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 "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
  62         spin_lock_bh(&jrp->outlock);
  63
  64         head = ACCESS_ONCE(jrp->head);
  65         sw_idx = tail = jrp->tail;
  66
  67         while (CIRC_CNT(head, tail, JOBR_DEPTH) >= 1 &&
  68                rd_reg32(&jrp->rregs->outring_used)) {
  69
  70                 hw_idx = jrp->out_ring_read_index;
  71                 for (i = 0; CIRC_CNT(head, tail + i, JOBR_DEPTH) >= 1; i++) {
  72                         sw_idx = (tail + i) & (JOBR_DEPTH - 1);
  73
  74                         smp_read_barrier_depends();
  75
  76                         if (jrp->outring[hw_idx].desc ==
  77                             jrp->entinfo[sw_idx].desc_addr_dma)
  78                                 break; /* found */
  79                 }
  80                 /* we should never fail to find a matching descriptor */
  81                 BUG_ON(CIRC_CNT(head, tail + i, JOBR_DEPTH) <= 0);
  82
  83                 /* Unmap just-run descriptor so we can post-process */
  84                 dma_unmap_single(dev, jrp->outring[hw_idx].desc,
  85                                  jrp->entinfo[sw_idx].desc_size,
  86                                  DMA_TO_DEVICE);
  87
  88                 /* mark completed, avoid matching on a recycled desc addr */
  89                 jrp->entinfo[sw_idx].desc_addr_dma = 0;
  90
  91                 /* Stash callback params for use outside of lock */
  92                 usercall = jrp->entinfo[sw_idx].callbk;
  93                 userarg = jrp->entinfo[sw_idx].cbkarg;
  94                 userdesc = jrp->entinfo[sw_idx].desc_addr_virt;
  95                 userstatus = jrp->outring[hw_idx].jrstatus;
  96
  97                 smp_mb();
  98
  99                 jrp->out_ring_read_index = (jrp->out_ring_read_index + 1) &
 100                                            (JOBR_DEPTH - 1);
 101
 102                 /*
 103                  * if this job completed out-of-order, do not increment
 104                  * the tail.  Otherwise, increment tail by 1 plus the
 105                  * number of subsequent jobs already completed out-of-order
 106                  */
 107                 if (sw_idx == tail) {
 108                         do {
 109                                 tail = (tail + 1) & (JOBR_DEPTH - 1);
 110                                 smp_read_barrier_depends();
 111                         } while (CIRC_CNT(head, tail, JOBR_DEPTH) >= 1 &&
 112                                  jrp->entinfo[tail].desc_addr_dma == 0);
 113
 114                         jrp->tail = tail;
 115                 }
 116
 117                 /* set done */
 118                 wr_reg32(&jrp->rregs->outring_rmvd, 1);
 119
 120                 spin_unlock_bh(&jrp->outlock);
 121
 122                 /* Finally, execute user's callback */
 123                 usercall(dev, userdesc, userstatus, userarg);
 124
 125                 spin_lock_bh(&jrp->outlock);
 126
 127                 head = ACCESS_ONCE(jrp->head);
 128                 sw_idx = tail = jrp->tail;
 129         }
 130
 131         spin_unlock_bh(&jrp->outlock);
 132
 133         /* reenable / unmask IRQs */
 134         clrbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
 135 }
 136
 137 /**
 138  * caam_jr_register() - Alloc a ring for someone to use as needed. Returns
 139  * an ordinal of the rings allocated, else returns -ENODEV if no rings
 140  * are available.
 141  * @ctrldev: points to the controller level dev (parent) that
 142  *           owns rings available for use.
 143  * @dev:     points to where a pointer to the newly allocated queue's
 144  *           dev can be written to if successful.
 145  **/
 146 int caam_jr_register(struct device *ctrldev, struct device **rdev)
 147 {
 148         struct caam_drv_private *ctrlpriv = dev_get_drvdata(ctrldev);
 149         struct caam_drv_private_jr *jrpriv = NULL;
 150         int ring;
 151
 152         /* Lock, if free ring - assign, unlock */
 153         spin_lock(&ctrlpriv->jr_alloc_lock);
 154         for (ring = 0; ring < ctrlpriv->total_jobrs; ring++) {
 155                 jrpriv = dev_get_drvdata(ctrlpriv->jrdev[ring]);
 156                 if (jrpriv->assign == JOBR_UNASSIGNED) {
 157                         jrpriv->assign = JOBR_ASSIGNED;
 158                         *rdev = ctrlpriv->jrdev[ring];
 159                         spin_unlock(&ctrlpriv->jr_alloc_lock);
 160                         return ring;
 161                 }
 162         }
 163
 164         /* If assigned, write dev where caller needs it */
 165         spin_unlock(&ctrlpriv->jr_alloc_lock);
 166         *rdev = NULL;
 167
 168         return -ENODEV;
 169 }
 170 EXPORT_SYMBOL(caam_jr_register);
 171
 172 /**
 173  * caam_jr_deregister() - Deregister an API and release the queue.
 174  * Returns 0 if OK, -EBUSY if queue still contains pending entries
 175  * or unprocessed results at the time of the call
 176  * @dev     - points to the dev that identifies the queue to
 177  *            be released.
 178  **/
 179 int caam_jr_deregister(struct device *rdev)
 180 {
 181         struct caam_drv_private_jr *jrpriv = dev_get_drvdata(rdev);
 182         struct caam_drv_private *ctrlpriv;
 183
 184         /* Get the owning controller's private space */
 185         ctrlpriv = dev_get_drvdata(jrpriv->parentdev);
 186
 187         /*
 188          * Make sure ring empty before release
 189          */
 190         if (rd_reg32(&jrpriv->rregs->outring_used) ||
 191             (rd_reg32(&jrpriv->rregs->inpring_avail) != JOBR_DEPTH))
 192                 return -EBUSY;
 193
 194         /* Release ring */
 195         spin_lock(&ctrlpriv->jr_alloc_lock);
 196         jrpriv->assign = JOBR_UNASSIGNED;
 197         spin_unlock(&ctrlpriv->jr_alloc_lock);
 198
 199         return 0;
 200 }
 201 EXPORT_SYMBOL(caam_jr_deregister);
 202
 203 /**
 204  * caam_jr_enqueue() - Enqueue a job descriptor head. Returns 0 if OK,
 205  * -EBUSY if the queue is full, -EIO if it cannot map the caller's
 206  * descriptor.
 207  * @dev:  device of the job ring to be used. This device should have
 208  *        been assigned prior by caam_jr_register().
 209  * @desc: points to a job descriptor that execute our request. All
 210  *        descriptors (and all referenced data) must be in a DMAable
 211  *        region, and all data references must be physical addresses
 212  *        accessible to CAAM (i.e. within a PAMU window granted
 213  *        to it).
 214  * @cbk:  pointer to a callback function to be invoked upon completion
 215  *        of this request. This has the form:
 216  *        callback(struct device *dev, u32 *desc, u32 stat, void *arg)
 217  *        where:
 218  *        @dev:    contains the job ring device that processed this
 219  *                 response.
 220  *        @desc:   descriptor that initiated the request, same as
 221  *                 "desc" being argued to caam_jr_enqueue().
 222  *        @status: untranslated status received from CAAM. See the
 223  *                 reference manual for a detailed description of
 224  *                 error meaning, or see the JRSTA definitions in the
 225  *                 register header file
 226  *        @areq:   optional pointer to an argument passed with the
 227  *                 original request
 228  * @areq: optional pointer to a user argument for use at callback
 229  *        time.
 230  **/
 231 int caam_jr_enqueue(struct device *dev, u32 *desc,
 232                     void (*cbk)(struct device *dev, u32 *desc,
 233                                 u32 status, void *areq),
 234                     void *areq)
 235 {
 236         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 237         struct caam_jrentry_info *head_entry;
 238         int head, tail, desc_size;
 239         dma_addr_t desc_dma;
 240
 241         desc_size = (*desc & HDR_JD_LENGTH_MASK) * sizeof(u32);
 242         desc_dma = dma_map_single(dev, desc, desc_size, DMA_TO_DEVICE);
 243         if (dma_mapping_error(dev, desc_dma)) {
 244                 dev_err(dev, "caam_jr_enqueue(): can't map jobdesc\n");
 245                 return -EIO;
 246         }
 247
 248         spin_lock(&jrp->inplock);
 249
 250         head = jrp->head;
 251         tail = ACCESS_ONCE(jrp->tail);
 252
 253         if (!rd_reg32(&jrp->rregs->inpring_avail) ||
 254             CIRC_SPACE(head, tail, JOBR_DEPTH) <= 0) {
 255                 spin_unlock(&jrp->inplock);
 256                 dma_unmap_single(dev, desc_dma, desc_size, DMA_TO_DEVICE);
 257                 return -EBUSY;
 258         }
 259
 260         head_entry = &jrp->entinfo[head];
 261         head_entry->desc_addr_virt = desc;
 262         head_entry->desc_size = desc_size;
 263         head_entry->callbk = (void *)cbk;
 264         head_entry->cbkarg = areq;
 265         head_entry->desc_addr_dma = desc_dma;
 266
 267         jrp->inpring[jrp->inp_ring_write_index] = desc_dma;
 268
 269         smp_wmb();
 270
 271         jrp->inp_ring_write_index = (jrp->inp_ring_write_index + 1) &
 272                                     (JOBR_DEPTH - 1);
 273         jrp->head = (head + 1) & (JOBR_DEPTH - 1);
 274
 275         wmb();
 276
 277         wr_reg32(&jrp->rregs->inpring_jobadd, 1);
 278
 279         spin_unlock(&jrp->inplock);
 280
 281         return 0;
 282 }
 283 EXPORT_SYMBOL(caam_jr_enqueue);
 284
 285 static int caam_reset_hw_jr(struct device *dev)
 286 {
 287         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 288         unsigned int timeout = 100000;
 289
 290         /*
 291          * mask interrupts since we are going to poll
 292          * for reset completion status
 293          */
 294         setbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
 295
 296         /* initiate flush (required prior to reset) */
 297         wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
 298         while (((rd_reg32(&jrp->rregs->jrintstatus) & JRINT_ERR_HALT_MASK) ==
 299                 JRINT_ERR_HALT_INPROGRESS) && --timeout)
 300                 cpu_relax();
 301
 302         if ((rd_reg32(&jrp->rregs->jrintstatus) & JRINT_ERR_HALT_MASK) !=
 303             JRINT_ERR_HALT_COMPLETE || timeout == 0) {
 304                 dev_err(dev, "failed to flush job ring %d\n", jrp->ridx);
 305                 return -EIO;
 306         }
 307
 308         /* initiate reset */
 309         timeout = 100000;
 310         wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
 311         while ((rd_reg32(&jrp->rregs->jrcommand) & JRCR_RESET) && --timeout)
 312                 cpu_relax();
 313
 314         if (timeout == 0) {
 315                 dev_err(dev, "failed to reset job ring %d\n", jrp->ridx);
 316                 return -EIO;
 317         }
 318
 319         /* unmask interrupts */
 320         clrbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
 321
 322         return 0;
 323 }
 324
 325 /*
 326  * Init JobR independent of platform property detection
 327  */
 328 static int caam_jr_init(struct device *dev)
 329 {
 330         struct caam_drv_private_jr *jrp;
 331         dma_addr_t inpbusaddr, outbusaddr;
 332         int i, error;
 333
 334         jrp = dev_get_drvdata(dev);
 335
 336         /* Connect job ring interrupt handler. */
 337         for_each_possible_cpu(i)
 338                 tasklet_init(&jrp->irqtask[i], caam_jr_dequeue,
 339                              (unsigned long)dev);
 340
 341         error = request_irq(jrp->irq, caam_jr_interrupt, IRQF_SHARED,
 342                             "caam-jobr", dev);
 343         if (error) {
 344                 dev_err(dev, "can't connect JobR %d interrupt (%d)\n",
 345                         jrp->ridx, jrp->irq);
 346                 irq_dispose_mapping(jrp->irq);
 347                 jrp->irq = 0;
 348                 return -EINVAL;
 349         }
 350
 351         error = caam_reset_hw_jr(dev);
 352         if (error)
 353                 return error;
 354
 355         jrp->inpring = kzalloc(sizeof(dma_addr_t) * JOBR_DEPTH,
 356                                GFP_KERNEL | GFP_DMA);
 357         jrp->outring = kzalloc(sizeof(struct jr_outentry) *
 358                                JOBR_DEPTH, GFP_KERNEL | GFP_DMA);
 359
 360         jrp->entinfo = kzalloc(sizeof(struct caam_jrentry_info) * JOBR_DEPTH,
 361                                GFP_KERNEL);
 362
 363         if ((jrp->inpring == NULL) || (jrp->outring == NULL) ||
 364             (jrp->entinfo == NULL)) {
 365                 dev_err(dev, "can't allocate job rings for %d\n",
 366                         jrp->ridx);
 367                 return -ENOMEM;
 368         }
 369
 370         for (i = 0; i < JOBR_DEPTH; i++)
 371                 jrp->entinfo[i].desc_addr_dma = !0;
 372
 373         /* Setup rings */
 374         inpbusaddr = dma_map_single(dev, jrp->inpring,
 375                                     sizeof(dma_addr_t) * JOBR_DEPTH,
 376                                     DMA_BIDIRECTIONAL);
 377         if (dma_mapping_error(dev, inpbusaddr)) {
 378                 dev_err(dev, "caam_jr_init(): can't map input ring\n");
 379                 kfree(jrp->inpring);
 380                 kfree(jrp->outring);
 381                 kfree(jrp->entinfo);
 382                 return -EIO;
 383         }
 384
 385         outbusaddr = dma_map_single(dev, jrp->outring,
 386                                     sizeof(struct jr_outentry) * JOBR_DEPTH,
 387                                     DMA_BIDIRECTIONAL);
 388         if (dma_mapping_error(dev, outbusaddr)) {
 389                 dev_err(dev, "caam_jr_init(): can't map output ring\n");
 390                 dma_unmap_single(dev, inpbusaddr,
 391                                  sizeof(dma_addr_t) * JOBR_DEPTH,
 392                                  DMA_BIDIRECTIONAL);
 393                 kfree(jrp->inpring);
 394                 kfree(jrp->outring);
 395                 kfree(jrp->entinfo);
 396                 return -EIO;
 397         }
 398
 399         jrp->inp_ring_write_index = 0;
 400         jrp->out_ring_read_index = 0;
 401         jrp->head = 0;
 402         jrp->tail = 0;
 403
 404         wr_reg64(&jrp->rregs->inpring_base, inpbusaddr);
 405         wr_reg64(&jrp->rregs->outring_base, outbusaddr);
 406         wr_reg32(&jrp->rregs->inpring_size, JOBR_DEPTH);
 407         wr_reg32(&jrp->rregs->outring_size, JOBR_DEPTH);
 408
 409         jrp->ringsize = JOBR_DEPTH;
 410
 411         spin_lock_init(&jrp->inplock);
 412         spin_lock_init(&jrp->outlock);
 413
 414         /* Select interrupt coalescing parameters */
 415         setbits32(&jrp->rregs->rconfig_lo, JOBR_INTC |
 416                   (JOBR_INTC_COUNT_THLD << JRCFG_ICDCT_SHIFT) |
 417                   (JOBR_INTC_TIME_THLD << JRCFG_ICTT_SHIFT));
 418
 419         jrp->assign = JOBR_UNASSIGNED;
 420         return 0;
 421 }
 422
 423 /*
 424  * Shutdown JobR independent of platform property code
 425  */
 426 int caam_jr_shutdown(struct device *dev)
 427 {
 428         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 429         dma_addr_t inpbusaddr, outbusaddr;
 430         int ret, i;
 431
 432         ret = caam_reset_hw_jr(dev);
 433
 434         for_each_possible_cpu(i)
 435                 tasklet_kill(&jrp->irqtask[i]);
 436
 437         /* Release interrupt */
 438         free_irq(jrp->irq, dev);
 439
 440         /* Free rings */
 441         inpbusaddr = rd_reg64(&jrp->rregs->inpring_base);
 442         outbusaddr = rd_reg64(&jrp->rregs->outring_base);
 443         dma_unmap_single(dev, outbusaddr,
 444                          sizeof(struct jr_outentry) * JOBR_DEPTH,
 445                          DMA_BIDIRECTIONAL);
 446         dma_unmap_single(dev, inpbusaddr, sizeof(dma_addr_t) * JOBR_DEPTH,
 447                          DMA_BIDIRECTIONAL);
 448         kfree(jrp->outring);
 449         kfree(jrp->inpring);
 450         kfree(jrp->entinfo);
 451
 452         return ret;
 453 }
 454
 455 /*
 456  * Probe routine for each detected JobR subsystem. It assumes that
 457  * property detection was picked up externally.
 458  */
 459 int caam_jr_probe(struct platform_device *pdev, struct device_node *np,
 460                   int ring)
 461 {
 462         struct device *ctrldev, *jrdev;
 463         struct platform_device *jr_pdev;
 464         struct caam_drv_private *ctrlpriv;
 465         struct caam_drv_private_jr *jrpriv;
 466         u32 *jroffset;
 467         int error;
 468
 469         ctrldev = &pdev->dev;
 470         ctrlpriv = dev_get_drvdata(ctrldev);
 471
 472         jrpriv = kmalloc(sizeof(struct caam_drv_private_jr),
 473                          GFP_KERNEL);
 474         if (jrpriv == NULL) {
 475                 dev_err(ctrldev, "can't alloc private mem for job ring %d\n",
 476                         ring);
 477                 return -ENOMEM;
 478         }
 479         jrpriv->parentdev = ctrldev; /* point back to parent */
 480         jrpriv->ridx = ring; /* save ring identity relative to detection */
 481
 482         /*
 483          * Derive a pointer to the detected JobRs regs
 484          * Driver has already iomapped the entire space, we just
 485          * need to add in the offset to this JobR. Don't know if I
 486          * like this long-term, but it'll run
 487          */
 488         jroffset = (u32 *)of_get_property(np, "reg", NULL);
 489         jrpriv->rregs = (struct caam_job_ring __iomem *)((void *)ctrlpriv->ctrl
 490                                                          + *jroffset);
 491
 492         /* Build a local dev for each detected queue */
 493         jr_pdev = of_platform_device_create(np, NULL, ctrldev);
 494         if (jr_pdev == NULL) {
 495                 kfree(jrpriv);
 496                 return -EINVAL;
 497         }
 498         jrdev = &jr_pdev->dev;
 499         dev_set_drvdata(jrdev, jrpriv);
 500         ctrlpriv->jrdev[ring] = jrdev;
 501
 502         if (sizeof(dma_addr_t) == sizeof(u64))
 503                 if (of_device_is_compatible(np, "fsl,sec-v5.0-job-ring"))
 504                         dma_set_mask(jrdev, DMA_BIT_MASK(40));
 505                 else
 506                         dma_set_mask(jrdev, DMA_BIT_MASK(36));
 507         else
 508                 dma_set_mask(jrdev, DMA_BIT_MASK(32));
 509
 510         /* Identify the interrupt */
 511         jrpriv->irq = of_irq_to_resource(np, 0, NULL);
 512
 513         /* Now do the platform independent part */
 514         error = caam_jr_init(jrdev); /* now turn on hardware */
 515         if (error) {
 516                 kfree(jrpriv);
 517                 return error;
 518         }
 519
 520         return error;
 521 }