drivers/rapidio/devices/tsi721_dma.c

   1 /*
   2  * DMA Engine support for Tsi721 PCIExpress-to-SRIO bridge
   3  *
   4  * Copyright 2011 Integrated Device Technology, Inc.
   5  * Alexandre Bounine <alexandre.bounine@idt.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the Free
   9  * Software Foundation; either version 2 of the License, or (at your option)
  10  * any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful, but WITHOUT
  13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  15  * more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along with
  18  * this program; if not, write to the Free Software Foundation, Inc., 59
  19  * Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  20  */
  21
  22 #include <linux/io.h>
  23 #include <linux/errno.h>
  24 #include <linux/init.h>
  25 #include <linux/ioport.h>
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28 #include <linux/pci.h>
  29 #include <linux/rio.h>
  30 #include <linux/rio_drv.h>
  31 #include <linux/dma-mapping.h>
  32 #include <linux/interrupt.h>
  33 #include <linux/kfifo.h>
  34 #include <linux/delay.h>
  35
  36 #include "tsi721.h"
  37
  38 static inline struct tsi721_bdma_chan *to_tsi721_chan(struct dma_chan *chan)
  39 {
  40         return container_of(chan, struct tsi721_bdma_chan, dchan);
  41 }
  42
  43 static inline struct tsi721_device *to_tsi721(struct dma_device *ddev)
  44 {
  45         return container_of(ddev, struct rio_mport, dma)->priv;
  46 }
  47
  48 static inline
  49 struct tsi721_tx_desc *to_tsi721_desc(struct dma_async_tx_descriptor *txd)
  50 {
  51         return container_of(txd, struct tsi721_tx_desc, txd);
  52 }
  53
  54 static inline
  55 struct tsi721_tx_desc *tsi721_dma_first_active(
  56                                 struct tsi721_bdma_chan *bdma_chan)
  57 {
  58         return list_first_entry(&bdma_chan->active_list,
  59                                 struct tsi721_tx_desc, desc_node);
  60 }
  61
  62 static int tsi721_bdma_ch_init(struct tsi721_bdma_chan *bdma_chan)
  63 {
  64         struct tsi721_dma_desc *bd_ptr;
  65         struct device *dev = bdma_chan->dchan.device->dev;
  66         u64             *sts_ptr;
  67         dma_addr_t      bd_phys;
  68         dma_addr_t      sts_phys;
  69         int             sts_size;
  70         int             bd_num = bdma_chan->bd_num;
  71
  72         dev_dbg(dev, "Init Block DMA Engine, CH%d\n", bdma_chan->id);
  73
  74         /* Allocate space for DMA descriptors */
  75         bd_ptr = dma_zalloc_coherent(dev,
  76                                 bd_num * sizeof(struct tsi721_dma_desc),
  77                                 &bd_phys, GFP_KERNEL);
  78         if (!bd_ptr)
  79                 return -ENOMEM;
  80
  81         bdma_chan->bd_phys = bd_phys;
  82         bdma_chan->bd_base = bd_ptr;
  83
  84         dev_dbg(dev, "DMA descriptors @ %p (phys = %llx)\n",
  85                 bd_ptr, (unsigned long long)bd_phys);
  86
  87         /* Allocate space for descriptor status FIFO */
  88         sts_size = (bd_num >= TSI721_DMA_MINSTSSZ) ?
  89                                         bd_num : TSI721_DMA_MINSTSSZ;
  90         sts_size = roundup_pow_of_two(sts_size);
  91         sts_ptr = dma_zalloc_coherent(dev,
  92                                      sts_size * sizeof(struct tsi721_dma_sts),
  93                                      &sts_phys, GFP_KERNEL);
  94         if (!sts_ptr) {
  95                 /* Free space allocated for DMA descriptors */
  96                 dma_free_coherent(dev,
  97                                   bd_num * sizeof(struct tsi721_dma_desc),
  98                                   bd_ptr, bd_phys);
  99                 bdma_chan->bd_base = NULL;
 100                 return -ENOMEM;
 101         }
 102
 103         bdma_chan->sts_phys = sts_phys;
 104         bdma_chan->sts_base = sts_ptr;
 105         bdma_chan->sts_size = sts_size;
 106
 107         dev_dbg(dev,
 108                 "desc status FIFO @ %p (phys = %llx) size=0x%x\n",
 109                 sts_ptr, (unsigned long long)sts_phys, sts_size);
 110
 111         /* Initialize DMA descriptors ring */
 112         bd_ptr[bd_num - 1].type_id = cpu_to_le32(DTYPE3 << 29);
 113         bd_ptr[bd_num - 1].next_lo = cpu_to_le32((u64)bd_phys &
 114                                                  TSI721_DMAC_DPTRL_MASK);
 115         bd_ptr[bd_num - 1].next_hi = cpu_to_le32((u64)bd_phys >> 32);
 116
 117         /* Setup DMA descriptor pointers */
 118         iowrite32(((u64)bd_phys >> 32),
 119                 bdma_chan->regs + TSI721_DMAC_DPTRH);
 120         iowrite32(((u64)bd_phys & TSI721_DMAC_DPTRL_MASK),
 121                 bdma_chan->regs + TSI721_DMAC_DPTRL);
 122
 123         /* Setup descriptor status FIFO */
 124         iowrite32(((u64)sts_phys >> 32),
 125                 bdma_chan->regs + TSI721_DMAC_DSBH);
 126         iowrite32(((u64)sts_phys & TSI721_DMAC_DSBL_MASK),
 127                 bdma_chan->regs + TSI721_DMAC_DSBL);
 128         iowrite32(TSI721_DMAC_DSSZ_SIZE(sts_size),
 129                 bdma_chan->regs + TSI721_DMAC_DSSZ);
 130
 131         /* Clear interrupt bits */
 132         iowrite32(TSI721_DMAC_INT_ALL,
 133                 bdma_chan->regs + TSI721_DMAC_INT);
 134
 135         ioread32(bdma_chan->regs + TSI721_DMAC_INT);
 136
 137         /* Toggle DMA channel initialization */
 138         iowrite32(TSI721_DMAC_CTL_INIT, bdma_chan->regs + TSI721_DMAC_CTL);
 139         ioread32(bdma_chan->regs + TSI721_DMAC_CTL);
 140         bdma_chan->wr_count = bdma_chan->wr_count_next = 0;
 141         bdma_chan->sts_rdptr = 0;
 142         udelay(10);
 143
 144         return 0;
 145 }
 146
 147 static int tsi721_bdma_ch_free(struct tsi721_bdma_chan *bdma_chan)
 148 {
 149         u32 ch_stat;
 150
 151         if (bdma_chan->bd_base == NULL)
 152                 return 0;
 153
 154         /* Check if DMA channel still running */
 155         ch_stat = ioread32(bdma_chan->regs + TSI721_DMAC_STS);
 156         if (ch_stat & TSI721_DMAC_STS_RUN)
 157                 return -EFAULT;
 158
 159         /* Put DMA channel into init state */
 160         iowrite32(TSI721_DMAC_CTL_INIT, bdma_chan->regs + TSI721_DMAC_CTL);
 161
 162         /* Free space allocated for DMA descriptors */
 163         dma_free_coherent(bdma_chan->dchan.device->dev,
 164                 bdma_chan->bd_num * sizeof(struct tsi721_dma_desc),
 165                 bdma_chan->bd_base, bdma_chan->bd_phys);
 166         bdma_chan->bd_base = NULL;
 167
 168         /* Free space allocated for status FIFO */
 169         dma_free_coherent(bdma_chan->dchan.device->dev,
 170                 bdma_chan->sts_size * sizeof(struct tsi721_dma_sts),
 171                 bdma_chan->sts_base, bdma_chan->sts_phys);
 172         bdma_chan->sts_base = NULL;
 173         return 0;
 174 }
 175
 176 static void
 177 tsi721_bdma_interrupt_enable(struct tsi721_bdma_chan *bdma_chan, int enable)
 178 {
 179         if (enable) {
 180                 /* Clear pending BDMA channel interrupts */
 181                 iowrite32(TSI721_DMAC_INT_ALL,
 182                         bdma_chan->regs + TSI721_DMAC_INT);
 183                 ioread32(bdma_chan->regs + TSI721_DMAC_INT);
 184                 /* Enable BDMA channel interrupts */
 185                 iowrite32(TSI721_DMAC_INT_ALL,
 186                         bdma_chan->regs + TSI721_DMAC_INTE);
 187         } else {
 188                 /* Disable BDMA channel interrupts */
 189                 iowrite32(0, bdma_chan->regs + TSI721_DMAC_INTE);
 190                 /* Clear pending BDMA channel interrupts */
 191                 iowrite32(TSI721_DMAC_INT_ALL,
 192                         bdma_chan->regs + TSI721_DMAC_INT);
 193         }
 194
 195 }
 196
 197 static bool tsi721_dma_is_idle(struct tsi721_bdma_chan *bdma_chan)
 198 {
 199         u32 sts;
 200
 201         sts = ioread32(bdma_chan->regs + TSI721_DMAC_STS);
 202         return ((sts & TSI721_DMAC_STS_RUN) == 0);
 203 }
 204
 205 void tsi721_bdma_handler(struct tsi721_bdma_chan *bdma_chan)
 206 {
 207         /* Disable BDMA channel interrupts */
 208         iowrite32(0, bdma_chan->regs + TSI721_DMAC_INTE);
 209         if (bdma_chan->active)
 210                 tasklet_schedule(&bdma_chan->tasklet);
 211 }
 212
 213 #ifdef CONFIG_PCI_MSI
 214 /**
 215  * tsi721_omsg_msix - MSI-X interrupt handler for BDMA channels
 216  * @irq: Linux interrupt number
 217  * @ptr: Pointer to interrupt-specific data (BDMA channel structure)
 218  *
 219  * Handles BDMA channel interrupts signaled using MSI-X.
 220  */
 221 static irqreturn_t tsi721_bdma_msix(int irq, void *ptr)
 222 {
 223         struct tsi721_bdma_chan *bdma_chan = ptr;
 224
 225         tsi721_bdma_handler(bdma_chan);
 226         return IRQ_HANDLED;
 227 }
 228 #endif /* CONFIG_PCI_MSI */
 229
 230 /* Must be called with the spinlock held */
 231 static void tsi721_start_dma(struct tsi721_bdma_chan *bdma_chan)
 232 {
 233         if (!tsi721_dma_is_idle(bdma_chan)) {
 234                 dev_err(bdma_chan->dchan.device->dev,
 235                         "BUG: Attempt to start non-idle channel\n");
 236                 return;
 237         }
 238
 239         if (bdma_chan->wr_count == bdma_chan->wr_count_next) {
 240                 dev_err(bdma_chan->dchan.device->dev,
 241                         "BUG: Attempt to start DMA with no BDs ready\n");
 242                 return;
 243         }
 244
 245         dev_dbg(bdma_chan->dchan.device->dev,
 246                 "tx_chan: %p, chan: %d, regs: %p\n",
 247                 bdma_chan, bdma_chan->dchan.chan_id, bdma_chan->regs);
 248
 249         iowrite32(bdma_chan->wr_count_next,
 250                 bdma_chan->regs + TSI721_DMAC_DWRCNT);
 251         ioread32(bdma_chan->regs + TSI721_DMAC_DWRCNT);
 252
 253         bdma_chan->wr_count = bdma_chan->wr_count_next;
 254 }
 255
 256 static void tsi721_desc_put(struct tsi721_bdma_chan *bdma_chan,
 257                             struct tsi721_tx_desc *desc)
 258 {
 259         dev_dbg(bdma_chan->dchan.device->dev,
 260                 "Put desc: %p into free list\n", desc);
 261
 262         if (desc) {
 263                 spin_lock_bh(&bdma_chan->lock);
 264                 list_splice_init(&desc->tx_list, &bdma_chan->free_list);
 265                 list_add(&desc->desc_node, &bdma_chan->free_list);
 266                 bdma_chan->wr_count_next = bdma_chan->wr_count;
 267                 spin_unlock_bh(&bdma_chan->lock);
 268         }
 269 }
 270
 271 static
 272 struct tsi721_tx_desc *tsi721_desc_get(struct tsi721_bdma_chan *bdma_chan)
 273 {
 274         struct tsi721_tx_desc *tx_desc, *_tx_desc;
 275         struct tsi721_tx_desc *ret = NULL;
 276         int i;
 277
 278         spin_lock_bh(&bdma_chan->lock);
 279         list_for_each_entry_safe(tx_desc, _tx_desc,
 280                                  &bdma_chan->free_list, desc_node) {
 281                 if (async_tx_test_ack(&tx_desc->txd)) {
 282                         list_del(&tx_desc->desc_node);
 283                         ret = tx_desc;
 284                         break;
 285                 }
 286                 dev_dbg(bdma_chan->dchan.device->dev,
 287                         "desc %p not ACKed\n", tx_desc);
 288         }
 289
 290         i = bdma_chan->wr_count_next % bdma_chan->bd_num;
 291         if (i == bdma_chan->bd_num - 1) {
 292                 i = 0;
 293                 bdma_chan->wr_count_next++; /* skip link descriptor */
 294         }
 295
 296         bdma_chan->wr_count_next++;
 297         tx_desc->txd.phys = bdma_chan->bd_phys +
 298                                 i * sizeof(struct tsi721_dma_desc);
 299         tx_desc->hw_desc = &((struct tsi721_dma_desc *)bdma_chan->bd_base)[i];
 300
 301         spin_unlock_bh(&bdma_chan->lock);
 302
 303         return ret;
 304 }
 305
 306 static int
 307 tsi721_desc_fill_init(struct tsi721_tx_desc *desc, struct scatterlist *sg,
 308         enum dma_rtype rtype, u32 sys_size)
 309 {
 310         struct tsi721_dma_desc *bd_ptr = desc->hw_desc;
 311         u64 rio_addr;
 312
 313         /* Initialize DMA descriptor */
 314         bd_ptr->type_id = cpu_to_le32((DTYPE1 << 29) |
 315                                         (rtype << 19) | desc->destid);
 316         bd_ptr->bcount = cpu_to_le32(((desc->rio_addr & 0x3) << 30) |
 317                                      (sys_size << 26));
 318         rio_addr = (desc->rio_addr >> 2) |
 319                                 ((u64)(desc->rio_addr_u & 0x3) << 62);
 320         bd_ptr->raddr_lo = cpu_to_le32(rio_addr & 0xffffffff);
 321         bd_ptr->raddr_hi = cpu_to_le32(rio_addr >> 32);
 322         bd_ptr->t1.bufptr_lo = cpu_to_le32(
 323                                         (u64)sg_dma_address(sg) & 0xffffffff);
 324         bd_ptr->t1.bufptr_hi = cpu_to_le32((u64)sg_dma_address(sg) >> 32);
 325         bd_ptr->t1.s_dist = 0;
 326         bd_ptr->t1.s_size = 0;
 327
 328         return 0;
 329 }
 330
 331 static int
 332 tsi721_desc_fill_end(struct tsi721_tx_desc *desc)
 333 {
 334         struct tsi721_dma_desc *bd_ptr = desc->hw_desc;
 335
 336         /* Update DMA descriptor */
 337         if (desc->interrupt)
 338                 bd_ptr->type_id |= cpu_to_le32(TSI721_DMAD_IOF);
 339         bd_ptr->bcount |= cpu_to_le32(desc->bcount & TSI721_DMAD_BCOUNT1);
 340
 341         return 0;
 342 }
 343
 344
 345 static void tsi721_dma_chain_complete(struct tsi721_bdma_chan *bdma_chan,
 346                                       struct tsi721_tx_desc *desc)
 347 {
 348         struct dma_async_tx_descriptor *txd = &desc->txd;
 349         dma_async_tx_callback callback = txd->callback;
 350         void *param = txd->callback_param;
 351
 352         list_splice_init(&desc->tx_list, &bdma_chan->free_list);
 353         list_move(&desc->desc_node, &bdma_chan->free_list);
 354         bdma_chan->completed_cookie = txd->cookie;
 355
 356         if (callback)
 357                 callback(param);
 358 }
 359
 360 static void tsi721_dma_complete_all(struct tsi721_bdma_chan *bdma_chan)
 361 {
 362         struct tsi721_tx_desc *desc, *_d;
 363         LIST_HEAD(list);
 364
 365         BUG_ON(!tsi721_dma_is_idle(bdma_chan));
 366
 367         if (!list_empty(&bdma_chan->queue))
 368                 tsi721_start_dma(bdma_chan);
 369
 370         list_splice_init(&bdma_chan->active_list, &list);
 371         list_splice_init(&bdma_chan->queue, &bdma_chan->active_list);
 372
 373         list_for_each_entry_safe(desc, _d, &list, desc_node)
 374                 tsi721_dma_chain_complete(bdma_chan, desc);
 375 }
 376
 377 static void tsi721_clr_stat(struct tsi721_bdma_chan *bdma_chan)
 378 {
 379         u32 srd_ptr;
 380         u64 *sts_ptr;
 381         int i, j;
 382
 383         /* Check and clear descriptor status FIFO entries */
 384         srd_ptr = bdma_chan->sts_rdptr;
 385         sts_ptr = bdma_chan->sts_base;
 386         j = srd_ptr * 8;
 387         while (sts_ptr[j]) {
 388                 for (i = 0; i < 8 && sts_ptr[j]; i++, j++)
 389                         sts_ptr[j] = 0;
 390
 391                 ++srd_ptr;
 392                 srd_ptr %= bdma_chan->sts_size;
 393                 j = srd_ptr * 8;
 394         }
 395
 396         iowrite32(srd_ptr, bdma_chan->regs + TSI721_DMAC_DSRP);
 397         bdma_chan->sts_rdptr = srd_ptr;
 398 }
 399
 400 static void tsi721_advance_work(struct tsi721_bdma_chan *bdma_chan)
 401 {
 402         if (list_empty(&bdma_chan->active_list) ||
 403                 list_is_singular(&bdma_chan->active_list)) {
 404                 dev_dbg(bdma_chan->dchan.device->dev,
 405                         "%s: Active_list empty\n", __func__);
 406                 tsi721_dma_complete_all(bdma_chan);
 407         } else {
 408                 dev_dbg(bdma_chan->dchan.device->dev,
 409                         "%s: Active_list NOT empty\n", __func__);
 410                 tsi721_dma_chain_complete(bdma_chan,
 411                                         tsi721_dma_first_active(bdma_chan));
 412                 tsi721_start_dma(bdma_chan);
 413         }
 414 }
 415
 416 static void tsi721_dma_tasklet(unsigned long data)
 417 {
 418         struct tsi721_bdma_chan *bdma_chan = (struct tsi721_bdma_chan *)data;
 419         u32 dmac_int, dmac_sts;
 420
 421         dmac_int = ioread32(bdma_chan->regs + TSI721_DMAC_INT);
 422         dev_dbg(bdma_chan->dchan.device->dev, "%s: DMAC%d_INT = 0x%x\n",
 423                 __func__, bdma_chan->id, dmac_int);
 424         /* Clear channel interrupts */
 425         iowrite32(dmac_int, bdma_chan->regs + TSI721_DMAC_INT);
 426
 427         if (dmac_int & TSI721_DMAC_INT_ERR) {
 428                 dmac_sts = ioread32(bdma_chan->regs + TSI721_DMAC_STS);
 429                 dev_err(bdma_chan->dchan.device->dev,
 430                         "%s: DMA ERROR - DMAC%d_STS = 0x%x\n",
 431                         __func__, bdma_chan->id, dmac_sts);
 432         }
 433
 434         if (dmac_int & TSI721_DMAC_INT_STFULL) {
 435                 dev_err(bdma_chan->dchan.device->dev,
 436                         "%s: DMAC%d descriptor status FIFO is full\n",
 437                         __func__, bdma_chan->id);
 438         }
 439
 440         if (dmac_int & (TSI721_DMAC_INT_DONE | TSI721_DMAC_INT_IOFDONE)) {
 441                 tsi721_clr_stat(bdma_chan);
 442                 spin_lock(&bdma_chan->lock);
 443                 tsi721_advance_work(bdma_chan);
 444                 spin_unlock(&bdma_chan->lock);
 445         }
 446
 447         /* Re-Enable BDMA channel interrupts */
 448         iowrite32(TSI721_DMAC_INT_ALL, bdma_chan->regs + TSI721_DMAC_INTE);
 449 }
 450
 451 static dma_cookie_t tsi721_tx_submit(struct dma_async_tx_descriptor *txd)
 452 {
 453         struct tsi721_tx_desc *desc = to_tsi721_desc(txd);
 454         struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(txd->chan);
 455         dma_cookie_t cookie;
 456
 457         spin_lock_bh(&bdma_chan->lock);
 458
 459         cookie = txd->chan->cookie;
 460         if (++cookie < 0)
 461                 cookie = 1;
 462         txd->chan->cookie = cookie;
 463         txd->cookie = cookie;
 464
 465         if (list_empty(&bdma_chan->active_list)) {
 466                 list_add_tail(&desc->desc_node, &bdma_chan->active_list);
 467                 tsi721_start_dma(bdma_chan);
 468         } else {
 469                 list_add_tail(&desc->desc_node, &bdma_chan->queue);
 470         }
 471
 472         spin_unlock_bh(&bdma_chan->lock);
 473         return cookie;
 474 }
 475
 476 static int tsi721_alloc_chan_resources(struct dma_chan *dchan)
 477 {
 478         struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
 479 #ifdef CONFIG_PCI_MSI
 480         struct tsi721_device *priv = to_tsi721(dchan->device);
 481 #endif
 482         struct tsi721_tx_desc *desc = NULL;
 483         LIST_HEAD(tmp_list);
 484         int i;
 485         int rc;
 486
 487         if (bdma_chan->bd_base)
 488                 return bdma_chan->bd_num - 1;
 489
 490         /* Initialize BDMA channel */
 491         if (tsi721_bdma_ch_init(bdma_chan)) {
 492                 dev_err(dchan->device->dev, "Unable to initialize data DMA"
 493                         " channel %d, aborting\n", bdma_chan->id);
 494                 return -ENOMEM;
 495         }
 496
 497         /* Alocate matching number of logical descriptors */
 498         desc = kcalloc((bdma_chan->bd_num - 1), sizeof(struct tsi721_tx_desc),
 499                         GFP_KERNEL);
 500         if (!desc) {
 501                 dev_err(dchan->device->dev,
 502                         "Failed to allocate logical descriptors\n");
 503                 rc = -ENOMEM;
 504                 goto err_out;
 505         }
 506
 507         bdma_chan->tx_desc = desc;
 508
 509         for (i = 0; i < bdma_chan->bd_num - 1; i++) {
 510                 dma_async_tx_descriptor_init(&desc[i].txd, dchan);
 511                 desc[i].txd.tx_submit = tsi721_tx_submit;
 512                 desc[i].txd.flags = DMA_CTRL_ACK;
 513                 INIT_LIST_HEAD(&desc[i].tx_list);
 514                 list_add_tail(&desc[i].desc_node, &tmp_list);
 515         }
 516
 517         spin_lock_bh(&bdma_chan->lock);
 518         list_splice(&tmp_list, &bdma_chan->free_list);
 519         bdma_chan->completed_cookie = dchan->cookie = 1;
 520         spin_unlock_bh(&bdma_chan->lock);
 521
 522 #ifdef CONFIG_PCI_MSI
 523         if (priv->flags & TSI721_USING_MSIX) {
 524                 /* Request interrupt service if we are in MSI-X mode */
 525                 rc = request_irq(
 526                         priv->msix[TSI721_VECT_DMA0_DONE +
 527                                    bdma_chan->id].vector,
 528                         tsi721_bdma_msix, 0,
 529                         priv->msix[TSI721_VECT_DMA0_DONE +
 530                                    bdma_chan->id].irq_name,
 531                         (void *)bdma_chan);
 532
 533                 if (rc) {
 534                         dev_dbg(dchan->device->dev,
 535                                 "Unable to allocate MSI-X interrupt for "
 536                                 "BDMA%d-DONE\n", bdma_chan->id);
 537                         goto err_out;
 538                 }
 539
 540                 rc = request_irq(priv->msix[TSI721_VECT_DMA0_INT +
 541                                             bdma_chan->id].vector,
 542                                 tsi721_bdma_msix, 0,
 543                                 priv->msix[TSI721_VECT_DMA0_INT +
 544                                            bdma_chan->id].irq_name,
 545                                 (void *)bdma_chan);
 546
 547                 if (rc) {
 548                         dev_dbg(dchan->device->dev,
 549                                 "Unable to allocate MSI-X interrupt for "
 550                                 "BDMA%d-INT\n", bdma_chan->id);
 551                         free_irq(
 552                                 priv->msix[TSI721_VECT_DMA0_DONE +
 553                                            bdma_chan->id].vector,
 554                                 (void *)bdma_chan);
 555                         rc = -EIO;
 556                         goto err_out;
 557                 }
 558         }
 559 #endif /* CONFIG_PCI_MSI */
 560
 561         bdma_chan->active = true;
 562         tsi721_bdma_interrupt_enable(bdma_chan, 1);
 563
 564         return bdma_chan->bd_num - 1;
 565
 566 err_out:
 567         kfree(desc);
 568         tsi721_bdma_ch_free(bdma_chan);
 569         return rc;
 570 }
 571
 572 static void tsi721_free_chan_resources(struct dma_chan *dchan)
 573 {
 574         struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
 575         struct tsi721_device *priv = to_tsi721(dchan->device);
 576         LIST_HEAD(list);
 577
 578         dev_dbg(dchan->device->dev, "%s: Entry\n", __func__);
 579
 580         if (bdma_chan->bd_base == NULL)
 581                 return;
 582
 583         BUG_ON(!list_empty(&bdma_chan->active_list));
 584         BUG_ON(!list_empty(&bdma_chan->queue));
 585
 586         tsi721_bdma_interrupt_enable(bdma_chan, 0);
 587         bdma_chan->active = false;
 588
 589 #ifdef CONFIG_PCI_MSI
 590         if (priv->flags & TSI721_USING_MSIX) {
 591                 synchronize_irq(priv->msix[TSI721_VECT_DMA0_DONE +
 592                                            bdma_chan->id].vector);
 593                 synchronize_irq(priv->msix[TSI721_VECT_DMA0_INT +
 594                                            bdma_chan->id].vector);
 595         } else
 596 #endif
 597         synchronize_irq(priv->pdev->irq);
 598
 599         tasklet_kill(&bdma_chan->tasklet);
 600
 601         spin_lock_bh(&bdma_chan->lock);
 602         list_splice_init(&bdma_chan->free_list, &list);
 603         spin_unlock_bh(&bdma_chan->lock);
 604
 605 #ifdef CONFIG_PCI_MSI
 606         if (priv->flags & TSI721_USING_MSIX) {
 607                 free_irq(priv->msix[TSI721_VECT_DMA0_DONE +
 608                                     bdma_chan->id].vector, (void *)bdma_chan);
 609                 free_irq(priv->msix[TSI721_VECT_DMA0_INT +
 610                                     bdma_chan->id].vector, (void *)bdma_chan);
 611         }
 612 #endif /* CONFIG_PCI_MSI */
 613
 614         tsi721_bdma_ch_free(bdma_chan);
 615         kfree(bdma_chan->tx_desc);
 616 }
 617
 618 static
 619 enum dma_status tsi721_tx_status(struct dma_chan *dchan, dma_cookie_t cookie,
 620                                  struct dma_tx_state *txstate)
 621 {
 622         struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
 623         dma_cookie_t            last_used;
 624         dma_cookie_t            last_completed;
 625         int                     ret;
 626
 627         spin_lock_bh(&bdma_chan->lock);
 628         last_completed = bdma_chan->completed_cookie;
 629         last_used = dchan->cookie;
 630         spin_unlock_bh(&bdma_chan->lock);
 631
 632         ret = dma_async_is_complete(cookie, last_completed, last_used);
 633
 634         dma_set_tx_state(txstate, last_completed, last_used, 0);
 635
 636         dev_dbg(dchan->device->dev,
 637                 "%s: exit, ret: %d, last_completed: %d, last_used: %d\n",
 638                 __func__, ret, last_completed, last_used);
 639
 640         return ret;
 641 }
 642
 643 static void tsi721_issue_pending(struct dma_chan *dchan)
 644 {
 645         struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
 646
 647         dev_dbg(dchan->device->dev, "%s: Entry\n", __func__);
 648
 649         if (tsi721_dma_is_idle(bdma_chan)) {
 650                 spin_lock_bh(&bdma_chan->lock);
 651                 tsi721_advance_work(bdma_chan);
 652                 spin_unlock_bh(&bdma_chan->lock);
 653         } else
 654                 dev_dbg(dchan->device->dev,
 655                         "%s: DMA channel still busy\n", __func__);
 656 }
 657
 658 static
 659 struct dma_async_tx_descriptor *tsi721_prep_rio_sg(struct dma_chan *dchan,
 660                         struct scatterlist *sgl, unsigned int sg_len,
 661                         enum dma_transfer_direction dir, unsigned long flags,
 662                         void *tinfo)
 663 {
 664         struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
 665         struct tsi721_tx_desc *desc = NULL;
 666         struct tsi721_tx_desc *first = NULL;
 667         struct scatterlist *sg;
 668         struct rio_dma_ext *rext = tinfo;
 669         u64 rio_addr = rext->rio_addr; /* limited to 64-bit rio_addr for now */
 670         unsigned int i;
 671         u32 sys_size = dma_to_mport(dchan->device)->sys_size;
 672         enum dma_rtype rtype;
 673         dma_addr_t next_addr = -1;
 674
 675         if (!sgl || !sg_len) {
 676                 dev_err(dchan->device->dev, "%s: No SG list\n", __func__);
 677                 return NULL;
 678         }
 679
 680         if (dir == DMA_DEV_TO_MEM)
 681                 rtype = NREAD;
 682         else if (dir == DMA_MEM_TO_DEV) {
 683                 switch (rext->wr_type) {
 684                 case RDW_ALL_NWRITE:
 685                         rtype = ALL_NWRITE;
 686                         break;
 687                 case RDW_ALL_NWRITE_R:
 688                         rtype = ALL_NWRITE_R;
 689                         break;
 690                 case RDW_LAST_NWRITE_R:
 691                 default:
 692                         rtype = LAST_NWRITE_R;
 693                         break;
 694                 }
 695         } else {
 696                 dev_err(dchan->device->dev,
 697                         "%s: Unsupported DMA direction option\n", __func__);
 698                 return NULL;
 699         }
 700
 701         for_each_sg(sgl, sg, sg_len, i) {
 702                 int err;
 703
 704                 if (sg_dma_len(sg) > TSI721_BDMA_MAX_BCOUNT) {
 705                         dev_err(dchan->device->dev,
 706                                 "%s: SG entry %d is too large\n", __func__, i);
 707                         goto err_desc_put;
 708                 }
 709
 710                 /*
 711                  * If this sg entry forms contiguous block with previous one,
 712                  * try to merge it into existing DMA descriptor
 713                  */
 714                 if (desc) {
 715                         if (next_addr == sg_dma_address(sg) &&
 716                             desc->bcount + sg_dma_len(sg) <=
 717                                                 TSI721_BDMA_MAX_BCOUNT) {
 718                                 /* Adjust byte count of the descriptor */
 719                                 desc->bcount += sg_dma_len(sg);
 720                                 goto entry_done;
 721                         }
 722
 723                         /*
 724                          * Finalize this descriptor using total
 725                          * byte count value.
 726                          */
 727                         tsi721_desc_fill_end(desc);
 728                         dev_dbg(dchan->device->dev, "%s: desc final len: %d\n",
 729                                 __func__, desc->bcount);
 730                 }
 731
 732                 /*
 733                  * Obtain and initialize a new descriptor
 734                  */
 735                 desc = tsi721_desc_get(bdma_chan);
 736                 if (!desc) {
 737                         dev_err(dchan->device->dev,
 738                                 "%s: Failed to get new descriptor for SG %d\n",
 739                                 __func__, i);
 740                         goto err_desc_put;
 741                 }
 742
 743                 desc->destid = rext->destid;
 744                 desc->rio_addr = rio_addr;
 745                 desc->rio_addr_u = 0;
 746                 desc->bcount = sg_dma_len(sg);
 747
 748                 dev_dbg(dchan->device->dev,
 749                         "sg%d desc: 0x%llx, addr: 0x%llx len: %d\n",
 750                         i, (u64)desc->txd.phys,
 751                         (unsigned long long)sg_dma_address(sg),
 752                         sg_dma_len(sg));
 753
 754                 dev_dbg(dchan->device->dev,
 755                         "bd_ptr = %p did=%d raddr=0x%llx\n",
 756                         desc->hw_desc, desc->destid, desc->rio_addr);
 757
 758                 err = tsi721_desc_fill_init(desc, sg, rtype, sys_size);
 759                 if (err) {
 760                         dev_err(dchan->device->dev,
 761                                 "Failed to build desc: %d\n", err);
 762                         goto err_desc_put;
 763                 }
 764
 765                 next_addr = sg_dma_address(sg);
 766
 767                 if (!first)
 768                         first = desc;
 769                 else
 770                         list_add_tail(&desc->desc_node, &first->tx_list);
 771
 772 entry_done:
 773                 if (sg_is_last(sg)) {
 774                         desc->interrupt = (flags & DMA_PREP_INTERRUPT) != 0;
 775                         tsi721_desc_fill_end(desc);
 776                         dev_dbg(dchan->device->dev, "%s: desc final len: %d\n",
 777                                 __func__, desc->bcount);
 778                 } else {
 779                         rio_addr += sg_dma_len(sg);
 780                         next_addr += sg_dma_len(sg);
 781                 }
 782         }
 783
 784         first->txd.cookie = -EBUSY;
 785         desc->txd.flags = flags;
 786
 787         return &first->txd;
 788
 789 err_desc_put:
 790         tsi721_desc_put(bdma_chan, first);
 791         return NULL;
 792 }
 793
 794 static int tsi721_device_control(struct dma_chan *dchan, enum dma_ctrl_cmd cmd,
 795                              unsigned long arg)
 796 {
 797         struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
 798         struct tsi721_tx_desc *desc, *_d;
 799         LIST_HEAD(list);
 800
 801         dev_dbg(dchan->device->dev, "%s: Entry\n", __func__);
 802
 803         if (cmd != DMA_TERMINATE_ALL)
 804                 return -ENXIO;
 805
 806         spin_lock_bh(&bdma_chan->lock);
 807
 808         /* make sure to stop the transfer */
 809         iowrite32(TSI721_DMAC_CTL_SUSP, bdma_chan->regs + TSI721_DMAC_CTL);
 810
 811         list_splice_init(&bdma_chan->active_list, &list);
 812         list_splice_init(&bdma_chan->queue, &list);
 813
 814         list_for_each_entry_safe(desc, _d, &list, desc_node)
 815                 tsi721_dma_chain_complete(bdma_chan, desc);
 816
 817         spin_unlock_bh(&bdma_chan->lock);
 818
 819         return 0;
 820 }
 821
 822 int tsi721_register_dma(struct tsi721_device *priv)
 823 {
 824         int i;
 825         int nr_channels = TSI721_DMA_MAXCH;
 826         int err;
 827         struct rio_mport *mport = priv->mport;
 828
 829         mport->dma.dev = &priv->pdev->dev;
 830         mport->dma.chancnt = nr_channels;
 831
 832         INIT_LIST_HEAD(&mport->dma.channels);
 833
 834         for (i = 0; i < nr_channels; i++) {
 835                 struct tsi721_bdma_chan *bdma_chan = &priv->bdma[i];
 836
 837                 if (i == TSI721_DMACH_MAINT)
 838                         continue;
 839
 840                 bdma_chan->bd_num = TSI721_BDMA_BD_RING_SZ;
 841                 bdma_chan->regs = priv->regs + TSI721_DMAC_BASE(i);
 842
 843                 bdma_chan->dchan.device = &mport->dma;
 844                 bdma_chan->dchan.cookie = 1;
 845                 bdma_chan->dchan.chan_id = i;
 846                 bdma_chan->id = i;
 847                 bdma_chan->active = false;
 848
 849                 spin_lock_init(&bdma_chan->lock);
 850
 851                 INIT_LIST_HEAD(&bdma_chan->active_list);
 852                 INIT_LIST_HEAD(&bdma_chan->queue);
 853                 INIT_LIST_HEAD(&bdma_chan->free_list);
 854
 855                 tasklet_init(&bdma_chan->tasklet, tsi721_dma_tasklet,
 856                              (unsigned long)bdma_chan);
 857                 list_add_tail(&bdma_chan->dchan.device_node,
 858                               &mport->dma.channels);
 859         }
 860
 861         dma_cap_zero(mport->dma.cap_mask);
 862         dma_cap_set(DMA_PRIVATE, mport->dma.cap_mask);
 863         dma_cap_set(DMA_SLAVE, mport->dma.cap_mask);
 864
 865         mport->dma.device_alloc_chan_resources = tsi721_alloc_chan_resources;
 866         mport->dma.device_free_chan_resources = tsi721_free_chan_resources;
 867         mport->dma.device_tx_status = tsi721_tx_status;
 868         mport->dma.device_issue_pending = tsi721_issue_pending;
 869         mport->dma.device_prep_slave_sg = tsi721_prep_rio_sg;
 870         mport->dma.device_control = tsi721_device_control;
 871
 872         err = dma_async_device_register(&mport->dma);
 873         if (err)
 874                 dev_err(&priv->pdev->dev, "Failed to register DMA device\n");
 875
 876         return err;
 877 }