drivers/dma/tegra20-apb-dma.c

   1 /*
   2  * DMA driver for Nvidia's Tegra20 APB DMA controller.
   3  *
   4  * Copyright (c) 2012-2013, NVIDIA CORPORATION.  All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <linux/bitops.h>
  20 #include <linux/clk.h>
  21 #include <linux/delay.h>
  22 #include <linux/dmaengine.h>
  23 #include <linux/dma-mapping.h>
  24 #include <linux/err.h>
  25 #include <linux/init.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/io.h>
  28 #include <linux/mm.h>
  29 #include <linux/module.h>
  30 #include <linux/of.h>
  31 #include <linux/of_device.h>
  32 #include <linux/of_dma.h>
  33 #include <linux/platform_device.h>
  34 #include <linux/pm.h>
  35 #include <linux/pm_runtime.h>
  36 #include <linux/reset.h>
  37 #include <linux/slab.h>
  38
  39 #include "dmaengine.h"
  40
  41 #define TEGRA_APBDMA_GENERAL                    0x0
  42 #define TEGRA_APBDMA_GENERAL_ENABLE             BIT(31)
  43
  44 #define TEGRA_APBDMA_CONTROL                    0x010
  45 #define TEGRA_APBDMA_IRQ_MASK                   0x01c
  46 #define TEGRA_APBDMA_IRQ_MASK_SET               0x020
  47
  48 /* CSR register */
  49 #define TEGRA_APBDMA_CHAN_CSR                   0x00
  50 #define TEGRA_APBDMA_CSR_ENB                    BIT(31)
  51 #define TEGRA_APBDMA_CSR_IE_EOC                 BIT(30)
  52 #define TEGRA_APBDMA_CSR_HOLD                   BIT(29)
  53 #define TEGRA_APBDMA_CSR_DIR                    BIT(28)
  54 #define TEGRA_APBDMA_CSR_ONCE                   BIT(27)
  55 #define TEGRA_APBDMA_CSR_FLOW                   BIT(21)
  56 #define TEGRA_APBDMA_CSR_REQ_SEL_SHIFT          16
  57 #define TEGRA_APBDMA_CSR_REQ_SEL_MASK           0x1F
  58 #define TEGRA_APBDMA_CSR_WCOUNT_MASK            0xFFFC
  59
  60 /* STATUS register */
  61 #define TEGRA_APBDMA_CHAN_STATUS                0x004
  62 #define TEGRA_APBDMA_STATUS_BUSY                BIT(31)
  63 #define TEGRA_APBDMA_STATUS_ISE_EOC             BIT(30)
  64 #define TEGRA_APBDMA_STATUS_HALT                BIT(29)
  65 #define TEGRA_APBDMA_STATUS_PING_PONG           BIT(28)
  66 #define TEGRA_APBDMA_STATUS_COUNT_SHIFT         2
  67 #define TEGRA_APBDMA_STATUS_COUNT_MASK          0xFFFC
  68
  69 #define TEGRA_APBDMA_CHAN_CSRE                  0x00C
  70 #define TEGRA_APBDMA_CHAN_CSRE_PAUSE            (1 << 31)
  71
  72 /* AHB memory address */
  73 #define TEGRA_APBDMA_CHAN_AHBPTR                0x010
  74
  75 /* AHB sequence register */
  76 #define TEGRA_APBDMA_CHAN_AHBSEQ                0x14
  77 #define TEGRA_APBDMA_AHBSEQ_INTR_ENB            BIT(31)
  78 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_8         (0 << 28)
  79 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_16        (1 << 28)
  80 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32        (2 << 28)
  81 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_64        (3 << 28)
  82 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_128       (4 << 28)
  83 #define TEGRA_APBDMA_AHBSEQ_DATA_SWAP           BIT(27)
  84 #define TEGRA_APBDMA_AHBSEQ_BURST_1             (4 << 24)
  85 #define TEGRA_APBDMA_AHBSEQ_BURST_4             (5 << 24)
  86 #define TEGRA_APBDMA_AHBSEQ_BURST_8             (6 << 24)
  87 #define TEGRA_APBDMA_AHBSEQ_DBL_BUF             BIT(19)
  88 #define TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT          16
  89 #define TEGRA_APBDMA_AHBSEQ_WRAP_NONE           0
  90
  91 /* APB address */
  92 #define TEGRA_APBDMA_CHAN_APBPTR                0x018
  93
  94 /* APB sequence register */
  95 #define TEGRA_APBDMA_CHAN_APBSEQ                0x01c
  96 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8         (0 << 28)
  97 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16        (1 << 28)
  98 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32        (2 << 28)
  99 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64        (3 << 28)
 100 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_128       (4 << 28)
 101 #define TEGRA_APBDMA_APBSEQ_DATA_SWAP           BIT(27)
 102 #define TEGRA_APBDMA_APBSEQ_WRAP_WORD_1         (1 << 16)
 103
 104 /* Tegra148 specific registers */
 105 #define TEGRA_APBDMA_CHAN_WCOUNT                0x20
 106
 107 #define TEGRA_APBDMA_CHAN_WORD_TRANSFER         0x24
 108
 109 /*
 110  * If any burst is in flight and DMA paused then this is the time to complete
 111  * on-flight burst and update DMA status register.
 112  */
 113 #define TEGRA_APBDMA_BURST_COMPLETE_TIME        20
 114
 115 /* Channel base address offset from APBDMA base address */
 116 #define TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET    0x1000
 117
 118 #define TEGRA_APBDMA_SLAVE_ID_INVALID   (TEGRA_APBDMA_CSR_REQ_SEL_MASK + 1)
 119
 120 struct tegra_dma;
 121
 122 /*
 123  * tegra_dma_chip_data Tegra chip specific DMA data
 124  * @nr_channels: Number of channels available in the controller.
 125  * @channel_reg_size: Channel register size/stride.
 126  * @max_dma_count: Maximum DMA transfer count supported by DMA controller.
 127  * @support_channel_pause: Support channel wise pause of dma.
 128  * @support_separate_wcount_reg: Support separate word count register.
 129  */
 130 struct tegra_dma_chip_data {
 131         int nr_channels;
 132         int channel_reg_size;
 133         int max_dma_count;
 134         bool support_channel_pause;
 135         bool support_separate_wcount_reg;
 136 };
 137
 138 /* DMA channel registers */
 139 struct tegra_dma_channel_regs {
 140         unsigned long   csr;
 141         unsigned long   ahb_ptr;
 142         unsigned long   apb_ptr;
 143         unsigned long   ahb_seq;
 144         unsigned long   apb_seq;
 145         unsigned long   wcount;
 146 };
 147
 148 /*
 149  * tegra_dma_sg_req: Dma request details to configure hardware. This
 150  * contains the details for one transfer to configure DMA hw.
 151  * The client's request for data transfer can be broken into multiple
 152  * sub-transfer as per requester details and hw support.
 153  * This sub transfer get added in the list of transfer and point to Tegra
 154  * DMA descriptor which manages the transfer details.
 155  */
 156 struct tegra_dma_sg_req {
 157         struct tegra_dma_channel_regs   ch_regs;
 158         int                             req_len;
 159         bool                            configured;
 160         bool                            last_sg;
 161         struct list_head                node;
 162         struct tegra_dma_desc           *dma_desc;
 163 };
 164
 165 /*
 166  * tegra_dma_desc: Tegra DMA descriptors which manages the client requests.
 167  * This descriptor keep track of transfer status, callbacks and request
 168  * counts etc.
 169  */
 170 struct tegra_dma_desc {
 171         struct dma_async_tx_descriptor  txd;
 172         int                             bytes_requested;
 173         int                             bytes_transferred;
 174         enum dma_status                 dma_status;
 175         struct list_head                node;
 176         struct list_head                tx_list;
 177         struct list_head                cb_node;
 178         int                             cb_count;
 179 };
 180
 181 struct tegra_dma_channel;
 182
 183 typedef void (*dma_isr_handler)(struct tegra_dma_channel *tdc,
 184                                 bool to_terminate);
 185
 186 /* tegra_dma_channel: Channel specific information */
 187 struct tegra_dma_channel {
 188         struct dma_chan         dma_chan;
 189         char                    name[30];
 190         bool                    config_init;
 191         int                     id;
 192         int                     irq;
 193         void __iomem            *chan_addr;
 194         spinlock_t              lock;
 195         bool                    busy;
 196         struct tegra_dma        *tdma;
 197         bool                    cyclic;
 198
 199         /* Different lists for managing the requests */
 200         struct list_head        free_sg_req;
 201         struct list_head        pending_sg_req;
 202         struct list_head        free_dma_desc;
 203         struct list_head        cb_desc;
 204
 205         /* ISR handler and tasklet for bottom half of isr handling */
 206         dma_isr_handler         isr_handler;
 207         struct tasklet_struct   tasklet;
 208
 209         /* Channel-slave specific configuration */
 210         unsigned int slave_id;
 211         struct dma_slave_config dma_sconfig;
 212         struct tegra_dma_channel_regs   channel_reg;
 213 };
 214
 215 /* tegra_dma: Tegra DMA specific information */
 216 struct tegra_dma {
 217         struct dma_device               dma_dev;
 218         struct device                   *dev;
 219         struct clk                      *dma_clk;
 220         struct reset_control            *rst;
 221         spinlock_t                      global_lock;
 222         void __iomem                    *base_addr;
 223         const struct tegra_dma_chip_data *chip_data;
 224
 225         /*
 226          * Counter for managing global pausing of the DMA controller.
 227          * Only applicable for devices that don't support individual
 228          * channel pausing.
 229          */
 230         u32                             global_pause_count;
 231
 232         /* Some register need to be cache before suspend */
 233         u32                             reg_gen;
 234
 235         /* Last member of the structure */
 236         struct tegra_dma_channel channels[0];
 237 };
 238
 239 static inline void tdma_write(struct tegra_dma *tdma, u32 reg, u32 val)
 240 {
 241         writel(val, tdma->base_addr + reg);
 242 }
 243
 244 static inline u32 tdma_read(struct tegra_dma *tdma, u32 reg)
 245 {
 246         return readl(tdma->base_addr + reg);
 247 }
 248
 249 static inline void tdc_write(struct tegra_dma_channel *tdc,
 250                 u32 reg, u32 val)
 251 {
 252         writel(val, tdc->chan_addr + reg);
 253 }
 254
 255 static inline u32 tdc_read(struct tegra_dma_channel *tdc, u32 reg)
 256 {
 257         return readl(tdc->chan_addr + reg);
 258 }
 259
 260 static inline struct tegra_dma_channel *to_tegra_dma_chan(struct dma_chan *dc)
 261 {
 262         return container_of(dc, struct tegra_dma_channel, dma_chan);
 263 }
 264
 265 static inline struct tegra_dma_desc *txd_to_tegra_dma_desc(
 266                 struct dma_async_tx_descriptor *td)
 267 {
 268         return container_of(td, struct tegra_dma_desc, txd);
 269 }
 270
 271 static inline struct device *tdc2dev(struct tegra_dma_channel *tdc)
 272 {
 273         return &tdc->dma_chan.dev->device;
 274 }
 275
 276 static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *tx);
 277 static int tegra_dma_runtime_suspend(struct device *dev);
 278 static int tegra_dma_runtime_resume(struct device *dev);
 279
 280 /* Get DMA desc from free list, if not there then allocate it.  */
 281 static struct tegra_dma_desc *tegra_dma_desc_get(
 282                 struct tegra_dma_channel *tdc)
 283 {
 284         struct tegra_dma_desc *dma_desc;
 285         unsigned long flags;
 286
 287         spin_lock_irqsave(&tdc->lock, flags);
 288
 289         /* Do not allocate if desc are waiting for ack */
 290         list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
 291                 if (async_tx_test_ack(&dma_desc->txd)) {
 292                         list_del(&dma_desc->node);
 293                         spin_unlock_irqrestore(&tdc->lock, flags);
 294                         dma_desc->txd.flags = 0;
 295                         return dma_desc;
 296                 }
 297         }
 298
 299         spin_unlock_irqrestore(&tdc->lock, flags);
 300
 301         /* Allocate DMA desc */
 302         dma_desc = kzalloc(sizeof(*dma_desc), GFP_NOWAIT);
 303         if (!dma_desc)
 304                 return NULL;
 305
 306         dma_async_tx_descriptor_init(&dma_desc->txd, &tdc->dma_chan);
 307         dma_desc->txd.tx_submit = tegra_dma_tx_submit;
 308         dma_desc->txd.flags = 0;
 309         return dma_desc;
 310 }
 311
 312 static void tegra_dma_desc_put(struct tegra_dma_channel *tdc,
 313                 struct tegra_dma_desc *dma_desc)
 314 {
 315         unsigned long flags;
 316
 317         spin_lock_irqsave(&tdc->lock, flags);
 318         if (!list_empty(&dma_desc->tx_list))
 319                 list_splice_init(&dma_desc->tx_list, &tdc->free_sg_req);
 320         list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
 321         spin_unlock_irqrestore(&tdc->lock, flags);
 322 }
 323
 324 static struct tegra_dma_sg_req *tegra_dma_sg_req_get(
 325                 struct tegra_dma_channel *tdc)
 326 {
 327         struct tegra_dma_sg_req *sg_req = NULL;
 328         unsigned long flags;
 329
 330         spin_lock_irqsave(&tdc->lock, flags);
 331         if (!list_empty(&tdc->free_sg_req)) {
 332                 sg_req = list_first_entry(&tdc->free_sg_req,
 333                                         typeof(*sg_req), node);
 334                 list_del(&sg_req->node);
 335                 spin_unlock_irqrestore(&tdc->lock, flags);
 336                 return sg_req;
 337         }
 338         spin_unlock_irqrestore(&tdc->lock, flags);
 339
 340         sg_req = kzalloc(sizeof(struct tegra_dma_sg_req), GFP_NOWAIT);
 341
 342         return sg_req;
 343 }
 344
 345 static int tegra_dma_slave_config(struct dma_chan *dc,
 346                 struct dma_slave_config *sconfig)
 347 {
 348         struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 349
 350         if (!list_empty(&tdc->pending_sg_req)) {
 351                 dev_err(tdc2dev(tdc), "Configuration not allowed\n");
 352                 return -EBUSY;
 353         }
 354
 355         memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig));
 356         if (tdc->slave_id == TEGRA_APBDMA_SLAVE_ID_INVALID) {
 357                 if (sconfig->slave_id > TEGRA_APBDMA_CSR_REQ_SEL_MASK)
 358                         return -EINVAL;
 359                 tdc->slave_id = sconfig->slave_id;
 360         }
 361         tdc->config_init = true;
 362         return 0;
 363 }
 364
 365 static void tegra_dma_global_pause(struct tegra_dma_channel *tdc,
 366         bool wait_for_burst_complete)
 367 {
 368         struct tegra_dma *tdma = tdc->tdma;
 369
 370         spin_lock(&tdma->global_lock);
 371
 372         if (tdc->tdma->global_pause_count == 0) {
 373                 tdma_write(tdma, TEGRA_APBDMA_GENERAL, 0);
 374                 if (wait_for_burst_complete)
 375                         udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
 376         }
 377
 378         tdc->tdma->global_pause_count++;
 379
 380         spin_unlock(&tdma->global_lock);
 381 }
 382
 383 static void tegra_dma_global_resume(struct tegra_dma_channel *tdc)
 384 {
 385         struct tegra_dma *tdma = tdc->tdma;
 386
 387         spin_lock(&tdma->global_lock);
 388
 389         if (WARN_ON(tdc->tdma->global_pause_count == 0))
 390                 goto out;
 391
 392         if (--tdc->tdma->global_pause_count == 0)
 393                 tdma_write(tdma, TEGRA_APBDMA_GENERAL,
 394                            TEGRA_APBDMA_GENERAL_ENABLE);
 395
 396 out:
 397         spin_unlock(&tdma->global_lock);
 398 }
 399
 400 static void tegra_dma_pause(struct tegra_dma_channel *tdc,
 401         bool wait_for_burst_complete)
 402 {
 403         struct tegra_dma *tdma = tdc->tdma;
 404
 405         if (tdma->chip_data->support_channel_pause) {
 406                 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE,
 407                                 TEGRA_APBDMA_CHAN_CSRE_PAUSE);
 408                 if (wait_for_burst_complete)
 409                         udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
 410         } else {
 411                 tegra_dma_global_pause(tdc, wait_for_burst_complete);
 412         }
 413 }
 414
 415 static void tegra_dma_resume(struct tegra_dma_channel *tdc)
 416 {
 417         struct tegra_dma *tdma = tdc->tdma;
 418
 419         if (tdma->chip_data->support_channel_pause) {
 420                 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE, 0);
 421         } else {
 422                 tegra_dma_global_resume(tdc);
 423         }
 424 }
 425
 426 static void tegra_dma_stop(struct tegra_dma_channel *tdc)
 427 {
 428         u32 csr;
 429         u32 status;
 430
 431         /* Disable interrupts */
 432         csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR);
 433         csr &= ~TEGRA_APBDMA_CSR_IE_EOC;
 434         tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr);
 435
 436         /* Disable DMA */
 437         csr &= ~TEGRA_APBDMA_CSR_ENB;
 438         tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr);
 439
 440         /* Clear interrupt status if it is there */
 441         status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 442         if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
 443                 dev_dbg(tdc2dev(tdc), "%s():clearing interrupt\n", __func__);
 444                 tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status);
 445         }
 446         tdc->busy = false;
 447 }
 448
 449 static void tegra_dma_start(struct tegra_dma_channel *tdc,
 450                 struct tegra_dma_sg_req *sg_req)
 451 {
 452         struct tegra_dma_channel_regs *ch_regs = &sg_req->ch_regs;
 453
 454         tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, ch_regs->csr);
 455         tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_regs->apb_seq);
 456         tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_regs->apb_ptr);
 457         tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_regs->ahb_seq);
 458         tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_regs->ahb_ptr);
 459         if (tdc->tdma->chip_data->support_separate_wcount_reg)
 460                 tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT, ch_regs->wcount);
 461
 462         /* Start DMA */
 463         tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
 464                                 ch_regs->csr | TEGRA_APBDMA_CSR_ENB);
 465 }
 466
 467 static void tegra_dma_configure_for_next(struct tegra_dma_channel *tdc,
 468                 struct tegra_dma_sg_req *nsg_req)
 469 {
 470         unsigned long status;
 471
 472         /*
 473          * The DMA controller reloads the new configuration for next transfer
 474          * after last burst of current transfer completes.
 475          * If there is no IEC status then this makes sure that last burst
 476          * has not be completed. There may be case that last burst is on
 477          * flight and so it can complete but because DMA is paused, it
 478          * will not generates interrupt as well as not reload the new
 479          * configuration.
 480          * If there is already IEC status then interrupt handler need to
 481          * load new configuration.
 482          */
 483         tegra_dma_pause(tdc, false);
 484         status  = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 485
 486         /*
 487          * If interrupt is pending then do nothing as the ISR will handle
 488          * the programing for new request.
 489          */
 490         if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
 491                 dev_err(tdc2dev(tdc),
 492                         "Skipping new configuration as interrupt is pending\n");
 493                 tegra_dma_resume(tdc);
 494                 return;
 495         }
 496
 497         /* Safe to program new configuration */
 498         tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, nsg_req->ch_regs.apb_ptr);
 499         tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, nsg_req->ch_regs.ahb_ptr);
 500         if (tdc->tdma->chip_data->support_separate_wcount_reg)
 501                 tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT,
 502                                                 nsg_req->ch_regs.wcount);
 503         tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
 504                                 nsg_req->ch_regs.csr | TEGRA_APBDMA_CSR_ENB);
 505         nsg_req->configured = true;
 506
 507         tegra_dma_resume(tdc);
 508 }
 509
 510 static void tdc_start_head_req(struct tegra_dma_channel *tdc)
 511 {
 512         struct tegra_dma_sg_req *sg_req;
 513
 514         if (list_empty(&tdc->pending_sg_req))
 515                 return;
 516
 517         sg_req = list_first_entry(&tdc->pending_sg_req,
 518                                         typeof(*sg_req), node);
 519         tegra_dma_start(tdc, sg_req);
 520         sg_req->configured = true;
 521         tdc->busy = true;
 522 }
 523
 524 static void tdc_configure_next_head_desc(struct tegra_dma_channel *tdc)
 525 {
 526         struct tegra_dma_sg_req *hsgreq;
 527         struct tegra_dma_sg_req *hnsgreq;
 528
 529         if (list_empty(&tdc->pending_sg_req))
 530                 return;
 531
 532         hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node);
 533         if (!list_is_last(&hsgreq->node, &tdc->pending_sg_req)) {
 534                 hnsgreq = list_first_entry(&hsgreq->node,
 535                                         typeof(*hnsgreq), node);
 536                 tegra_dma_configure_for_next(tdc, hnsgreq);
 537         }
 538 }
 539
 540 static inline int get_current_xferred_count(struct tegra_dma_channel *tdc,
 541         struct tegra_dma_sg_req *sg_req, unsigned long status)
 542 {
 543         return sg_req->req_len - (status & TEGRA_APBDMA_STATUS_COUNT_MASK) - 4;
 544 }
 545
 546 static void tegra_dma_abort_all(struct tegra_dma_channel *tdc)
 547 {
 548         struct tegra_dma_sg_req *sgreq;
 549         struct tegra_dma_desc *dma_desc;
 550
 551         while (!list_empty(&tdc->pending_sg_req)) {
 552                 sgreq = list_first_entry(&tdc->pending_sg_req,
 553                                                 typeof(*sgreq), node);
 554                 list_move_tail(&sgreq->node, &tdc->free_sg_req);
 555                 if (sgreq->last_sg) {
 556                         dma_desc = sgreq->dma_desc;
 557                         dma_desc->dma_status = DMA_ERROR;
 558                         list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
 559
 560                         /* Add in cb list if it is not there. */
 561                         if (!dma_desc->cb_count)
 562                                 list_add_tail(&dma_desc->cb_node,
 563                                                         &tdc->cb_desc);
 564                         dma_desc->cb_count++;
 565                 }
 566         }
 567         tdc->isr_handler = NULL;
 568 }
 569
 570 static bool handle_continuous_head_request(struct tegra_dma_channel *tdc,
 571                 struct tegra_dma_sg_req *last_sg_req, bool to_terminate)
 572 {
 573         struct tegra_dma_sg_req *hsgreq = NULL;
 574
 575         if (list_empty(&tdc->pending_sg_req)) {
 576                 dev_err(tdc2dev(tdc), "Dma is running without req\n");
 577                 tegra_dma_stop(tdc);
 578                 return false;
 579         }
 580
 581         /*
 582          * Check that head req on list should be in flight.
 583          * If it is not in flight then abort transfer as
 584          * looping of transfer can not continue.
 585          */
 586         hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node);
 587         if (!hsgreq->configured) {
 588                 tegra_dma_stop(tdc);
 589                 dev_err(tdc2dev(tdc), "Error in dma transfer, aborting dma\n");
 590                 tegra_dma_abort_all(tdc);
 591                 return false;
 592         }
 593
 594         /* Configure next request */
 595         if (!to_terminate)
 596                 tdc_configure_next_head_desc(tdc);
 597         return true;
 598 }
 599
 600 static void handle_once_dma_done(struct tegra_dma_channel *tdc,
 601         bool to_terminate)
 602 {
 603         struct tegra_dma_sg_req *sgreq;
 604         struct tegra_dma_desc *dma_desc;
 605
 606         tdc->busy = false;
 607         sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
 608         dma_desc = sgreq->dma_desc;
 609         dma_desc->bytes_transferred += sgreq->req_len;
 610
 611         list_del(&sgreq->node);
 612         if (sgreq->last_sg) {
 613                 dma_desc->dma_status = DMA_COMPLETE;
 614                 dma_cookie_complete(&dma_desc->txd);
 615                 if (!dma_desc->cb_count)
 616                         list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
 617                 dma_desc->cb_count++;
 618                 list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
 619         }
 620         list_add_tail(&sgreq->node, &tdc->free_sg_req);
 621
 622         /* Do not start DMA if it is going to be terminate */
 623         if (to_terminate || list_empty(&tdc->pending_sg_req))
 624                 return;
 625
 626         tdc_start_head_req(tdc);
 627 }
 628
 629 static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc,
 630                 bool to_terminate)
 631 {
 632         struct tegra_dma_sg_req *sgreq;
 633         struct tegra_dma_desc *dma_desc;
 634         bool st;
 635
 636         sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
 637         dma_desc = sgreq->dma_desc;
 638         dma_desc->bytes_transferred += sgreq->req_len;
 639
 640         /* Callback need to be call */
 641         if (!dma_desc->cb_count)
 642                 list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
 643         dma_desc->cb_count++;
 644
 645         /* If not last req then put at end of pending list */
 646         if (!list_is_last(&sgreq->node, &tdc->pending_sg_req)) {
 647                 list_move_tail(&sgreq->node, &tdc->pending_sg_req);
 648                 sgreq->configured = false;
 649                 st = handle_continuous_head_request(tdc, sgreq, to_terminate);
 650                 if (!st)
 651                         dma_desc->dma_status = DMA_ERROR;
 652         }
 653 }
 654
 655 static void tegra_dma_tasklet(unsigned long data)
 656 {
 657         struct tegra_dma_channel *tdc = (struct tegra_dma_channel *)data;
 658         dma_async_tx_callback callback = NULL;
 659         void *callback_param = NULL;
 660         struct tegra_dma_desc *dma_desc;
 661         unsigned long flags;
 662         int cb_count;
 663
 664         spin_lock_irqsave(&tdc->lock, flags);
 665         while (!list_empty(&tdc->cb_desc)) {
 666                 dma_desc  = list_first_entry(&tdc->cb_desc,
 667                                         typeof(*dma_desc), cb_node);
 668                 list_del(&dma_desc->cb_node);
 669                 callback = dma_desc->txd.callback;
 670                 callback_param = dma_desc->txd.callback_param;
 671                 cb_count = dma_desc->cb_count;
 672                 dma_desc->cb_count = 0;
 673                 spin_unlock_irqrestore(&tdc->lock, flags);
 674                 while (cb_count-- && callback)
 675                         callback(callback_param);
 676                 spin_lock_irqsave(&tdc->lock, flags);
 677         }
 678         spin_unlock_irqrestore(&tdc->lock, flags);
 679 }
 680
 681 static irqreturn_t tegra_dma_isr(int irq, void *dev_id)
 682 {
 683         struct tegra_dma_channel *tdc = dev_id;
 684         unsigned long status;
 685         unsigned long flags;
 686
 687         spin_lock_irqsave(&tdc->lock, flags);
 688
 689         status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 690         if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
 691                 tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status);
 692                 tdc->isr_handler(tdc, false);
 693                 tasklet_schedule(&tdc->tasklet);
 694                 spin_unlock_irqrestore(&tdc->lock, flags);
 695                 return IRQ_HANDLED;
 696         }
 697
 698         spin_unlock_irqrestore(&tdc->lock, flags);
 699         dev_info(tdc2dev(tdc),
 700                 "Interrupt already served status 0x%08lx\n", status);
 701         return IRQ_NONE;
 702 }
 703
 704 static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *txd)
 705 {
 706         struct tegra_dma_desc *dma_desc = txd_to_tegra_dma_desc(txd);
 707         struct tegra_dma_channel *tdc = to_tegra_dma_chan(txd->chan);
 708         unsigned long flags;
 709         dma_cookie_t cookie;
 710
 711         spin_lock_irqsave(&tdc->lock, flags);
 712         dma_desc->dma_status = DMA_IN_PROGRESS;
 713         cookie = dma_cookie_assign(&dma_desc->txd);
 714         list_splice_tail_init(&dma_desc->tx_list, &tdc->pending_sg_req);
 715         spin_unlock_irqrestore(&tdc->lock, flags);
 716         return cookie;
 717 }
 718
 719 static void tegra_dma_issue_pending(struct dma_chan *dc)
 720 {
 721         struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 722         unsigned long flags;
 723
 724         spin_lock_irqsave(&tdc->lock, flags);
 725         if (list_empty(&tdc->pending_sg_req)) {
 726                 dev_err(tdc2dev(tdc), "No DMA request\n");
 727                 goto end;
 728         }
 729         if (!tdc->busy) {
 730                 tdc_start_head_req(tdc);
 731
 732                 /* Continuous single mode: Configure next req */
 733                 if (tdc->cyclic) {
 734                         /*
 735                          * Wait for 1 burst time for configure DMA for
 736                          * next transfer.
 737                          */
 738                         udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
 739                         tdc_configure_next_head_desc(tdc);
 740                 }
 741         }
 742 end:
 743         spin_unlock_irqrestore(&tdc->lock, flags);
 744 }
 745
 746 static int tegra_dma_terminate_all(struct dma_chan *dc)
 747 {
 748         struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 749         struct tegra_dma_sg_req *sgreq;
 750         struct tegra_dma_desc *dma_desc;
 751         unsigned long flags;
 752         unsigned long status;
 753         unsigned long wcount;
 754         bool was_busy;
 755
 756         spin_lock_irqsave(&tdc->lock, flags);
 757         if (list_empty(&tdc->pending_sg_req)) {
 758                 spin_unlock_irqrestore(&tdc->lock, flags);
 759                 return 0;
 760         }
 761
 762         if (!tdc->busy)
 763                 goto skip_dma_stop;
 764
 765         /* Pause DMA before checking the queue status */
 766         tegra_dma_pause(tdc, true);
 767
 768         status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 769         if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
 770                 dev_dbg(tdc2dev(tdc), "%s():handling isr\n", __func__);
 771                 tdc->isr_handler(tdc, true);
 772                 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
 773         }
 774         if (tdc->tdma->chip_data->support_separate_wcount_reg)
 775                 wcount = tdc_read(tdc, TEGRA_APBDMA_CHAN_WORD_TRANSFER);
 776         else
 777                 wcount = status;
 778
 779         was_busy = tdc->busy;
 780         tegra_dma_stop(tdc);
 781
 782         if (!list_empty(&tdc->pending_sg_req) && was_busy) {
 783                 sgreq = list_first_entry(&tdc->pending_sg_req,
 784                                         typeof(*sgreq), node);
 785                 sgreq->dma_desc->bytes_transferred +=
 786                                 get_current_xferred_count(tdc, sgreq, wcount);
 787         }
 788         tegra_dma_resume(tdc);
 789
 790 skip_dma_stop:
 791         tegra_dma_abort_all(tdc);
 792
 793         while (!list_empty(&tdc->cb_desc)) {
 794                 dma_desc  = list_first_entry(&tdc->cb_desc,
 795                                         typeof(*dma_desc), cb_node);
 796                 list_del(&dma_desc->cb_node);
 797                 dma_desc->cb_count = 0;
 798         }
 799         spin_unlock_irqrestore(&tdc->lock, flags);
 800         return 0;
 801 }
 802
 803 static enum dma_status tegra_dma_tx_status(struct dma_chan *dc,
 804         dma_cookie_t cookie, struct dma_tx_state *txstate)
 805 {
 806         struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 807         struct tegra_dma_desc *dma_desc;
 808         struct tegra_dma_sg_req *sg_req;
 809         enum dma_status ret;
 810         unsigned long flags;
 811         unsigned int residual;
 812
 813         ret = dma_cookie_status(dc, cookie, txstate);
 814         if (ret == DMA_COMPLETE || !txstate)
 815                 return ret;
 816
 817         spin_lock_irqsave(&tdc->lock, flags);
 818
 819         /* Check on wait_ack desc status */
 820         list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
 821                 if (dma_desc->txd.cookie == cookie) {
 822                         residual =  dma_desc->bytes_requested -
 823                                         (dma_desc->bytes_transferred %
 824                                                 dma_desc->bytes_requested);
 825                         dma_set_residue(txstate, residual);
 826                         ret = dma_desc->dma_status;
 827                         spin_unlock_irqrestore(&tdc->lock, flags);
 828                         return ret;
 829                 }
 830         }
 831
 832         /* Check in pending list */
 833         list_for_each_entry(sg_req, &tdc->pending_sg_req, node) {
 834                 dma_desc = sg_req->dma_desc;
 835                 if (dma_desc->txd.cookie == cookie) {
 836                         residual =  dma_desc->bytes_requested -
 837                                         (dma_desc->bytes_transferred %
 838                                                 dma_desc->bytes_requested);
 839                         dma_set_residue(txstate, residual);
 840                         ret = dma_desc->dma_status;
 841                         spin_unlock_irqrestore(&tdc->lock, flags);
 842                         return ret;
 843                 }
 844         }
 845
 846         dev_dbg(tdc2dev(tdc), "cookie %d does not found\n", cookie);
 847         spin_unlock_irqrestore(&tdc->lock, flags);
 848         return ret;
 849 }
 850
 851 static inline int get_bus_width(struct tegra_dma_channel *tdc,
 852                 enum dma_slave_buswidth slave_bw)
 853 {
 854         switch (slave_bw) {
 855         case DMA_SLAVE_BUSWIDTH_1_BYTE:
 856                 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8;
 857         case DMA_SLAVE_BUSWIDTH_2_BYTES:
 858                 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16;
 859         case DMA_SLAVE_BUSWIDTH_4_BYTES:
 860                 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32;
 861         case DMA_SLAVE_BUSWIDTH_8_BYTES:
 862                 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64;
 863         default:
 864                 dev_warn(tdc2dev(tdc),
 865                         "slave bw is not supported, using 32bits\n");
 866                 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32;
 867         }
 868 }
 869
 870 static inline int get_burst_size(struct tegra_dma_channel *tdc,
 871         u32 burst_size, enum dma_slave_buswidth slave_bw, int len)
 872 {
 873         int burst_byte;
 874         int burst_ahb_width;
 875
 876         /*
 877          * burst_size from client is in terms of the bus_width.
 878          * convert them into AHB memory width which is 4 byte.
 879          */
 880         burst_byte = burst_size * slave_bw;
 881         burst_ahb_width = burst_byte / 4;
 882
 883         /* If burst size is 0 then calculate the burst size based on length */
 884         if (!burst_ahb_width) {
 885                 if (len & 0xF)
 886                         return TEGRA_APBDMA_AHBSEQ_BURST_1;
 887                 else if ((len >> 4) & 0x1)
 888                         return TEGRA_APBDMA_AHBSEQ_BURST_4;
 889                 else
 890                         return TEGRA_APBDMA_AHBSEQ_BURST_8;
 891         }
 892         if (burst_ahb_width < 4)
 893                 return TEGRA_APBDMA_AHBSEQ_BURST_1;
 894         else if (burst_ahb_width < 8)
 895                 return TEGRA_APBDMA_AHBSEQ_BURST_4;
 896         else
 897                 return TEGRA_APBDMA_AHBSEQ_BURST_8;
 898 }
 899
 900 static int get_transfer_param(struct tegra_dma_channel *tdc,
 901         enum dma_transfer_direction direction, unsigned long *apb_addr,
 902         unsigned long *apb_seq, unsigned long *csr, unsigned int *burst_size,
 903         enum dma_slave_buswidth *slave_bw)
 904 {
 905
 906         switch (direction) {
 907         case DMA_MEM_TO_DEV:
 908                 *apb_addr = tdc->dma_sconfig.dst_addr;
 909                 *apb_seq = get_bus_width(tdc, tdc->dma_sconfig.dst_addr_width);
 910                 *burst_size = tdc->dma_sconfig.dst_maxburst;
 911                 *slave_bw = tdc->dma_sconfig.dst_addr_width;
 912                 *csr = TEGRA_APBDMA_CSR_DIR;
 913                 return 0;
 914
 915         case DMA_DEV_TO_MEM:
 916                 *apb_addr = tdc->dma_sconfig.src_addr;
 917                 *apb_seq = get_bus_width(tdc, tdc->dma_sconfig.src_addr_width);
 918                 *burst_size = tdc->dma_sconfig.src_maxburst;
 919                 *slave_bw = tdc->dma_sconfig.src_addr_width;
 920                 *csr = 0;
 921                 return 0;
 922
 923         default:
 924                 dev_err(tdc2dev(tdc), "Dma direction is not supported\n");
 925                 return -EINVAL;
 926         }
 927         return -EINVAL;
 928 }
 929
 930 static void tegra_dma_prep_wcount(struct tegra_dma_channel *tdc,
 931         struct tegra_dma_channel_regs *ch_regs, u32 len)
 932 {
 933         u32 len_field = (len - 4) & 0xFFFC;
 934
 935         if (tdc->tdma->chip_data->support_separate_wcount_reg)
 936                 ch_regs->wcount = len_field;
 937         else
 938                 ch_regs->csr |= len_field;
 939 }
 940
 941 static struct dma_async_tx_descriptor *tegra_dma_prep_slave_sg(
 942         struct dma_chan *dc, struct scatterlist *sgl, unsigned int sg_len,
 943         enum dma_transfer_direction direction, unsigned long flags,
 944         void *context)
 945 {
 946         struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 947         struct tegra_dma_desc *dma_desc;
 948         unsigned int        i;
 949         struct scatterlist      *sg;
 950         unsigned long csr, ahb_seq, apb_ptr, apb_seq;
 951         struct list_head req_list;
 952         struct tegra_dma_sg_req  *sg_req = NULL;
 953         u32 burst_size;
 954         enum dma_slave_buswidth slave_bw;
 955
 956         if (!tdc->config_init) {
 957                 dev_err(tdc2dev(tdc), "dma channel is not configured\n");
 958                 return NULL;
 959         }
 960         if (sg_len < 1) {
 961                 dev_err(tdc2dev(tdc), "Invalid segment length %d\n", sg_len);
 962                 return NULL;
 963         }
 964
 965         if (get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr,
 966                                 &burst_size, &slave_bw) < 0)
 967                 return NULL;
 968
 969         INIT_LIST_HEAD(&req_list);
 970
 971         ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB;
 972         ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE <<
 973                                         TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT;
 974         ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32;
 975
 976         csr |= TEGRA_APBDMA_CSR_ONCE | TEGRA_APBDMA_CSR_FLOW;
 977         csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
 978         if (flags & DMA_PREP_INTERRUPT)
 979                 csr |= TEGRA_APBDMA_CSR_IE_EOC;
 980
 981         apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1;
 982
 983         dma_desc = tegra_dma_desc_get(tdc);
 984         if (!dma_desc) {
 985                 dev_err(tdc2dev(tdc), "Dma descriptors not available\n");
 986                 return NULL;
 987         }
 988         INIT_LIST_HEAD(&dma_desc->tx_list);
 989         INIT_LIST_HEAD(&dma_desc->cb_node);
 990         dma_desc->cb_count = 0;
 991         dma_desc->bytes_requested = 0;
 992         dma_desc->bytes_transferred = 0;
 993         dma_desc->dma_status = DMA_IN_PROGRESS;
 994
 995         /* Make transfer requests */
 996         for_each_sg(sgl, sg, sg_len, i) {
 997                 u32 len, mem;
 998
 999                 mem = sg_dma_address(sg);
1000                 len = sg_dma_len(sg);
1001
1002                 if ((len & 3) || (mem & 3) ||
1003                                 (len > tdc->tdma->chip_data->max_dma_count)) {
1004                         dev_err(tdc2dev(tdc),
1005                                 "Dma length/memory address is not supported\n");
1006                         tegra_dma_desc_put(tdc, dma_desc);
1007                         return NULL;
1008                 }
1009
1010                 sg_req = tegra_dma_sg_req_get(tdc);
1011                 if (!sg_req) {
1012                         dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
1013                         tegra_dma_desc_put(tdc, dma_desc);
1014                         return NULL;
1015                 }
1016
1017                 ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len);
1018                 dma_desc->bytes_requested += len;
1019
1020                 sg_req->ch_regs.apb_ptr = apb_ptr;
1021                 sg_req->ch_regs.ahb_ptr = mem;
1022                 sg_req->ch_regs.csr = csr;
1023                 tegra_dma_prep_wcount(tdc, &sg_req->ch_regs, len);
1024                 sg_req->ch_regs.apb_seq = apb_seq;
1025                 sg_req->ch_regs.ahb_seq = ahb_seq;
1026                 sg_req->configured = false;
1027                 sg_req->last_sg = false;
1028                 sg_req->dma_desc = dma_desc;
1029                 sg_req->req_len = len;
1030
1031                 list_add_tail(&sg_req->node, &dma_desc->tx_list);
1032         }
1033         sg_req->last_sg = true;
1034         if (flags & DMA_CTRL_ACK)
1035                 dma_desc->txd.flags = DMA_CTRL_ACK;
1036
1037         /*
1038          * Make sure that mode should not be conflicting with currently
1039          * configured mode.
1040          */
1041         if (!tdc->isr_handler) {
1042                 tdc->isr_handler = handle_once_dma_done;
1043                 tdc->cyclic = false;
1044         } else {
1045                 if (tdc->cyclic) {
1046                         dev_err(tdc2dev(tdc), "DMA configured in cyclic mode\n");
1047                         tegra_dma_desc_put(tdc, dma_desc);
1048                         return NULL;
1049                 }
1050         }
1051
1052         return &dma_desc->txd;
1053 }
1054
1055 static struct dma_async_tx_descriptor *tegra_dma_prep_dma_cyclic(
1056         struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len,
1057         size_t period_len, enum dma_transfer_direction direction,
1058         unsigned long flags)
1059 {
1060         struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1061         struct tegra_dma_desc *dma_desc = NULL;
1062         struct tegra_dma_sg_req  *sg_req = NULL;
1063         unsigned long csr, ahb_seq, apb_ptr, apb_seq;
1064         int len;
1065         size_t remain_len;
1066         dma_addr_t mem = buf_addr;
1067         u32 burst_size;
1068         enum dma_slave_buswidth slave_bw;
1069
1070         if (!buf_len || !period_len) {
1071                 dev_err(tdc2dev(tdc), "Invalid buffer/period len\n");
1072                 return NULL;
1073         }
1074
1075         if (!tdc->config_init) {
1076                 dev_err(tdc2dev(tdc), "DMA slave is not configured\n");
1077                 return NULL;
1078         }
1079
1080         /*
1081          * We allow to take more number of requests till DMA is
1082          * not started. The driver will loop over all requests.
1083          * Once DMA is started then new requests can be queued only after
1084          * terminating the DMA.
1085          */
1086         if (tdc->busy) {
1087                 dev_err(tdc2dev(tdc), "Request not allowed when dma running\n");
1088                 return NULL;
1089         }
1090
1091         /*
1092          * We only support cycle transfer when buf_len is multiple of
1093          * period_len.
1094          */
1095         if (buf_len % period_len) {
1096                 dev_err(tdc2dev(tdc), "buf_len is not multiple of period_len\n");
1097                 return NULL;
1098         }
1099
1100         len = period_len;
1101         if ((len & 3) || (buf_addr & 3) ||
1102                         (len > tdc->tdma->chip_data->max_dma_count)) {
1103                 dev_err(tdc2dev(tdc), "Req len/mem address is not correct\n");
1104                 return NULL;
1105         }
1106
1107         if (get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr,
1108                                 &burst_size, &slave_bw) < 0)
1109                 return NULL;
1110
1111         ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB;
1112         ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE <<
1113                                         TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT;
1114         ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32;
1115
1116         csr |= TEGRA_APBDMA_CSR_FLOW;
1117         if (flags & DMA_PREP_INTERRUPT)
1118                 csr |= TEGRA_APBDMA_CSR_IE_EOC;
1119         csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
1120
1121         apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1;
1122
1123         dma_desc = tegra_dma_desc_get(tdc);
1124         if (!dma_desc) {
1125                 dev_err(tdc2dev(tdc), "not enough descriptors available\n");
1126                 return NULL;
1127         }
1128
1129         INIT_LIST_HEAD(&dma_desc->tx_list);
1130         INIT_LIST_HEAD(&dma_desc->cb_node);
1131         dma_desc->cb_count = 0;
1132
1133         dma_desc->bytes_transferred = 0;
1134         dma_desc->bytes_requested = buf_len;
1135         remain_len = buf_len;
1136
1137         /* Split transfer equal to period size */
1138         while (remain_len) {
1139                 sg_req = tegra_dma_sg_req_get(tdc);
1140                 if (!sg_req) {
1141                         dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
1142                         tegra_dma_desc_put(tdc, dma_desc);
1143                         return NULL;
1144                 }
1145
1146                 ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len);
1147                 sg_req->ch_regs.apb_ptr = apb_ptr;
1148                 sg_req->ch_regs.ahb_ptr = mem;
1149                 sg_req->ch_regs.csr = csr;
1150                 tegra_dma_prep_wcount(tdc, &sg_req->ch_regs, len);
1151                 sg_req->ch_regs.apb_seq = apb_seq;
1152                 sg_req->ch_regs.ahb_seq = ahb_seq;
1153                 sg_req->configured = false;
1154                 sg_req->last_sg = false;
1155                 sg_req->dma_desc = dma_desc;
1156                 sg_req->req_len = len;
1157
1158                 list_add_tail(&sg_req->node, &dma_desc->tx_list);
1159                 remain_len -= len;
1160                 mem += len;
1161         }
1162         sg_req->last_sg = true;
1163         if (flags & DMA_CTRL_ACK)
1164                 dma_desc->txd.flags = DMA_CTRL_ACK;
1165
1166         /*
1167          * Make sure that mode should not be conflicting with currently
1168          * configured mode.
1169          */
1170         if (!tdc->isr_handler) {
1171                 tdc->isr_handler = handle_cont_sngl_cycle_dma_done;
1172                 tdc->cyclic = true;
1173         } else {
1174                 if (!tdc->cyclic) {
1175                         dev_err(tdc2dev(tdc), "DMA configuration conflict\n");
1176                         tegra_dma_desc_put(tdc, dma_desc);
1177                         return NULL;
1178                 }
1179         }
1180
1181         return &dma_desc->txd;
1182 }
1183
1184 static int tegra_dma_alloc_chan_resources(struct dma_chan *dc)
1185 {
1186         struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1187         struct tegra_dma *tdma = tdc->tdma;
1188         int ret;
1189
1190         dma_cookie_init(&tdc->dma_chan);
1191         tdc->config_init = false;
1192
1193         ret = pm_runtime_get_sync(tdma->dev);
1194         if (ret < 0)
1195                 return ret;
1196
1197         return 0;
1198 }
1199
1200 static void tegra_dma_free_chan_resources(struct dma_chan *dc)
1201 {
1202         struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1203         struct tegra_dma *tdma = tdc->tdma;
1204
1205         struct tegra_dma_desc *dma_desc;
1206         struct tegra_dma_sg_req *sg_req;
1207         struct list_head dma_desc_list;
1208         struct list_head sg_req_list;
1209         unsigned long flags;
1210
1211         INIT_LIST_HEAD(&dma_desc_list);
1212         INIT_LIST_HEAD(&sg_req_list);
1213
1214         dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id);
1215
1216         if (tdc->busy)
1217                 tegra_dma_terminate_all(dc);
1218
1219         spin_lock_irqsave(&tdc->lock, flags);
1220         list_splice_init(&tdc->pending_sg_req, &sg_req_list);
1221         list_splice_init(&tdc->free_sg_req, &sg_req_list);
1222         list_splice_init(&tdc->free_dma_desc, &dma_desc_list);
1223         INIT_LIST_HEAD(&tdc->cb_desc);
1224         tdc->config_init = false;
1225         tdc->isr_handler = NULL;
1226         spin_unlock_irqrestore(&tdc->lock, flags);
1227
1228         while (!list_empty(&dma_desc_list)) {
1229                 dma_desc = list_first_entry(&dma_desc_list,
1230                                         typeof(*dma_desc), node);
1231                 list_del(&dma_desc->node);
1232                 kfree(dma_desc);
1233         }
1234
1235         while (!list_empty(&sg_req_list)) {
1236                 sg_req = list_first_entry(&sg_req_list, typeof(*sg_req), node);
1237                 list_del(&sg_req->node);
1238                 kfree(sg_req);
1239         }
1240         pm_runtime_put(tdma->dev);
1241
1242         tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID;
1243 }
1244
1245 static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
1246                                            struct of_dma *ofdma)
1247 {
1248         struct tegra_dma *tdma = ofdma->of_dma_data;
1249         struct dma_chan *chan;
1250         struct tegra_dma_channel *tdc;
1251
1252         if (dma_spec->args[0] > TEGRA_APBDMA_CSR_REQ_SEL_MASK) {
1253                 dev_err(tdma->dev, "Invalid slave id: %d\n", dma_spec->args[0]);
1254                 return NULL;
1255         }
1256
1257         chan = dma_get_any_slave_channel(&tdma->dma_dev);
1258         if (!chan)
1259                 return NULL;
1260
1261         tdc = to_tegra_dma_chan(chan);
1262         tdc->slave_id = dma_spec->args[0];
1263
1264         return chan;
1265 }
1266
1267 /* Tegra20 specific DMA controller information */
1268 static const struct tegra_dma_chip_data tegra20_dma_chip_data = {
1269         .nr_channels            = 16,
1270         .channel_reg_size       = 0x20,
1271         .max_dma_count          = 1024UL * 64,
1272         .support_channel_pause  = false,
1273         .support_separate_wcount_reg = false,
1274 };
1275
1276 /* Tegra30 specific DMA controller information */
1277 static const struct tegra_dma_chip_data tegra30_dma_chip_data = {
1278         .nr_channels            = 32,
1279         .channel_reg_size       = 0x20,
1280         .max_dma_count          = 1024UL * 64,
1281         .support_channel_pause  = false,
1282         .support_separate_wcount_reg = false,
1283 };
1284
1285 /* Tegra114 specific DMA controller information */
1286 static const struct tegra_dma_chip_data tegra114_dma_chip_data = {
1287         .nr_channels            = 32,
1288         .channel_reg_size       = 0x20,
1289         .max_dma_count          = 1024UL * 64,
1290         .support_channel_pause  = true,
1291         .support_separate_wcount_reg = false,
1292 };
1293
1294 /* Tegra148 specific DMA controller information */
1295 static const struct tegra_dma_chip_data tegra148_dma_chip_data = {
1296         .nr_channels            = 32,
1297         .channel_reg_size       = 0x40,
1298         .max_dma_count          = 1024UL * 64,
1299         .support_channel_pause  = true,
1300         .support_separate_wcount_reg = true,
1301 };
1302
1303 static int tegra_dma_probe(struct platform_device *pdev)
1304 {
1305         struct resource *res;
1306         struct tegra_dma *tdma;
1307         int ret;
1308         int i;
1309         const struct tegra_dma_chip_data *cdata;
1310
1311         cdata = of_device_get_match_data(&pdev->dev);
1312         if (!cdata) {
1313                 dev_err(&pdev->dev, "Error: No device match data found\n");
1314                 return -ENODEV;
1315         }
1316
1317         tdma = devm_kzalloc(&pdev->dev, sizeof(*tdma) + cdata->nr_channels *
1318                         sizeof(struct tegra_dma_channel), GFP_KERNEL);
1319         if (!tdma)
1320                 return -ENOMEM;
1321
1322         tdma->dev = &pdev->dev;
1323         tdma->chip_data = cdata;
1324         platform_set_drvdata(pdev, tdma);
1325
1326         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1327         tdma->base_addr = devm_ioremap_resource(&pdev->dev, res);
1328         if (IS_ERR(tdma->base_addr))
1329                 return PTR_ERR(tdma->base_addr);
1330
1331         tdma->dma_clk = devm_clk_get(&pdev->dev, NULL);
1332         if (IS_ERR(tdma->dma_clk)) {
1333                 dev_err(&pdev->dev, "Error: Missing controller clock\n");
1334                 return PTR_ERR(tdma->dma_clk);
1335         }
1336
1337         tdma->rst = devm_reset_control_get(&pdev->dev, "dma");
1338         if (IS_ERR(tdma->rst)) {
1339                 dev_err(&pdev->dev, "Error: Missing reset\n");
1340                 return PTR_ERR(tdma->rst);
1341         }
1342
1343         spin_lock_init(&tdma->global_lock);
1344
1345         pm_runtime_enable(&pdev->dev);
1346         if (!pm_runtime_enabled(&pdev->dev))
1347                 ret = tegra_dma_runtime_resume(&pdev->dev);
1348         else
1349                 ret = pm_runtime_get_sync(&pdev->dev);
1350
1351         if (ret < 0) {
1352                 pm_runtime_disable(&pdev->dev);
1353                 return ret;
1354         }
1355
1356         /* Reset DMA controller */
1357         reset_control_assert(tdma->rst);
1358         udelay(2);
1359         reset_control_deassert(tdma->rst);
1360
1361         /* Enable global DMA registers */
1362         tdma_write(tdma, TEGRA_APBDMA_GENERAL, TEGRA_APBDMA_GENERAL_ENABLE);
1363         tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0);
1364         tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul);
1365
1366         pm_runtime_put(&pdev->dev);
1367
1368         INIT_LIST_HEAD(&tdma->dma_dev.channels);
1369         for (i = 0; i < cdata->nr_channels; i++) {
1370                 struct tegra_dma_channel *tdc = &tdma->channels[i];
1371
1372                 tdc->chan_addr = tdma->base_addr +
1373                                  TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET +
1374                                  (i * cdata->channel_reg_size);
1375
1376                 res = platform_get_resource(pdev, IORESOURCE_IRQ, i);
1377                 if (!res) {
1378                         ret = -EINVAL;
1379                         dev_err(&pdev->dev, "No irq resource for chan %d\n", i);
1380                         goto err_irq;
1381                 }
1382                 tdc->irq = res->start;
1383                 snprintf(tdc->name, sizeof(tdc->name), "apbdma.%d", i);
1384                 ret = request_irq(tdc->irq, tegra_dma_isr, 0, tdc->name, tdc);
1385                 if (ret) {
1386                         dev_err(&pdev->dev,
1387                                 "request_irq failed with err %d channel %d\n",
1388                                 ret, i);
1389                         goto err_irq;
1390                 }
1391
1392                 tdc->dma_chan.device = &tdma->dma_dev;
1393                 dma_cookie_init(&tdc->dma_chan);
1394                 list_add_tail(&tdc->dma_chan.device_node,
1395                                 &tdma->dma_dev.channels);
1396                 tdc->tdma = tdma;
1397                 tdc->id = i;
1398                 tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID;
1399
1400                 tasklet_init(&tdc->tasklet, tegra_dma_tasklet,
1401                                 (unsigned long)tdc);
1402                 spin_lock_init(&tdc->lock);
1403
1404                 INIT_LIST_HEAD(&tdc->pending_sg_req);
1405                 INIT_LIST_HEAD(&tdc->free_sg_req);
1406                 INIT_LIST_HEAD(&tdc->free_dma_desc);
1407                 INIT_LIST_HEAD(&tdc->cb_desc);
1408         }
1409
1410         dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask);
1411         dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask);
1412         dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask);
1413
1414         tdma->global_pause_count = 0;
1415         tdma->dma_dev.dev = &pdev->dev;
1416         tdma->dma_dev.device_alloc_chan_resources =
1417                                         tegra_dma_alloc_chan_resources;
1418         tdma->dma_dev.device_free_chan_resources =
1419                                         tegra_dma_free_chan_resources;
1420         tdma->dma_dev.device_prep_slave_sg = tegra_dma_prep_slave_sg;
1421         tdma->dma_dev.device_prep_dma_cyclic = tegra_dma_prep_dma_cyclic;
1422         tdma->dma_dev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1423                 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1424                 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1425                 BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
1426         tdma->dma_dev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1427                 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1428                 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1429                 BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
1430         tdma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1431         /*
1432          * XXX The hardware appears to support
1433          * DMA_RESIDUE_GRANULARITY_BURST-level reporting, but it's
1434          * only used by this driver during tegra_dma_terminate_all()
1435          */
1436         tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
1437         tdma->dma_dev.device_config = tegra_dma_slave_config;
1438         tdma->dma_dev.device_terminate_all = tegra_dma_terminate_all;
1439         tdma->dma_dev.device_tx_status = tegra_dma_tx_status;
1440         tdma->dma_dev.device_issue_pending = tegra_dma_issue_pending;
1441
1442         ret = dma_async_device_register(&tdma->dma_dev);
1443         if (ret < 0) {
1444                 dev_err(&pdev->dev,
1445                         "Tegra20 APB DMA driver registration failed %d\n", ret);
1446                 goto err_irq;
1447         }
1448
1449         ret = of_dma_controller_register(pdev->dev.of_node,
1450                                          tegra_dma_of_xlate, tdma);
1451         if (ret < 0) {
1452                 dev_err(&pdev->dev,
1453                         "Tegra20 APB DMA OF registration failed %d\n", ret);
1454                 goto err_unregister_dma_dev;
1455         }
1456
1457         dev_info(&pdev->dev, "Tegra20 APB DMA driver register %d channels\n",
1458                         cdata->nr_channels);
1459         return 0;
1460
1461 err_unregister_dma_dev:
1462         dma_async_device_unregister(&tdma->dma_dev);
1463 err_irq:
1464         while (--i >= 0) {
1465                 struct tegra_dma_channel *tdc = &tdma->channels[i];
1466
1467                 free_irq(tdc->irq, tdc);
1468                 tasklet_kill(&tdc->tasklet);
1469         }
1470
1471         pm_runtime_disable(&pdev->dev);
1472         if (!pm_runtime_status_suspended(&pdev->dev))
1473                 tegra_dma_runtime_suspend(&pdev->dev);
1474         return ret;
1475 }
1476
1477 static int tegra_dma_remove(struct platform_device *pdev)
1478 {
1479         struct tegra_dma *tdma = platform_get_drvdata(pdev);
1480         int i;
1481         struct tegra_dma_channel *tdc;
1482
1483         dma_async_device_unregister(&tdma->dma_dev);
1484
1485         for (i = 0; i < tdma->chip_data->nr_channels; ++i) {
1486                 tdc = &tdma->channels[i];
1487                 free_irq(tdc->irq, tdc);
1488                 tasklet_kill(&tdc->tasklet);
1489         }
1490
1491         pm_runtime_disable(&pdev->dev);
1492         if (!pm_runtime_status_suspended(&pdev->dev))
1493                 tegra_dma_runtime_suspend(&pdev->dev);
1494
1495         return 0;
1496 }
1497
1498 static int tegra_dma_runtime_suspend(struct device *dev)
1499 {
1500         struct tegra_dma *tdma = dev_get_drvdata(dev);
1501
1502         clk_disable_unprepare(tdma->dma_clk);
1503         return 0;
1504 }
1505
1506 static int tegra_dma_runtime_resume(struct device *dev)
1507 {
1508         struct tegra_dma *tdma = dev_get_drvdata(dev);
1509         int ret;
1510
1511         ret = clk_prepare_enable(tdma->dma_clk);
1512         if (ret < 0) {
1513                 dev_err(dev, "clk_enable failed: %d\n", ret);
1514                 return ret;
1515         }
1516         return 0;
1517 }
1518
1519 #ifdef CONFIG_PM_SLEEP
1520 static int tegra_dma_pm_suspend(struct device *dev)
1521 {
1522         struct tegra_dma *tdma = dev_get_drvdata(dev);
1523         int i;
1524         int ret;
1525
1526         /* Enable clock before accessing register */
1527         ret = pm_runtime_get_sync(dev);
1528         if (ret < 0)
1529                 return ret;
1530
1531         tdma->reg_gen = tdma_read(tdma, TEGRA_APBDMA_GENERAL);
1532         for (i = 0; i < tdma->chip_data->nr_channels; i++) {
1533                 struct tegra_dma_channel *tdc = &tdma->channels[i];
1534                 struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg;
1535
1536                 /* Only save the state of DMA channels that are in use */
1537                 if (!tdc->config_init)
1538                         continue;
1539
1540                 ch_reg->csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR);
1541                 ch_reg->ahb_ptr = tdc_read(tdc, TEGRA_APBDMA_CHAN_AHBPTR);
1542                 ch_reg->apb_ptr = tdc_read(tdc, TEGRA_APBDMA_CHAN_APBPTR);
1543                 ch_reg->ahb_seq = tdc_read(tdc, TEGRA_APBDMA_CHAN_AHBSEQ);
1544                 ch_reg->apb_seq = tdc_read(tdc, TEGRA_APBDMA_CHAN_APBSEQ);
1545                 if (tdma->chip_data->support_separate_wcount_reg)
1546                         ch_reg->wcount = tdc_read(tdc,
1547                                                   TEGRA_APBDMA_CHAN_WCOUNT);
1548         }
1549
1550         /* Disable clock */
1551         pm_runtime_put(dev);
1552         return 0;
1553 }
1554
1555 static int tegra_dma_pm_resume(struct device *dev)
1556 {
1557         struct tegra_dma *tdma = dev_get_drvdata(dev);
1558         int i;
1559         int ret;
1560
1561         /* Enable clock before accessing register */
1562         ret = pm_runtime_get_sync(dev);
1563         if (ret < 0)
1564                 return ret;
1565
1566         tdma_write(tdma, TEGRA_APBDMA_GENERAL, tdma->reg_gen);
1567         tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0);
1568         tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul);
1569
1570         for (i = 0; i < tdma->chip_data->nr_channels; i++) {
1571                 struct tegra_dma_channel *tdc = &tdma->channels[i];
1572                 struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg;
1573
1574                 /* Only restore the state of DMA channels that are in use */
1575                 if (!tdc->config_init)
1576                         continue;
1577
1578                 if (tdma->chip_data->support_separate_wcount_reg)
1579                         tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT,
1580                                   ch_reg->wcount);
1581                 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_reg->apb_seq);
1582                 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_reg->apb_ptr);
1583                 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_reg->ahb_seq);
1584                 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_reg->ahb_ptr);
1585                 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
1586                         (ch_reg->csr & ~TEGRA_APBDMA_CSR_ENB));
1587         }
1588
1589         /* Disable clock */
1590         pm_runtime_put(dev);
1591         return 0;
1592 }
1593 #endif
1594
1595 static const struct dev_pm_ops tegra_dma_dev_pm_ops = {
1596         SET_RUNTIME_PM_OPS(tegra_dma_runtime_suspend, tegra_dma_runtime_resume,
1597                            NULL)
1598         SET_SYSTEM_SLEEP_PM_OPS(tegra_dma_pm_suspend, tegra_dma_pm_resume)
1599 };
1600
1601 static const struct of_device_id tegra_dma_of_match[] = {
1602         {
1603                 .compatible = "nvidia,tegra148-apbdma",
1604                 .data = &tegra148_dma_chip_data,
1605         }, {
1606                 .compatible = "nvidia,tegra114-apbdma",
1607                 .data = &tegra114_dma_chip_data,
1608         }, {
1609                 .compatible = "nvidia,tegra30-apbdma",
1610                 .data = &tegra30_dma_chip_data,
1611         }, {
1612                 .compatible = "nvidia,tegra20-apbdma",
1613                 .data = &tegra20_dma_chip_data,
1614         }, {
1615         },
1616 };
1617 MODULE_DEVICE_TABLE(of, tegra_dma_of_match);
1618
1619 static struct platform_driver tegra_dmac_driver = {
1620         .driver = {
1621                 .name   = "tegra-apbdma",
1622                 .pm     = &tegra_dma_dev_pm_ops,
1623                 .of_match_table = tegra_dma_of_match,
1624         },
1625         .probe          = tegra_dma_probe,
1626         .remove         = tegra_dma_remove,
1627 };
1628
1629 module_platform_driver(tegra_dmac_driver);
1630
1631 MODULE_ALIAS("platform:tegra20-apbdma");
1632 MODULE_DESCRIPTION("NVIDIA Tegra APB DMA Controller driver");
1633 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
1634 MODULE_LICENSE("GPL v2");