drivers/dma/xilinx/xdma.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * DMA driver for Xilinx DMA/Bridge Subsystem
   4  *
   5  * Copyright (C) 2017-2020 Xilinx, Inc. All rights reserved.
   6  * Copyright (C) 2022, Advanced Micro Devices, Inc.
   7  */
   8
   9 /*
  10  * The DMA/Bridge Subsystem for PCI Express allows for the movement of data
  11  * between Host memory and the DMA subsystem. It does this by operating on
  12  * 'descriptors' that contain information about the source, destination and
  13  * amount of data to transfer. These direct memory transfers can be both in
  14  * the Host to Card (H2C) and Card to Host (C2H) transfers. The DMA can be
  15  * configured to have a single AXI4 Master interface shared by all channels
  16  * or one AXI4-Stream interface for each channel enabled. Memory transfers are
  17  * specified on a per-channel basis in descriptor linked lists, which the DMA
  18  * fetches from host memory and processes. Events such as descriptor completion
  19  * and errors are signaled using interrupts. The core also provides up to 16
  20  * user interrupt wires that generate interrupts to the host.
  21  */
  22
  23 #include <linux/mod_devicetable.h>
  24 #include <linux/bitfield.h>
  25 #include <linux/dmapool.h>
  26 #include <linux/regmap.h>
  27 #include <linux/dmaengine.h>
  28 #include <linux/dma/amd_xdma.h>
  29 #include <linux/platform_device.h>
  30 #include <linux/platform_data/amd_xdma.h>
  31 #include <linux/dma-mapping.h>
  32 #include <linux/pci.h>
  33 #include "../virt-dma.h"
  34 #include "xdma-regs.h"
  35
  36 /* mmio regmap config for all XDMA registers */
  37 static const struct regmap_config xdma_regmap_config = {
  38         .reg_bits = 32,
  39         .val_bits = 32,
  40         .reg_stride = 4,
  41         .max_register = XDMA_REG_SPACE_LEN,
  42 };
  43
  44 /**
  45  * struct xdma_desc_block - Descriptor block
  46  * @virt_addr: Virtual address of block start
  47  * @dma_addr: DMA address of block start
  48  */
  49 struct xdma_desc_block {
  50         void            *virt_addr;
  51         dma_addr_t      dma_addr;
  52 };
  53
  54 /**
  55  * struct xdma_chan - Driver specific DMA channel structure
  56  * @vchan: Virtual channel
  57  * @xdev_hdl: Pointer to DMA device structure
  58  * @base: Offset of channel registers
  59  * @desc_pool: Descriptor pool
  60  * @busy: Busy flag of the channel
  61  * @dir: Transferring direction of the channel
  62  * @cfg: Transferring config of the channel
  63  * @irq: IRQ assigned to the channel
  64  */
  65 struct xdma_chan {
  66         struct virt_dma_chan            vchan;
  67         void                            *xdev_hdl;
  68         u32                             base;
  69         struct dma_pool                 *desc_pool;
  70         bool                            busy;
  71         enum dma_transfer_direction     dir;
  72         struct dma_slave_config         cfg;
  73         u32                             irq;
  74 };
  75
  76 /**
  77  * struct xdma_desc - DMA desc structure
  78  * @vdesc: Virtual DMA descriptor
  79  * @chan: DMA channel pointer
  80  * @dir: Transferring direction of the request
  81  * @dev_addr: Physical address on DMA device side
  82  * @desc_blocks: Hardware descriptor blocks
  83  * @dblk_num: Number of hardware descriptor blocks
  84  * @desc_num: Number of hardware descriptors
  85  * @completed_desc_num: Completed hardware descriptors
  86  * @cyclic: Cyclic transfer vs. scatter-gather
  87  * @periods: Number of periods in the cyclic transfer
  88  * @period_size: Size of a period in bytes in cyclic transfers
  89  */
  90 struct xdma_desc {
  91         struct virt_dma_desc            vdesc;
  92         struct xdma_chan                *chan;
  93         enum dma_transfer_direction     dir;
  94         u64                             dev_addr;
  95         struct xdma_desc_block          *desc_blocks;
  96         u32                             dblk_num;
  97         u32                             desc_num;
  98         u32                             completed_desc_num;
  99         bool                            cyclic;
 100         u32                             periods;
 101         u32                             period_size;
 102 };
 103
 104 #define XDMA_DEV_STATUS_REG_DMA         BIT(0)
 105 #define XDMA_DEV_STATUS_INIT_MSIX       BIT(1)
 106
 107 /**
 108  * struct xdma_device - DMA device structure
 109  * @pdev: Platform device pointer
 110  * @dma_dev: DMA device structure
 111  * @rmap: MMIO regmap for DMA registers
 112  * @h2c_chans: Host to Card channels
 113  * @c2h_chans: Card to Host channels
 114  * @h2c_chan_num: Number of H2C channels
 115  * @c2h_chan_num: Number of C2H channels
 116  * @irq_start: Start IRQ assigned to device
 117  * @irq_num: Number of IRQ assigned to device
 118  * @status: Initialization status
 119  */
 120 struct xdma_device {
 121         struct platform_device  *pdev;
 122         struct dma_device       dma_dev;
 123         struct regmap           *rmap;
 124         struct xdma_chan        *h2c_chans;
 125         struct xdma_chan        *c2h_chans;
 126         u32                     h2c_chan_num;
 127         u32                     c2h_chan_num;
 128         u32                     irq_start;
 129         u32                     irq_num;
 130         u32                     status;
 131 };
 132
 133 #define xdma_err(xdev, fmt, args...)                                    \
 134         dev_err(&(xdev)->pdev->dev, fmt, ##args)
 135 #define XDMA_CHAN_NUM(_xd) ({                                           \
 136         typeof(_xd) (xd) = (_xd);                                       \
 137         ((xd)->h2c_chan_num + (xd)->c2h_chan_num); })
 138
 139 /* Get the last desc in a desc block */
 140 static inline void *xdma_blk_last_desc(struct xdma_desc_block *block)
 141 {
 142         return block->virt_addr + (XDMA_DESC_ADJACENT - 1) * XDMA_DESC_SIZE;
 143 }
 144
 145 /**
 146  * xdma_link_sg_desc_blocks - Link SG descriptor blocks for DMA transfer
 147  * @sw_desc: Tx descriptor pointer
 148  */
 149 static void xdma_link_sg_desc_blocks(struct xdma_desc *sw_desc)
 150 {
 151         struct xdma_desc_block *block;
 152         u32 last_blk_desc, desc_control;
 153         struct xdma_hw_desc *desc;
 154         int i;
 155
 156         desc_control = XDMA_DESC_CONTROL(XDMA_DESC_ADJACENT, 0);
 157         for (i = 1; i < sw_desc->dblk_num; i++) {
 158                 block = &sw_desc->desc_blocks[i - 1];
 159                 desc = xdma_blk_last_desc(block);
 160
 161                 if (!(i & XDMA_DESC_BLOCK_MASK)) {
 162                         desc->control = cpu_to_le32(XDMA_DESC_CONTROL_LAST);
 163                         continue;
 164                 }
 165                 desc->control = cpu_to_le32(desc_control);
 166                 desc->next_desc = cpu_to_le64(block[1].dma_addr);
 167         }
 168
 169         /* update the last block */
 170         last_blk_desc = (sw_desc->desc_num - 1) & XDMA_DESC_ADJACENT_MASK;
 171         if (((sw_desc->dblk_num - 1) & XDMA_DESC_BLOCK_MASK) > 0) {
 172                 block = &sw_desc->desc_blocks[sw_desc->dblk_num - 2];
 173                 desc = xdma_blk_last_desc(block);
 174                 desc_control = XDMA_DESC_CONTROL(last_blk_desc + 1, 0);
 175                 desc->control = cpu_to_le32(desc_control);
 176         }
 177
 178         block = &sw_desc->desc_blocks[sw_desc->dblk_num - 1];
 179         desc = block->virt_addr + last_blk_desc * XDMA_DESC_SIZE;
 180         desc->control = cpu_to_le32(XDMA_DESC_CONTROL_LAST);
 181 }
 182
 183 /**
 184  * xdma_link_cyclic_desc_blocks - Link cyclic descriptor blocks for DMA transfer
 185  * @sw_desc: Tx descriptor pointer
 186  */
 187 static void xdma_link_cyclic_desc_blocks(struct xdma_desc *sw_desc)
 188 {
 189         struct xdma_desc_block *block;
 190         struct xdma_hw_desc *desc;
 191         int i;
 192
 193         block = sw_desc->desc_blocks;
 194         for (i = 0; i < sw_desc->desc_num - 1; i++) {
 195                 desc = block->virt_addr + i * XDMA_DESC_SIZE;
 196                 desc->next_desc = cpu_to_le64(block->dma_addr + ((i + 1) * XDMA_DESC_SIZE));
 197         }
 198         desc = block->virt_addr + i * XDMA_DESC_SIZE;
 199         desc->next_desc = cpu_to_le64(block->dma_addr);
 200 }
 201
 202 static inline struct xdma_chan *to_xdma_chan(struct dma_chan *chan)
 203 {
 204         return container_of(chan, struct xdma_chan, vchan.chan);
 205 }
 206
 207 static inline struct xdma_desc *to_xdma_desc(struct virt_dma_desc *vdesc)
 208 {
 209         return container_of(vdesc, struct xdma_desc, vdesc);
 210 }
 211
 212 /**
 213  * xdma_channel_init - Initialize DMA channel registers
 214  * @chan: DMA channel pointer
 215  */
 216 static int xdma_channel_init(struct xdma_chan *chan)
 217 {
 218         struct xdma_device *xdev = chan->xdev_hdl;
 219         int ret;
 220
 221         ret = regmap_write(xdev->rmap, chan->base + XDMA_CHAN_CONTROL_W1C,
 222                            CHAN_CTRL_NON_INCR_ADDR);
 223         if (ret)
 224                 return ret;
 225
 226         ret = regmap_write(xdev->rmap, chan->base + XDMA_CHAN_INTR_ENABLE,
 227                            CHAN_IM_ALL);
 228         if (ret)
 229                 return ret;
 230
 231         return 0;
 232 }
 233
 234 /**
 235  * xdma_free_desc - Free descriptor
 236  * @vdesc: Virtual DMA descriptor
 237  */
 238 static void xdma_free_desc(struct virt_dma_desc *vdesc)
 239 {
 240         struct xdma_desc *sw_desc;
 241         int i;
 242
 243         sw_desc = to_xdma_desc(vdesc);
 244         for (i = 0; i < sw_desc->dblk_num; i++) {
 245                 if (!sw_desc->desc_blocks[i].virt_addr)
 246                         break;
 247                 dma_pool_free(sw_desc->chan->desc_pool,
 248                               sw_desc->desc_blocks[i].virt_addr,
 249                               sw_desc->desc_blocks[i].dma_addr);
 250         }
 251         kfree(sw_desc->desc_blocks);
 252         kfree(sw_desc);
 253 }
 254
 255 /**
 256  * xdma_alloc_desc - Allocate descriptor
 257  * @chan: DMA channel pointer
 258  * @desc_num: Number of hardware descriptors
 259  * @cyclic: Whether this is a cyclic transfer
 260  */
 261 static struct xdma_desc *
 262 xdma_alloc_desc(struct xdma_chan *chan, u32 desc_num, bool cyclic)
 263 {
 264         struct xdma_desc *sw_desc;
 265         struct xdma_hw_desc *desc;
 266         dma_addr_t dma_addr;
 267         u32 dblk_num;
 268         u32 control;
 269         void *addr;
 270         int i, j;
 271
 272         sw_desc = kzalloc(sizeof(*sw_desc), GFP_NOWAIT);
 273         if (!sw_desc)
 274                 return NULL;
 275
 276         sw_desc->chan = chan;
 277         sw_desc->desc_num = desc_num;
 278         sw_desc->cyclic = cyclic;
 279         dblk_num = DIV_ROUND_UP(desc_num, XDMA_DESC_ADJACENT);
 280         sw_desc->desc_blocks = kcalloc(dblk_num, sizeof(*sw_desc->desc_blocks),
 281                                        GFP_NOWAIT);
 282         if (!sw_desc->desc_blocks)
 283                 goto failed;
 284
 285         if (cyclic)
 286                 control = XDMA_DESC_CONTROL_CYCLIC;
 287         else
 288                 control = XDMA_DESC_CONTROL(1, 0);
 289
 290         sw_desc->dblk_num = dblk_num;
 291         for (i = 0; i < sw_desc->dblk_num; i++) {
 292                 addr = dma_pool_alloc(chan->desc_pool, GFP_NOWAIT, &dma_addr);
 293                 if (!addr)
 294                         goto failed;
 295
 296                 sw_desc->desc_blocks[i].virt_addr = addr;
 297                 sw_desc->desc_blocks[i].dma_addr = dma_addr;
 298                 for (j = 0, desc = addr; j < XDMA_DESC_ADJACENT; j++)
 299                         desc[j].control = cpu_to_le32(control);
 300         }
 301
 302         if (cyclic)
 303                 xdma_link_cyclic_desc_blocks(sw_desc);
 304         else
 305                 xdma_link_sg_desc_blocks(sw_desc);
 306
 307         return sw_desc;
 308
 309 failed:
 310         xdma_free_desc(&sw_desc->vdesc);
 311         return NULL;
 312 }
 313
 314 /**
 315  * xdma_xfer_start - Start DMA transfer
 316  * @xchan: DMA channel pointer
 317  */
 318 static int xdma_xfer_start(struct xdma_chan *xchan)
 319 {
 320         struct virt_dma_desc *vd = vchan_next_desc(&xchan->vchan);
 321         struct xdma_device *xdev = xchan->xdev_hdl;
 322         struct xdma_desc_block *block;
 323         u32 val, completed_blocks;
 324         struct xdma_desc *desc;
 325         int ret;
 326
 327         /*
 328          * check if there is not any submitted descriptor or channel is busy.
 329          * vchan lock should be held where this function is called.
 330          */
 331         if (!vd || xchan->busy)
 332                 return -EINVAL;
 333
 334         /* clear run stop bit to get ready for transfer */
 335         ret = regmap_write(xdev->rmap, xchan->base + XDMA_CHAN_CONTROL_W1C,
 336                            CHAN_CTRL_RUN_STOP);
 337         if (ret)
 338                 return ret;
 339
 340         desc = to_xdma_desc(vd);
 341         if (desc->dir != xchan->dir) {
 342                 xdma_err(xdev, "incorrect request direction");
 343                 return -EINVAL;
 344         }
 345
 346         /* set DMA engine to the first descriptor block */
 347         completed_blocks = desc->completed_desc_num / XDMA_DESC_ADJACENT;
 348         block = &desc->desc_blocks[completed_blocks];
 349         val = lower_32_bits(block->dma_addr);
 350         ret = regmap_write(xdev->rmap, xchan->base + XDMA_SGDMA_DESC_LO, val);
 351         if (ret)
 352                 return ret;
 353
 354         val = upper_32_bits(block->dma_addr);
 355         ret = regmap_write(xdev->rmap, xchan->base + XDMA_SGDMA_DESC_HI, val);
 356         if (ret)
 357                 return ret;
 358
 359         if (completed_blocks + 1 == desc->dblk_num)
 360                 val = (desc->desc_num - 1) & XDMA_DESC_ADJACENT_MASK;
 361         else
 362                 val = XDMA_DESC_ADJACENT - 1;
 363         ret = regmap_write(xdev->rmap, xchan->base + XDMA_SGDMA_DESC_ADJ, val);
 364         if (ret)
 365                 return ret;
 366
 367         /* kick off DMA transfer */
 368         ret = regmap_write(xdev->rmap, xchan->base + XDMA_CHAN_CONTROL,
 369                            CHAN_CTRL_START);
 370         if (ret)
 371                 return ret;
 372
 373         xchan->busy = true;
 374         return 0;
 375 }
 376
 377 /**
 378  * xdma_alloc_channels - Detect and allocate DMA channels
 379  * @xdev: DMA device pointer
 380  * @dir: Channel direction
 381  */
 382 static int xdma_alloc_channels(struct xdma_device *xdev,
 383                                enum dma_transfer_direction dir)
 384 {
 385         struct xdma_platdata *pdata = dev_get_platdata(&xdev->pdev->dev);
 386         struct xdma_chan **chans, *xchan;
 387         u32 base, identifier, target;
 388         u32 *chan_num;
 389         int i, j, ret;
 390
 391         if (dir == DMA_MEM_TO_DEV) {
 392                 base = XDMA_CHAN_H2C_OFFSET;
 393                 target = XDMA_CHAN_H2C_TARGET;
 394                 chans = &xdev->h2c_chans;
 395                 chan_num = &xdev->h2c_chan_num;
 396         } else if (dir == DMA_DEV_TO_MEM) {
 397                 base = XDMA_CHAN_C2H_OFFSET;
 398                 target = XDMA_CHAN_C2H_TARGET;
 399                 chans = &xdev->c2h_chans;
 400                 chan_num = &xdev->c2h_chan_num;
 401         } else {
 402                 xdma_err(xdev, "invalid direction specified");
 403                 return -EINVAL;
 404         }
 405
 406         /* detect number of available DMA channels */
 407         for (i = 0, *chan_num = 0; i < pdata->max_dma_channels; i++) {
 408                 ret = regmap_read(xdev->rmap, base + i * XDMA_CHAN_STRIDE,
 409                                   &identifier);
 410                 if (ret)
 411                         return ret;
 412
 413                 /* check if it is available DMA channel */
 414                 if (XDMA_CHAN_CHECK_TARGET(identifier, target))
 415                         (*chan_num)++;
 416         }
 417
 418         if (!*chan_num) {
 419                 xdma_err(xdev, "does not probe any channel");
 420                 return -EINVAL;
 421         }
 422
 423         *chans = devm_kcalloc(&xdev->pdev->dev, *chan_num, sizeof(**chans),
 424                               GFP_KERNEL);
 425         if (!*chans)
 426                 return -ENOMEM;
 427
 428         for (i = 0, j = 0; i < pdata->max_dma_channels; i++) {
 429                 ret = regmap_read(xdev->rmap, base + i * XDMA_CHAN_STRIDE,
 430                                   &identifier);
 431                 if (ret)
 432                         return ret;
 433
 434                 if (!XDMA_CHAN_CHECK_TARGET(identifier, target))
 435                         continue;
 436
 437                 if (j == *chan_num) {
 438                         xdma_err(xdev, "invalid channel number");
 439                         return -EIO;
 440                 }
 441
 442                 /* init channel structure and hardware */
 443                 xchan = &(*chans)[j];
 444                 xchan->xdev_hdl = xdev;
 445                 xchan->base = base + i * XDMA_CHAN_STRIDE;
 446                 xchan->dir = dir;
 447
 448                 ret = xdma_channel_init(xchan);
 449                 if (ret)
 450                         return ret;
 451                 xchan->vchan.desc_free = xdma_free_desc;
 452                 vchan_init(&xchan->vchan, &xdev->dma_dev);
 453
 454                 j++;
 455         }
 456
 457         dev_info(&xdev->pdev->dev, "configured %d %s channels", j,
 458                  (dir == DMA_MEM_TO_DEV) ? "H2C" : "C2H");
 459
 460         return 0;
 461 }
 462
 463 /**
 464  * xdma_issue_pending - Issue pending transactions
 465  * @chan: DMA channel pointer
 466  */
 467 static void xdma_issue_pending(struct dma_chan *chan)
 468 {
 469         struct xdma_chan *xdma_chan = to_xdma_chan(chan);
 470         unsigned long flags;
 471
 472         spin_lock_irqsave(&xdma_chan->vchan.lock, flags);
 473         if (vchan_issue_pending(&xdma_chan->vchan))
 474                 xdma_xfer_start(xdma_chan);
 475         spin_unlock_irqrestore(&xdma_chan->vchan.lock, flags);
 476 }
 477
 478 /**
 479  * xdma_prep_device_sg - prepare a descriptor for a DMA transaction
 480  * @chan: DMA channel pointer
 481  * @sgl: Transfer scatter gather list
 482  * @sg_len: Length of scatter gather list
 483  * @dir: Transfer direction
 484  * @flags: transfer ack flags
 485  * @context: APP words of the descriptor
 486  */
 487 static struct dma_async_tx_descriptor *
 488 xdma_prep_device_sg(struct dma_chan *chan, struct scatterlist *sgl,
 489                     unsigned int sg_len, enum dma_transfer_direction dir,
 490                     unsigned long flags, void *context)
 491 {
 492         struct xdma_chan *xdma_chan = to_xdma_chan(chan);
 493         struct dma_async_tx_descriptor *tx_desc;
 494         u32 desc_num = 0, i, len, rest;
 495         struct xdma_desc_block *dblk;
 496         struct xdma_hw_desc *desc;
 497         struct xdma_desc *sw_desc;
 498         u64 dev_addr, *src, *dst;
 499         struct scatterlist *sg;
 500         u64 addr;
 501
 502         for_each_sg(sgl, sg, sg_len, i)
 503                 desc_num += DIV_ROUND_UP(sg_dma_len(sg), XDMA_DESC_BLEN_MAX);
 504
 505         sw_desc = xdma_alloc_desc(xdma_chan, desc_num, false);
 506         if (!sw_desc)
 507                 return NULL;
 508         sw_desc->dir = dir;
 509
 510         if (dir == DMA_MEM_TO_DEV) {
 511                 dev_addr = xdma_chan->cfg.dst_addr;
 512                 src = &addr;
 513                 dst = &dev_addr;
 514         } else {
 515                 dev_addr = xdma_chan->cfg.src_addr;
 516                 src = &dev_addr;
 517                 dst = &addr;
 518         }
 519
 520         dblk = sw_desc->desc_blocks;
 521         desc = dblk->virt_addr;
 522         desc_num = 1;
 523         for_each_sg(sgl, sg, sg_len, i) {
 524                 addr = sg_dma_address(sg);
 525                 rest = sg_dma_len(sg);
 526
 527                 do {
 528                         len = min_t(u32, rest, XDMA_DESC_BLEN_MAX);
 529                         /* set hardware descriptor */
 530                         desc->bytes = cpu_to_le32(len);
 531                         desc->src_addr = cpu_to_le64(*src);
 532                         desc->dst_addr = cpu_to_le64(*dst);
 533
 534                         if (!(desc_num & XDMA_DESC_ADJACENT_MASK)) {
 535                                 dblk++;
 536                                 desc = dblk->virt_addr;
 537                         } else {
 538                                 desc++;
 539                         }
 540
 541                         desc_num++;
 542                         dev_addr += len;
 543                         addr += len;
 544                         rest -= len;
 545                 } while (rest);
 546         }
 547
 548         tx_desc = vchan_tx_prep(&xdma_chan->vchan, &sw_desc->vdesc, flags);
 549         if (!tx_desc)
 550                 goto failed;
 551
 552         return tx_desc;
 553
 554 failed:
 555         xdma_free_desc(&sw_desc->vdesc);
 556
 557         return NULL;
 558 }
 559
 560 /**
 561  * xdma_prep_dma_cyclic - prepare for cyclic DMA transactions
 562  * @chan: DMA channel pointer
 563  * @address: Device DMA address to access
 564  * @size: Total length to transfer
 565  * @period_size: Period size to use for each transfer
 566  * @dir: Transfer direction
 567  * @flags: Transfer ack flags
 568  */
 569 static struct dma_async_tx_descriptor *
 570 xdma_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t address,
 571                      size_t size, size_t period_size,
 572                      enum dma_transfer_direction dir,
 573                      unsigned long flags)
 574 {
 575         struct xdma_chan *xdma_chan = to_xdma_chan(chan);
 576         struct xdma_device *xdev = xdma_chan->xdev_hdl;
 577         unsigned int periods = size / period_size;
 578         struct dma_async_tx_descriptor *tx_desc;
 579         struct xdma_desc_block *dblk;
 580         struct xdma_hw_desc *desc;
 581         struct xdma_desc *sw_desc;
 582         unsigned int i;
 583
 584         /*
 585          * Simplify the whole logic by preventing an abnormally high number of
 586          * periods and periods size.
 587          */
 588         if (period_size > XDMA_DESC_BLEN_MAX) {
 589                 xdma_err(xdev, "period size limited to %lu bytes\n", XDMA_DESC_BLEN_MAX);
 590                 return NULL;
 591         }
 592
 593         if (periods > XDMA_DESC_ADJACENT) {
 594                 xdma_err(xdev, "number of periods limited to %u\n", XDMA_DESC_ADJACENT);
 595                 return NULL;
 596         }
 597
 598         sw_desc = xdma_alloc_desc(xdma_chan, periods, true);
 599         if (!sw_desc)
 600                 return NULL;
 601
 602         sw_desc->periods = periods;
 603         sw_desc->period_size = period_size;
 604         sw_desc->dir = dir;
 605
 606         dblk = sw_desc->desc_blocks;
 607         desc = dblk->virt_addr;
 608
 609         /* fill hardware descriptor */
 610         for (i = 0; i < periods; i++) {
 611                 desc->bytes = cpu_to_le32(period_size);
 612                 if (dir == DMA_MEM_TO_DEV) {
 613                         desc->src_addr = cpu_to_le64(address + i * period_size);
 614                         desc->dst_addr = cpu_to_le64(xdma_chan->cfg.dst_addr);
 615                 } else {
 616                         desc->src_addr = cpu_to_le64(xdma_chan->cfg.src_addr);
 617                         desc->dst_addr = cpu_to_le64(address + i * period_size);
 618                 }
 619
 620                 desc++;
 621         }
 622
 623         tx_desc = vchan_tx_prep(&xdma_chan->vchan, &sw_desc->vdesc, flags);
 624         if (!tx_desc)
 625                 goto failed;
 626
 627         return tx_desc;
 628
 629 failed:
 630         xdma_free_desc(&sw_desc->vdesc);
 631
 632         return NULL;
 633 }
 634
 635 /**
 636  * xdma_device_config - Configure the DMA channel
 637  * @chan: DMA channel
 638  * @cfg: channel configuration
 639  */
 640 static int xdma_device_config(struct dma_chan *chan,
 641                               struct dma_slave_config *cfg)
 642 {
 643         struct xdma_chan *xdma_chan = to_xdma_chan(chan);
 644
 645         memcpy(&xdma_chan->cfg, cfg, sizeof(*cfg));
 646
 647         return 0;
 648 }
 649
 650 /**
 651  * xdma_free_chan_resources - Free channel resources
 652  * @chan: DMA channel
 653  */
 654 static void xdma_free_chan_resources(struct dma_chan *chan)
 655 {
 656         struct xdma_chan *xdma_chan = to_xdma_chan(chan);
 657
 658         vchan_free_chan_resources(&xdma_chan->vchan);
 659         dma_pool_destroy(xdma_chan->desc_pool);
 660         xdma_chan->desc_pool = NULL;
 661 }
 662
 663 /**
 664  * xdma_alloc_chan_resources - Allocate channel resources
 665  * @chan: DMA channel
 666  */
 667 static int xdma_alloc_chan_resources(struct dma_chan *chan)
 668 {
 669         struct xdma_chan *xdma_chan = to_xdma_chan(chan);
 670         struct xdma_device *xdev = xdma_chan->xdev_hdl;
 671         struct device *dev = xdev->dma_dev.dev;
 672
 673         while (dev && !dev_is_pci(dev))
 674                 dev = dev->parent;
 675         if (!dev) {
 676                 xdma_err(xdev, "unable to find pci device");
 677                 return -EINVAL;
 678         }
 679
 680         xdma_chan->desc_pool = dma_pool_create(dma_chan_name(chan),
 681                                                dev, XDMA_DESC_BLOCK_SIZE,
 682                                                XDMA_DESC_BLOCK_ALIGN, 0);
 683         if (!xdma_chan->desc_pool) {
 684                 xdma_err(xdev, "unable to allocate descriptor pool");
 685                 return -ENOMEM;
 686         }
 687
 688         return 0;
 689 }
 690
 691 static enum dma_status xdma_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 692                                       struct dma_tx_state *state)
 693 {
 694         struct xdma_chan *xdma_chan = to_xdma_chan(chan);
 695         struct xdma_desc *desc = NULL;
 696         struct virt_dma_desc *vd;
 697         enum dma_status ret;
 698         unsigned long flags;
 699         unsigned int period_idx;
 700         u32 residue = 0;
 701
 702         ret = dma_cookie_status(chan, cookie, state);
 703         if (ret == DMA_COMPLETE)
 704                 return ret;
 705
 706         spin_lock_irqsave(&xdma_chan->vchan.lock, flags);
 707
 708         vd = vchan_find_desc(&xdma_chan->vchan, cookie);
 709         if (vd)
 710                 desc = to_xdma_desc(vd);
 711         if (!desc || !desc->cyclic) {
 712                 spin_unlock_irqrestore(&xdma_chan->vchan.lock, flags);
 713                 return ret;
 714         }
 715
 716         period_idx = desc->completed_desc_num % desc->periods;
 717         residue = (desc->periods - period_idx) * desc->period_size;
 718
 719         spin_unlock_irqrestore(&xdma_chan->vchan.lock, flags);
 720
 721         dma_set_residue(state, residue);
 722
 723         return ret;
 724 }
 725
 726 /**
 727  * xdma_channel_isr - XDMA channel interrupt handler
 728  * @irq: IRQ number
 729  * @dev_id: Pointer to the DMA channel structure
 730  */
 731 static irqreturn_t xdma_channel_isr(int irq, void *dev_id)
 732 {
 733         struct xdma_chan *xchan = dev_id;
 734         u32 complete_desc_num = 0;
 735         struct xdma_device *xdev;
 736         struct virt_dma_desc *vd;
 737         struct xdma_desc *desc;
 738         int ret;
 739         u32 st;
 740
 741         spin_lock(&xchan->vchan.lock);
 742
 743         /* get submitted request */
 744         vd = vchan_next_desc(&xchan->vchan);
 745         if (!vd)
 746                 goto out;
 747
 748         xchan->busy = false;
 749         desc = to_xdma_desc(vd);
 750         xdev = xchan->xdev_hdl;
 751
 752         ret = regmap_read(xdev->rmap, xchan->base + XDMA_CHAN_COMPLETED_DESC,
 753                           &complete_desc_num);
 754         if (ret)
 755                 goto out;
 756
 757         desc->completed_desc_num += complete_desc_num;
 758
 759         if (desc->cyclic) {
 760                 ret = regmap_read(xdev->rmap, xchan->base + XDMA_CHAN_STATUS,
 761                                   &st);
 762                 if (ret)
 763                         goto out;
 764
 765                 regmap_write(xdev->rmap, xchan->base + XDMA_CHAN_STATUS, st);
 766
 767                 vchan_cyclic_callback(vd);
 768                 goto out;
 769         }
 770
 771         /*
 772          * if all data blocks are transferred, remove and complete the request
 773          */
 774         if (desc->completed_desc_num == desc->desc_num) {
 775                 list_del(&vd->node);
 776                 vchan_cookie_complete(vd);
 777                 goto out;
 778         }
 779
 780         if (desc->completed_desc_num > desc->desc_num ||
 781             complete_desc_num != XDMA_DESC_BLOCK_NUM * XDMA_DESC_ADJACENT)
 782                 goto out;
 783
 784         /* transfer the rest of data (SG only) */
 785         xdma_xfer_start(xchan);
 786
 787 out:
 788         spin_unlock(&xchan->vchan.lock);
 789         return IRQ_HANDLED;
 790 }
 791
 792 /**
 793  * xdma_irq_fini - Uninitialize IRQ
 794  * @xdev: DMA device pointer
 795  */
 796 static void xdma_irq_fini(struct xdma_device *xdev)
 797 {
 798         int i;
 799
 800         /* disable interrupt */
 801         regmap_write(xdev->rmap, XDMA_IRQ_CHAN_INT_EN_W1C, ~0);
 802
 803         /* free irq handler */
 804         for (i = 0; i < xdev->h2c_chan_num; i++)
 805                 free_irq(xdev->h2c_chans[i].irq, &xdev->h2c_chans[i]);
 806
 807         for (i = 0; i < xdev->c2h_chan_num; i++)
 808                 free_irq(xdev->c2h_chans[i].irq, &xdev->c2h_chans[i]);
 809 }
 810
 811 /**
 812  * xdma_set_vector_reg - configure hardware IRQ registers
 813  * @xdev: DMA device pointer
 814  * @vec_tbl_start: Start of IRQ registers
 815  * @irq_start: Start of IRQ
 816  * @irq_num: Number of IRQ
 817  */
 818 static int xdma_set_vector_reg(struct xdma_device *xdev, u32 vec_tbl_start,
 819                                u32 irq_start, u32 irq_num)
 820 {
 821         u32 shift, i, val = 0;
 822         int ret;
 823
 824         /* Each IRQ register is 32 bit and contains 4 IRQs */
 825         while (irq_num > 0) {
 826                 for (i = 0; i < 4; i++) {
 827                         shift = XDMA_IRQ_VEC_SHIFT * i;
 828                         val |= irq_start << shift;
 829                         irq_start++;
 830                         irq_num--;
 831                         if (!irq_num)
 832                                 break;
 833                 }
 834
 835                 /* write IRQ register */
 836                 ret = regmap_write(xdev->rmap, vec_tbl_start, val);
 837                 if (ret)
 838                         return ret;
 839                 vec_tbl_start += sizeof(u32);
 840                 val = 0;
 841         }
 842
 843         return 0;
 844 }
 845
 846 /**
 847  * xdma_irq_init - initialize IRQs
 848  * @xdev: DMA device pointer
 849  */
 850 static int xdma_irq_init(struct xdma_device *xdev)
 851 {
 852         u32 irq = xdev->irq_start;
 853         u32 user_irq_start;
 854         int i, j, ret;
 855
 856         /* return failure if there are not enough IRQs */
 857         if (xdev->irq_num < XDMA_CHAN_NUM(xdev)) {
 858                 xdma_err(xdev, "not enough irq");
 859                 return -EINVAL;
 860         }
 861
 862         /* setup H2C interrupt handler */
 863         for (i = 0; i < xdev->h2c_chan_num; i++) {
 864                 ret = request_irq(irq, xdma_channel_isr, 0,
 865                                   "xdma-h2c-channel", &xdev->h2c_chans[i]);
 866                 if (ret) {
 867                         xdma_err(xdev, "H2C channel%d request irq%d failed: %d",
 868                                  i, irq, ret);
 869                         goto failed_init_h2c;
 870                 }
 871                 xdev->h2c_chans[i].irq = irq;
 872                 irq++;
 873         }
 874
 875         /* setup C2H interrupt handler */
 876         for (j = 0; j < xdev->c2h_chan_num; j++) {
 877                 ret = request_irq(irq, xdma_channel_isr, 0,
 878                                   "xdma-c2h-channel", &xdev->c2h_chans[j]);
 879                 if (ret) {
 880                         xdma_err(xdev, "C2H channel%d request irq%d failed: %d",
 881                                  j, irq, ret);
 882                         goto failed_init_c2h;
 883                 }
 884                 xdev->c2h_chans[j].irq = irq;
 885                 irq++;
 886         }
 887
 888         /* config hardware IRQ registers */
 889         ret = xdma_set_vector_reg(xdev, XDMA_IRQ_CHAN_VEC_NUM, 0,
 890                                   XDMA_CHAN_NUM(xdev));
 891         if (ret) {
 892                 xdma_err(xdev, "failed to set channel vectors: %d", ret);
 893                 goto failed_init_c2h;
 894         }
 895
 896         /* config user IRQ registers if needed */
 897         user_irq_start = XDMA_CHAN_NUM(xdev);
 898         if (xdev->irq_num > user_irq_start) {
 899                 ret = xdma_set_vector_reg(xdev, XDMA_IRQ_USER_VEC_NUM,
 900                                           user_irq_start,
 901                                           xdev->irq_num - user_irq_start);
 902                 if (ret) {
 903                         xdma_err(xdev, "failed to set user vectors: %d", ret);
 904                         goto failed_init_c2h;
 905                 }
 906         }
 907
 908         /* enable interrupt */
 909         ret = regmap_write(xdev->rmap, XDMA_IRQ_CHAN_INT_EN_W1S, ~0);
 910         if (ret)
 911                 goto failed_init_c2h;
 912
 913         return 0;
 914
 915 failed_init_c2h:
 916         while (j--)
 917                 free_irq(xdev->c2h_chans[j].irq, &xdev->c2h_chans[j]);
 918 failed_init_h2c:
 919         while (i--)
 920                 free_irq(xdev->h2c_chans[i].irq, &xdev->h2c_chans[i]);
 921
 922         return ret;
 923 }
 924
 925 static bool xdma_filter_fn(struct dma_chan *chan, void *param)
 926 {
 927         struct xdma_chan *xdma_chan = to_xdma_chan(chan);
 928         struct xdma_chan_info *chan_info = param;
 929
 930         return chan_info->dir == xdma_chan->dir;
 931 }
 932
 933 /**
 934  * xdma_disable_user_irq - Disable user interrupt
 935  * @pdev: Pointer to the platform_device structure
 936  * @irq_num: System IRQ number
 937  */
 938 void xdma_disable_user_irq(struct platform_device *pdev, u32 irq_num)
 939 {
 940         struct xdma_device *xdev = platform_get_drvdata(pdev);
 941         u32 index;
 942
 943         index = irq_num - xdev->irq_start;
 944         if (index < XDMA_CHAN_NUM(xdev) || index >= xdev->irq_num) {
 945                 xdma_err(xdev, "invalid user irq number");
 946                 return;
 947         }
 948         index -= XDMA_CHAN_NUM(xdev);
 949
 950         regmap_write(xdev->rmap, XDMA_IRQ_USER_INT_EN_W1C, 1 << index);
 951 }
 952 EXPORT_SYMBOL(xdma_disable_user_irq);
 953
 954 /**
 955  * xdma_enable_user_irq - Enable user logic interrupt
 956  * @pdev: Pointer to the platform_device structure
 957  * @irq_num: System IRQ number
 958  */
 959 int xdma_enable_user_irq(struct platform_device *pdev, u32 irq_num)
 960 {
 961         struct xdma_device *xdev = platform_get_drvdata(pdev);
 962         u32 index;
 963         int ret;
 964
 965         index = irq_num - xdev->irq_start;
 966         if (index < XDMA_CHAN_NUM(xdev) || index >= xdev->irq_num) {
 967                 xdma_err(xdev, "invalid user irq number");
 968                 return -EINVAL;
 969         }
 970         index -= XDMA_CHAN_NUM(xdev);
 971
 972         ret = regmap_write(xdev->rmap, XDMA_IRQ_USER_INT_EN_W1S, 1 << index);
 973         if (ret)
 974                 return ret;
 975
 976         return 0;
 977 }
 978 EXPORT_SYMBOL(xdma_enable_user_irq);
 979
 980 /**
 981  * xdma_get_user_irq - Get system IRQ number
 982  * @pdev: Pointer to the platform_device structure
 983  * @user_irq_index: User logic IRQ wire index
 984  *
 985  * Return: The system IRQ number allocated for the given wire index.
 986  */
 987 int xdma_get_user_irq(struct platform_device *pdev, u32 user_irq_index)
 988 {
 989         struct xdma_device *xdev = platform_get_drvdata(pdev);
 990
 991         if (XDMA_CHAN_NUM(xdev) + user_irq_index >= xdev->irq_num) {
 992                 xdma_err(xdev, "invalid user irq index");
 993                 return -EINVAL;
 994         }
 995
 996         return xdev->irq_start + XDMA_CHAN_NUM(xdev) + user_irq_index;
 997 }
 998 EXPORT_SYMBOL(xdma_get_user_irq);
 999
1000 /**
1001  * xdma_remove - Driver remove function
1002  * @pdev: Pointer to the platform_device structure
1003  */
1004 static void xdma_remove(struct platform_device *pdev)
1005 {
1006         struct xdma_device *xdev = platform_get_drvdata(pdev);
1007
1008         if (xdev->status & XDMA_DEV_STATUS_INIT_MSIX)
1009                 xdma_irq_fini(xdev);
1010
1011         if (xdev->status & XDMA_DEV_STATUS_REG_DMA)
1012                 dma_async_device_unregister(&xdev->dma_dev);
1013 }
1014
1015 /**
1016  * xdma_probe - Driver probe function
1017  * @pdev: Pointer to the platform_device structure
1018  */
1019 static int xdma_probe(struct platform_device *pdev)
1020 {
1021         struct xdma_platdata *pdata = dev_get_platdata(&pdev->dev);
1022         struct xdma_device *xdev;
1023         void __iomem *reg_base;
1024         struct resource *res;
1025         int ret = -ENODEV;
1026
1027         if (pdata->max_dma_channels > XDMA_MAX_CHANNELS) {
1028                 dev_err(&pdev->dev, "invalid max dma channels %d",
1029                         pdata->max_dma_channels);
1030                 return -EINVAL;
1031         }
1032
1033         xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
1034         if (!xdev)
1035                 return -ENOMEM;
1036
1037         platform_set_drvdata(pdev, xdev);
1038         xdev->pdev = pdev;
1039
1040         res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1041         if (!res) {
1042                 xdma_err(xdev, "failed to get irq resource");
1043                 goto failed;
1044         }
1045         xdev->irq_start = res->start;
1046         xdev->irq_num = resource_size(res);
1047
1048         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1049         if (!res) {
1050                 xdma_err(xdev, "failed to get io resource");
1051                 goto failed;
1052         }
1053
1054         reg_base = devm_ioremap_resource(&pdev->dev, res);
1055         if (IS_ERR(reg_base)) {
1056                 xdma_err(xdev, "ioremap failed");
1057                 goto failed;
1058         }
1059
1060         xdev->rmap = devm_regmap_init_mmio(&pdev->dev, reg_base,
1061                                            &xdma_regmap_config);
1062         if (!xdev->rmap) {
1063                 xdma_err(xdev, "config regmap failed: %d", ret);
1064                 goto failed;
1065         }
1066         INIT_LIST_HEAD(&xdev->dma_dev.channels);
1067
1068         ret = xdma_alloc_channels(xdev, DMA_MEM_TO_DEV);
1069         if (ret) {
1070                 xdma_err(xdev, "config H2C channels failed: %d", ret);
1071                 goto failed;
1072         }
1073
1074         ret = xdma_alloc_channels(xdev, DMA_DEV_TO_MEM);
1075         if (ret) {
1076                 xdma_err(xdev, "config C2H channels failed: %d", ret);
1077                 goto failed;
1078         }
1079
1080         dma_cap_set(DMA_SLAVE, xdev->dma_dev.cap_mask);
1081         dma_cap_set(DMA_PRIVATE, xdev->dma_dev.cap_mask);
1082         dma_cap_set(DMA_CYCLIC, xdev->dma_dev.cap_mask);
1083
1084         xdev->dma_dev.dev = &pdev->dev;
1085         xdev->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
1086         xdev->dma_dev.device_free_chan_resources = xdma_free_chan_resources;
1087         xdev->dma_dev.device_alloc_chan_resources = xdma_alloc_chan_resources;
1088         xdev->dma_dev.device_tx_status = xdma_tx_status;
1089         xdev->dma_dev.device_prep_slave_sg = xdma_prep_device_sg;
1090         xdev->dma_dev.device_config = xdma_device_config;
1091         xdev->dma_dev.device_issue_pending = xdma_issue_pending;
1092         xdev->dma_dev.filter.map = pdata->device_map;
1093         xdev->dma_dev.filter.mapcnt = pdata->device_map_cnt;
1094         xdev->dma_dev.filter.fn = xdma_filter_fn;
1095         xdev->dma_dev.device_prep_dma_cyclic = xdma_prep_dma_cyclic;
1096
1097         ret = dma_async_device_register(&xdev->dma_dev);
1098         if (ret) {
1099                 xdma_err(xdev, "failed to register Xilinx XDMA: %d", ret);
1100                 goto failed;
1101         }
1102         xdev->status |= XDMA_DEV_STATUS_REG_DMA;
1103
1104         ret = xdma_irq_init(xdev);
1105         if (ret) {
1106                 xdma_err(xdev, "failed to init msix: %d", ret);
1107                 goto failed;
1108         }
1109         xdev->status |= XDMA_DEV_STATUS_INIT_MSIX;
1110
1111         return 0;
1112
1113 failed:
1114         xdma_remove(pdev);
1115
1116         return ret;
1117 }
1118
1119 static const struct platform_device_id xdma_id_table[] = {
1120         { "xdma", 0},
1121         { },
1122 };
1123
1124 static struct platform_driver xdma_driver = {
1125         .driver         = {
1126                 .name = "xdma",
1127         },
1128         .id_table       = xdma_id_table,
1129         .probe          = xdma_probe,
1130         .remove_new     = xdma_remove,
1131 };
1132
1133 module_platform_driver(xdma_driver);
1134
1135 MODULE_DESCRIPTION("AMD XDMA driver");
1136 MODULE_AUTHOR("XRT Team <runtimeca39d@amd.com>");
1137 MODULE_LICENSE("GPL");