drivers/dma/fsl-edma.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * drivers/dma/fsl-edma.c
   4  *
   5  * Copyright 2013-2014 Freescale Semiconductor, Inc.
   6  *
   7  * Driver for the Freescale eDMA engine with flexible channel multiplexing
   8  * capability for DMA request sources. The eDMA block can be found on some
   9  * Vybrid and Layerscape SoCs.
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/clk.h>
  15 #include <linux/of.h>
  16 #include <linux/of_device.h>
  17 #include <linux/of_address.h>
  18 #include <linux/of_irq.h>
  19 #include <linux/of_dma.h>
  20 #include <linux/dma-mapping.h>
  21
  22 #include "fsl-edma-common.h"
  23
  24 static void fsl_edma_synchronize(struct dma_chan *chan)
  25 {
  26         struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
  27
  28         vchan_synchronize(&fsl_chan->vchan);
  29 }
  30
  31 static irqreturn_t fsl_edma_tx_handler(int irq, void *dev_id)
  32 {
  33         struct fsl_edma_engine *fsl_edma = dev_id;
  34         unsigned int intr, ch;
  35         struct edma_regs *regs = &fsl_edma->regs;
  36         struct fsl_edma_chan *fsl_chan;
  37
  38         intr = edma_readl(fsl_edma, regs->intl);
  39         if (!intr)
  40                 return IRQ_NONE;
  41
  42         for (ch = 0; ch < fsl_edma->n_chans; ch++) {
  43                 if (intr & (0x1 << ch)) {
  44                         edma_writeb(fsl_edma, EDMA_CINT_CINT(ch), regs->cint);
  45
  46                         fsl_chan = &fsl_edma->chans[ch];
  47
  48                         spin_lock(&fsl_chan->vchan.lock);
  49
  50                         if (!fsl_chan->edesc) {
  51                                 /* terminate_all called before */
  52                                 spin_unlock(&fsl_chan->vchan.lock);
  53                                 continue;
  54                         }
  55
  56                         if (!fsl_chan->edesc->iscyclic) {
  57                                 list_del(&fsl_chan->edesc->vdesc.node);
  58                                 vchan_cookie_complete(&fsl_chan->edesc->vdesc);
  59                                 fsl_chan->edesc = NULL;
  60                                 fsl_chan->status = DMA_COMPLETE;
  61                                 fsl_chan->idle = true;
  62                         } else {
  63                                 vchan_cyclic_callback(&fsl_chan->edesc->vdesc);
  64                         }
  65
  66                         if (!fsl_chan->edesc)
  67                                 fsl_edma_xfer_desc(fsl_chan);
  68
  69                         spin_unlock(&fsl_chan->vchan.lock);
  70                 }
  71         }
  72         return IRQ_HANDLED;
  73 }
  74
  75 static irqreturn_t fsl_edma_err_handler(int irq, void *dev_id)
  76 {
  77         struct fsl_edma_engine *fsl_edma = dev_id;
  78         unsigned int err, ch;
  79         struct edma_regs *regs = &fsl_edma->regs;
  80
  81         err = edma_readl(fsl_edma, regs->errl);
  82         if (!err)
  83                 return IRQ_NONE;
  84
  85         for (ch = 0; ch < fsl_edma->n_chans; ch++) {
  86                 if (err & (0x1 << ch)) {
  87                         fsl_edma_disable_request(&fsl_edma->chans[ch]);
  88                         edma_writeb(fsl_edma, EDMA_CERR_CERR(ch), regs->cerr);
  89                         fsl_edma->chans[ch].status = DMA_ERROR;
  90                         fsl_edma->chans[ch].idle = true;
  91                 }
  92         }
  93         return IRQ_HANDLED;
  94 }
  95
  96 static irqreturn_t fsl_edma_irq_handler(int irq, void *dev_id)
  97 {
  98         if (fsl_edma_tx_handler(irq, dev_id) == IRQ_HANDLED)
  99                 return IRQ_HANDLED;
 100
 101         return fsl_edma_err_handler(irq, dev_id);
 102 }
 103
 104 static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
 105                 struct of_dma *ofdma)
 106 {
 107         struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
 108         struct dma_chan *chan, *_chan;
 109         struct fsl_edma_chan *fsl_chan;
 110         u32 dmamux_nr = fsl_edma->drvdata->dmamuxs;
 111         unsigned long chans_per_mux = fsl_edma->n_chans / dmamux_nr;
 112
 113         if (dma_spec->args_count != 2)
 114                 return NULL;
 115
 116         mutex_lock(&fsl_edma->fsl_edma_mutex);
 117         list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels, device_node) {
 118                 if (chan->client_count)
 119                         continue;
 120                 if ((chan->chan_id / chans_per_mux) == dma_spec->args[0]) {
 121                         chan = dma_get_slave_channel(chan);
 122                         if (chan) {
 123                                 chan->device->privatecnt++;
 124                                 fsl_chan = to_fsl_edma_chan(chan);
 125                                 fsl_chan->slave_id = dma_spec->args[1];
 126                                 fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id,
 127                                                 true);
 128                                 mutex_unlock(&fsl_edma->fsl_edma_mutex);
 129                                 return chan;
 130                         }
 131                 }
 132         }
 133         mutex_unlock(&fsl_edma->fsl_edma_mutex);
 134         return NULL;
 135 }
 136
 137 static int
 138 fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
 139 {
 140         int ret;
 141
 142         fsl_edma->txirq = platform_get_irq_byname(pdev, "edma-tx");
 143         if (fsl_edma->txirq < 0)
 144                 return fsl_edma->txirq;
 145
 146         fsl_edma->errirq = platform_get_irq_byname(pdev, "edma-err");
 147         if (fsl_edma->errirq < 0)
 148                 return fsl_edma->errirq;
 149
 150         if (fsl_edma->txirq == fsl_edma->errirq) {
 151                 ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
 152                                 fsl_edma_irq_handler, 0, "eDMA", fsl_edma);
 153                 if (ret) {
 154                         dev_err(&pdev->dev, "Can't register eDMA IRQ.\n");
 155                         return ret;
 156                 }
 157         } else {
 158                 ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
 159                                 fsl_edma_tx_handler, 0, "eDMA tx", fsl_edma);
 160                 if (ret) {
 161                         dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n");
 162                         return ret;
 163                 }
 164
 165                 ret = devm_request_irq(&pdev->dev, fsl_edma->errirq,
 166                                 fsl_edma_err_handler, 0, "eDMA err", fsl_edma);
 167                 if (ret) {
 168                         dev_err(&pdev->dev, "Can't register eDMA err IRQ.\n");
 169                         return ret;
 170                 }
 171         }
 172
 173         return 0;
 174 }
 175
 176 static int
 177 fsl_edma2_irq_init(struct platform_device *pdev,
 178                    struct fsl_edma_engine *fsl_edma)
 179 {
 180         int i, ret, irq;
 181         int count;
 182
 183         count = platform_irq_count(pdev);
 184         dev_dbg(&pdev->dev, "%s Found %d interrupts\r\n", __func__, count);
 185         if (count <= 2) {
 186                 dev_err(&pdev->dev, "Interrupts in DTS not correct.\n");
 187                 return -EINVAL;
 188         }
 189         /*
 190          * 16 channel independent interrupts + 1 error interrupt on i.mx7ulp.
 191          * 2 channel share one interrupt, for example, ch0/ch16, ch1/ch17...
 192          * For now, just simply request irq without IRQF_SHARED flag, since 16
 193          * channels are enough on i.mx7ulp whose M4 domain own some peripherals.
 194          */
 195         for (i = 0; i < count; i++) {
 196                 irq = platform_get_irq(pdev, i);
 197                 if (irq < 0)
 198                         return -ENXIO;
 199
 200                 sprintf(fsl_edma->chans[i].chan_name, "eDMA2-CH%02d", i);
 201
 202                 /* The last IRQ is for eDMA err */
 203                 if (i == count - 1)
 204                         ret = devm_request_irq(&pdev->dev, irq,
 205                                                 fsl_edma_err_handler,
 206                                                 0, "eDMA2-ERR", fsl_edma);
 207                 else
 208                         ret = devm_request_irq(&pdev->dev, irq,
 209                                                 fsl_edma_tx_handler, 0,
 210                                                 fsl_edma->chans[i].chan_name,
 211                                                 fsl_edma);
 212                 if (ret)
 213                         return ret;
 214         }
 215
 216         return 0;
 217 }
 218
 219 static void fsl_edma_irq_exit(
 220                 struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
 221 {
 222         if (fsl_edma->txirq == fsl_edma->errirq) {
 223                 devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
 224         } else {
 225                 devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
 226                 devm_free_irq(&pdev->dev, fsl_edma->errirq, fsl_edma);
 227         }
 228 }
 229
 230 static void fsl_disable_clocks(struct fsl_edma_engine *fsl_edma, int nr_clocks)
 231 {
 232         int i;
 233
 234         for (i = 0; i < nr_clocks; i++)
 235                 clk_disable_unprepare(fsl_edma->muxclk[i]);
 236 }
 237
 238 static struct fsl_edma_drvdata vf610_data = {
 239         .version = v1,
 240         .dmamuxs = DMAMUX_NR,
 241         .setup_irq = fsl_edma_irq_init,
 242 };
 243
 244 static struct fsl_edma_drvdata ls1028a_data = {
 245         .version = v1,
 246         .dmamuxs = DMAMUX_NR,
 247         .mux_swap = true,
 248         .setup_irq = fsl_edma_irq_init,
 249 };
 250
 251 static struct fsl_edma_drvdata imx7ulp_data = {
 252         .version = v3,
 253         .dmamuxs = 1,
 254         .has_dmaclk = true,
 255         .setup_irq = fsl_edma2_irq_init,
 256 };
 257
 258 static const struct of_device_id fsl_edma_dt_ids[] = {
 259         { .compatible = "fsl,vf610-edma", .data = &vf610_data},
 260         { .compatible = "fsl,ls1028a-edma", .data = &ls1028a_data},
 261         { .compatible = "fsl,imx7ulp-edma", .data = &imx7ulp_data},
 262         { /* sentinel */ }
 263 };
 264 MODULE_DEVICE_TABLE(of, fsl_edma_dt_ids);
 265
 266 static int fsl_edma_probe(struct platform_device *pdev)
 267 {
 268         const struct of_device_id *of_id =
 269                         of_match_device(fsl_edma_dt_ids, &pdev->dev);
 270         struct device_node *np = pdev->dev.of_node;
 271         struct fsl_edma_engine *fsl_edma;
 272         const struct fsl_edma_drvdata *drvdata = NULL;
 273         struct fsl_edma_chan *fsl_chan;
 274         struct edma_regs *regs;
 275         struct resource *res;
 276         int len, chans;
 277         int ret, i;
 278
 279         if (of_id)
 280                 drvdata = of_id->data;
 281         if (!drvdata) {
 282                 dev_err(&pdev->dev, "unable to find driver data\n");
 283                 return -EINVAL;
 284         }
 285
 286         ret = of_property_read_u32(np, "dma-channels", &chans);
 287         if (ret) {
 288                 dev_err(&pdev->dev, "Can't get dma-channels.\n");
 289                 return ret;
 290         }
 291
 292         len = sizeof(*fsl_edma) + sizeof(*fsl_chan) * chans;
 293         fsl_edma = devm_kzalloc(&pdev->dev, len, GFP_KERNEL);
 294         if (!fsl_edma)
 295                 return -ENOMEM;
 296
 297         fsl_edma->drvdata = drvdata;
 298         fsl_edma->n_chans = chans;
 299         mutex_init(&fsl_edma->fsl_edma_mutex);
 300
 301         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 302         fsl_edma->membase = devm_ioremap_resource(&pdev->dev, res);
 303         if (IS_ERR(fsl_edma->membase))
 304                 return PTR_ERR(fsl_edma->membase);
 305
 306         fsl_edma_setup_regs(fsl_edma);
 307         regs = &fsl_edma->regs;
 308
 309         if (drvdata->has_dmaclk) {
 310                 fsl_edma->dmaclk = devm_clk_get(&pdev->dev, "dma");
 311                 if (IS_ERR(fsl_edma->dmaclk)) {
 312                         dev_err(&pdev->dev, "Missing DMA block clock.\n");
 313                         return PTR_ERR(fsl_edma->dmaclk);
 314                 }
 315
 316                 ret = clk_prepare_enable(fsl_edma->dmaclk);
 317                 if (ret) {
 318                         dev_err(&pdev->dev, "DMA clk block failed.\n");
 319                         return ret;
 320                 }
 321         }
 322
 323         for (i = 0; i < fsl_edma->drvdata->dmamuxs; i++) {
 324                 char clkname[32];
 325
 326                 res = platform_get_resource(pdev, IORESOURCE_MEM, 1 + i);
 327                 fsl_edma->muxbase[i] = devm_ioremap_resource(&pdev->dev, res);
 328                 if (IS_ERR(fsl_edma->muxbase[i])) {
 329                         /* on error: disable all previously enabled clks */
 330                         fsl_disable_clocks(fsl_edma, i);
 331                         return PTR_ERR(fsl_edma->muxbase[i]);
 332                 }
 333
 334                 sprintf(clkname, "dmamux%d", i);
 335                 fsl_edma->muxclk[i] = devm_clk_get(&pdev->dev, clkname);
 336                 if (IS_ERR(fsl_edma->muxclk[i])) {
 337                         dev_err(&pdev->dev, "Missing DMAMUX block clock.\n");
 338                         /* on error: disable all previously enabled clks */
 339                         fsl_disable_clocks(fsl_edma, i);
 340                         return PTR_ERR(fsl_edma->muxclk[i]);
 341                 }
 342
 343                 ret = clk_prepare_enable(fsl_edma->muxclk[i]);
 344                 if (ret)
 345                         /* on error: disable all previously enabled clks */
 346                         fsl_disable_clocks(fsl_edma, i);
 347
 348         }
 349
 350         fsl_edma->big_endian = of_property_read_bool(np, "big-endian");
 351
 352         INIT_LIST_HEAD(&fsl_edma->dma_dev.channels);
 353         for (i = 0; i < fsl_edma->n_chans; i++) {
 354                 struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];
 355
 356                 fsl_chan->edma = fsl_edma;
 357                 fsl_chan->pm_state = RUNNING;
 358                 fsl_chan->slave_id = 0;
 359                 fsl_chan->idle = true;
 360                 fsl_chan->dma_dir = DMA_NONE;
 361                 fsl_chan->vchan.desc_free = fsl_edma_free_desc;
 362                 vchan_init(&fsl_chan->vchan, &fsl_edma->dma_dev);
 363
 364                 edma_writew(fsl_edma, 0x0, &regs->tcd[i].csr);
 365                 fsl_edma_chan_mux(fsl_chan, 0, false);
 366         }
 367
 368         edma_writel(fsl_edma, ~0, regs->intl);
 369         ret = fsl_edma->drvdata->setup_irq(pdev, fsl_edma);
 370         if (ret)
 371                 return ret;
 372
 373         dma_cap_set(DMA_PRIVATE, fsl_edma->dma_dev.cap_mask);
 374         dma_cap_set(DMA_SLAVE, fsl_edma->dma_dev.cap_mask);
 375         dma_cap_set(DMA_CYCLIC, fsl_edma->dma_dev.cap_mask);
 376         dma_cap_set(DMA_MEMCPY, fsl_edma->dma_dev.cap_mask);
 377
 378         fsl_edma->dma_dev.dev = &pdev->dev;
 379         fsl_edma->dma_dev.device_alloc_chan_resources
 380                 = fsl_edma_alloc_chan_resources;
 381         fsl_edma->dma_dev.device_free_chan_resources
 382                 = fsl_edma_free_chan_resources;
 383         fsl_edma->dma_dev.device_tx_status = fsl_edma_tx_status;
 384         fsl_edma->dma_dev.device_prep_slave_sg = fsl_edma_prep_slave_sg;
 385         fsl_edma->dma_dev.device_prep_dma_cyclic = fsl_edma_prep_dma_cyclic;
 386         fsl_edma->dma_dev.device_prep_dma_memcpy = fsl_edma_prep_memcpy;
 387         fsl_edma->dma_dev.device_config = fsl_edma_slave_config;
 388         fsl_edma->dma_dev.device_pause = fsl_edma_pause;
 389         fsl_edma->dma_dev.device_resume = fsl_edma_resume;
 390         fsl_edma->dma_dev.device_terminate_all = fsl_edma_terminate_all;
 391         fsl_edma->dma_dev.device_synchronize = fsl_edma_synchronize;
 392         fsl_edma->dma_dev.device_issue_pending = fsl_edma_issue_pending;
 393
 394         fsl_edma->dma_dev.src_addr_widths = FSL_EDMA_BUSWIDTHS;
 395         fsl_edma->dma_dev.dst_addr_widths = FSL_EDMA_BUSWIDTHS;
 396         fsl_edma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
 397
 398         fsl_edma->dma_dev.copy_align = DMAENGINE_ALIGN_32_BYTES;
 399         /* Per worst case 'nbytes = 1' take CITER as the max_seg_size */
 400         dma_set_max_seg_size(fsl_edma->dma_dev.dev, 0x3fff);
 401
 402         platform_set_drvdata(pdev, fsl_edma);
 403
 404         ret = dma_async_device_register(&fsl_edma->dma_dev);
 405         if (ret) {
 406                 dev_err(&pdev->dev,
 407                         "Can't register Freescale eDMA engine. (%d)\n", ret);
 408                 fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs);
 409                 return ret;
 410         }
 411
 412         ret = of_dma_controller_register(np, fsl_edma_xlate, fsl_edma);
 413         if (ret) {
 414                 dev_err(&pdev->dev,
 415                         "Can't register Freescale eDMA of_dma. (%d)\n", ret);
 416                 dma_async_device_unregister(&fsl_edma->dma_dev);
 417                 fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs);
 418                 return ret;
 419         }
 420
 421         /* enable round robin arbitration */
 422         edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
 423
 424         return 0;
 425 }
 426
 427 static int fsl_edma_remove(struct platform_device *pdev)
 428 {
 429         struct device_node *np = pdev->dev.of_node;
 430         struct fsl_edma_engine *fsl_edma = platform_get_drvdata(pdev);
 431
 432         fsl_edma_irq_exit(pdev, fsl_edma);
 433         fsl_edma_cleanup_vchan(&fsl_edma->dma_dev);
 434         of_dma_controller_free(np);
 435         dma_async_device_unregister(&fsl_edma->dma_dev);
 436         fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs);
 437
 438         return 0;
 439 }
 440
 441 static int fsl_edma_suspend_late(struct device *dev)
 442 {
 443         struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
 444         struct fsl_edma_chan *fsl_chan;
 445         unsigned long flags;
 446         int i;
 447
 448         for (i = 0; i < fsl_edma->n_chans; i++) {
 449                 fsl_chan = &fsl_edma->chans[i];
 450                 spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
 451                 /* Make sure chan is idle or will force disable. */
 452                 if (unlikely(!fsl_chan->idle)) {
 453                         dev_warn(dev, "WARN: There is non-idle channel.");
 454                         fsl_edma_disable_request(fsl_chan);
 455                         fsl_edma_chan_mux(fsl_chan, 0, false);
 456                 }
 457
 458                 fsl_chan->pm_state = SUSPENDED;
 459                 spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
 460         }
 461
 462         return 0;
 463 }
 464
 465 static int fsl_edma_resume_early(struct device *dev)
 466 {
 467         struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
 468         struct fsl_edma_chan *fsl_chan;
 469         struct edma_regs *regs = &fsl_edma->regs;
 470         int i;
 471
 472         for (i = 0; i < fsl_edma->n_chans; i++) {
 473                 fsl_chan = &fsl_edma->chans[i];
 474                 fsl_chan->pm_state = RUNNING;
 475                 edma_writew(fsl_edma, 0x0, &regs->tcd[i].csr);
 476                 if (fsl_chan->slave_id != 0)
 477                         fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id, true);
 478         }
 479
 480         edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
 481
 482         return 0;
 483 }
 484
 485 /*
 486  * eDMA provides the service to others, so it should be suspend late
 487  * and resume early. When eDMA suspend, all of the clients should stop
 488  * the DMA data transmission and let the channel idle.
 489  */
 490 static const struct dev_pm_ops fsl_edma_pm_ops = {
 491         .suspend_late   = fsl_edma_suspend_late,
 492         .resume_early   = fsl_edma_resume_early,
 493 };
 494
 495 static struct platform_driver fsl_edma_driver = {
 496         .driver         = {
 497                 .name   = "fsl-edma",
 498                 .of_match_table = fsl_edma_dt_ids,
 499                 .pm     = &fsl_edma_pm_ops,
 500         },
 501         .probe          = fsl_edma_probe,
 502         .remove         = fsl_edma_remove,
 503 };
 504
 505 static int __init fsl_edma_init(void)
 506 {
 507         return platform_driver_register(&fsl_edma_driver);
 508 }
 509 subsys_initcall(fsl_edma_init);
 510
 511 static void __exit fsl_edma_exit(void)
 512 {
 513         platform_driver_unregister(&fsl_edma_driver);
 514 }
 515 module_exit(fsl_edma_exit);
 516
 517 MODULE_ALIAS("platform:fsl-edma");
 518 MODULE_DESCRIPTION("Freescale eDMA engine driver");
 519 MODULE_LICENSE("GPL v2");