linux/drivers/crypto/caam/jr.c
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   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
  17struct 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
  23static struct jr_driver_data driver_data;
  24
  25static 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 */
  68int 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
  93static 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 */
 125static 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 */
 163static 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                        smp_read_barrier_depends();
 185
 186                        if (jrp->outring[hw_idx].desc ==
 187                            jrp->entinfo[sw_idx].desc_addr_dma)
 188                                break; /* found */
 189                }
 190                /* we should never fail to find a matching descriptor */
 191                BUG_ON(CIRC_CNT(head, tail + i, JOBR_DEPTH) <= 0);
 192
 193                /* Unmap just-run descriptor so we can post-process */
 194                dma_unmap_single(dev, jrp->outring[hw_idx].desc,
 195                                 jrp->entinfo[sw_idx].desc_size,
 196                                 DMA_TO_DEVICE);
 197
 198                /* mark completed, avoid matching on a recycled desc addr */
 199                jrp->entinfo[sw_idx].desc_addr_dma = 0;
 200
 201                /* Stash callback params for use outside of lock */
 202                usercall = jrp->entinfo[sw_idx].callbk;
 203                userarg = jrp->entinfo[sw_idx].cbkarg;
 204                userdesc = jrp->entinfo[sw_idx].desc_addr_virt;
 205                userstatus = jrp->outring[hw_idx].jrstatus;
 206
 207                /* set done */
 208                wr_reg32(&jrp->rregs->outring_rmvd, 1);
 209
 210                jrp->out_ring_read_index = (jrp->out_ring_read_index + 1) &
 211                                           (JOBR_DEPTH - 1);
 212
 213                /*
 214                 * if this job completed out-of-order, do not increment
 215                 * the tail.  Otherwise, increment tail by 1 plus the
 216                 * number of subsequent jobs already completed out-of-order
 217                 */
 218                if (sw_idx == tail) {
 219                        do {
 220                                tail = (tail + 1) & (JOBR_DEPTH - 1);
 221                                smp_read_barrier_depends();
 222                        } while (CIRC_CNT(head, tail, JOBR_DEPTH) >= 1 &&
 223                                 jrp->entinfo[tail].desc_addr_dma == 0);
 224
 225                        jrp->tail = tail;
 226                }
 227
 228                spin_unlock(&jrp->outlock);
 229
 230                /* Finally, execute user's callback */
 231                usercall(dev, userdesc, userstatus, userarg);
 232        }
 233
 234        /* reenable / unmask IRQs */
 235        clrbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
 236}
 237
 238/**
 239 * caam_jr_alloc() - Alloc a job ring for someone to use as needed.
 240 *
 241 * returns :  pointer to the newly allocated physical
 242 *            JobR dev can be written to if successful.
 243 **/
 244struct device *caam_jr_alloc(void)
 245{
 246        struct caam_drv_private_jr *jrpriv, *min_jrpriv = NULL;
 247        struct device *dev = NULL;
 248        int min_tfm_cnt = INT_MAX;
 249        int tfm_cnt;
 250
 251        spin_lock(&driver_data.jr_alloc_lock);
 252
 253        if (list_empty(&driver_data.jr_list)) {
 254                spin_unlock(&driver_data.jr_alloc_lock);
 255                return ERR_PTR(-ENODEV);
 256        }
 257
 258        list_for_each_entry(jrpriv, &driver_data.jr_list, list_node) {
 259                tfm_cnt = atomic_read(&jrpriv->tfm_count);
 260                if (tfm_cnt < min_tfm_cnt) {
 261                        min_tfm_cnt = tfm_cnt;
 262                        min_jrpriv = jrpriv;
 263                }
 264                if (!min_tfm_cnt)
 265                        break;
 266        }
 267
 268        if (min_jrpriv) {
 269                atomic_inc(&min_jrpriv->tfm_count);
 270                dev = min_jrpriv->dev;
 271        }
 272        spin_unlock(&driver_data.jr_alloc_lock);
 273
 274        return dev;
 275}
 276EXPORT_SYMBOL(caam_jr_alloc);
 277
 278/**
 279 * caam_jr_free() - Free the Job Ring
 280 * @rdev     - points to the dev that identifies the Job ring to
 281 *             be released.
 282 **/
 283void caam_jr_free(struct device *rdev)
 284{
 285        struct caam_drv_private_jr *jrpriv = dev_get_drvdata(rdev);
 286
 287        atomic_dec(&jrpriv->tfm_count);
 288}
 289EXPORT_SYMBOL(caam_jr_free);
 290
 291/**
 292 * caam_jr_enqueue() - Enqueue a job descriptor head. Returns 0 if OK,
 293 * -EBUSY if the queue is full, -EIO if it cannot map the caller's
 294 * descriptor.
 295 * @dev:  device of the job ring to be used. This device should have
 296 *        been assigned prior by caam_jr_register().
 297 * @desc: points to a job descriptor that execute our request. All
 298 *        descriptors (and all referenced data) must be in a DMAable
 299 *        region, and all data references must be physical addresses
 300 *        accessible to CAAM (i.e. within a PAMU window granted
 301 *        to it).
 302 * @cbk:  pointer to a callback function to be invoked upon completion
 303 *        of this request. This has the form:
 304 *        callback(struct device *dev, u32 *desc, u32 stat, void *arg)
 305 *        where:
 306 *        @dev:    contains the job ring device that processed this
 307 *                 response.
 308 *        @desc:   descriptor that initiated the request, same as
 309 *                 "desc" being argued to caam_jr_enqueue().
 310 *        @status: untranslated status received from CAAM. See the
 311 *                 reference manual for a detailed description of
 312 *                 error meaning, or see the JRSTA definitions in the
 313 *                 register header file
 314 *        @areq:   optional pointer to an argument passed with the
 315 *                 original request
 316 * @areq: optional pointer to a user argument for use at callback
 317 *        time.
 318 **/
 319int caam_jr_enqueue(struct device *dev, u32 *desc,
 320                    void (*cbk)(struct device *dev, u32 *desc,
 321                                u32 status, void *areq),
 322                    void *areq)
 323{
 324        struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 325        struct caam_jrentry_info *head_entry;
 326        int head, tail, desc_size;
 327        dma_addr_t desc_dma;
 328
 329        desc_size = (*desc & HDR_JD_LENGTH_MASK) * sizeof(u32);
 330        desc_dma = dma_map_single(dev, desc, desc_size, DMA_TO_DEVICE);
 331        if (dma_mapping_error(dev, desc_dma)) {
 332                dev_err(dev, "caam_jr_enqueue(): can't map jobdesc\n");
 333                return -EIO;
 334        }
 335
 336        spin_lock_bh(&jrp->inplock);
 337
 338        head = jrp->head;
 339        tail = ACCESS_ONCE(jrp->tail);
 340
 341        if (!rd_reg32(&jrp->rregs->inpring_avail) ||
 342            CIRC_SPACE(head, tail, JOBR_DEPTH) <= 0) {
 343                spin_unlock_bh(&jrp->inplock);
 344                dma_unmap_single(dev, desc_dma, desc_size, DMA_TO_DEVICE);
 345                return -EBUSY;
 346        }
 347
 348        head_entry = &jrp->entinfo[head];
 349        head_entry->desc_addr_virt = desc;
 350        head_entry->desc_size = desc_size;
 351        head_entry->callbk = (void *)cbk;
 352        head_entry->cbkarg = areq;
 353        head_entry->desc_addr_dma = desc_dma;
 354
 355        jrp->inpring[jrp->inp_ring_write_index] = desc_dma;
 356
 357        smp_wmb();
 358
 359        jrp->inp_ring_write_index = (jrp->inp_ring_write_index + 1) &
 360                                    (JOBR_DEPTH - 1);
 361        jrp->head = (head + 1) & (JOBR_DEPTH - 1);
 362
 363        wr_reg32(&jrp->rregs->inpring_jobadd, 1);
 364
 365        spin_unlock_bh(&jrp->inplock);
 366
 367        return 0;
 368}
 369EXPORT_SYMBOL(caam_jr_enqueue);
 370
 371/*
 372 * Init JobR independent of platform property detection
 373 */
 374static int caam_jr_init(struct device *dev)
 375{
 376        struct caam_drv_private_jr *jrp;
 377        dma_addr_t inpbusaddr, outbusaddr;
 378        int i, error;
 379
 380        jrp = dev_get_drvdata(dev);
 381
 382        tasklet_init(&jrp->irqtask, caam_jr_dequeue, (unsigned long)dev);
 383
 384        /* Connect job ring interrupt handler. */
 385        error = request_irq(jrp->irq, caam_jr_interrupt, IRQF_SHARED,
 386                            dev_name(dev), dev);
 387        if (error) {
 388                dev_err(dev, "can't connect JobR %d interrupt (%d)\n",
 389                        jrp->ridx, jrp->irq);
 390                irq_dispose_mapping(jrp->irq);
 391                jrp->irq = 0;
 392                return -EINVAL;
 393        }
 394
 395        error = caam_reset_hw_jr(dev);
 396        if (error)
 397                return error;
 398
 399        jrp->inpring = dma_alloc_coherent(dev, sizeof(dma_addr_t) * JOBR_DEPTH,
 400                                          &inpbusaddr, GFP_KERNEL);
 401
 402        jrp->outring = dma_alloc_coherent(dev, sizeof(struct jr_outentry) *
 403                                          JOBR_DEPTH, &outbusaddr, GFP_KERNEL);
 404
 405        jrp->entinfo = kzalloc(sizeof(struct caam_jrentry_info) * JOBR_DEPTH,
 406                               GFP_KERNEL);
 407
 408        if ((jrp->inpring == NULL) || (jrp->outring == NULL) ||
 409            (jrp->entinfo == NULL)) {
 410                dev_err(dev, "can't allocate job rings for %d\n",
 411                        jrp->ridx);
 412                return -ENOMEM;
 413        }
 414
 415        for (i = 0; i < JOBR_DEPTH; i++)
 416                jrp->entinfo[i].desc_addr_dma = !0;
 417
 418        /* Setup rings */
 419        jrp->inp_ring_write_index = 0;
 420        jrp->out_ring_read_index = 0;
 421        jrp->head = 0;
 422        jrp->tail = 0;
 423
 424        wr_reg64(&jrp->rregs->inpring_base, inpbusaddr);
 425        wr_reg64(&jrp->rregs->outring_base, outbusaddr);
 426        wr_reg32(&jrp->rregs->inpring_size, JOBR_DEPTH);
 427        wr_reg32(&jrp->rregs->outring_size, JOBR_DEPTH);
 428
 429        jrp->ringsize = JOBR_DEPTH;
 430
 431        spin_lock_init(&jrp->inplock);
 432        spin_lock_init(&jrp->outlock);
 433
 434        /* Select interrupt coalescing parameters */
 435        setbits32(&jrp->rregs->rconfig_lo, JOBR_INTC |
 436                  (JOBR_INTC_COUNT_THLD << JRCFG_ICDCT_SHIFT) |
 437                  (JOBR_INTC_TIME_THLD << JRCFG_ICTT_SHIFT));
 438
 439        return 0;
 440}
 441
 442
 443/*
 444 * Probe routine for each detected JobR subsystem.
 445 */
 446static int caam_jr_probe(struct platform_device *pdev)
 447{
 448        struct device *jrdev;
 449        struct device_node *nprop;
 450        struct caam_job_ring __iomem *ctrl;
 451        struct caam_drv_private_jr *jrpriv;
 452        static int total_jobrs;
 453        int error;
 454
 455        jrdev = &pdev->dev;
 456        jrpriv = devm_kmalloc(jrdev, sizeof(struct caam_drv_private_jr),
 457                              GFP_KERNEL);
 458        if (!jrpriv)
 459                return -ENOMEM;
 460
 461        dev_set_drvdata(jrdev, jrpriv);
 462
 463        /* save ring identity relative to detection */
 464        jrpriv->ridx = total_jobrs++;
 465
 466        nprop = pdev->dev.of_node;
 467        /* Get configuration properties from device tree */
 468        /* First, get register page */
 469        ctrl = of_iomap(nprop, 0);
 470        if (!ctrl) {
 471                dev_err(jrdev, "of_iomap() failed\n");
 472                return -ENOMEM;
 473        }
 474
 475        jrpriv->rregs = (struct caam_job_ring __force *)ctrl;
 476
 477        if (sizeof(dma_addr_t) == sizeof(u64))
 478                if (of_device_is_compatible(nprop, "fsl,sec-v5.0-job-ring"))
 479                        dma_set_mask(jrdev, DMA_BIT_MASK(40));
 480                else
 481                        dma_set_mask(jrdev, DMA_BIT_MASK(36));
 482        else
 483                dma_set_mask(jrdev, DMA_BIT_MASK(32));
 484
 485        /* Identify the interrupt */
 486        jrpriv->irq = irq_of_parse_and_map(nprop, 0);
 487
 488        /* Now do the platform independent part */
 489        error = caam_jr_init(jrdev); /* now turn on hardware */
 490        if (error)
 491                return error;
 492
 493        jrpriv->dev = jrdev;
 494        spin_lock(&driver_data.jr_alloc_lock);
 495        list_add_tail(&jrpriv->list_node, &driver_data.jr_list);
 496        spin_unlock(&driver_data.jr_alloc_lock);
 497
 498        atomic_set(&jrpriv->tfm_count, 0);
 499
 500        return 0;
 501}
 502
 503static struct of_device_id caam_jr_match[] = {
 504        {
 505                .compatible = "fsl,sec-v4.0-job-ring",
 506        },
 507        {
 508                .compatible = "fsl,sec4.0-job-ring",
 509        },
 510        {},
 511};
 512MODULE_DEVICE_TABLE(of, caam_jr_match);
 513
 514static struct platform_driver caam_jr_driver = {
 515        .driver = {
 516                .name = "caam_jr",
 517                .owner = THIS_MODULE,
 518                .of_match_table = caam_jr_match,
 519        },
 520        .probe       = caam_jr_probe,
 521        .remove      = caam_jr_remove,
 522};
 523
 524static int __init jr_driver_init(void)
 525{
 526        spin_lock_init(&driver_data.jr_alloc_lock);
 527        INIT_LIST_HEAD(&driver_data.jr_list);
 528        return platform_driver_register(&caam_jr_driver);
 529}
 530
 531static void __exit jr_driver_exit(void)
 532{
 533        platform_driver_unregister(&caam_jr_driver);
 534}
 535
 536module_init(jr_driver_init);
 537module_exit(jr_driver_exit);
 538
 539MODULE_LICENSE("GPL");
 540MODULE_DESCRIPTION("FSL CAAM JR request backend");
 541MODULE_AUTHOR("Freescale Semiconductor - NMG/STC");
 542
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