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 "ctrl.h"
  13 #include "regs.h"
  14 #include "jr.h"
  15 #include "desc.h"
  16 #include "intern.h"
  17
  18 struct jr_driver_data {
  19         /* List of Physical JobR's with the Driver */
  20         struct list_head        jr_list;
  21         spinlock_t              jr_alloc_lock;  /* jr_list lock */
  22 } ____cacheline_aligned;
  23
  24 static struct jr_driver_data driver_data;
  25
  26 static int caam_reset_hw_jr(struct device *dev)
  27 {
  28         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
  29         unsigned int timeout = 100000;
  30
  31         /*
  32          * mask interrupts since we are going to poll
  33          * for reset completion status
  34          */
  35         clrsetbits_32(&jrp->rregs->rconfig_lo, 0, JRCFG_IMSK);
  36
  37         /* initiate flush (required prior to reset) */
  38         wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
  39         while (((rd_reg32(&jrp->rregs->jrintstatus) & JRINT_ERR_HALT_MASK) ==
  40                 JRINT_ERR_HALT_INPROGRESS) && --timeout)
  41                 cpu_relax();
  42
  43         if ((rd_reg32(&jrp->rregs->jrintstatus) & JRINT_ERR_HALT_MASK) !=
  44             JRINT_ERR_HALT_COMPLETE || timeout == 0) {
  45                 dev_err(dev, "failed to flush job ring %d\n", jrp->ridx);
  46                 return -EIO;
  47         }
  48
  49         /* initiate reset */
  50         timeout = 100000;
  51         wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
  52         while ((rd_reg32(&jrp->rregs->jrcommand) & JRCR_RESET) && --timeout)
  53                 cpu_relax();
  54
  55         if (timeout == 0) {
  56                 dev_err(dev, "failed to reset job ring %d\n", jrp->ridx);
  57                 return -EIO;
  58         }
  59
  60         /* unmask interrupts */
  61         clrsetbits_32(&jrp->rregs->rconfig_lo, JRCFG_IMSK, 0);
  62
  63         return 0;
  64 }
  65
  66 /*
  67  * Shutdown JobR independent of platform property code
  68  */
  69 static int caam_jr_shutdown(struct device *dev)
  70 {
  71         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
  72         dma_addr_t inpbusaddr, outbusaddr;
  73         int ret;
  74
  75         ret = caam_reset_hw_jr(dev);
  76
  77         tasklet_kill(&jrp->irqtask);
  78
  79         /* Release interrupt */
  80         free_irq(jrp->irq, dev);
  81
  82         /* Free rings */
  83         inpbusaddr = rd_reg64(&jrp->rregs->inpring_base);
  84         outbusaddr = rd_reg64(&jrp->rregs->outring_base);
  85         dma_free_coherent(dev, sizeof(dma_addr_t) * JOBR_DEPTH,
  86                           jrp->inpring, inpbusaddr);
  87         dma_free_coherent(dev, sizeof(struct jr_outentry) * JOBR_DEPTH,
  88                           jrp->outring, outbusaddr);
  89         kfree(jrp->entinfo);
  90
  91         return ret;
  92 }
  93
  94 static int caam_jr_remove(struct platform_device *pdev)
  95 {
  96         int ret;
  97         struct device *jrdev;
  98         struct caam_drv_private_jr *jrpriv;
  99
 100         jrdev = &pdev->dev;
 101         jrpriv = dev_get_drvdata(jrdev);
 102
 103         /*
 104          * Return EBUSY if job ring already allocated.
 105          */
 106         if (atomic_read(&jrpriv->tfm_count)) {
 107                 dev_err(jrdev, "Device is busy\n");
 108                 return -EBUSY;
 109         }
 110
 111         /* Remove the node from Physical JobR list maintained by driver */
 112         spin_lock(&driver_data.jr_alloc_lock);
 113         list_del(&jrpriv->list_node);
 114         spin_unlock(&driver_data.jr_alloc_lock);
 115
 116         /* Release ring */
 117         ret = caam_jr_shutdown(jrdev);
 118         if (ret)
 119                 dev_err(jrdev, "Failed to shut down job ring\n");
 120         irq_dispose_mapping(jrpriv->irq);
 121
 122         return ret;
 123 }
 124
 125 /* Main per-ring interrupt handler */
 126 static irqreturn_t caam_jr_interrupt(int irq, void *st_dev)
 127 {
 128         struct device *dev = st_dev;
 129         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 130         u32 irqstate;
 131
 132         /*
 133          * Check the output ring for ready responses, kick
 134          * tasklet if jobs done.
 135          */
 136         irqstate = rd_reg32(&jrp->rregs->jrintstatus);
 137         if (!irqstate)
 138                 return IRQ_NONE;
 139
 140         /*
 141          * If JobR error, we got more development work to do
 142          * Flag a bug now, but we really need to shut down and
 143          * restart the queue (and fix code).
 144          */
 145         if (irqstate & JRINT_JR_ERROR) {
 146                 dev_err(dev, "job ring error: irqstate: %08x\n", irqstate);
 147                 BUG();
 148         }
 149
 150         /* mask valid interrupts */
 151         clrsetbits_32(&jrp->rregs->rconfig_lo, 0, JRCFG_IMSK);
 152
 153         /* Have valid interrupt at this point, just ACK and trigger */
 154         wr_reg32(&jrp->rregs->jrintstatus, irqstate);
 155
 156         preempt_disable();
 157         tasklet_schedule(&jrp->irqtask);
 158         preempt_enable();
 159
 160         return IRQ_HANDLED;
 161 }
 162
 163 /* Deferred service handler, run as interrupt-fired tasklet */
 164 static void caam_jr_dequeue(unsigned long devarg)
 165 {
 166         int hw_idx, sw_idx, i, head, tail;
 167         struct device *dev = (struct device *)devarg;
 168         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 169         void (*usercall)(struct device *dev, u32 *desc, u32 status, void *arg);
 170         u32 *userdesc, userstatus;
 171         void *userarg;
 172
 173         while (rd_reg32(&jrp->rregs->outring_used)) {
 174
 175                 head = ACCESS_ONCE(jrp->head);
 176
 177                 spin_lock(&jrp->outlock);
 178
 179                 sw_idx = tail = jrp->tail;
 180                 hw_idx = jrp->out_ring_read_index;
 181
 182                 for (i = 0; CIRC_CNT(head, tail + i, JOBR_DEPTH) >= 1; i++) {
 183                         sw_idx = (tail + i) & (JOBR_DEPTH - 1);
 184
 185                         if (jrp->outring[hw_idx].desc ==
 186                             caam_dma_to_cpu(jrp->entinfo[sw_idx].desc_addr_dma))
 187                                 break; /* found */
 188                 }
 189                 /* we should never fail to find a matching descriptor */
 190                 BUG_ON(CIRC_CNT(head, tail + i, JOBR_DEPTH) <= 0);
 191
 192                 /* Unmap just-run descriptor so we can post-process */
 193                 dma_unmap_single(dev,
 194                                  caam_dma_to_cpu(jrp->outring[hw_idx].desc),
 195                                  jrp->entinfo[sw_idx].desc_size,
 196                                  DMA_TO_DEVICE);
 197
 198                 /* mark completed, avoid matching on a recycled desc addr */
 199                 jrp->entinfo[sw_idx].desc_addr_dma = 0;
 200
 201                 /* Stash callback params for use outside of lock */
 202                 usercall = jrp->entinfo[sw_idx].callbk;
 203                 userarg = jrp->entinfo[sw_idx].cbkarg;
 204                 userdesc = jrp->entinfo[sw_idx].desc_addr_virt;
 205                 userstatus = caam32_to_cpu(jrp->outring[hw_idx].jrstatus);
 206
 207                 /*
 208                  * Make sure all information from the job has been obtained
 209                  * before telling CAAM that the job has been removed from the
 210                  * output ring.
 211                  */
 212                 mb();
 213
 214                 /* set done */
 215                 wr_reg32(&jrp->rregs->outring_rmvd, 1);
 216
 217                 jrp->out_ring_read_index = (jrp->out_ring_read_index + 1) &
 218                                            (JOBR_DEPTH - 1);
 219
 220                 /*
 221                  * if this job completed out-of-order, do not increment
 222                  * the tail.  Otherwise, increment tail by 1 plus the
 223                  * number of subsequent jobs already completed out-of-order
 224                  */
 225                 if (sw_idx == tail) {
 226                         do {
 227                                 tail = (tail + 1) & (JOBR_DEPTH - 1);
 228                         } while (CIRC_CNT(head, tail, JOBR_DEPTH) >= 1 &&
 229                                  jrp->entinfo[tail].desc_addr_dma == 0);
 230
 231                         jrp->tail = tail;
 232                 }
 233
 234                 spin_unlock(&jrp->outlock);
 235
 236                 /* Finally, execute user's callback */
 237                 usercall(dev, userdesc, userstatus, userarg);
 238         }
 239
 240         /* reenable / unmask IRQs */
 241         clrsetbits_32(&jrp->rregs->rconfig_lo, JRCFG_IMSK, 0);
 242 }
 243
 244 /**
 245  * caam_jr_alloc() - Alloc a job ring for someone to use as needed.
 246  *
 247  * returns :  pointer to the newly allocated physical
 248  *            JobR dev can be written to if successful.
 249  **/
 250 struct device *caam_jr_alloc(void)
 251 {
 252         struct caam_drv_private_jr *jrpriv, *min_jrpriv = NULL;
 253         struct device *dev = ERR_PTR(-ENODEV);
 254         int min_tfm_cnt = INT_MAX;
 255         int tfm_cnt;
 256
 257         spin_lock(&driver_data.jr_alloc_lock);
 258
 259         if (list_empty(&driver_data.jr_list)) {
 260                 spin_unlock(&driver_data.jr_alloc_lock);
 261                 return ERR_PTR(-ENODEV);
 262         }
 263
 264         list_for_each_entry(jrpriv, &driver_data.jr_list, list_node) {
 265                 tfm_cnt = atomic_read(&jrpriv->tfm_count);
 266                 if (tfm_cnt < min_tfm_cnt) {
 267                         min_tfm_cnt = tfm_cnt;
 268                         min_jrpriv = jrpriv;
 269                 }
 270                 if (!min_tfm_cnt)
 271                         break;
 272         }
 273
 274         if (min_jrpriv) {
 275                 atomic_inc(&min_jrpriv->tfm_count);
 276                 dev = min_jrpriv->dev;
 277         }
 278         spin_unlock(&driver_data.jr_alloc_lock);
 279
 280         return dev;
 281 }
 282 EXPORT_SYMBOL(caam_jr_alloc);
 283
 284 /**
 285  * caam_jr_free() - Free the Job Ring
 286  * @rdev     - points to the dev that identifies the Job ring to
 287  *             be released.
 288  **/
 289 void caam_jr_free(struct device *rdev)
 290 {
 291         struct caam_drv_private_jr *jrpriv = dev_get_drvdata(rdev);
 292
 293         atomic_dec(&jrpriv->tfm_count);
 294 }
 295 EXPORT_SYMBOL(caam_jr_free);
 296
 297 /**
 298  * caam_jr_enqueue() - Enqueue a job descriptor head. Returns 0 if OK,
 299  * -EBUSY if the queue is full, -EIO if it cannot map the caller's
 300  * descriptor.
 301  * @dev:  device of the job ring to be used. This device should have
 302  *        been assigned prior by caam_jr_register().
 303  * @desc: points to a job descriptor that execute our request. All
 304  *        descriptors (and all referenced data) must be in a DMAable
 305  *        region, and all data references must be physical addresses
 306  *        accessible to CAAM (i.e. within a PAMU window granted
 307  *        to it).
 308  * @cbk:  pointer to a callback function to be invoked upon completion
 309  *        of this request. This has the form:
 310  *        callback(struct device *dev, u32 *desc, u32 stat, void *arg)
 311  *        where:
 312  *        @dev:    contains the job ring device that processed this
 313  *                 response.
 314  *        @desc:   descriptor that initiated the request, same as
 315  *                 "desc" being argued to caam_jr_enqueue().
 316  *        @status: untranslated status received from CAAM. See the
 317  *                 reference manual for a detailed description of
 318  *                 error meaning, or see the JRSTA definitions in the
 319  *                 register header file
 320  *        @areq:   optional pointer to an argument passed with the
 321  *                 original request
 322  * @areq: optional pointer to a user argument for use at callback
 323  *        time.
 324  **/
 325 int caam_jr_enqueue(struct device *dev, u32 *desc,
 326                     void (*cbk)(struct device *dev, u32 *desc,
 327                                 u32 status, void *areq),
 328                     void *areq)
 329 {
 330         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 331         struct caam_jrentry_info *head_entry;
 332         int head, tail, desc_size;
 333         dma_addr_t desc_dma;
 334
 335         desc_size = (caam32_to_cpu(*desc) & HDR_JD_LENGTH_MASK) * sizeof(u32);
 336         desc_dma = dma_map_single(dev, desc, desc_size, DMA_TO_DEVICE);
 337         if (dma_mapping_error(dev, desc_dma)) {
 338                 dev_err(dev, "caam_jr_enqueue(): can't map jobdesc\n");
 339                 return -EIO;
 340         }
 341
 342         spin_lock_bh(&jrp->inplock);
 343
 344         head = jrp->head;
 345         tail = ACCESS_ONCE(jrp->tail);
 346
 347         if (!rd_reg32(&jrp->rregs->inpring_avail) ||
 348             CIRC_SPACE(head, tail, JOBR_DEPTH) <= 0) {
 349                 spin_unlock_bh(&jrp->inplock);
 350                 dma_unmap_single(dev, desc_dma, desc_size, DMA_TO_DEVICE);
 351                 return -EBUSY;
 352         }
 353
 354         head_entry = &jrp->entinfo[head];
 355         head_entry->desc_addr_virt = desc;
 356         head_entry->desc_size = desc_size;
 357         head_entry->callbk = (void *)cbk;
 358         head_entry->cbkarg = areq;
 359         head_entry->desc_addr_dma = desc_dma;
 360
 361         jrp->inpring[jrp->inp_ring_write_index] = cpu_to_caam_dma(desc_dma);
 362
 363         /*
 364          * Guarantee that the descriptor's DMA address has been written to
 365          * the next slot in the ring before the write index is updated, since
 366          * other cores may update this index independently.
 367          */
 368         smp_wmb();
 369
 370         jrp->inp_ring_write_index = (jrp->inp_ring_write_index + 1) &
 371                                     (JOBR_DEPTH - 1);
 372         jrp->head = (head + 1) & (JOBR_DEPTH - 1);
 373
 374         /*
 375          * Ensure that all job information has been written before
 376          * notifying CAAM that a new job was added to the input ring.
 377          */
 378         wmb();
 379
 380         wr_reg32(&jrp->rregs->inpring_jobadd, 1);
 381
 382         spin_unlock_bh(&jrp->inplock);
 383
 384         return 0;
 385 }
 386 EXPORT_SYMBOL(caam_jr_enqueue);
 387
 388 /*
 389  * Init JobR independent of platform property detection
 390  */
 391 static int caam_jr_init(struct device *dev)
 392 {
 393         struct caam_drv_private_jr *jrp;
 394         dma_addr_t inpbusaddr, outbusaddr;
 395         int i, error;
 396
 397         jrp = dev_get_drvdata(dev);
 398
 399         tasklet_init(&jrp->irqtask, caam_jr_dequeue, (unsigned long)dev);
 400
 401         /* Connect job ring interrupt handler. */
 402         error = request_irq(jrp->irq, caam_jr_interrupt, IRQF_SHARED,
 403                             dev_name(dev), dev);
 404         if (error) {
 405                 dev_err(dev, "can't connect JobR %d interrupt (%d)\n",
 406                         jrp->ridx, jrp->irq);
 407                 goto out_kill_deq;
 408         }
 409
 410         error = caam_reset_hw_jr(dev);
 411         if (error)
 412                 goto out_free_irq;
 413
 414         error = -ENOMEM;
 415         jrp->inpring = dma_alloc_coherent(dev, sizeof(*jrp->inpring) *
 416                                           JOBR_DEPTH, &inpbusaddr, GFP_KERNEL);
 417         if (!jrp->inpring)
 418                 goto out_free_irq;
 419
 420         jrp->outring = dma_alloc_coherent(dev, sizeof(*jrp->outring) *
 421                                           JOBR_DEPTH, &outbusaddr, GFP_KERNEL);
 422         if (!jrp->outring)
 423                 goto out_free_inpring;
 424
 425         jrp->entinfo = kcalloc(JOBR_DEPTH, sizeof(*jrp->entinfo), GFP_KERNEL);
 426         if (!jrp->entinfo)
 427                 goto out_free_outring;
 428
 429         for (i = 0; i < JOBR_DEPTH; i++)
 430                 jrp->entinfo[i].desc_addr_dma = !0;
 431
 432         /* Setup rings */
 433         jrp->inp_ring_write_index = 0;
 434         jrp->out_ring_read_index = 0;
 435         jrp->head = 0;
 436         jrp->tail = 0;
 437
 438         wr_reg64(&jrp->rregs->inpring_base, inpbusaddr);
 439         wr_reg64(&jrp->rregs->outring_base, outbusaddr);
 440         wr_reg32(&jrp->rregs->inpring_size, JOBR_DEPTH);
 441         wr_reg32(&jrp->rregs->outring_size, JOBR_DEPTH);
 442
 443         jrp->ringsize = JOBR_DEPTH;
 444
 445         spin_lock_init(&jrp->inplock);
 446         spin_lock_init(&jrp->outlock);
 447
 448         /* Select interrupt coalescing parameters */
 449         clrsetbits_32(&jrp->rregs->rconfig_lo, 0, JOBR_INTC |
 450                       (JOBR_INTC_COUNT_THLD << JRCFG_ICDCT_SHIFT) |
 451                       (JOBR_INTC_TIME_THLD << JRCFG_ICTT_SHIFT));
 452
 453         return 0;
 454
 455 out_free_outring:
 456         dma_free_coherent(dev, sizeof(struct jr_outentry) * JOBR_DEPTH,
 457                           jrp->outring, outbusaddr);
 458 out_free_inpring:
 459         dma_free_coherent(dev, sizeof(dma_addr_t) * JOBR_DEPTH,
 460                           jrp->inpring, inpbusaddr);
 461         dev_err(dev, "can't allocate job rings for %d\n", jrp->ridx);
 462 out_free_irq:
 463         free_irq(jrp->irq, dev);
 464 out_kill_deq:
 465         tasklet_kill(&jrp->irqtask);
 466         return error;
 467 }
 468
 469
 470 /*
 471  * Probe routine for each detected JobR subsystem.
 472  */
 473 static int caam_jr_probe(struct platform_device *pdev)
 474 {
 475         struct device *jrdev;
 476         struct device_node *nprop;
 477         struct caam_job_ring __iomem *ctrl;
 478         struct caam_drv_private_jr *jrpriv;
 479         static int total_jobrs;
 480         int error;
 481
 482         jrdev = &pdev->dev;
 483         jrpriv = devm_kmalloc(jrdev, sizeof(*jrpriv), GFP_KERNEL);
 484         if (!jrpriv)
 485                 return -ENOMEM;
 486
 487         dev_set_drvdata(jrdev, jrpriv);
 488
 489         /* save ring identity relative to detection */
 490         jrpriv->ridx = total_jobrs++;
 491
 492         nprop = pdev->dev.of_node;
 493         /* Get configuration properties from device tree */
 494         /* First, get register page */
 495         ctrl = of_iomap(nprop, 0);
 496         if (!ctrl) {
 497                 dev_err(jrdev, "of_iomap() failed\n");
 498                 return -ENOMEM;
 499         }
 500
 501         jrpriv->rregs = (struct caam_job_ring __iomem __force *)ctrl;
 502
 503         if (sizeof(dma_addr_t) == sizeof(u64)) {
 504                 if (caam_dpaa2)
 505                         error = dma_set_mask_and_coherent(jrdev,
 506                                                           DMA_BIT_MASK(49));
 507                 else if (of_device_is_compatible(nprop,
 508                                                  "fsl,sec-v5.0-job-ring"))
 509                         error = dma_set_mask_and_coherent(jrdev,
 510                                                           DMA_BIT_MASK(40));
 511                 else
 512                         error = dma_set_mask_and_coherent(jrdev,
 513                                                           DMA_BIT_MASK(36));
 514         } else {
 515                 error = dma_set_mask_and_coherent(jrdev, DMA_BIT_MASK(32));
 516         }
 517         if (error) {
 518                 dev_err(jrdev, "dma_set_mask_and_coherent failed (%d)\n",
 519                         error);
 520                 iounmap(ctrl);
 521                 return error;
 522         }
 523
 524         /* Identify the interrupt */
 525         jrpriv->irq = irq_of_parse_and_map(nprop, 0);
 526
 527         /* Now do the platform independent part */
 528         error = caam_jr_init(jrdev); /* now turn on hardware */
 529         if (error) {
 530                 irq_dispose_mapping(jrpriv->irq);
 531                 iounmap(ctrl);
 532                 return error;
 533         }
 534
 535         jrpriv->dev = jrdev;
 536         spin_lock(&driver_data.jr_alloc_lock);
 537         list_add_tail(&jrpriv->list_node, &driver_data.jr_list);
 538         spin_unlock(&driver_data.jr_alloc_lock);
 539
 540         atomic_set(&jrpriv->tfm_count, 0);
 541
 542         return 0;
 543 }
 544
 545 static const struct of_device_id caam_jr_match[] = {
 546         {
 547                 .compatible = "fsl,sec-v4.0-job-ring",
 548         },
 549         {
 550                 .compatible = "fsl,sec4.0-job-ring",
 551         },
 552         {},
 553 };
 554 MODULE_DEVICE_TABLE(of, caam_jr_match);
 555
 556 static struct platform_driver caam_jr_driver = {
 557         .driver = {
 558                 .name = "caam_jr",
 559                 .of_match_table = caam_jr_match,
 560         },
 561         .probe       = caam_jr_probe,
 562         .remove      = caam_jr_remove,
 563 };
 564
 565 static int __init jr_driver_init(void)
 566 {
 567         spin_lock_init(&driver_data.jr_alloc_lock);
 568         INIT_LIST_HEAD(&driver_data.jr_list);
 569         return platform_driver_register(&caam_jr_driver);
 570 }
 571
 572 static void __exit jr_driver_exit(void)
 573 {
 574         platform_driver_unregister(&caam_jr_driver);
 575 }
 576
 577 module_init(jr_driver_init);
 578 module_exit(jr_driver_exit);
 579
 580 MODULE_LICENSE("GPL");
 581 MODULE_DESCRIPTION("FSL CAAM JR request backend");
 582 MODULE_AUTHOR("Freescale Semiconductor - NMG/STC");