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