/SEC 4.x transport/backend driver
   4  * JobR backend functionality
   5  *
   6  * Copyright 2008-2012 Freescale Semiconductor, Inc.
   7  * Copyright 2019 NXP
   8  */
   9
  10 #include <linux/of_irq.h>
  11 #include <linux/of_address.h>
  12
  13 #include "compat.h"
  14 #include "ctrl.h"
  15 #include "regs.h"
  16 #include "jr.h"
  17 #include "desc.h"
  18 #include "intern.h"
  19
  20 struct jr_driver_data {
  21         /* List of Physical JobR's with the Driver */
  22         struct list_head        jr_list;
  23         spinlock_t              jr_alloc_lock;  /* jr_list lock */
  24 } ____cacheline_aligned;
  25
  26 static struct jr_driver_data driver_data;
  27 static DEFINE_MUTEX(algs_lock);
  28 static unsigned int active_devs;
  29
  30 static void register_algs(struct device *dev)
  31 {
  32         mutex_lock(&algs_lock);
  33
  34         if (++active_devs != 1)
  35                 goto algs_unlock;
  36
  37         caam_algapi_init(dev);
  38         caam_algapi_hash_init(dev);
  39         caam_pkc_init(dev);
  40         caam_rng_init(dev);
  41         caam_qi_algapi_init(dev);
  42
  43 algs_unlock:
  44         mutex_unlock(&algs_lock);
  45 }
  46
  47 static void unregister_algs(void)
  48 {
  49         mutex_lock(&algs_lock);
  50
  51         if (--active_devs != 0)
  52                 goto algs_unlock;
  53
  54         caam_qi_algapi_exit();
  55
  56         caam_rng_exit();
  57         caam_pkc_exit();
  58         caam_algapi_hash_exit();
  59         caam_algapi_exit();
  60
  61 algs_unlock:
  62         mutex_unlock(&algs_lock);
  63 }
  64
  65 static int caam_reset_hw_jr(struct device *dev)
  66 {
  67         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
  68         unsigned int timeout = 100000;
  69
  70         /*
  71          * mask interrupts since we are going to poll
  72          * for reset completion status
  73          */
  74         clrsetbits_32(&jrp->rregs->rconfig_lo, 0, JRCFG_IMSK);
  75
  76         /* initiate flush (required prior to reset) */
  77         wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
  78         while (((rd_reg32(&jrp->rregs->jrintstatus) & JRINT_ERR_HALT_MASK) ==
  79                 JRINT_ERR_HALT_INPROGRESS) && --timeout)
  80                 cpu_relax();
  81
  82         if ((rd_reg32(&jrp->rregs->jrintstatus) & JRINT_ERR_HALT_MASK) !=
  83             JRINT_ERR_HALT_COMPLETE || timeout == 0) {
  84                 dev_err(dev, "failed to flush job ring %d\n", jrp->ridx);
  85                 return -EIO;
  86         }
  87
  88         /* initiate reset */
  89         timeout = 100000;
  90         wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
  91         while ((rd_reg32(&jrp->rregs->jrcommand) & JRCR_RESET) && --timeout)
  92                 cpu_relax();
  93
  94         if (timeout == 0) {
  95                 dev_err(dev, "failed to reset job ring %d\n", jrp->ridx);
  96                 return -EIO;
  97         }
  98
  99         /* unmask interrupts */
 100         clrsetbits_32(&jrp->rregs->rconfig_lo, JRCFG_IMSK, 0);
 101
 102         return 0;
 103 }
 104
 105 /*
 106  * Shutdown JobR independent of platform property code
 107  */
 108 static int caam_jr_shutdown(struct device *dev)
 109 {
 110         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 111         int ret;
 112
 113         ret = caam_reset_hw_jr(dev);
 114
 115         tasklet_kill(&jrp->irqtask);
 116
 117         return ret;
 118 }
 119
 120 static int caam_jr_remove(struct platform_device *pdev)
 121 {
 122         int ret;
 123         struct device *jrdev;
 124         struct caam_drv_private_jr *jrpriv;
 125
 126         jrdev = &pdev->dev;
 127         jrpriv = dev_get_drvdata(jrdev);
 128
 129         /*
 130          * Return EBUSY if job ring already allocated.
 131          */
 132         if (atomic_read(&jrpriv->tfm_count)) {
 133                 dev_err(jrdev, "Device is busy\n");
 134                 return -EBUSY;
 135         }
 136
 137         /* Unregister JR-based RNG & crypto algorithms */
 138         unregister_algs();
 139
 140         /* Remove the node from Physical JobR list maintained by driver */
 141         spin_lock(&driver_data.jr_alloc_lock);
 142         list_del(&jrpriv->list_node);
 143         spin_unlock(&driver_data.jr_alloc_lock);
 144
 145         /* Release ring */
 146         ret = caam_jr_shutdown(jrdev);
 147         if (ret)
 148                 dev_err(jrdev, "Failed to shut down job ring\n");
 149
 150         return ret;
 151 }
 152
 153 /* Main per-ring interrupt handler */
 154 static irqreturn_t caam_jr_interrupt(int irq, void *st_dev)
 155 {
 156         struct device *dev = st_dev;
 157         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 158         u32 irqstate;
 159
 160         /*
 161          * Check the output ring for ready responses, kick
 162          * tasklet if jobs done.
 163          */
 164         irqstate = rd_reg32(&jrp->rregs->jrintstatus);
 165         if (!irqstate)
 166                 return IRQ_NONE;
 167
 168         /*
 169          * If JobR error, we got more development work to do
 170          * Flag a bug now, but we really need to shut down and
 171          * restart the queue (and fix code).
 172          */
 173         if (irqstate & JRINT_JR_ERROR) {
 174                 dev_err(dev, "job ring error: irqstate: %08x\n", irqstate);
 175                 BUG();
 176         }
 177
 178         /* mask valid interrupts */
 179         clrsetbits_32(&jrp->rregs->rconfig_lo, 0, JRCFG_IMSK);
 180
 181         /* Have valid interrupt at this point, just ACK and trigger */
 182         wr_reg32(&jrp->rregs->jrintstatus, irqstate);
 183
 184         preempt_disable();
 185         tasklet_schedule(&jrp->irqtask);
 186         preempt_enable();
 187
 188         return IRQ_HANDLED;
 189 }
 190
 191 /* Deferred service handler, run as interrupt-fired tasklet */
 192 static void caam_jr_dequeue(unsigned long devarg)
 193 {
 194         int hw_idx, sw_idx, i, head, tail;
 195         struct device *dev = (struct device *)devarg;
 196         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 197         void (*usercall)(struct device *dev, u32 *desc, u32 status, void *arg);
 198         u32 *userdesc, userstatus;
 199         void *userarg;
 200         u32 outring_used = 0;
 201
 202         while (outring_used ||
 203                (outring_used = rd_reg32(&jrp->rregs->outring_used))) {
 204
 205                 head = READ_ONCE(jrp->head);
 206
 207                 sw_idx = tail = jrp->tail;
 208                 hw_idx = jrp->out_ring_read_index;
 209
 210                 for (i = 0; CIRC_CNT(head, tail + i, JOBR_DEPTH) >= 1; i++) {
 211                         sw_idx = (tail + i) & (JOBR_DEPTH - 1);
 212
 213                         if (jr_outentry_desc(jrp->outring, hw_idx) ==
 214                             caam_dma_to_cpu(jrp->entinfo[sw_idx].desc_addr_dma))
 215                                 break; /* found */
 216                 }
 217                 /* we should never fail to find a matching descriptor */
 218                 BUG_ON(CIRC_CNT(head, tail + i, JOBR_DEPTH) <= 0);
 219
 220                 /* Unmap just-run descriptor so we can post-process */
 221                 dma_unmap_single(dev,
 222                                  caam_dma_to_cpu(jr_outentry_desc(jrp->outring,
 223                                                                   hw_idx)),
 224                                  jrp->entinfo[sw_idx].desc_size,
 225                                  DMA_TO_DEVICE);
 226
 227                 /* mark completed, avoid matching on a recycled desc addr */
 228                 jrp->entinfo[sw_idx].desc_addr_dma = 0;
 229
 230                 /* Stash callback params */
 231                 usercall = jrp->entinfo[sw_idx].callbk;
 232                 userarg = jrp->entinfo[sw_idx].cbkarg;
 233                 userdesc = jrp->entinfo[sw_idx].desc_addr_virt;
 234                 userstatus = caam32_to_cpu(jr_outentry_jrstatus(jrp->outring,
 235                                                                 hw_idx));
 236
 237                 /*
 238                  * Make sure all information from the job has been obtained
 239                  * before telling CAAM that the job has been removed from the
 240                  * output ring.
 241                  */
 242                 mb();
 243
 244                 /* set done */
 245                 wr_reg32(&jrp->rregs->outring_rmvd, 1);
 246
 247                 jrp->out_ring_read_index = (jrp->out_ring_read_index + 1) &
 248                                            (JOBR_DEPTH - 1);
 249
 250                 /*
 251                  * if this job completed out-of-order, do not increment
 252                  * the tail.  Otherwise, increment tail by 1 plus the
 253                  * number of subsequent jobs already completed out-of-order
 254                  */
 255                 if (sw_idx == tail) {
 256                         do {
 257                                 tail = (tail + 1) & (JOBR_DEPTH - 1);
 258                         } while (CIRC_CNT(head, tail, JOBR_DEPTH) >= 1 &&
 259                                  jrp->entinfo[tail].desc_addr_dma == 0);
 260
 261                         jrp->tail = tail;
 262                 }
 263
 264                 /* Finally, execute user's callback */
 265                 usercall(dev, userdesc, userstatus, userarg);
 266                 outring_used--;
 267         }
 268
 269         /* reenable / unmask IRQs */
 270         clrsetbits_32(&jrp->rregs->rconfig_lo, JRCFG_IMSK, 0);
 271 }
 272
 273 /**
 274  * caam_jr_alloc() - Alloc a job ring for someone to use as needed.
 275  *
 276  * returns :  pointer to the newly allocated physical
 277  *            JobR dev can be written to if successful.
 278  **/
 279 struct device *caam_jr_alloc(void)
 280 {
 281         struct caam_drv_private_jr *jrpriv, *min_jrpriv = NULL;
 282         struct device *dev = ERR_PTR(-ENODEV);
 283         int min_tfm_cnt = INT_MAX;
 284         int tfm_cnt;
 285
 286         spin_lock(&driver_data.jr_alloc_lock);
 287
 288         if (list_empty(&driver_data.jr_list)) {
 289                 spin_unlock(&driver_data.jr_alloc_lock);
 290                 return ERR_PTR(-ENODEV);
 291         }
 292
 293         list_for_each_entry(jrpriv, &driver_data.jr_list, list_node) {
 294                 tfm_cnt = atomic_read(&jrpriv->tfm_count);
 295                 if (tfm_cnt < min_tfm_cnt) {
 296                         min_tfm_cnt = tfm_cnt;
 297                         min_jrpriv = jrpriv;
 298                 }
 299                 if (!min_tfm_cnt)
 300                         break;
 301         }
 302
 303         if (min_jrpriv) {
 304                 atomic_inc(&min_jrpriv->tfm_count);
 305                 dev = min_jrpriv->dev;
 306         }
 307         spin_unlock(&driver_data.jr_alloc_lock);
 308
 309         return dev;
 310 }
 311 EXPORT_SYMBOL(caam_jr_alloc);
 312
 313 /**
 314  * caam_jr_free() - Free the Job Ring
 315  * @rdev     - points to the dev that identifies the Job ring to
 316  *             be released.
 317  **/
 318 void caam_jr_free(struct device *rdev)
 319 {
 320         struct caam_drv_private_jr *jrpriv = dev_get_drvdata(rdev);
 321
 322         atomic_dec(&jrpriv->tfm_count);
 323 }
 324 EXPORT_SYMBOL(caam_jr_free);
 325
 326 /**
 327  * caam_jr_enqueue() - Enqueue a job descriptor head. Returns 0 if OK,
 328  * -EBUSY if the queue is full, -EIO if it cannot map the caller's
 329  * descriptor.
 330  * @dev:  device of the job ring to be used. This device should have
 331  *        been assigned prior by caam_jr_register().
 332  * @desc: points to a job descriptor that execute our request. All
 333  *        descriptors (and all referenced data) must be in a DMAable
 334  *        region, and all data references must be physical addresses
 335  *        accessible to CAAM (i.e. within a PAMU window granted
 336  *        to it).
 337  * @cbk:  pointer to a callback function to be invoked upon completion
 338  *        of this request. This has the form:
 339  *        callback(struct device *dev, u32 *desc, u32 stat, void *arg)
 340  *        where:
 341  *        @dev:    contains the job ring device that processed this
 342  *                 response.
 343  *        @desc:   descriptor that initiated the request, same as
 344  *                 "desc" being argued to caam_jr_enqueue().
 345  *        @status: untranslated status received from CAAM. See the
 346  *                 reference manual for a detailed description of
 347  *                 error meaning, or see the JRSTA definitions in the
 348  *                 register header file
 349  *        @areq:   optional pointer to an argument passed with the
 350  *                 original request
 351  * @areq: optional pointer to a user argument for use at callback
 352  *        time.
 353  **/
 354 int caam_jr_enqueue(struct device *dev, u32 *desc,
 355                     void (*cbk)(struct device *dev, u32 *desc,
 356                                 u32 status, void *areq),
 357                     void *areq)
 358 {
 359         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 360         struct caam_jrentry_info *head_entry;
 361         int head, tail, desc_size;
 362         dma_addr_t desc_dma;
 363
 364         desc_size = (caam32_to_cpu(*desc) & HDR_JD_LENGTH_MASK) * sizeof(u32);
 365         desc_dma = dma_map_single(dev, desc, desc_size, DMA_TO_DEVICE);
 366         if (dma_mapping_error(dev, desc_dma)) {
 367                 dev_err(dev, "caam_jr_enqueue(): can't map jobdesc\n");
 368                 return -EIO;
 369         }
 370
 371         spin_lock_bh(&jrp->inplock);
 372
 373         head = jrp->head;
 374         tail = READ_ONCE(jrp->tail);
 375
 376         if (!jrp->inpring_avail ||
 377             CIRC_SPACE(head, tail, JOBR_DEPTH) <= 0) {
 378                 spin_unlock_bh(&jrp->inplock);
 379                 dma_unmap_single(dev, desc_dma, desc_size, DMA_TO_DEVICE);
 380                 return -EBUSY;
 381         }
 382
 383         head_entry = &jrp->entinfo[head];
 384         head_entry->desc_addr_virt = desc;
 385         head_entry->desc_size = desc_size;
 386         head_entry->callbk = (void *)cbk;
 387         head_entry->cbkarg = areq;
 388         head_entry->desc_addr_dma = desc_dma;
 389
 390         jr_inpentry_set(jrp->inpring, head, cpu_to_caam_dma(desc_dma));
 391
 392         /*
 393          * Guarantee that the descriptor's DMA address has been written to
 394          * the next slot in the ring before the write index is updated, since
 395          * other cores may update this index independently.
 396          */
 397         smp_wmb();
 398
 399         jrp->head = (head + 1) & (JOBR_DEPTH - 1);
 400
 401         /*
 402          * Ensure that all job information has been written before
 403          * notifying CAAM that a new job was added to the input ring
 404          * using a memory barrier. The wr_reg32() uses api iowrite32()
 405          * to do the register write. iowrite32() issues a memory barrier
 406          * before the write operation.
 407          */
 408
 409         wr_reg32(&jrp->rregs->inpring_jobadd, 1);
 410
 411         jrp->inpring_avail--;
 412         if (!jrp->inpring_avail)
 413                 jrp->inpring_avail = rd_reg32(&jrp->rregs->inpring_avail);
 414
 415         spin_unlock_bh(&jrp->inplock);
 416
 417         return 0;
 418 }
 419 EXPORT_SYMBOL(caam_jr_enqueue);
 420
 421 /*
 422  * Init JobR independent of platform property detection
 423  */
 424 static int caam_jr_init(struct device *dev)
 425 {
 426         struct caam_drv_private_jr *jrp;
 427         dma_addr_t inpbusaddr, outbusaddr;
 428         int i, error;
 429
 430         jrp = dev_get_drvdata(dev);
 431
 432         error = caam_reset_hw_jr(dev);
 433         if (error)
 434                 return error;
 435
 436         jrp->inpring = dmam_alloc_coherent(dev, SIZEOF_JR_INPENTRY *
 437                                            JOBR_DEPTH, &inpbusaddr,
 438                                            GFP_KERNEL);
 439         if (!jrp->inpring)
 440                 return -ENOMEM;
 441
 442         jrp->outring = dmam_alloc_coherent(dev, SIZEOF_JR_OUTENTRY *
 443                                            JOBR_DEPTH, &outbusaddr,
 444                                            GFP_KERNEL);
 445         if (!jrp->outring)
 446                 return -ENOMEM;
 447
 448         jrp->entinfo = devm_kcalloc(dev, JOBR_DEPTH, sizeof(*jrp->entinfo),
 449                                     GFP_KERNEL);
 450         if (!jrp->entinfo)
 451                 return -ENOMEM;
 452
 453         for (i = 0; i < JOBR_DEPTH; i++)
 454                 jrp->entinfo[i].desc_addr_dma = !0;
 455
 456         /* Setup rings */
 457         jrp->out_ring_read_index = 0;
 458         jrp->head = 0;
 459         jrp->tail = 0;
 460
 461         wr_reg64(&jrp->rregs->inpring_base, inpbusaddr);
 462         wr_reg64(&jrp->rregs->outring_base, outbusaddr);
 463         wr_reg32(&jrp->rregs->inpring_size, JOBR_DEPTH);
 464         wr_reg32(&jrp->rregs->outring_size, JOBR_DEPTH);
 465
 466         jrp->inpring_avail = JOBR_DEPTH;
 467
 468         spin_lock_init(&jrp->inplock);
 469
 470         /* Select interrupt coalescing parameters */
 471         clrsetbits_32(&jrp->rregs->rconfig_lo, 0, JOBR_INTC |
 472                       (JOBR_INTC_COUNT_THLD << JRCFG_ICDCT_SHIFT) |
 473                       (JOBR_INTC_TIME_THLD << JRCFG_ICTT_SHIFT));
 474
 475         tasklet_init(&jrp->irqtask, caam_jr_dequeue, (unsigned long)dev);
 476
 477         /* Connect job ring interrupt handler. */
 478         error = devm_request_irq(dev, jrp->irq, caam_jr_interrupt, IRQF_SHARED,
 479                                  dev_name(dev), dev);
 480         if (error) {
 481                 dev_err(dev, "can't connect JobR %d interrupt (%d)\n",
 482                         jrp->ridx, jrp->irq);
 483                 tasklet_kill(&jrp->irqtask);
 484         }
 485
 486         return error;
 487 }
 488
 489 static void caam_jr_irq_dispose_mapping(void *data)
 490 {
 491         irq_dispose_mapping((unsigned long)data);
 492 }
 493
 494 /*
 495  * Probe routine for each detected JobR subsystem.
 496  */
 497 static int caam_jr_probe(struct platform_device *pdev)
 498 {
 499         struct device *jrdev;
 500         struct device_node *nprop;
 501         struct caam_job_ring __iomem *ctrl;
 502         struct caam_drv_private_jr *jrpriv;
 503         static int total_jobrs;
 504         struct resource *r;
 505         int error;
 506
 507         jrdev = &pdev->dev;
 508         jrpriv = devm_kmalloc(jrdev, sizeof(*jrpriv), GFP_KERNEL);
 509         if (!jrpriv)
 510                 return -ENOMEM;
 511
 512         dev_set_drvdata(jrdev, jrpriv);
 513
 514         /* save ring identity relative to detection */
 515         jrpriv->ridx = total_jobrs++;
 516
 517         nprop = pdev->dev.of_node;
 518         /* Get configuration properties from device tree */
 519         /* First, get register page */
 520         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 521         if (!r) {
 522                 dev_err(jrdev, "platform_get_resource() failed\n");
 523                 return -ENOMEM;
 524         }
 525
 526         ctrl = devm_ioremap(jrdev, r->start, resource_size(r));
 527         if (!ctrl) {
 528                 dev_err(jrdev, "devm_ioremap() failed\n");
 529                 return -ENOMEM;
 530         }
 531
 532         jrpriv->rregs = (struct caam_job_ring __iomem __force *)ctrl;
 533
 534         error = dma_set_mask_and_coherent(jrdev, caam_get_dma_mask(jrdev));
 535         if (error) {
 536                 dev_err(jrdev, "dma_set_mask_and_coherent failed (%d)\n",
 537                         error);
 538                 return error;
 539         }
 540
 541         /* Identify the interrupt */
 542         jrpriv->irq = irq_of_parse_and_map(nprop, 0);
 543         if (!jrpriv->irq) {
 544                 dev_err(jrdev, "irq_of_parse_and_map failed\n");
 545                 return -EINVAL;
 546         }
 547
 548         error = devm_add_action_or_reset(jrdev, caam_jr_irq_dispose_mapping,
 549                                          (void *)(unsigned long)jrpriv->irq);
 550         if (error)
 551                 return error;
 552
 553         /* Now do the platform independent part */
 554         error = caam_jr_init(jrdev); /* now turn on hardware */
 555         if (error)
 556                 return error;
 557
 558         jrpriv->dev = jrdev;
 559         spin_lock(&driver_data.jr_alloc_lock);
 560         list_add_tail(&jrpriv->list_node, &driver_data.jr_list);
 561         spin_unlock(&driver_data.jr_alloc_lock);
 562
 563         atomic_set(&jrpriv->tfm_count, 0);
 564
 565         register_algs(jrdev->parent);
 566
 567         return 0;
 568 }
 569
 570 static const struct of_device_id caam_jr_match[] = {
 571         {
 572                 .compatible = "fsl,sec-v4.0-job-ring",
 573         },
 574         {
 575                 .compatible = "fsl,sec4.0-job-ring",
 576         },
 577         {},
 578 };
 579 MODULE_DEVICE_TABLE(of, caam_jr_match);
 580
 581 static struct platform_driver caam_jr_driver = {
 582         .driver = {
 583                 .name = "caam_jr",
 584                 .of_match_table = caam_jr_match,
 585         },
 586         .probe       = caam_jr_probe,
 587         .remove      = caam_jr_remove,
 588 };
 589
 590 static int __init jr_driver_init(void)
 591 {
 592         spin_lock_init(&driver_data.jr_alloc_lock);
 593         INIT_LIST_HEAD(&driver_data.jr_list);
 594         return platform_driver_register(&caam_jr_driver);
 595 }
 596
 597 static void __exit jr_driver_exit(void)
 598 {
 599         platform_driver_unregister(&caam_jr_driver);
 600 }
 601
 602 module_init(jr_driver_init);
 603 module_exit(jr_driver_exit);
 604
 605 MODULE_LICENSE("GPL");
 606 MODULE_DESCRIPTION("FSL CAAM JR request backend");
 607 MODULE_AUTHOR("Freescale Semiconductor - NMG/STC");