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
  10 #include "compat.h"
  11 #include "regs.h"
  12 #include "jr.h"
  13 #include "desc.h"
  14 #include "intern.h"
  15
  16 struct jr_driver_data {
  17         /* List of Physical JobR's with the Driver */
  18         struct list_head        jr_list;
  19         spinlock_t              jr_alloc_lock;  /* jr_list lock */
  20 } ____cacheline_aligned;
  21
  22 static struct jr_driver_data driver_data;
  23
  24 static int caam_reset_hw_jr(struct device *dev)
  25 {
  26         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
  27         unsigned int timeout = 100000;
  28
  29         /*
  30          * mask interrupts since we are going to poll
  31          * for reset completion status
  32          */
  33         setbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
  34
  35         /* initiate flush (required prior to reset) */
  36         wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
  37         while (((rd_reg32(&jrp->rregs->jrintstatus) & JRINT_ERR_HALT_MASK) ==
  38                 JRINT_ERR_HALT_INPROGRESS) && --timeout)
  39                 cpu_relax();
  40
  41         if ((rd_reg32(&jrp->rregs->jrintstatus) & JRINT_ERR_HALT_MASK) !=
  42             JRINT_ERR_HALT_COMPLETE || timeout == 0) {
  43                 dev_err(dev, "failed to flush job ring %d\n", jrp->ridx);
  44                 return -EIO;
  45         }
  46
  47         /* initiate reset */
  48         timeout = 100000;
  49         wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
  50         while ((rd_reg32(&jrp->rregs->jrcommand) & JRCR_RESET) && --timeout)
  51                 cpu_relax();
  52
  53         if (timeout == 0) {
  54                 dev_err(dev, "failed to reset job ring %d\n", jrp->ridx);
  55                 return -EIO;
  56         }
  57
  58         /* unmask interrupts */
  59         clrbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
  60
  61         return 0;
  62 }
  63
  64 /*
  65  * Shutdown JobR independent of platform property code
  66  */
  67 int caam_jr_shutdown(struct device *dev)
  68 {
  69         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
  70         dma_addr_t inpbusaddr, outbusaddr;
  71         int ret;
  72
  73         ret = caam_reset_hw_jr(dev);
  74
  75         tasklet_kill(&jrp->irqtask);
  76
  77         /* Release interrupt */
  78         free_irq(jrp->irq, dev);
  79
  80         /* Free rings */
  81         inpbusaddr = rd_reg64(&jrp->rregs->inpring_base);
  82         outbusaddr = rd_reg64(&jrp->rregs->outring_base);
  83         dma_free_coherent(dev, sizeof(dma_addr_t) * JOBR_DEPTH,
  84                           jrp->inpring, inpbusaddr);
  85         dma_free_coherent(dev, sizeof(struct jr_outentry) * JOBR_DEPTH,
  86                           jrp->outring, outbusaddr);
  87         kfree(jrp->entinfo);
  88
  89         return ret;
  90 }
  91
  92 static int caam_jr_remove(struct platform_device *pdev)
  93 {
  94         int ret;
  95         struct device *jrdev;
  96         struct caam_drv_private_jr *jrpriv;
  97
  98         jrdev = &pdev->dev;
  99         jrpriv = dev_get_drvdata(jrdev);
 100
 101         /*
 102          * Return EBUSY if job ring already allocated.
 103          */
 104         if (atomic_read(&jrpriv->tfm_count)) {
 105                 dev_err(jrdev, "Device is busy\n");
 106                 return -EBUSY;
 107         }
 108
 109         /* Remove the node from Physical JobR list maintained by driver */
 110         spin_lock(&driver_data.jr_alloc_lock);
 111         list_del(&jrpriv->list_node);
 112         spin_unlock(&driver_data.jr_alloc_lock);
 113
 114         /* Release ring */
 115         ret = caam_jr_shutdown(jrdev);
 116         if (ret)
 117                 dev_err(jrdev, "Failed to shut down job ring\n");
 118         irq_dispose_mapping(jrpriv->irq);
 119
 120         return ret;
 121 }
 122
 123 /* Main per-ring interrupt handler */
 124 static irqreturn_t caam_jr_interrupt(int irq, void *st_dev)
 125 {
 126         struct device *dev = st_dev;
 127         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 128         u32 irqstate;
 129
 130         /*
 131          * Check the output ring for ready responses, kick
 132          * tasklet if jobs done.
 133          */
 134         irqstate = rd_reg32(&jrp->rregs->jrintstatus);
 135         if (!irqstate)
 136                 return IRQ_NONE;
 137
 138         /*
 139          * If JobR error, we got more development work to do
 140          * Flag a bug now, but we really need to shut down and
 141          * restart the queue (and fix code).
 142          */
 143         if (irqstate & JRINT_JR_ERROR) {
 144                 dev_err(dev, "job ring error: irqstate: %08x\n", irqstate);
 145                 BUG();
 146         }
 147
 148         /* mask valid interrupts */
 149         setbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
 150
 151         /* Have valid interrupt at this point, just ACK and trigger */
 152         wr_reg32(&jrp->rregs->jrintstatus, irqstate);
 153
 154         preempt_disable();
 155         tasklet_schedule(&jrp->irqtask);
 156         preempt_enable();
 157
 158         return IRQ_HANDLED;
 159 }
 160
 161 /* Deferred service handler, run as interrupt-fired tasklet */
 162 static void caam_jr_dequeue(unsigned long devarg)
 163 {
 164         int hw_idx, sw_idx, i, head, tail;
 165         struct device *dev = (struct device *)devarg;
 166         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 167         void (*usercall)(struct device *dev, u32 *desc, u32 status, void *arg);
 168         u32 *userdesc, userstatus;
 169         void *userarg;
 170
 171         while (rd_reg32(&jrp->rregs->outring_used)) {
 172
 173                 head = ACCESS_ONCE(jrp->head);
 174
 175                 spin_lock(&jrp->outlock);
 176
 177                 sw_idx = tail = jrp->tail;
 178                 hw_idx = jrp->out_ring_read_index;
 179
 180                 for (i = 0; CIRC_CNT(head, tail + i, JOBR_DEPTH) >= 1; i++) {
 181                         sw_idx = (tail + i) & (JOBR_DEPTH - 1);
 182
 183                         smp_read_barrier_depends();
 184
 185                         if (jrp->outring[hw_idx].desc ==
 186                             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, jrp->outring[hw_idx].desc,
 194                                  jrp->entinfo[sw_idx].desc_size,
 195                                  DMA_TO_DEVICE);
 196
 197                 /* mark completed, avoid matching on a recycled desc addr */
 198                 jrp->entinfo[sw_idx].desc_addr_dma = 0;
 199
 200                 /* Stash callback params for use outside of lock */
 201                 usercall = jrp->entinfo[sw_idx].callbk;
 202                 userarg = jrp->entinfo[sw_idx].cbkarg;
 203                 userdesc = jrp->entinfo[sw_idx].desc_addr_virt;
 204                 userstatus = jrp->outring[hw_idx].jrstatus;
 205
 206                 /* set done */
 207                 wr_reg32(&jrp->rregs->outring_rmvd, 1);
 208
 209                 jrp->out_ring_read_index = (jrp->out_ring_read_index + 1) &
 210                                            (JOBR_DEPTH - 1);
 211
 212                 /*
 213                  * if this job completed out-of-order, do not increment
 214                  * the tail.  Otherwise, increment tail by 1 plus the
 215                  * number of subsequent jobs already completed out-of-order
 216                  */
 217                 if (sw_idx == tail) {
 218                         do {
 219                                 tail = (tail + 1) & (JOBR_DEPTH - 1);
 220                                 smp_read_barrier_depends();
 221                         } while (CIRC_CNT(head, tail, JOBR_DEPTH) >= 1 &&
 222                                  jrp->entinfo[tail].desc_addr_dma == 0);
 223
 224                         jrp->tail = tail;
 225                 }
 226
 227                 spin_unlock(&jrp->outlock);
 228
 229                 /* Finally, execute user's callback */
 230                 usercall(dev, userdesc, userstatus, userarg);
 231         }
 232
 233         /* reenable / unmask IRQs */
 234         clrbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
 235 }
 236
 237 /**
 238  * caam_jr_alloc() - Alloc a job ring for someone to use as needed.
 239  *
 240  * returns :  pointer to the newly allocated physical
 241  *            JobR dev can be written to if successful.
 242  **/
 243 struct device *caam_jr_alloc(void)
 244 {
 245         struct caam_drv_private_jr *jrpriv, *min_jrpriv = NULL;
 246         struct device *dev = NULL;
 247         int min_tfm_cnt = INT_MAX;
 248         int tfm_cnt;
 249
 250         spin_lock(&driver_data.jr_alloc_lock);
 251
 252         if (list_empty(&driver_data.jr_list)) {
 253                 spin_unlock(&driver_data.jr_alloc_lock);
 254                 return ERR_PTR(-ENODEV);
 255         }
 256
 257         list_for_each_entry(jrpriv, &driver_data.jr_list, list_node) {
 258                 tfm_cnt = atomic_read(&jrpriv->tfm_count);
 259                 if (tfm_cnt < min_tfm_cnt) {
 260                         min_tfm_cnt = tfm_cnt;
 261                         min_jrpriv = jrpriv;
 262                 }
 263                 if (!min_tfm_cnt)
 264                         break;
 265         }
 266
 267         if (min_jrpriv) {
 268                 atomic_inc(&min_jrpriv->tfm_count);
 269                 dev = min_jrpriv->dev;
 270         }
 271         spin_unlock(&driver_data.jr_alloc_lock);
 272
 273         return dev;
 274 }
 275 EXPORT_SYMBOL(caam_jr_alloc);
 276
 277 /**
 278  * caam_jr_free() - Free the Job Ring
 279  * @rdev     - points to the dev that identifies the Job ring to
 280  *             be released.
 281  **/
 282 void caam_jr_free(struct device *rdev)
 283 {
 284         struct caam_drv_private_jr *jrpriv = dev_get_drvdata(rdev);
 285
 286         atomic_dec(&jrpriv->tfm_count);
 287 }
 288 EXPORT_SYMBOL(caam_jr_free);
 289
 290 /**
 291  * caam_jr_enqueue() - Enqueue a job descriptor head. Returns 0 if OK,
 292  * -EBUSY if the queue is full, -EIO if it cannot map the caller's
 293  * descriptor.
 294  * @dev:  device of the job ring to be used. This device should have
 295  *        been assigned prior by caam_jr_register().
 296  * @desc: points to a job descriptor that execute our request. All
 297  *        descriptors (and all referenced data) must be in a DMAable
 298  *        region, and all data references must be physical addresses
 299  *        accessible to CAAM (i.e. within a PAMU window granted
 300  *        to it).
 301  * @cbk:  pointer to a callback function to be invoked upon completion
 302  *        of this request. This has the form:
 303  *        callback(struct device *dev, u32 *desc, u32 stat, void *arg)
 304  *        where:
 305  *        @dev:    contains the job ring device that processed this
 306  *                 response.
 307  *        @desc:   descriptor that initiated the request, same as
 308  *                 "desc" being argued to caam_jr_enqueue().
 309  *        @status: untranslated status received from CAAM. See the
 310  *                 reference manual for a detailed description of
 311  *                 error meaning, or see the JRSTA definitions in the
 312  *                 register header file
 313  *        @areq:   optional pointer to an argument passed with the
 314  *                 original request
 315  * @areq: optional pointer to a user argument for use at callback
 316  *        time.
 317  **/
 318 int caam_jr_enqueue(struct device *dev, u32 *desc,
 319                     void (*cbk)(struct device *dev, u32 *desc,
 320                                 u32 status, void *areq),
 321                     void *areq)
 322 {
 323         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 324         struct caam_jrentry_info *head_entry;
 325         int head, tail, desc_size;
 326         dma_addr_t desc_dma;
 327
 328         desc_size = (*desc & HDR_JD_LENGTH_MASK) * sizeof(u32);
 329         desc_dma = dma_map_single(dev, desc, desc_size, DMA_TO_DEVICE);
 330         if (dma_mapping_error(dev, desc_dma)) {
 331                 dev_err(dev, "caam_jr_enqueue(): can't map jobdesc\n");
 332                 return -EIO;
 333         }
 334
 335         spin_lock_bh(&jrp->inplock);
 336
 337         head = jrp->head;
 338         tail = ACCESS_ONCE(jrp->tail);
 339
 340         if (!rd_reg32(&jrp->rregs->inpring_avail) ||
 341             CIRC_SPACE(head, tail, JOBR_DEPTH) <= 0) {
 342                 spin_unlock_bh(&jrp->inplock);
 343                 dma_unmap_single(dev, desc_dma, desc_size, DMA_TO_DEVICE);
 344                 return -EBUSY;
 345         }
 346
 347         head_entry = &jrp->entinfo[head];
 348         head_entry->desc_addr_virt = desc;
 349         head_entry->desc_size = desc_size;
 350         head_entry->callbk = (void *)cbk;
 351         head_entry->cbkarg = areq;
 352         head_entry->desc_addr_dma = desc_dma;
 353
 354         jrp->inpring[jrp->inp_ring_write_index] = desc_dma;
 355
 356         smp_wmb();
 357
 358         jrp->inp_ring_write_index = (jrp->inp_ring_write_index + 1) &
 359                                     (JOBR_DEPTH - 1);
 360         jrp->head = (head + 1) & (JOBR_DEPTH - 1);
 361
 362         wr_reg32(&jrp->rregs->inpring_jobadd, 1);
 363
 364         spin_unlock_bh(&jrp->inplock);
 365
 366         return 0;
 367 }
 368 EXPORT_SYMBOL(caam_jr_enqueue);
 369
 370 /*
 371  * Init JobR independent of platform property detection
 372  */
 373 static int caam_jr_init(struct device *dev)
 374 {
 375         struct caam_drv_private_jr *jrp;
 376         dma_addr_t inpbusaddr, outbusaddr;
 377         int i, error;
 378
 379         jrp = dev_get_drvdata(dev);
 380
 381         tasklet_init(&jrp->irqtask, caam_jr_dequeue, (unsigned long)dev);
 382
 383         /* Connect job ring interrupt handler. */
 384         error = request_irq(jrp->irq, caam_jr_interrupt, IRQF_SHARED,
 385                             dev_name(dev), dev);
 386         if (error) {
 387                 dev_err(dev, "can't connect JobR %d interrupt (%d)\n",
 388                         jrp->ridx, jrp->irq);
 389                 irq_dispose_mapping(jrp->irq);
 390                 jrp->irq = 0;
 391                 return -EINVAL;
 392         }
 393
 394         error = caam_reset_hw_jr(dev);
 395         if (error)
 396                 return error;
 397
 398         jrp->inpring = dma_alloc_coherent(dev, sizeof(dma_addr_t) * JOBR_DEPTH,
 399                                           &inpbusaddr, GFP_KERNEL);
 400
 401         jrp->outring = dma_alloc_coherent(dev, sizeof(struct jr_outentry) *
 402                                           JOBR_DEPTH, &outbusaddr, GFP_KERNEL);
 403
 404         jrp->entinfo = kzalloc(sizeof(struct caam_jrentry_info) * JOBR_DEPTH,
 405                                GFP_KERNEL);
 406
 407         if ((jrp->inpring == NULL) || (jrp->outring == NULL) ||
 408             (jrp->entinfo == NULL)) {
 409                 dev_err(dev, "can't allocate job rings for %d\n",
 410                         jrp->ridx);
 411                 return -ENOMEM;
 412         }
 413
 414         for (i = 0; i < JOBR_DEPTH; i++)
 415                 jrp->entinfo[i].desc_addr_dma = !0;
 416
 417         /* Setup rings */
 418         jrp->inp_ring_write_index = 0;
 419         jrp->out_ring_read_index = 0;
 420         jrp->head = 0;
 421         jrp->tail = 0;
 422
 423         wr_reg64(&jrp->rregs->inpring_base, inpbusaddr);
 424         wr_reg64(&jrp->rregs->outring_base, outbusaddr);
 425         wr_reg32(&jrp->rregs->inpring_size, JOBR_DEPTH);
 426         wr_reg32(&jrp->rregs->outring_size, JOBR_DEPTH);
 427
 428         jrp->ringsize = JOBR_DEPTH;
 429
 430         spin_lock_init(&jrp->inplock);
 431         spin_lock_init(&jrp->outlock);
 432
 433         /* Select interrupt coalescing parameters */
 434         setbits32(&jrp->rregs->rconfig_lo, JOBR_INTC |
 435                   (JOBR_INTC_COUNT_THLD << JRCFG_ICDCT_SHIFT) |
 436                   (JOBR_INTC_TIME_THLD << JRCFG_ICTT_SHIFT));
 437
 438         return 0;
 439 }
 440
 441
 442 /*
 443  * Probe routine for each detected JobR subsystem.
 444  */
 445 static int caam_jr_probe(struct platform_device *pdev)
 446 {
 447         struct device *jrdev;
 448         struct device_node *nprop;
 449         struct caam_job_ring __iomem *ctrl;
 450         struct caam_drv_private_jr *jrpriv;
 451         static int total_jobrs;
 452         int error;
 453
 454         jrdev = &pdev->dev;
 455         jrpriv = kmalloc(sizeof(struct caam_drv_private_jr),
 456                          GFP_KERNEL);
 457         if (!jrpriv)
 458                 return -ENOMEM;
 459
 460         dev_set_drvdata(jrdev, jrpriv);
 461
 462         /* save ring identity relative to detection */
 463         jrpriv->ridx = total_jobrs++;
 464
 465         nprop = pdev->dev.of_node;
 466         /* Get configuration properties from device tree */
 467         /* First, get register page */
 468         ctrl = of_iomap(nprop, 0);
 469         if (!ctrl) {
 470                 dev_err(jrdev, "of_iomap() failed\n");
 471                 return -ENOMEM;
 472         }
 473
 474         jrpriv->rregs = (struct caam_job_ring __force *)ctrl;
 475
 476         if (sizeof(dma_addr_t) == sizeof(u64))
 477                 if (of_device_is_compatible(nprop, "fsl,sec-v5.0-job-ring"))
 478                         dma_set_mask(jrdev, DMA_BIT_MASK(40));
 479                 else
 480                         dma_set_mask(jrdev, DMA_BIT_MASK(36));
 481         else
 482                 dma_set_mask(jrdev, DMA_BIT_MASK(32));
 483
 484         /* Identify the interrupt */
 485         jrpriv->irq = irq_of_parse_and_map(nprop, 0);
 486
 487         /* Now do the platform independent part */
 488         error = caam_jr_init(jrdev); /* now turn on hardware */
 489         if (error) {
 490                 kfree(jrpriv);
 491                 return error;
 492         }
 493
 494         jrpriv->dev = jrdev;
 495         spin_lock(&driver_data.jr_alloc_lock);
 496         list_add_tail(&jrpriv->list_node, &driver_data.jr_list);
 497         spin_unlock(&driver_data.jr_alloc_lock);
 498
 499         atomic_set(&jrpriv->tfm_count, 0);
 500
 501         return 0;
 502 }
 503
 504 static struct of_device_id caam_jr_match[] = {
 505         {
 506                 .compatible = "fsl,sec-v4.0-job-ring",
 507         },
 508         {
 509                 .compatible = "fsl,sec4.0-job-ring",
 510         },
 511         {},
 512 };
 513 MODULE_DEVICE_TABLE(of, caam_jr_match);
 514
 515 static struct platform_driver caam_jr_driver = {
 516         .driver = {
 517                 .name = "caam_jr",
 518                 .owner = THIS_MODULE,
 519                 .of_match_table = caam_jr_match,
 520         },
 521         .probe       = caam_jr_probe,
 522         .remove      = caam_jr_remove,
 523 };
 524
 525 static int __init jr_driver_init(void)
 526 {
 527         spin_lock_init(&driver_data.jr_alloc_lock);
 528         INIT_LIST_HEAD(&driver_data.jr_list);
 529         return platform_driver_register(&caam_jr_driver);
 530 }
 531
 532 static void __exit jr_driver_exit(void)
 533 {
 534         platform_driver_unregister(&caam_jr_driver);
 535 }
 536
 537 module_init(jr_driver_init);
 538 module_exit(jr_driver_exit);
 539
 540 MODULE_LICENSE("GPL");
 541 MODULE_DESCRIPTION("FSL CAAM JR request backend");
 542 MODULE_AUTHOR("Freescale Semiconductor - NMG/STC");