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