linux/arch/m68k/include/asm/dma.h
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   1#ifndef _M68K_DMA_H
   2#define _M68K_DMA_H 1
   3
   4#ifdef CONFIG_COLDFIRE
   5/*
   6 * ColdFire DMA Model:
   7 *   ColdFire DMA supports two forms of DMA: Single and Dual address. Single
   8 * address mode emits a source address, and expects that the device will either
   9 * pick up the data (DMA READ) or source data (DMA WRITE). This implies that
  10 * the device will place data on the correct byte(s) of the data bus, as the
  11 * memory transactions are always 32 bits. This implies that only 32 bit
  12 * devices will find single mode transfers useful. Dual address DMA mode
  13 * performs two cycles: source read and destination write. ColdFire will
  14 * align the data so that the device will always get the correct bytes, thus
  15 * is useful for 8 and 16 bit devices. This is the mode that is supported
  16 * below.
  17 *
  18 * AUG/22/2000 : added support for 32-bit Dual-Address-Mode (K) 2000
  19 *               Oliver Kamphenkel (O.Kamphenkel@tu-bs.de)
  20 *
  21 * AUG/25/2000 : addad support for 8, 16 and 32-bit Single-Address-Mode (K)2000
  22 *               Oliver Kamphenkel (O.Kamphenkel@tu-bs.de)
  23 *
  24 * APR/18/2002 : added proper support for MCF5272 DMA controller.
  25 *               Arthur Shipkowski (art@videon-central.com)
  26 */
  27
  28#include <asm/coldfire.h>
  29#include <asm/mcfsim.h>
  30#include <asm/mcfdma.h>
  31
  32/*
  33 * Set number of channels of DMA on ColdFire for different implementations.
  34 */
  35#if defined(CONFIG_M5249) || defined(CONFIG_M5307) || defined(CONFIG_M5407) || \
  36        defined(CONFIG_M523x) || defined(CONFIG_M527x) || defined(CONFIG_M528x)
  37#define MAX_M68K_DMA_CHANNELS 4
  38#elif defined(CONFIG_M5272)
  39#define MAX_M68K_DMA_CHANNELS 1
  40#elif defined(CONFIG_M532x)
  41#define MAX_M68K_DMA_CHANNELS 0
  42#else
  43#define MAX_M68K_DMA_CHANNELS 2
  44#endif
  45
  46extern unsigned int dma_base_addr[MAX_M68K_DMA_CHANNELS];
  47extern unsigned int dma_device_address[MAX_M68K_DMA_CHANNELS];
  48
  49#if !defined(CONFIG_M5272)
  50#define DMA_MODE_WRITE_BIT  0x01  /* Memory/IO to IO/Memory select */
  51#define DMA_MODE_WORD_BIT   0x02  /* 8 or 16 bit transfers */
  52#define DMA_MODE_LONG_BIT   0x04  /* or 32 bit transfers */
  53#define DMA_MODE_SINGLE_BIT 0x08  /* single-address-mode */
  54
  55/* I/O to memory, 8 bits, mode */
  56#define DMA_MODE_READ               0
  57/* memory to I/O, 8 bits, mode */
  58#define DMA_MODE_WRITE              1
  59/* I/O to memory, 16 bits, mode */
  60#define DMA_MODE_READ_WORD          2
  61/* memory to I/O, 16 bits, mode */
  62#define DMA_MODE_WRITE_WORD         3
  63/* I/O to memory, 32 bits, mode */
  64#define DMA_MODE_READ_LONG          4
  65/* memory to I/O, 32 bits, mode */
  66#define DMA_MODE_WRITE_LONG         5
  67/* I/O to memory, 8 bits, single-address-mode */
  68#define DMA_MODE_READ_SINGLE        8
  69/* memory to I/O, 8 bits, single-address-mode */
  70#define DMA_MODE_WRITE_SINGLE       9
  71/* I/O to memory, 16 bits, single-address-mode */
  72#define DMA_MODE_READ_WORD_SINGLE  10
  73/* memory to I/O, 16 bits, single-address-mode */
  74#define DMA_MODE_WRITE_WORD_SINGLE 11
  75/* I/O to memory, 32 bits, single-address-mode */
  76#define DMA_MODE_READ_LONG_SINGLE  12
  77/* memory to I/O, 32 bits, single-address-mode */
  78#define DMA_MODE_WRITE_LONG_SINGLE 13
  79
  80#else /* CONFIG_M5272 is defined */
  81
  82/* Source static-address mode */
  83#define DMA_MODE_SRC_SA_BIT 0x01
  84/* Two bits to select between all four modes */
  85#define DMA_MODE_SSIZE_MASK 0x06
  86/* Offset to shift bits in */
  87#define DMA_MODE_SSIZE_OFF  0x01
  88/* Destination static-address mode */
  89#define DMA_MODE_DES_SA_BIT 0x10
  90/* Two bits to select between all four modes */
  91#define DMA_MODE_DSIZE_MASK 0x60
  92/* Offset to shift bits in */
  93#define DMA_MODE_DSIZE_OFF  0x05
  94/* Size modifiers */
  95#define DMA_MODE_SIZE_LONG  0x00
  96#define DMA_MODE_SIZE_BYTE  0x01
  97#define DMA_MODE_SIZE_WORD  0x02
  98#define DMA_MODE_SIZE_LINE  0x03
  99
 100/*
 101 * Aliases to help speed quick ports; these may be suboptimal, however. They
 102 * do not include the SINGLE mode modifiers since the MCF5272 does not have a
 103 * mode where the device is in control of its addressing.
 104 */
 105
 106/* I/O to memory, 8 bits, mode */
 107#define DMA_MODE_READ                 ((DMA_MODE_SIZE_BYTE << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_BYTE << DMA_MODE_SSIZE_OFF) | DMA_SRC_SA_BIT)
 108/* memory to I/O, 8 bits, mode */
 109#define DMA_MODE_WRITE              ((DMA_MODE_SIZE_BYTE << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_BYTE << DMA_MODE_SSIZE_OFF) | DMA_DES_SA_BIT)
 110/* I/O to memory, 16 bits, mode */
 111#define DMA_MODE_READ_WORD              ((DMA_MODE_SIZE_WORD << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_WORD << DMA_MODE_SSIZE_OFF) | DMA_SRC_SA_BIT)
 112/* memory to I/O, 16 bits, mode */
 113#define DMA_MODE_WRITE_WORD         ((DMA_MODE_SIZE_WORD << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_WORD << DMA_MODE_SSIZE_OFF) | DMA_DES_SA_BIT)
 114/* I/O to memory, 32 bits, mode */
 115#define DMA_MODE_READ_LONG              ((DMA_MODE_SIZE_LONG << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_LONG << DMA_MODE_SSIZE_OFF) | DMA_SRC_SA_BIT)
 116/* memory to I/O, 32 bits, mode */
 117#define DMA_MODE_WRITE_LONG         ((DMA_MODE_SIZE_LONG << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_LONG << DMA_MODE_SSIZE_OFF) | DMA_DES_SA_BIT)
 118
 119#endif /* !defined(CONFIG_M5272) */
 120
 121#if !defined(CONFIG_M5272)
 122/* enable/disable a specific DMA channel */
 123static __inline__ void enable_dma(unsigned int dmanr)
 124{
 125  volatile unsigned short *dmawp;
 126
 127#ifdef DMA_DEBUG
 128  printk("enable_dma(dmanr=%d)\n", dmanr);
 129#endif
 130
 131  dmawp = (unsigned short *) dma_base_addr[dmanr];
 132  dmawp[MCFDMA_DCR] |= MCFDMA_DCR_EEXT;
 133}
 134
 135static __inline__ void disable_dma(unsigned int dmanr)
 136{
 137  volatile unsigned short *dmawp;
 138  volatile unsigned char  *dmapb;
 139
 140#ifdef DMA_DEBUG
 141  printk("disable_dma(dmanr=%d)\n", dmanr);
 142#endif
 143
 144  dmawp = (unsigned short *) dma_base_addr[dmanr];
 145  dmapb = (unsigned char *) dma_base_addr[dmanr];
 146
 147  /* Turn off external requests, and stop any DMA in progress */
 148  dmawp[MCFDMA_DCR] &= ~MCFDMA_DCR_EEXT;
 149  dmapb[MCFDMA_DSR] = MCFDMA_DSR_DONE;
 150}
 151
 152/*
 153 * Clear the 'DMA Pointer Flip Flop'.
 154 * Write 0 for LSB/MSB, 1 for MSB/LSB access.
 155 * Use this once to initialize the FF to a known state.
 156 * After that, keep track of it. :-)
 157 * --- In order to do that, the DMA routines below should ---
 158 * --- only be used while interrupts are disabled! ---
 159 *
 160 * This is a NOP for ColdFire. Provide a stub for compatibility.
 161 */
 162static __inline__ void clear_dma_ff(unsigned int dmanr)
 163{
 164}
 165
 166/* set mode (above) for a specific DMA channel */
 167static __inline__ void set_dma_mode(unsigned int dmanr, char mode)
 168{
 169
 170  volatile unsigned char  *dmabp;
 171  volatile unsigned short *dmawp;
 172
 173#ifdef DMA_DEBUG
 174  printk("set_dma_mode(dmanr=%d,mode=%d)\n", dmanr, mode);
 175#endif
 176
 177  dmabp = (unsigned char *) dma_base_addr[dmanr];
 178  dmawp = (unsigned short *) dma_base_addr[dmanr];
 179
 180  /* Clear config errors */
 181  dmabp[MCFDMA_DSR] = MCFDMA_DSR_DONE;
 182
 183  /* Set command register */
 184  dmawp[MCFDMA_DCR] =
 185    MCFDMA_DCR_INT |         /* Enable completion irq */
 186    MCFDMA_DCR_CS |          /* Force one xfer per request */
 187    MCFDMA_DCR_AA |          /* Enable auto alignment */
 188    /* single-address-mode */
 189    ((mode & DMA_MODE_SINGLE_BIT) ? MCFDMA_DCR_SAA : 0) |
 190    /* sets s_rw (-> r/w) high if Memory to I/0 */
 191    ((mode & DMA_MODE_WRITE_BIT) ? MCFDMA_DCR_S_RW : 0) |
 192    /* Memory to I/O or I/O to Memory */
 193    ((mode & DMA_MODE_WRITE_BIT) ? MCFDMA_DCR_SINC : MCFDMA_DCR_DINC) |
 194    /* 32 bit, 16 bit or 8 bit transfers */
 195    ((mode & DMA_MODE_WORD_BIT)  ? MCFDMA_DCR_SSIZE_WORD :
 196     ((mode & DMA_MODE_LONG_BIT) ? MCFDMA_DCR_SSIZE_LONG :
 197                                   MCFDMA_DCR_SSIZE_BYTE)) |
 198    ((mode & DMA_MODE_WORD_BIT)  ? MCFDMA_DCR_DSIZE_WORD :
 199     ((mode & DMA_MODE_LONG_BIT) ? MCFDMA_DCR_DSIZE_LONG :
 200                                   MCFDMA_DCR_DSIZE_BYTE));
 201
 202#ifdef DEBUG_DMA
 203  printk("%s(%d): dmanr=%d DSR[%x]=%x DCR[%x]=%x\n", __FILE__, __LINE__,
 204         dmanr, (int) &dmabp[MCFDMA_DSR], dmabp[MCFDMA_DSR],
 205         (int) &dmawp[MCFDMA_DCR], dmawp[MCFDMA_DCR]);
 206#endif
 207}
 208
 209/* Set transfer address for specific DMA channel */
 210static __inline__ void set_dma_addr(unsigned int dmanr, unsigned int a)
 211{
 212  volatile unsigned short *dmawp;
 213  volatile unsigned int   *dmalp;
 214
 215#ifdef DMA_DEBUG
 216  printk("set_dma_addr(dmanr=%d,a=%x)\n", dmanr, a);
 217#endif
 218
 219  dmawp = (unsigned short *) dma_base_addr[dmanr];
 220  dmalp = (unsigned int *) dma_base_addr[dmanr];
 221
 222  /* Determine which address registers are used for memory/device accesses */
 223  if (dmawp[MCFDMA_DCR] & MCFDMA_DCR_SINC) {
 224    /* Source incrementing, must be memory */
 225    dmalp[MCFDMA_SAR] = a;
 226    /* Set dest address, must be device */
 227    dmalp[MCFDMA_DAR] = dma_device_address[dmanr];
 228  } else {
 229    /* Destination incrementing, must be memory */
 230    dmalp[MCFDMA_DAR] = a;
 231    /* Set source address, must be device */
 232    dmalp[MCFDMA_SAR] = dma_device_address[dmanr];
 233  }
 234
 235#ifdef DEBUG_DMA
 236  printk("%s(%d): dmanr=%d DCR[%x]=%x SAR[%x]=%08x DAR[%x]=%08x\n",
 237        __FILE__, __LINE__, dmanr, (int) &dmawp[MCFDMA_DCR], dmawp[MCFDMA_DCR],
 238        (int) &dmalp[MCFDMA_SAR], dmalp[MCFDMA_SAR],
 239        (int) &dmalp[MCFDMA_DAR], dmalp[MCFDMA_DAR]);
 240#endif
 241}
 242
 243/*
 244 * Specific for Coldfire - sets device address.
 245 * Should be called after the mode set call, and before set DMA address.
 246 */
 247static __inline__ void set_dma_device_addr(unsigned int dmanr, unsigned int a)
 248{
 249#ifdef DMA_DEBUG
 250  printk("set_dma_device_addr(dmanr=%d,a=%x)\n", dmanr, a);
 251#endif
 252
 253  dma_device_address[dmanr] = a;
 254}
 255
 256/*
 257 * NOTE 2: "count" represents _bytes_.
 258 */
 259static __inline__ void set_dma_count(unsigned int dmanr, unsigned int count)
 260{
 261  volatile unsigned short *dmawp;
 262
 263#ifdef DMA_DEBUG
 264  printk("set_dma_count(dmanr=%d,count=%d)\n", dmanr, count);
 265#endif
 266
 267  dmawp = (unsigned short *) dma_base_addr[dmanr];
 268  dmawp[MCFDMA_BCR] = (unsigned short)count;
 269}
 270
 271/*
 272 * Get DMA residue count. After a DMA transfer, this
 273 * should return zero. Reading this while a DMA transfer is
 274 * still in progress will return unpredictable results.
 275 * Otherwise, it returns the number of _bytes_ left to transfer.
 276 */
 277static __inline__ int get_dma_residue(unsigned int dmanr)
 278{
 279  volatile unsigned short *dmawp;
 280  unsigned short count;
 281
 282#ifdef DMA_DEBUG
 283  printk("get_dma_residue(dmanr=%d)\n", dmanr);
 284#endif
 285
 286  dmawp = (unsigned short *) dma_base_addr[dmanr];
 287  count = dmawp[MCFDMA_BCR];
 288  return((int) count);
 289}
 290#else /* CONFIG_M5272 is defined */
 291
 292/*
 293 * The MCF5272 DMA controller is very different than the controller defined above
 294 * in terms of register mapping.  For instance, with the exception of the 16-bit
 295 * interrupt register (IRQ#85, for reference), all of the registers are 32-bit.
 296 *
 297 * The big difference, however, is the lack of device-requested DMA.  All modes
 298 * are dual address transfer, and there is no 'device' setup or direction bit.
 299 * You can DMA between a device and memory, between memory and memory, or even between
 300 * two devices directly, with any combination of incrementing and non-incrementing
 301 * addresses you choose.  This puts a crimp in distinguishing between the 'device
 302 * address' set up by set_dma_device_addr.
 303 *
 304 * Therefore, there are two options.  One is to use set_dma_addr and set_dma_device_addr,
 305 * which will act exactly as above in -- it will look to see if the source is set to
 306 * autoincrement, and if so it will make the source use the set_dma_addr value and the
 307 * destination the set_dma_device_addr value.  Otherwise the source will be set to the
 308 * set_dma_device_addr value and the destination will get the set_dma_addr value.
 309 *
 310 * The other is to use the provided set_dma_src_addr and set_dma_dest_addr functions
 311 * and make it explicit.  Depending on what you're doing, one of these two should work
 312 * for you, but don't mix them in the same transfer setup.
 313 */
 314
 315/* enable/disable a specific DMA channel */
 316static __inline__ void enable_dma(unsigned int dmanr)
 317{
 318  volatile unsigned int  *dmalp;
 319
 320#ifdef DMA_DEBUG
 321  printk("enable_dma(dmanr=%d)\n", dmanr);
 322#endif
 323
 324  dmalp = (unsigned int *) dma_base_addr[dmanr];
 325  dmalp[MCFDMA_DMR] |= MCFDMA_DMR_EN;
 326}
 327
 328static __inline__ void disable_dma(unsigned int dmanr)
 329{
 330  volatile unsigned int   *dmalp;
 331
 332#ifdef DMA_DEBUG
 333  printk("disable_dma(dmanr=%d)\n", dmanr);
 334#endif
 335
 336  dmalp = (unsigned int *) dma_base_addr[dmanr];
 337
 338  /* Turn off external requests, and stop any DMA in progress */
 339  dmalp[MCFDMA_DMR] &= ~MCFDMA_DMR_EN;
 340  dmalp[MCFDMA_DMR] |= MCFDMA_DMR_RESET;
 341}
 342
 343/*
 344 * Clear the 'DMA Pointer Flip Flop'.
 345 * Write 0 for LSB/MSB, 1 for MSB/LSB access.
 346 * Use this once to initialize the FF to a known state.
 347 * After that, keep track of it. :-)
 348 * --- In order to do that, the DMA routines below should ---
 349 * --- only be used while interrupts are disabled! ---
 350 *
 351 * This is a NOP for ColdFire. Provide a stub for compatibility.
 352 */
 353static __inline__ void clear_dma_ff(unsigned int dmanr)
 354{
 355}
 356
 357/* set mode (above) for a specific DMA channel */
 358static __inline__ void set_dma_mode(unsigned int dmanr, char mode)
 359{
 360
 361  volatile unsigned int   *dmalp;
 362  volatile unsigned short *dmawp;
 363
 364#ifdef DMA_DEBUG
 365  printk("set_dma_mode(dmanr=%d,mode=%d)\n", dmanr, mode);
 366#endif
 367  dmalp = (unsigned int *) dma_base_addr[dmanr];
 368  dmawp = (unsigned short *) dma_base_addr[dmanr];
 369
 370  /* Clear config errors */
 371  dmalp[MCFDMA_DMR] |= MCFDMA_DMR_RESET;
 372
 373  /* Set command register */
 374  dmalp[MCFDMA_DMR] =
 375    MCFDMA_DMR_RQM_DUAL |         /* Mandatory Request Mode setting */
 376    MCFDMA_DMR_DSTT_SD  |         /* Set up addressing types; set to supervisor-data. */
 377    MCFDMA_DMR_SRCT_SD  |         /* Set up addressing types; set to supervisor-data. */
 378    /* source static-address-mode */
 379    ((mode & DMA_MODE_SRC_SA_BIT) ? MCFDMA_DMR_SRCM_SA : MCFDMA_DMR_SRCM_IA) |
 380    /* dest static-address-mode */
 381    ((mode & DMA_MODE_DES_SA_BIT) ? MCFDMA_DMR_DSTM_SA : MCFDMA_DMR_DSTM_IA) |
 382    /* burst, 32 bit, 16 bit or 8 bit transfers are separately configurable on the MCF5272 */
 383    (((mode & DMA_MODE_SSIZE_MASK) >> DMA_MODE_SSIZE_OFF) << MCFDMA_DMR_DSTS_OFF) |
 384    (((mode & DMA_MODE_SSIZE_MASK) >> DMA_MODE_SSIZE_OFF) << MCFDMA_DMR_SRCS_OFF);
 385
 386  dmawp[MCFDMA_DIR] |= MCFDMA_DIR_ASCEN;   /* Enable completion interrupts */
 387
 388#ifdef DEBUG_DMA
 389  printk("%s(%d): dmanr=%d DMR[%x]=%x DIR[%x]=%x\n", __FILE__, __LINE__,
 390         dmanr, (int) &dmalp[MCFDMA_DMR], dmabp[MCFDMA_DMR],
 391         (int) &dmawp[MCFDMA_DIR], dmawp[MCFDMA_DIR]);
 392#endif
 393}
 394
 395/* Set transfer address for specific DMA channel */
 396static __inline__ void set_dma_addr(unsigned int dmanr, unsigned int a)
 397{
 398  volatile unsigned int   *dmalp;
 399
 400#ifdef DMA_DEBUG
 401  printk("set_dma_addr(dmanr=%d,a=%x)\n", dmanr, a);
 402#endif
 403
 404  dmalp = (unsigned int *) dma_base_addr[dmanr];
 405
 406  /* Determine which address registers are used for memory/device accesses */
 407  if (dmalp[MCFDMA_DMR] & MCFDMA_DMR_SRCM) {
 408    /* Source incrementing, must be memory */
 409    dmalp[MCFDMA_DSAR] = a;
 410    /* Set dest address, must be device */
 411    dmalp[MCFDMA_DDAR] = dma_device_address[dmanr];
 412  } else {
 413    /* Destination incrementing, must be memory */
 414    dmalp[MCFDMA_DDAR] = a;
 415    /* Set source address, must be device */
 416    dmalp[MCFDMA_DSAR] = dma_device_address[dmanr];
 417  }
 418
 419#ifdef DEBUG_DMA
 420  printk("%s(%d): dmanr=%d DMR[%x]=%x SAR[%x]=%08x DAR[%x]=%08x\n",
 421        __FILE__, __LINE__, dmanr, (int) &dmawp[MCFDMA_DMR], dmawp[MCFDMA_DMR],
 422        (int) &dmalp[MCFDMA_DSAR], dmalp[MCFDMA_DSAR],
 423        (int) &dmalp[MCFDMA_DDAR], dmalp[MCFDMA_DDAR]);
 424#endif
 425}
 426
 427/*
 428 * Specific for Coldfire - sets device address.
 429 * Should be called after the mode set call, and before set DMA address.
 430 */
 431static __inline__ void set_dma_device_addr(unsigned int dmanr, unsigned int a)
 432{
 433#ifdef DMA_DEBUG
 434  printk("set_dma_device_addr(dmanr=%d,a=%x)\n", dmanr, a);
 435#endif
 436
 437  dma_device_address[dmanr] = a;
 438}
 439
 440/*
 441 * NOTE 2: "count" represents _bytes_.
 442 *
 443 * NOTE 3: While a 32-bit register, "count" is only a maximum 24-bit value.
 444 */
 445static __inline__ void set_dma_count(unsigned int dmanr, unsigned int count)
 446{
 447  volatile unsigned int *dmalp;
 448
 449#ifdef DMA_DEBUG
 450  printk("set_dma_count(dmanr=%d,count=%d)\n", dmanr, count);
 451#endif
 452
 453  dmalp = (unsigned int *) dma_base_addr[dmanr];
 454  dmalp[MCFDMA_DBCR] = count;
 455}
 456
 457/*
 458 * Get DMA residue count. After a DMA transfer, this
 459 * should return zero. Reading this while a DMA transfer is
 460 * still in progress will return unpredictable results.
 461 * Otherwise, it returns the number of _bytes_ left to transfer.
 462 */
 463static __inline__ int get_dma_residue(unsigned int dmanr)
 464{
 465  volatile unsigned int *dmalp;
 466  unsigned int count;
 467
 468#ifdef DMA_DEBUG
 469  printk("get_dma_residue(dmanr=%d)\n", dmanr);
 470#endif
 471
 472  dmalp = (unsigned int *) dma_base_addr[dmanr];
 473  count = dmalp[MCFDMA_DBCR];
 474  return(count);
 475}
 476
 477#endif /* !defined(CONFIG_M5272) */
 478#endif /* CONFIG_COLDFIRE */
 479
 480/* it's useless on the m68k, but unfortunately needed by the new
 481   bootmem allocator (but this should do it for this) */
 482#define MAX_DMA_ADDRESS PAGE_OFFSET
 483
 484#define MAX_DMA_CHANNELS 8
 485
 486extern int request_dma(unsigned int dmanr, const char * device_id);     /* reserve a DMA channel */
 487extern void free_dma(unsigned int dmanr);       /* release it again */
 488
 489#define isa_dma_bridge_buggy    (0)
 490
 491#endif /* _M68K_DMA_H */
 492