drivers/dma/bcm6348-iudma.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2018 Álvaro Fernández Rojas <[email protected]>
   4  *
   5  * Derived from linux/drivers/dma/bcm63xx-iudma.c:
   6  *      Copyright (C) 2015 Simon Arlott <[email protected]>
   7  *
   8  * Derived from linux/drivers/net/ethernet/broadcom/bcm63xx_enet.c:
   9  *      Copyright (C) 2008 Maxime Bizon <[email protected]>
  10  *
  11  * Derived from bcm963xx_4.12L.06B_consumer/shared/opensource/include/bcm963xx/63268_map_part.h:
  12  *      Copyright (C) 2000-2010 Broadcom Corporation
  13  *
  14  * Derived from bcm963xx_4.12L.06B_consumer/bcmdrivers/opensource/net/enet/impl4/bcmenet.c:
  15  *      Copyright (C) 2010 Broadcom Corporation
  16  */
  17
  18 #include <clk.h>
  19 #include <cpu_func.h>
  20 #include <dm.h>
  21 #include <dma-uclass.h>
  22 #include <log.h>
  23 #include <malloc.h>
  24 #include <memalign.h>
  25 #include <net.h>
  26 #include <reset.h>
  27 #include <asm/io.h>
  28 #include <linux/bitops.h>
  29 #include <linux/delay.h>
  30 #include <linux/printk.h>
  31
  32 #define DMA_RX_DESC     6
  33 #define DMA_TX_DESC     1
  34
  35 /* DMA Channels */
  36 #define DMA_CHAN_FLOWC(x)               ((x) >> 1)
  37 #define DMA_CHAN_MAX                    16
  38 #define DMA_CHAN_SIZE                   0x10
  39 #define DMA_CHAN_TOUT                   500
  40
  41 /* DMA Global Configuration register */
  42 #define DMA_CFG_REG                     0x00
  43 #define  DMA_CFG_ENABLE_SHIFT           0
  44 #define  DMA_CFG_ENABLE_MASK            (1 << DMA_CFG_ENABLE_SHIFT)
  45 #define  DMA_CFG_FLOWC_ENABLE(x)        BIT(DMA_CHAN_FLOWC(x) + 1)
  46 #define  DMA_CFG_NCHANS_SHIFT           24
  47 #define  DMA_CFG_NCHANS_MASK            (0xf << DMA_CFG_NCHANS_SHIFT)
  48
  49 /* DMA Global Flow Control registers */
  50 #define DMA_FLOWC_THR_LO_REG(x)         (0x04 + DMA_CHAN_FLOWC(x) * 0x0c)
  51 #define DMA_FLOWC_THR_HI_REG(x)         (0x08 + DMA_CHAN_FLOWC(x) * 0x0c)
  52 #define DMA_FLOWC_ALLOC_REG(x)          (0x0c + DMA_CHAN_FLOWC(x) * 0x0c)
  53 #define  DMA_FLOWC_ALLOC_FORCE_SHIFT    31
  54 #define  DMA_FLOWC_ALLOC_FORCE_MASK     (1 << DMA_FLOWC_ALLOC_FORCE_SHIFT)
  55
  56 /* DMA Global Reset register */
  57 #define DMA_RST_REG                     0x34
  58 #define  DMA_RST_CHAN_SHIFT             0
  59 #define  DMA_RST_CHAN_MASK(x)           (1 << x)
  60
  61 /* DMA Channel Configuration register */
  62 #define DMAC_CFG_REG(x)                 (DMA_CHAN_SIZE * (x) + 0x00)
  63 #define  DMAC_CFG_ENABLE_SHIFT          0
  64 #define  DMAC_CFG_ENABLE_MASK           (1 << DMAC_CFG_ENABLE_SHIFT)
  65 #define  DMAC_CFG_PKT_HALT_SHIFT        1
  66 #define  DMAC_CFG_PKT_HALT_MASK         (1 << DMAC_CFG_PKT_HALT_SHIFT)
  67 #define  DMAC_CFG_BRST_HALT_SHIFT       2
  68 #define  DMAC_CFG_BRST_HALT_MASK        (1 << DMAC_CFG_BRST_HALT_SHIFT)
  69
  70 /* DMA Channel Max Burst Length register */
  71 #define DMAC_BURST_REG(x)               (DMA_CHAN_SIZE * (x) + 0x0c)
  72
  73 /* DMA SRAM Descriptor Ring Start register */
  74 #define DMAS_RSTART_REG(x)              (DMA_CHAN_SIZE * (x) + 0x00)
  75
  76 /* DMA SRAM State/Bytes done/ring offset register */
  77 #define DMAS_STATE_DATA_REG(x)          (DMA_CHAN_SIZE * (x) + 0x04)
  78
  79 /* DMA SRAM Buffer Descriptor status and length register */
  80 #define DMAS_DESC_LEN_STATUS_REG(x)     (DMA_CHAN_SIZE * (x) + 0x08)
  81
  82 /* DMA SRAM Buffer Descriptor status and length register */
  83 #define DMAS_DESC_BASE_BUFPTR_REG(x)    (DMA_CHAN_SIZE * (x) + 0x0c)
  84
  85 /* DMA Descriptor Status */
  86 #define DMAD_ST_CRC_SHIFT               8
  87 #define DMAD_ST_CRC_MASK                (1 << DMAD_ST_CRC_SHIFT)
  88 #define DMAD_ST_WRAP_SHIFT              12
  89 #define DMAD_ST_WRAP_MASK               (1 << DMAD_ST_WRAP_SHIFT)
  90 #define DMAD_ST_SOP_SHIFT               13
  91 #define DMAD_ST_SOP_MASK                (1 << DMAD_ST_SOP_SHIFT)
  92 #define DMAD_ST_EOP_SHIFT               14
  93 #define DMAD_ST_EOP_MASK                (1 << DMAD_ST_EOP_SHIFT)
  94 #define DMAD_ST_OWN_SHIFT               15
  95 #define DMAD_ST_OWN_MASK                (1 << DMAD_ST_OWN_SHIFT)
  96
  97 #define DMAD6348_ST_OV_ERR_SHIFT        0
  98 #define DMAD6348_ST_OV_ERR_MASK         (1 << DMAD6348_ST_OV_ERR_SHIFT)
  99 #define DMAD6348_ST_CRC_ERR_SHIFT       1
 100 #define DMAD6348_ST_CRC_ERR_MASK        (1 << DMAD6348_ST_CRC_ERR_SHIFT)
 101 #define DMAD6348_ST_RX_ERR_SHIFT        2
 102 #define DMAD6348_ST_RX_ERR_MASK         (1 << DMAD6348_ST_RX_ERR_SHIFT)
 103 #define DMAD6348_ST_OS_ERR_SHIFT        4
 104 #define DMAD6348_ST_OS_ERR_MASK         (1 << DMAD6348_ST_OS_ERR_SHIFT)
 105 #define DMAD6348_ST_UN_ERR_SHIFT        9
 106 #define DMAD6348_ST_UN_ERR_MASK         (1 << DMAD6348_ST_UN_ERR_SHIFT)
 107
 108 struct bcm6348_dma_desc {
 109         uint16_t length;
 110         uint16_t status;
 111         uint32_t address;
 112 };
 113
 114 struct bcm6348_chan_priv {
 115         void __iomem *dma_ring;
 116         uint8_t dma_ring_size;
 117         uint8_t desc_id;
 118         uint8_t desc_cnt;
 119         bool *busy_desc;
 120         bool running;
 121 };
 122
 123 struct bcm6348_iudma_hw {
 124         uint16_t err_mask;
 125 };
 126
 127 struct bcm6348_iudma_priv {
 128         const struct bcm6348_iudma_hw *hw;
 129         void __iomem *base;
 130         void __iomem *chan;
 131         void __iomem *sram;
 132         struct bcm6348_chan_priv **ch_priv;
 133         uint8_t n_channels;
 134 };
 135
 136 static inline bool bcm6348_iudma_chan_is_rx(uint8_t ch)
 137 {
 138         return !(ch & 1);
 139 }
 140
 141 static inline void bcm6348_iudma_fdc(void *ptr, ulong size)
 142 {
 143         ulong start = (ulong) ptr;
 144
 145         flush_dcache_range(start, start + size);
 146 }
 147
 148 static inline void bcm6348_iudma_idc(void *ptr, ulong size)
 149 {
 150         ulong start = (ulong) ptr;
 151
 152         invalidate_dcache_range(start, start + size);
 153 }
 154
 155 static void bcm6348_iudma_chan_stop(struct bcm6348_iudma_priv *priv,
 156                                     uint8_t ch)
 157 {
 158         unsigned int timeout = DMA_CHAN_TOUT;
 159
 160         do {
 161                 uint32_t cfg, halt;
 162
 163                 if (timeout > DMA_CHAN_TOUT / 2)
 164                         halt = DMAC_CFG_PKT_HALT_MASK;
 165                 else
 166                         halt = DMAC_CFG_BRST_HALT_MASK;
 167
 168                 /* try to stop dma channel */
 169                 writel_be(halt, priv->chan + DMAC_CFG_REG(ch));
 170                 mb();
 171
 172                 /* check if channel was stopped */
 173                 cfg = readl_be(priv->chan + DMAC_CFG_REG(ch));
 174                 if (!(cfg & DMAC_CFG_ENABLE_MASK))
 175                         break;
 176
 177                 udelay(1);
 178         } while (--timeout);
 179
 180         if (!timeout)
 181                 pr_err("unable to stop channel %u\n", ch);
 182
 183         /* reset dma channel */
 184         setbits_be32(priv->base + DMA_RST_REG, DMA_RST_CHAN_MASK(ch));
 185         mb();
 186         clrbits_be32(priv->base + DMA_RST_REG, DMA_RST_CHAN_MASK(ch));
 187 }
 188
 189 static int bcm6348_iudma_disable(struct dma *dma)
 190 {
 191         struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
 192         struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
 193
 194         /* stop dma channel */
 195         bcm6348_iudma_chan_stop(priv, dma->id);
 196
 197         /* dma flow control */
 198         if (bcm6348_iudma_chan_is_rx(dma->id))
 199                 writel_be(DMA_FLOWC_ALLOC_FORCE_MASK,
 200                           DMA_FLOWC_ALLOC_REG(dma->id));
 201
 202         /* init channel config */
 203         ch_priv->running = false;
 204         ch_priv->desc_id = 0;
 205         if (bcm6348_iudma_chan_is_rx(dma->id))
 206                 ch_priv->desc_cnt = 0;
 207         else
 208                 ch_priv->desc_cnt = ch_priv->dma_ring_size;
 209
 210         return 0;
 211 }
 212
 213 static int bcm6348_iudma_enable(struct dma *dma)
 214 {
 215         const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
 216         struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
 217         struct bcm6348_dma_desc *dma_desc = ch_priv->dma_ring;
 218         uint8_t i;
 219
 220         /* dma ring init */
 221         for (i = 0; i < ch_priv->desc_cnt; i++) {
 222                 if (bcm6348_iudma_chan_is_rx(dma->id)) {
 223                         ch_priv->busy_desc[i] = false;
 224                         dma_desc->status |= DMAD_ST_OWN_MASK;
 225                 } else {
 226                         dma_desc->status = 0;
 227                         dma_desc->length = 0;
 228                         dma_desc->address = 0;
 229                 }
 230
 231                 if (i == ch_priv->desc_cnt - 1)
 232                         dma_desc->status |= DMAD_ST_WRAP_MASK;
 233
 234                 dma_desc++;
 235         }
 236
 237         /* init to first descriptor */
 238         ch_priv->desc_id = 0;
 239
 240         /* force cache writeback */
 241         bcm6348_iudma_fdc(ch_priv->dma_ring,
 242                           sizeof(*dma_desc) * ch_priv->desc_cnt);
 243
 244         /* clear sram */
 245         writel_be(0, priv->sram + DMAS_STATE_DATA_REG(dma->id));
 246         writel_be(0, priv->sram + DMAS_DESC_LEN_STATUS_REG(dma->id));
 247         writel_be(0, priv->sram + DMAS_DESC_BASE_BUFPTR_REG(dma->id));
 248
 249         /* set dma ring start */
 250         writel_be(virt_to_phys(ch_priv->dma_ring),
 251                   priv->sram + DMAS_RSTART_REG(dma->id));
 252
 253         /* set flow control */
 254         if (bcm6348_iudma_chan_is_rx(dma->id)) {
 255                 u32 val;
 256
 257                 setbits_be32(priv->base + DMA_CFG_REG,
 258                              DMA_CFG_FLOWC_ENABLE(dma->id));
 259
 260                 val = ch_priv->desc_cnt / 3;
 261                 writel_be(val, priv->base + DMA_FLOWC_THR_LO_REG(dma->id));
 262
 263                 val = (ch_priv->desc_cnt * 2) / 3;
 264                 writel_be(val, priv->base + DMA_FLOWC_THR_HI_REG(dma->id));
 265
 266                 writel_be(0, priv->base + DMA_FLOWC_ALLOC_REG(dma->id));
 267         }
 268
 269         /* set dma max burst */
 270         writel_be(ch_priv->desc_cnt,
 271                   priv->chan + DMAC_BURST_REG(dma->id));
 272
 273         /* kick rx dma channel */
 274         if (bcm6348_iudma_chan_is_rx(dma->id))
 275                 setbits_be32(priv->chan + DMAC_CFG_REG(dma->id),
 276                              DMAC_CFG_ENABLE_MASK);
 277
 278         /* channel is now enabled */
 279         ch_priv->running = true;
 280
 281         return 0;
 282 }
 283
 284 static int bcm6348_iudma_request(struct dma *dma)
 285 {
 286         const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
 287         struct bcm6348_chan_priv *ch_priv;
 288
 289         /* check if channel is valid */
 290         if (dma->id >= priv->n_channels)
 291                 return -ENODEV;
 292
 293         /* alloc channel private data */
 294         priv->ch_priv[dma->id] = calloc(1, sizeof(struct bcm6348_chan_priv));
 295         if (!priv->ch_priv[dma->id])
 296                 return -ENOMEM;
 297         ch_priv = priv->ch_priv[dma->id];
 298
 299         /* alloc dma ring */
 300         if (bcm6348_iudma_chan_is_rx(dma->id))
 301                 ch_priv->dma_ring_size = DMA_RX_DESC;
 302         else
 303                 ch_priv->dma_ring_size = DMA_TX_DESC;
 304
 305         ch_priv->dma_ring =
 306                 malloc_cache_aligned(sizeof(struct bcm6348_dma_desc) *
 307                                      ch_priv->dma_ring_size);
 308         if (!ch_priv->dma_ring)
 309                 return -ENOMEM;
 310
 311         /* init channel config */
 312         ch_priv->running = false;
 313         ch_priv->desc_id = 0;
 314         if (bcm6348_iudma_chan_is_rx(dma->id)) {
 315                 ch_priv->desc_cnt = 0;
 316                 ch_priv->busy_desc = NULL;
 317         } else {
 318                 ch_priv->desc_cnt = ch_priv->dma_ring_size;
 319                 ch_priv->busy_desc = calloc(ch_priv->desc_cnt, sizeof(bool));
 320         }
 321
 322         return 0;
 323 }
 324
 325 static int bcm6348_iudma_receive(struct dma *dma, void **dst, void *metadata)
 326 {
 327         const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
 328         const struct bcm6348_iudma_hw *hw = priv->hw;
 329         struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
 330         struct bcm6348_dma_desc *dma_desc = dma_desc = ch_priv->dma_ring;
 331         int ret;
 332
 333         if (!ch_priv->running)
 334                 return -EINVAL;
 335
 336         /* get dma ring descriptor address */
 337         dma_desc += ch_priv->desc_id;
 338
 339         /* invalidate cache data */
 340         bcm6348_iudma_idc(dma_desc, sizeof(*dma_desc));
 341
 342         /* check dma own */
 343         if (dma_desc->status & DMAD_ST_OWN_MASK)
 344                 return -EAGAIN;
 345
 346         /* check pkt */
 347         if (!(dma_desc->status & DMAD_ST_EOP_MASK) ||
 348             !(dma_desc->status & DMAD_ST_SOP_MASK) ||
 349             (dma_desc->status & hw->err_mask)) {
 350                 pr_err("invalid pkt received (ch=%ld desc=%u) (st=%04x)\n",
 351                        dma->id, ch_priv->desc_id, dma_desc->status);
 352                 ret = -EAGAIN;
 353         } else {
 354                 /* set dma buffer address */
 355                 *dst = phys_to_virt(dma_desc->address);
 356
 357                 /* invalidate cache data */
 358                 bcm6348_iudma_idc(*dst, dma_desc->length);
 359
 360                 /* return packet length */
 361                 ret = dma_desc->length;
 362         }
 363
 364         /* busy dma descriptor */
 365         ch_priv->busy_desc[ch_priv->desc_id] = true;
 366
 367         /* increment dma descriptor */
 368         ch_priv->desc_id = (ch_priv->desc_id + 1) % ch_priv->desc_cnt;
 369
 370         return ret;
 371 }
 372
 373 static int bcm6348_iudma_send(struct dma *dma, void *src, size_t len,
 374                               void *metadata)
 375 {
 376         const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
 377         struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
 378         struct bcm6348_dma_desc *dma_desc;
 379         uint16_t status;
 380
 381         if (!ch_priv->running)
 382                 return -EINVAL;
 383
 384         /* flush cache */
 385         bcm6348_iudma_fdc(src, len);
 386
 387         /* get dma ring descriptor address */
 388         dma_desc = ch_priv->dma_ring;
 389         dma_desc += ch_priv->desc_id;
 390
 391         /* config dma descriptor */
 392         status = (DMAD_ST_OWN_MASK |
 393                   DMAD_ST_EOP_MASK |
 394                   DMAD_ST_CRC_MASK |
 395                   DMAD_ST_SOP_MASK);
 396         if (ch_priv->desc_id == ch_priv->desc_cnt - 1)
 397                 status |= DMAD_ST_WRAP_MASK;
 398
 399         /* set dma descriptor */
 400         dma_desc->address = virt_to_phys(src);
 401         dma_desc->length = len;
 402         dma_desc->status = status;
 403
 404         /* flush cache */
 405         bcm6348_iudma_fdc(dma_desc, sizeof(*dma_desc));
 406
 407         /* kick tx dma channel */
 408         setbits_be32(priv->chan + DMAC_CFG_REG(dma->id), DMAC_CFG_ENABLE_MASK);
 409
 410         /* poll dma status */
 411         do {
 412                 /* invalidate cache */
 413                 bcm6348_iudma_idc(dma_desc, sizeof(*dma_desc));
 414
 415                 if (!(dma_desc->status & DMAD_ST_OWN_MASK))
 416                         break;
 417         } while(1);
 418
 419         /* increment dma descriptor */
 420         ch_priv->desc_id = (ch_priv->desc_id + 1) % ch_priv->desc_cnt;
 421
 422         return 0;
 423 }
 424
 425 static int bcm6348_iudma_free_rcv_buf(struct dma *dma, void *dst, size_t size)
 426 {
 427         const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
 428         struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
 429         struct bcm6348_dma_desc *dma_desc = ch_priv->dma_ring;
 430         uint16_t status;
 431         uint8_t i;
 432         u32 cfg;
 433
 434         /* get dirty dma descriptor */
 435         for (i = 0; i < ch_priv->desc_cnt; i++) {
 436                 if (phys_to_virt(dma_desc->address) == dst)
 437                         break;
 438
 439                 dma_desc++;
 440         }
 441
 442         /* dma descriptor not found */
 443         if (i == ch_priv->desc_cnt) {
 444                 pr_err("dirty dma descriptor not found\n");
 445                 return -ENOENT;
 446         }
 447
 448         /* invalidate cache */
 449         bcm6348_iudma_idc(ch_priv->dma_ring,
 450                           sizeof(*dma_desc) * ch_priv->desc_cnt);
 451
 452         /* free dma descriptor */
 453         ch_priv->busy_desc[i] = false;
 454
 455         status = DMAD_ST_OWN_MASK;
 456         if (i == ch_priv->desc_cnt - 1)
 457                 status |= DMAD_ST_WRAP_MASK;
 458
 459         dma_desc->status |= status;
 460         dma_desc->length = PKTSIZE_ALIGN;
 461
 462         /* tell dma we allocated one buffer */
 463         writel_be(1, DMA_FLOWC_ALLOC_REG(dma->id));
 464
 465         /* flush cache */
 466         bcm6348_iudma_fdc(ch_priv->dma_ring,
 467                           sizeof(*dma_desc) * ch_priv->desc_cnt);
 468
 469         /* kick rx dma channel if disabled */
 470         cfg = readl_be(priv->chan + DMAC_CFG_REG(dma->id));
 471         if (!(cfg & DMAC_CFG_ENABLE_MASK))
 472                 setbits_be32(priv->chan + DMAC_CFG_REG(dma->id),
 473                              DMAC_CFG_ENABLE_MASK);
 474
 475         return 0;
 476 }
 477
 478 static int bcm6348_iudma_add_rcv_buf(struct dma *dma, void *dst, size_t size)
 479 {
 480         const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
 481         struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
 482         struct bcm6348_dma_desc *dma_desc = ch_priv->dma_ring;
 483
 484         /* no more dma descriptors available */
 485         if (ch_priv->desc_cnt == ch_priv->dma_ring_size) {
 486                 pr_err("max number of buffers reached\n");
 487                 return -EINVAL;
 488         }
 489
 490         /* get next dma descriptor */
 491         dma_desc += ch_priv->desc_cnt;
 492
 493         /* init dma descriptor */
 494         dma_desc->address = virt_to_phys(dst);
 495         dma_desc->length = size;
 496         dma_desc->status = 0;
 497
 498         /* flush cache */
 499         bcm6348_iudma_fdc(dma_desc, sizeof(*dma_desc));
 500
 501         /* increment dma descriptors */
 502         ch_priv->desc_cnt++;
 503
 504         return 0;
 505 }
 506
 507 static int bcm6348_iudma_prepare_rcv_buf(struct dma *dma, void *dst,
 508                                          size_t size)
 509 {
 510         const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
 511         struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
 512
 513         /* only add new rx buffers if channel isn't running */
 514         if (ch_priv->running)
 515                 return bcm6348_iudma_free_rcv_buf(dma, dst, size);
 516         else
 517                 return bcm6348_iudma_add_rcv_buf(dma, dst, size);
 518 }
 519
 520 static const struct dma_ops bcm6348_iudma_ops = {
 521         .disable = bcm6348_iudma_disable,
 522         .enable = bcm6348_iudma_enable,
 523         .prepare_rcv_buf = bcm6348_iudma_prepare_rcv_buf,
 524         .request = bcm6348_iudma_request,
 525         .receive = bcm6348_iudma_receive,
 526         .send = bcm6348_iudma_send,
 527 };
 528
 529 static const struct bcm6348_iudma_hw bcm6348_hw = {
 530         .err_mask = (DMAD6348_ST_OV_ERR_MASK |
 531                      DMAD6348_ST_CRC_ERR_MASK |
 532                      DMAD6348_ST_RX_ERR_MASK |
 533                      DMAD6348_ST_OS_ERR_MASK |
 534                      DMAD6348_ST_UN_ERR_MASK),
 535 };
 536
 537 static const struct bcm6348_iudma_hw bcm6368_hw = {
 538         .err_mask = 0,
 539 };
 540
 541 static const struct udevice_id bcm6348_iudma_ids[] = {
 542         {
 543                 .compatible = "brcm,bcm6348-iudma",
 544                 .data = (ulong)&bcm6348_hw,
 545         }, {
 546                 .compatible = "brcm,bcm6368-iudma",
 547                 .data = (ulong)&bcm6368_hw,
 548         }, { /* sentinel */ }
 549 };
 550
 551 static int bcm6348_iudma_probe(struct udevice *dev)
 552 {
 553         struct dma_dev_priv *uc_priv = dev_get_uclass_priv(dev);
 554         struct bcm6348_iudma_priv *priv = dev_get_priv(dev);
 555         const struct bcm6348_iudma_hw *hw =
 556                 (const struct bcm6348_iudma_hw *)dev_get_driver_data(dev);
 557         uint8_t ch;
 558         int i;
 559
 560         uc_priv->supported = (DMA_SUPPORTS_DEV_TO_MEM |
 561                               DMA_SUPPORTS_MEM_TO_DEV);
 562         priv->hw = hw;
 563
 564         /* dma global base address */
 565         priv->base = dev_remap_addr_name(dev, "dma");
 566         if (!priv->base)
 567                 return -EINVAL;
 568
 569         /* dma channels base address */
 570         priv->chan = dev_remap_addr_name(dev, "dma-channels");
 571         if (!priv->chan)
 572                 return -EINVAL;
 573
 574         /* dma sram base address */
 575         priv->sram = dev_remap_addr_name(dev, "dma-sram");
 576         if (!priv->sram)
 577                 return -EINVAL;
 578
 579         /* get number of channels */
 580         priv->n_channels = dev_read_u32_default(dev, "dma-channels", 8);
 581         if (priv->n_channels > DMA_CHAN_MAX)
 582                 return -EINVAL;
 583
 584         /* try to enable clocks */
 585         for (i = 0; ; i++) {
 586                 struct clk clk;
 587                 int ret;
 588
 589                 ret = clk_get_by_index(dev, i, &clk);
 590                 if (ret < 0)
 591                         break;
 592
 593                 ret = clk_enable(&clk);
 594                 if (ret < 0) {
 595                         pr_err("error enabling clock %d\n", i);
 596                         return ret;
 597                 }
 598         }
 599
 600         /* try to perform resets */
 601         for (i = 0; ; i++) {
 602                 struct reset_ctl reset;
 603                 int ret;
 604
 605                 ret = reset_get_by_index(dev, i, &reset);
 606                 if (ret < 0)
 607                         break;
 608
 609                 ret = reset_deassert(&reset);
 610                 if (ret < 0) {
 611                         pr_err("error deasserting reset %d\n", i);
 612                         return ret;
 613                 }
 614
 615                 ret = reset_free(&reset);
 616                 if (ret < 0) {
 617                         pr_err("error freeing reset %d\n", i);
 618                         return ret;
 619                 }
 620         }
 621
 622         /* disable dma controller */
 623         clrbits_be32(priv->base + DMA_CFG_REG, DMA_CFG_ENABLE_MASK);
 624
 625         /* alloc channel private data pointers */
 626         priv->ch_priv = calloc(priv->n_channels,
 627                                sizeof(struct bcm6348_chan_priv*));
 628         if (!priv->ch_priv)
 629                 return -ENOMEM;
 630
 631         /* stop dma channels */
 632         for (ch = 0; ch < priv->n_channels; ch++)
 633                 bcm6348_iudma_chan_stop(priv, ch);
 634
 635         /* enable dma controller */
 636         setbits_be32(priv->base + DMA_CFG_REG, DMA_CFG_ENABLE_MASK);
 637
 638         return 0;
 639 }
 640
 641 U_BOOT_DRIVER(bcm6348_iudma) = {
 642         .name = "bcm6348_iudma",
 643         .id = UCLASS_DMA,
 644         .of_match = bcm6348_iudma_ids,
 645         .ops = &bcm6348_iudma_ops,
 646         .priv_auto      = sizeof(struct bcm6348_iudma_priv),
 647         .probe = bcm6348_iudma_probe,
 648 };