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                         smp_read_barrier_depends();
 185
 186                         if (jrp->outring[hw_idx].desc ==
 187                             jrp->entinfo[sw_idx].desc_addr_dma)
 188                                 break; /* found */
 189                 }
 190                 /* we should never fail to find a matching descriptor */
 191                 BUG_ON(CIRC_CNT(head, tail + i, JOBR_DEPTH) <= 0);
 192
 193                 /* Unmap just-run descriptor so we can post-process */
 194                 dma_unmap_single(dev, 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 = jrp->outring[hw_idx].jrstatus;
 206
 207                 /* set done */
 208                 wr_reg32(&jrp->rregs->outring_rmvd, 1);
 209
 210                 jrp->out_ring_read_index = (jrp->out_ring_read_index + 1) &
 211                                            (JOBR_DEPTH - 1);
 212
 213                 /*
 214                  * if this job completed out-of-order, do not increment
 215                  * the tail.  Otherwise, increment tail by 1 plus the
 216                  * number of subsequent jobs already completed out-of-order
 217                  */
 218                 if (sw_idx == tail) {
 219                         do {
 220                                 tail = (tail + 1) & (JOBR_DEPTH - 1);
 221                                 smp_read_barrier_depends();
 222                         } while (CIRC_CNT(head, tail, JOBR_DEPTH) >= 1 &&
 223                                  jrp->entinfo[tail].desc_addr_dma == 0);
 224
 225                         jrp->tail = tail;
 226                 }
 227
 228                 spin_unlock(&jrp->outlock);
 229
 230                 /* Finally, execute user's callback */
 231                 usercall(dev, userdesc, userstatus, userarg);
 232         }
 233
 234         /* reenable / unmask IRQs */
 235         clrbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
 236 }
 237
 238 /**
 239  * caam_jr_alloc() - Alloc a job ring for someone to use as needed.
 240  *
 241  * returns :  pointer to the newly allocated physical
 242  *            JobR dev can be written to if successful.
 243  **/
 244 struct device *caam_jr_alloc(void)
 245 {
 246         struct caam_drv_private_jr *jrpriv, *min_jrpriv = NULL;
 247         struct device *dev = NULL;
 248         int min_tfm_cnt = INT_MAX;
 249         int tfm_cnt;
 250
 251         spin_lock(&driver_data.jr_alloc_lock);
 252
 253         if (list_empty(&driver_data.jr_list)) {
 254                 spin_unlock(&driver_data.jr_alloc_lock);
 255                 return ERR_PTR(-ENODEV);
 256         }
 257
 258         list_for_each_entry(jrpriv, &driver_data.jr_list, list_node) {
 259                 tfm_cnt = atomic_read(&jrpriv->tfm_count);
 260                 if (tfm_cnt < min_tfm_cnt) {
 261                         min_tfm_cnt = tfm_cnt;
 262                         min_jrpriv = jrpriv;
 263                 }
 264                 if (!min_tfm_cnt)
 265                         break;
 266         }
 267
 268         if (min_jrpriv) {
 269                 atomic_inc(&min_jrpriv->tfm_count);
 270                 dev = min_jrpriv->dev;
 271         }
 272         spin_unlock(&driver_data.jr_alloc_lock);
 273
 274         return dev;
 275 }
 276 EXPORT_SYMBOL(caam_jr_alloc);
 277
 278 /**
 279  * caam_jr_free() - Free the Job Ring
 280  * @rdev     - points to the dev that identifies the Job ring to
 281  *             be released.
 282  **/
 283 void caam_jr_free(struct device *rdev)
 284 {
 285         struct caam_drv_private_jr *jrpriv = dev_get_drvdata(rdev);
 286
 287         atomic_dec(&jrpriv->tfm_count);
 288 }
 289 EXPORT_SYMBOL(caam_jr_free);
 290
 291 /**
 292  * caam_jr_enqueue() - Enqueue a job descriptor head. Returns 0 if OK,
 293  * -EBUSY if the queue is full, -EIO if it cannot map the caller's
 294  * descriptor.
 295  * @dev:  device of the job ring to be used. This device should have
 296  *        been assigned prior by caam_jr_register().
 297  * @desc: points to a job descriptor that execute our request. All
 298  *        descriptors (and all referenced data) must be in a DMAable
 299  *        region, and all data references must be physical addresses
 300  *        accessible to CAAM (i.e. within a PAMU window granted
 301  *        to it).
 302  * @cbk:  pointer to a callback function to be invoked upon completion
 303  *        of this request. This has the form:
 304  *        callback(struct device *dev, u32 *desc, u32 stat, void *arg)
 305  *        where:
 306  *        @dev:    contains the job ring device that processed this
 307  *                 response.
 308  *        @desc:   descriptor that initiated the request, same as
 309  *                 "desc" being argued to caam_jr_enqueue().
 310  *        @status: untranslated status received from CAAM. See the
 311  *                 reference manual for a detailed description of
 312  *                 error meaning, or see the JRSTA definitions in the
 313  *                 register header file
 314  *        @areq:   optional pointer to an argument passed with the
 315  *                 original request
 316  * @areq: optional pointer to a user argument for use at callback
 317  *        time.
 318  **/
 319 int caam_jr_enqueue(struct device *dev, u32 *desc,
 320                     void (*cbk)(struct device *dev, u32 *desc,
 321                                 u32 status, void *areq),
 322                     void *areq)
 323 {
 324         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 325         struct caam_jrentry_info *head_entry;
 326         int head, tail, desc_size;
 327         dma_addr_t desc_dma;
 328
 329         desc_size = (*desc & HDR_JD_LENGTH_MASK) * sizeof(u32);
 330         desc_dma = dma_map_single(dev, desc, desc_size, DMA_TO_DEVICE);
 331         if (dma_mapping_error(dev, desc_dma)) {
 332                 dev_err(dev, "caam_jr_enqueue(): can't map jobdesc\n");
 333                 return -EIO;
 334         }
 335
 336         spin_lock_bh(&jrp->inplock);
 337
 338         head = jrp->head;
 339         tail = ACCESS_ONCE(jrp->tail);
 340
 341         if (!rd_reg32(&jrp->rregs->inpring_avail) ||
 342             CIRC_SPACE(head, tail, JOBR_DEPTH) <= 0) {
 343                 spin_unlock_bh(&jrp->inplock);
 344                 dma_unmap_single(dev, desc_dma, desc_size, DMA_TO_DEVICE);
 345                 return -EBUSY;
 346         }
 347
 348         head_entry = &jrp->entinfo[head];
 349         head_entry->desc_addr_virt = desc;
 350         head_entry->desc_size = desc_size;
 351         head_entry->callbk = (void *)cbk;
 352         head_entry->cbkarg = areq;
 353         head_entry->desc_addr_dma = desc_dma;
 354
 355         jrp->inpring[jrp->inp_ring_write_index] = desc_dma;
 356
 357         smp_wmb();
 358
 359         jrp->inp_ring_write_index = (jrp->inp_ring_write_index + 1) &
 360                                     (JOBR_DEPTH - 1);
 361         jrp->head = (head + 1) & (JOBR_DEPTH - 1);
 362
 363         wr_reg32(&jrp->rregs->inpring_jobadd, 1);
 364
 365         spin_unlock_bh(&jrp->inplock);
 366
 367         return 0;
 368 }
 369 EXPORT_SYMBOL(caam_jr_enqueue);
 370
 371 /*
 372  * Init JobR independent of platform property detection
 373  */
 374 static int caam_jr_init(struct device *dev)
 375 {
 376         struct caam_drv_private_jr *jrp;
 377         dma_addr_t inpbusaddr, outbusaddr;
 378         int i, error;
 379
 380         jrp = dev_get_drvdata(dev);
 381
 382         tasklet_init(&jrp->irqtask, caam_jr_dequeue, (unsigned long)dev);
 383
 384         /* Connect job ring interrupt handler. */
 385         error = request_irq(jrp->irq, caam_jr_interrupt, IRQF_SHARED,
 386                             dev_name(dev), dev);
 387         if (error) {
 388                 dev_err(dev, "can't connect JobR %d interrupt (%d)\n",
 389                         jrp->ridx, jrp->irq);
 390                 irq_dispose_mapping(jrp->irq);
 391                 jrp->irq = 0;
 392                 return -EINVAL;
 393         }
 394
 395         error = caam_reset_hw_jr(dev);
 396         if (error)
 397                 return error;
 398
 399         jrp->inpring = dma_alloc_coherent(dev, sizeof(dma_addr_t) * JOBR_DEPTH,
 400                                           &inpbusaddr, GFP_KERNEL);
 401
 402         jrp->outring = dma_alloc_coherent(dev, sizeof(struct jr_outentry) *
 403                                           JOBR_DEPTH, &outbusaddr, GFP_KERNEL);
 404
 405         jrp->entinfo = kzalloc(sizeof(struct caam_jrentry_info) * JOBR_DEPTH,
 406                                GFP_KERNEL);
 407
 408         if ((jrp->inpring == NULL) || (jrp->outring == NULL) ||
 409             (jrp->entinfo == NULL)) {
 410                 dev_err(dev, "can't allocate job rings for %d\n",
 411                         jrp->ridx);
 412                 return -ENOMEM;
 413         }
 414
 415         for (i = 0; i < JOBR_DEPTH; i++)
 416                 jrp->entinfo[i].desc_addr_dma = !0;
 417
 418         /* Setup rings */
 419         jrp->inp_ring_write_index = 0;
 420         jrp->out_ring_read_index = 0;
 421         jrp->head = 0;
 422         jrp->tail = 0;
 423
 424         wr_reg64(&jrp->rregs->inpring_base, inpbusaddr);
 425         wr_reg64(&jrp->rregs->outring_base, outbusaddr);
 426         wr_reg32(&jrp->rregs->inpring_size, JOBR_DEPTH);
 427         wr_reg32(&jrp->rregs->outring_size, JOBR_DEPTH);
 428
 429         jrp->ringsize = JOBR_DEPTH;
 430
 431         spin_lock_init(&jrp->inplock);
 432         spin_lock_init(&jrp->outlock);
 433
 434         /* Select interrupt coalescing parameters */
 435         setbits32(&jrp->rregs->rconfig_lo, JOBR_INTC |
 436                   (JOBR_INTC_COUNT_THLD << JRCFG_ICDCT_SHIFT) |
 437                   (JOBR_INTC_TIME_THLD << JRCFG_ICTT_SHIFT));
 438
 439         return 0;
 440 }
 441
 442
 443 /*
 444  * Probe routine for each detected JobR subsystem.
 445  */
 446 static int caam_jr_probe(struct platform_device *pdev)
 447 {
 448         struct device *jrdev;
 449         struct device_node *nprop;
 450         struct caam_job_ring __iomem *ctrl;
 451         struct caam_drv_private_jr *jrpriv;
 452         static int total_jobrs;
 453         int error;
 454
 455         jrdev = &pdev->dev;
 456         jrpriv = kmalloc(sizeof(struct caam_drv_private_jr),
 457                          GFP_KERNEL);
 458         if (!jrpriv)
 459                 return -ENOMEM;
 460
 461         dev_set_drvdata(jrdev, jrpriv);
 462
 463         /* save ring identity relative to detection */
 464         jrpriv->ridx = total_jobrs++;
 465
 466         nprop = pdev->dev.of_node;
 467         /* Get configuration properties from device tree */
 468         /* First, get register page */
 469         ctrl = of_iomap(nprop, 0);
 470         if (!ctrl) {
 471                 dev_err(jrdev, "of_iomap() failed\n");
 472                 return -ENOMEM;
 473         }
 474
 475         jrpriv->rregs = (struct caam_job_ring __force *)ctrl;
 476
 477         if (sizeof(dma_addr_t) == sizeof(u64))
 478                 if (of_device_is_compatible(nprop, "fsl,sec-v5.0-job-ring"))
 479                         dma_set_mask(jrdev, DMA_BIT_MASK(40));
 480                 else
 481                         dma_set_mask(jrdev, DMA_BIT_MASK(36));
 482         else
 483                 dma_set_mask(jrdev, DMA_BIT_MASK(32));
 484
 485         /* Identify the interrupt */
 486         jrpriv->irq = irq_of_parse_and_map(nprop, 0);
 487
 488         /* Now do the platform independent part */
 489         error = caam_jr_init(jrdev); /* now turn on hardware */
 490         if (error) {
 491                 kfree(jrpriv);
 492                 return error;
 493         }
 494
 495         jrpriv->dev = jrdev;
 496         spin_lock(&driver_data.jr_alloc_lock);
 497         list_add_tail(&jrpriv->list_node, &driver_data.jr_list);
 498         spin_unlock(&driver_data.jr_alloc_lock);
 499
 500         atomic_set(&jrpriv->tfm_count, 0);
 501
 502         return 0;
 503 }
 504
 505 static struct of_device_id caam_jr_match[] = {
 506         {
 507                 .compatible = "fsl,sec-v4.0-job-ring",
 508         },
 509         {
 510                 .compatible = "fsl,sec4.0-job-ring",
 511         },
 512         {},
 513 };
 514 MODULE_DEVICE_TABLE(of, caam_jr_match);
 515
 516 static struct platform_driver caam_jr_driver = {
 517         .driver = {
 518                 .name = "caam_jr",
 519                 .owner = THIS_MODULE,
 520                 .of_match_table = caam_jr_match,
 521         },
 522         .probe       = caam_jr_probe,
 523         .remove      = caam_jr_remove,
 524 };
 525
 526 static int __init jr_driver_init(void)
 527 {
 528         spin_lock_init(&driver_data.jr_alloc_lock);
 529         INIT_LIST_HEAD(&driver_data.jr_list);
 530         return platform_driver_register(&caam_jr_driver);
 531 }
 532
 533 static void __exit jr_driver_exit(void)
 534 {
 535         platform_driver_unregister(&caam_jr_driver);
 536 }
 537
 538 module_init(jr_driver_init);
 539 module_exit(jr_driver_exit);
 540
 541 MODULE_LICENSE("GPL");
 542 MODULE_DESCRIPTION("FSL CAAM JR request backend");
 543 MODULE_AUTHOR("Freescale Semiconductor - NMG/STC");