drivers/crypto/caam/jr.c

   1 /*
   2  * CAAM/SEC 4.x transport/backend driver
   3  * JobR backend functionality
   4  *
   5  * Copyright 2008-2011 Freescale Semiconductor, Inc.
   6  */
   7
   8 #include "compat.h"
   9 #include "regs.h"
  10 #include "jr.h"
  11 #include "desc.h"
  12 #include "intern.h"
  13
  14 /* Main per-ring interrupt handler */
  15 static irqreturn_t caam_jr_interrupt(int irq, void *st_dev)
  16 {
  17         struct device *dev = st_dev;
  18         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
  19         u32 irqstate;
  20
  21         /*
  22          * Check the output ring for ready responses, kick
  23          * tasklet if jobs done.
  24          */
  25         irqstate = rd_reg32(&jrp->rregs->jrintstatus);
  26         if (!irqstate)
  27                 return IRQ_NONE;
  28
  29         /*
  30          * If JobR error, we got more development work to do
  31          * Flag a bug now, but we really need to shut down and
  32          * restart the queue (and fix code).
  33          */
  34         if (irqstate & JRINT_JR_ERROR) {
  35                 dev_err(dev, "job ring error: irqstate: %08x\n", irqstate);
  36                 BUG();
  37         }
  38
  39         /* mask valid interrupts */
  40         setbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
  41
  42         /* Have valid interrupt at this point, just ACK and trigger */
  43         wr_reg32(&jrp->rregs->jrintstatus, irqstate);
  44
  45         preempt_disable();
  46         tasklet_schedule(&jrp->irqtask[smp_processor_id()]);
  47         preempt_enable();
  48
  49         return IRQ_HANDLED;
  50 }
  51
  52 /* Deferred service handler, run as interrupt-fired tasklet */
  53 static void caam_jr_dequeue(unsigned long devarg)
  54 {
  55         int hw_idx, sw_idx, i, head, tail;
  56         struct device *dev = (struct device *)devarg;
  57         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
  58         void (*usercall)(struct device *dev, u32 *desc, u32 status, void *arg);
  59         u32 *userdesc, userstatus;
  60         void *userarg;
  61         unsigned long flags;
  62
  63         spin_lock_irqsave(&jrp->outlock, flags);
  64
  65         head = ACCESS_ONCE(jrp->head);
  66         sw_idx = tail = jrp->tail;
  67
  68         while (CIRC_CNT(head, tail, JOBR_DEPTH) >= 1 &&
  69                rd_reg32(&jrp->rregs->outring_used)) {
  70
  71                 hw_idx = jrp->out_ring_read_index;
  72                 for (i = 0; CIRC_CNT(head, tail + i, JOBR_DEPTH) >= 1; i++) {
  73                         sw_idx = (tail + i) & (JOBR_DEPTH - 1);
  74
  75                         smp_read_barrier_depends();
  76
  77                         if (jrp->outring[hw_idx].desc ==
  78                             jrp->entinfo[sw_idx].desc_addr_dma)
  79                                 break; /* found */
  80                 }
  81                 /* we should never fail to find a matching descriptor */
  82                 BUG_ON(CIRC_CNT(head, tail + i, JOBR_DEPTH) <= 0);
  83
  84                 /* Unmap just-run descriptor so we can post-process */
  85                 dma_unmap_single(dev, jrp->outring[hw_idx].desc,
  86                                  jrp->entinfo[sw_idx].desc_size,
  87                                  DMA_TO_DEVICE);
  88
  89                 /* mark completed, avoid matching on a recycled desc addr */
  90                 jrp->entinfo[sw_idx].desc_addr_dma = 0;
  91
  92                 /* Stash callback params for use outside of lock */
  93                 usercall = jrp->entinfo[sw_idx].callbk;
  94                 userarg = jrp->entinfo[sw_idx].cbkarg;
  95                 userdesc = jrp->entinfo[sw_idx].desc_addr_virt;
  96                 userstatus = jrp->outring[hw_idx].jrstatus;
  97
  98                 smp_mb();
  99
 100                 jrp->out_ring_read_index = (jrp->out_ring_read_index + 1) &
 101                                            (JOBR_DEPTH - 1);
 102
 103                 /*
 104                  * if this job completed out-of-order, do not increment
 105                  * the tail.  Otherwise, increment tail by 1 plus the
 106                  * number of subsequent jobs already completed out-of-order
 107                  */
 108                 if (sw_idx == tail) {
 109                         do {
 110                                 tail = (tail + 1) & (JOBR_DEPTH - 1);
 111                                 smp_read_barrier_depends();
 112                         } while (CIRC_CNT(head, tail, JOBR_DEPTH) >= 1 &&
 113                                  jrp->entinfo[tail].desc_addr_dma == 0);
 114
 115                         jrp->tail = tail;
 116                 }
 117
 118                 /* set done */
 119                 wr_reg32(&jrp->rregs->outring_rmvd, 1);
 120
 121                 spin_unlock_irqrestore(&jrp->outlock, flags);
 122
 123                 /* Finally, execute user's callback */
 124                 usercall(dev, userdesc, userstatus, userarg);
 125
 126                 spin_lock_irqsave(&jrp->outlock, flags);
 127
 128                 head = ACCESS_ONCE(jrp->head);
 129                 sw_idx = tail = jrp->tail;
 130         }
 131
 132         spin_unlock_irqrestore(&jrp->outlock, flags);
 133
 134         /* reenable / unmask IRQs */
 135         clrbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
 136 }
 137
 138 /**
 139  * caam_jr_register() - Alloc a ring for someone to use as needed. Returns
 140  * an ordinal of the rings allocated, else returns -ENODEV if no rings
 141  * are available.
 142  * @ctrldev: points to the controller level dev (parent) that
 143  *           owns rings available for use.
 144  * @dev:     points to where a pointer to the newly allocated queue's
 145  *           dev can be written to if successful.
 146  **/
 147 int caam_jr_register(struct device *ctrldev, struct device **rdev)
 148 {
 149         struct caam_drv_private *ctrlpriv = dev_get_drvdata(ctrldev);
 150         struct caam_drv_private_jr *jrpriv = NULL;
 151         unsigned long flags;
 152         int ring;
 153
 154         /* Lock, if free ring - assign, unlock */
 155         spin_lock_irqsave(&ctrlpriv->jr_alloc_lock, flags);
 156         for (ring = 0; ring < ctrlpriv->total_jobrs; ring++) {
 157                 jrpriv = dev_get_drvdata(ctrlpriv->jrdev[ring]);
 158                 if (jrpriv->assign == JOBR_UNASSIGNED) {
 159                         jrpriv->assign = JOBR_ASSIGNED;
 160                         *rdev = ctrlpriv->jrdev[ring];
 161                         spin_unlock_irqrestore(&ctrlpriv->jr_alloc_lock, flags);
 162                         return ring;
 163                 }
 164         }
 165
 166         /* If assigned, write dev where caller needs it */
 167         spin_unlock_irqrestore(&ctrlpriv->jr_alloc_lock, flags);
 168         *rdev = NULL;
 169
 170         return -ENODEV;
 171 }
 172 EXPORT_SYMBOL(caam_jr_register);
 173
 174 /**
 175  * caam_jr_deregister() - Deregister an API and release the queue.
 176  * Returns 0 if OK, -EBUSY if queue still contains pending entries
 177  * or unprocessed results at the time of the call
 178  * @dev     - points to the dev that identifies the queue to
 179  *            be released.
 180  **/
 181 int caam_jr_deregister(struct device *rdev)
 182 {
 183         struct caam_drv_private_jr *jrpriv = dev_get_drvdata(rdev);
 184         struct caam_drv_private *ctrlpriv;
 185         unsigned long flags;
 186
 187         /* Get the owning controller's private space */
 188         ctrlpriv = dev_get_drvdata(jrpriv->parentdev);
 189
 190         /*
 191          * Make sure ring empty before release
 192          */
 193         if (rd_reg32(&jrpriv->rregs->outring_used) ||
 194             (rd_reg32(&jrpriv->rregs->inpring_avail) != JOBR_DEPTH))
 195                 return -EBUSY;
 196
 197         /* Release ring */
 198         spin_lock_irqsave(&ctrlpriv->jr_alloc_lock, flags);
 199         jrpriv->assign = JOBR_UNASSIGNED;
 200         spin_unlock_irqrestore(&ctrlpriv->jr_alloc_lock, flags);
 201
 202         return 0;
 203 }
 204 EXPORT_SYMBOL(caam_jr_deregister);
 205
 206 /**
 207  * caam_jr_enqueue() - Enqueue a job descriptor head. Returns 0 if OK,
 208  * -EBUSY if the queue is full, -EIO if it cannot map the caller's
 209  * descriptor.
 210  * @dev:  device of the job ring to be used. This device should have
 211  *        been assigned prior by caam_jr_register().
 212  * @desc: points to a job descriptor that execute our request. All
 213  *        descriptors (and all referenced data) must be in a DMAable
 214  *        region, and all data references must be physical addresses
 215  *        accessible to CAAM (i.e. within a PAMU window granted
 216  *        to it).
 217  * @cbk:  pointer to a callback function to be invoked upon completion
 218  *        of this request. This has the form:
 219  *        callback(struct device *dev, u32 *desc, u32 stat, void *arg)
 220  *        where:
 221  *        @dev:    contains the job ring device that processed this
 222  *                 response.
 223  *        @desc:   descriptor that initiated the request, same as
 224  *                 "desc" being argued to caam_jr_enqueue().
 225  *        @status: untranslated status received from CAAM. See the
 226  *                 reference manual for a detailed description of
 227  *                 error meaning, or see the JRSTA definitions in the
 228  *                 register header file
 229  *        @areq:   optional pointer to an argument passed with the
 230  *                 original request
 231  * @areq: optional pointer to a user argument for use at callback
 232  *        time.
 233  **/
 234 int caam_jr_enqueue(struct device *dev, u32 *desc,
 235                     void (*cbk)(struct device *dev, u32 *desc,
 236                                 u32 status, void *areq),
 237                     void *areq)
 238 {
 239         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 240         struct caam_jrentry_info *head_entry;
 241         unsigned long flags;
 242         int head, tail, desc_size;
 243         dma_addr_t desc_dma;
 244
 245         desc_size = (*desc & HDR_JD_LENGTH_MASK) * sizeof(u32);
 246         desc_dma = dma_map_single(dev, desc, desc_size, DMA_TO_DEVICE);
 247         if (dma_mapping_error(dev, desc_dma)) {
 248                 dev_err(dev, "caam_jr_enqueue(): can't map jobdesc\n");
 249                 return -EIO;
 250         }
 251
 252         spin_lock_irqsave(&jrp->inplock, flags);
 253
 254         head = jrp->head;
 255         tail = ACCESS_ONCE(jrp->tail);
 256
 257         if (!rd_reg32(&jrp->rregs->inpring_avail) ||
 258             CIRC_SPACE(head, tail, JOBR_DEPTH) <= 0) {
 259                 spin_unlock_irqrestore(&jrp->inplock, flags);
 260                 dma_unmap_single(dev, desc_dma, desc_size, DMA_TO_DEVICE);
 261                 return -EBUSY;
 262         }
 263
 264         head_entry = &jrp->entinfo[head];
 265         head_entry->desc_addr_virt = desc;
 266         head_entry->desc_size = desc_size;
 267         head_entry->callbk = (void *)cbk;
 268         head_entry->cbkarg = areq;
 269         head_entry->desc_addr_dma = desc_dma;
 270
 271         jrp->inpring[jrp->inp_ring_write_index] = desc_dma;
 272
 273         smp_wmb();
 274
 275         jrp->inp_ring_write_index = (jrp->inp_ring_write_index + 1) &
 276                                     (JOBR_DEPTH - 1);
 277         jrp->head = (head + 1) & (JOBR_DEPTH - 1);
 278
 279         wmb();
 280
 281         wr_reg32(&jrp->rregs->inpring_jobadd, 1);
 282
 283         spin_unlock_irqrestore(&jrp->inplock, flags);
 284
 285         return 0;
 286 }
 287 EXPORT_SYMBOL(caam_jr_enqueue);
 288
 289 static int caam_reset_hw_jr(struct device *dev)
 290 {
 291         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 292         unsigned int timeout = 100000;
 293
 294         /*
 295          * mask interrupts since we are going to poll
 296          * for reset completion status
 297          */
 298         setbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
 299
 300         /* initiate flush (required prior to reset) */
 301         wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
 302         while (((rd_reg32(&jrp->rregs->jrintstatus) & JRINT_ERR_HALT_MASK) ==
 303                 JRINT_ERR_HALT_INPROGRESS) && --timeout)
 304                 cpu_relax();
 305
 306         if ((rd_reg32(&jrp->rregs->jrintstatus) & JRINT_ERR_HALT_MASK) !=
 307             JRINT_ERR_HALT_COMPLETE || timeout == 0) {
 308                 dev_err(dev, "failed to flush job ring %d\n", jrp->ridx);
 309                 return -EIO;
 310         }
 311
 312         /* initiate reset */
 313         timeout = 100000;
 314         wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
 315         while ((rd_reg32(&jrp->rregs->jrcommand) & JRCR_RESET) && --timeout)
 316                 cpu_relax();
 317
 318         if (timeout == 0) {
 319                 dev_err(dev, "failed to reset job ring %d\n", jrp->ridx);
 320                 return -EIO;
 321         }
 322
 323         /* unmask interrupts */
 324         clrbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
 325
 326         return 0;
 327 }
 328
 329 /*
 330  * Init JobR independent of platform property detection
 331  */
 332 static int caam_jr_init(struct device *dev)
 333 {
 334         struct caam_drv_private_jr *jrp;
 335         dma_addr_t inpbusaddr, outbusaddr;
 336         int i, error;
 337
 338         jrp = dev_get_drvdata(dev);
 339
 340         /* Connect job ring interrupt handler. */
 341         for_each_possible_cpu(i)
 342                 tasklet_init(&jrp->irqtask[i], caam_jr_dequeue,
 343                              (unsigned long)dev);
 344
 345         error = request_irq(jrp->irq, caam_jr_interrupt, IRQF_SHARED,
 346                             "caam-jobr", dev);
 347         if (error) {
 348                 dev_err(dev, "can't connect JobR %d interrupt (%d)\n",
 349                         jrp->ridx, jrp->irq);
 350                 irq_dispose_mapping(jrp->irq);
 351                 jrp->irq = 0;
 352                 return -EINVAL;
 353         }
 354
 355         error = caam_reset_hw_jr(dev);
 356         if (error)
 357                 return error;
 358
 359         jrp->inpring = kzalloc(sizeof(dma_addr_t) * JOBR_DEPTH,
 360                                GFP_KERNEL | GFP_DMA);
 361         jrp->outring = kzalloc(sizeof(struct jr_outentry) *
 362                                JOBR_DEPTH, GFP_KERNEL | GFP_DMA);
 363
 364         jrp->entinfo = kzalloc(sizeof(struct caam_jrentry_info) * JOBR_DEPTH,
 365                                GFP_KERNEL);
 366
 367         if ((jrp->inpring == NULL) || (jrp->outring == NULL) ||
 368             (jrp->entinfo == NULL)) {
 369                 dev_err(dev, "can't allocate job rings for %d\n",
 370                         jrp->ridx);
 371                 return -ENOMEM;
 372         }
 373
 374         for (i = 0; i < JOBR_DEPTH; i++)
 375                 jrp->entinfo[i].desc_addr_dma = !0;
 376
 377         /* Setup rings */
 378         inpbusaddr = dma_map_single(dev, jrp->inpring,
 379                                     sizeof(u32 *) * JOBR_DEPTH,
 380                                     DMA_BIDIRECTIONAL);
 381         if (dma_mapping_error(dev, inpbusaddr)) {
 382                 dev_err(dev, "caam_jr_init(): can't map input ring\n");
 383                 kfree(jrp->inpring);
 384                 kfree(jrp->outring);
 385                 kfree(jrp->entinfo);
 386                 return -EIO;
 387         }
 388
 389         outbusaddr = dma_map_single(dev, jrp->outring,
 390                                     sizeof(struct jr_outentry) * JOBR_DEPTH,
 391                                     DMA_BIDIRECTIONAL);
 392         if (dma_mapping_error(dev, outbusaddr)) {
 393                 dev_err(dev, "caam_jr_init(): can't map output ring\n");
 394                         dma_unmap_single(dev, inpbusaddr,
 395                                          sizeof(u32 *) * JOBR_DEPTH,
 396                                          DMA_BIDIRECTIONAL);
 397                 kfree(jrp->inpring);
 398                 kfree(jrp->outring);
 399                 kfree(jrp->entinfo);
 400                 return -EIO;
 401         }
 402
 403         jrp->inp_ring_write_index = 0;
 404         jrp->out_ring_read_index = 0;
 405         jrp->head = 0;
 406         jrp->tail = 0;
 407
 408         wr_reg64(&jrp->rregs->inpring_base, inpbusaddr);
 409         wr_reg64(&jrp->rregs->outring_base, outbusaddr);
 410         wr_reg32(&jrp->rregs->inpring_size, JOBR_DEPTH);
 411         wr_reg32(&jrp->rregs->outring_size, JOBR_DEPTH);
 412
 413         jrp->ringsize = JOBR_DEPTH;
 414
 415         spin_lock_init(&jrp->inplock);
 416         spin_lock_init(&jrp->outlock);
 417
 418         /* Select interrupt coalescing parameters */
 419         setbits32(&jrp->rregs->rconfig_lo, JOBR_INTC |
 420                   (JOBR_INTC_COUNT_THLD << JRCFG_ICDCT_SHIFT) |
 421                   (JOBR_INTC_TIME_THLD << JRCFG_ICTT_SHIFT));
 422
 423         jrp->assign = JOBR_UNASSIGNED;
 424         return 0;
 425 }
 426
 427 /*
 428  * Shutdown JobR independent of platform property code
 429  */
 430 int caam_jr_shutdown(struct device *dev)
 431 {
 432         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 433         dma_addr_t inpbusaddr, outbusaddr;
 434         int ret, i;
 435
 436         ret = caam_reset_hw_jr(dev);
 437
 438         for_each_possible_cpu(i)
 439                 tasklet_kill(&jrp->irqtask[i]);
 440
 441         /* Release interrupt */
 442         free_irq(jrp->irq, dev);
 443
 444         /* Free rings */
 445         inpbusaddr = rd_reg64(&jrp->rregs->inpring_base);
 446         outbusaddr = rd_reg64(&jrp->rregs->outring_base);
 447         dma_unmap_single(dev, outbusaddr,
 448                          sizeof(struct jr_outentry) * JOBR_DEPTH,
 449                          DMA_BIDIRECTIONAL);
 450         dma_unmap_single(dev, inpbusaddr, sizeof(u32 *) * JOBR_DEPTH,
 451                          DMA_BIDIRECTIONAL);
 452         kfree(jrp->outring);
 453         kfree(jrp->inpring);
 454         kfree(jrp->entinfo);
 455
 456         return ret;
 457 }
 458
 459 /*
 460  * Probe routine for each detected JobR subsystem. It assumes that
 461  * property detection was picked up externally.
 462  */
 463 int caam_jr_probe(struct platform_device *pdev, struct device_node *np,
 464                   int ring)
 465 {
 466         struct device *ctrldev, *jrdev;
 467         struct platform_device *jr_pdev;
 468         struct caam_drv_private *ctrlpriv;
 469         struct caam_drv_private_jr *jrpriv;
 470         u32 *jroffset;
 471         int error;
 472
 473         ctrldev = &pdev->dev;
 474         ctrlpriv = dev_get_drvdata(ctrldev);
 475
 476         jrpriv = kmalloc(sizeof(struct caam_drv_private_jr),
 477                          GFP_KERNEL);
 478         if (jrpriv == NULL) {
 479                 dev_err(ctrldev, "can't alloc private mem for job ring %d\n",
 480                         ring);
 481                 return -ENOMEM;
 482         }
 483         jrpriv->parentdev = ctrldev; /* point back to parent */
 484         jrpriv->ridx = ring; /* save ring identity relative to detection */
 485
 486         /*
 487          * Derive a pointer to the detected JobRs regs
 488          * Driver has already iomapped the entire space, we just
 489          * need to add in the offset to this JobR. Don't know if I
 490          * like this long-term, but it'll run
 491          */
 492         jroffset = (u32 *)of_get_property(np, "reg", NULL);
 493         jrpriv->rregs = (struct caam_job_ring __iomem *)((void *)ctrlpriv->ctrl
 494                                                          + *jroffset);
 495
 496         /* Build a local dev for each detected queue */
 497         jr_pdev = of_platform_device_create(np, NULL, ctrldev);
 498         if (jr_pdev == NULL) {
 499                 kfree(jrpriv);
 500                 return -EINVAL;
 501         }
 502         jrdev = &jr_pdev->dev;
 503         dev_set_drvdata(jrdev, jrpriv);
 504         ctrlpriv->jrdev[ring] = jrdev;
 505
 506         /* Identify the interrupt */
 507         jrpriv->irq = of_irq_to_resource(np, 0, NULL);
 508
 509         /* Now do the platform independent part */
 510         error = caam_jr_init(jrdev); /* now turn on hardware */
 511         if (error) {
 512                 kfree(jrpriv);
 513                 return error;
 514         }
 515
 516         return error;
 517 }