arch/mips/jazz/jazzdma.c

   1 /*
   2  * Mips Jazz DMA controller support
   3  * Copyright (C) 1995, 1996 by Andreas Busse
   4  *
   5  * NOTE: Some of the argument checking could be removed when
   6  * things have settled down. Also, instead of returning 0xffffffff
   7  * on failure of vdma_alloc() one could leave page #0 unused
   8  * and return the more usual NULL pointer as logical address.
   9  */
  10 #include <linux/kernel.h>
  11 #include <linux/init.h>
  12 #include <linux/module.h>
  13 #include <linux/errno.h>
  14 #include <linux/mm.h>
  15 #include <linux/bootmem.h>
  16 #include <linux/spinlock.h>
  17 #include <asm/mipsregs.h>
  18 #include <asm/jazz.h>
  19 #include <asm/io.h>
  20 #include <asm/uaccess.h>
  21 #include <asm/dma.h>
  22 #include <asm/jazzdma.h>
  23 #include <asm/pgtable.h>
  24
  25 /*
  26  * Set this to one to enable additional vdma debug code.
  27  */
  28 #define CONF_DEBUG_VDMA 0
  29
  30 static VDMA_PGTBL_ENTRY *pgtbl;
  31
  32 static DEFINE_SPINLOCK(vdma_lock);
  33
  34 /*
  35  * Debug stuff
  36  */
  37 #define vdma_debug     ((CONF_DEBUG_VDMA) ? debuglvl : 0)
  38
  39 static int debuglvl = 3;
  40
  41 /*
  42  * Initialize the pagetable with a one-to-one mapping of
  43  * the first 16 Mbytes of main memory and declare all
  44  * entries to be unused. Using this method will at least
  45  * allow some early device driver operations to work.
  46  */
  47 static inline void vdma_pgtbl_init(void)
  48 {
  49         unsigned long paddr = 0;
  50         int i;
  51
  52         for (i = 0; i < VDMA_PGTBL_ENTRIES; i++) {
  53                 pgtbl[i].frame = paddr;
  54                 pgtbl[i].owner = VDMA_PAGE_EMPTY;
  55                 paddr += VDMA_PAGESIZE;
  56         }
  57 }
  58
  59 /*
  60  * Initialize the Jazz R4030 dma controller
  61  */
  62 static int __init vdma_init(void)
  63 {
  64         /*
  65          * Allocate 32k of memory for DMA page tables.  This needs to be page
  66          * aligned and should be uncached to avoid cache flushing after every
  67          * update.
  68          */
  69         pgtbl = (VDMA_PGTBL_ENTRY *)__get_free_pages(GFP_KERNEL | GFP_DMA,
  70                                                     get_order(VDMA_PGTBL_SIZE));
  71         BUG_ON(!pgtbl);
  72         dma_cache_wback_inv((unsigned long)pgtbl, VDMA_PGTBL_SIZE);
  73         pgtbl = (VDMA_PGTBL_ENTRY *)KSEG1ADDR(pgtbl);
  74
  75         /*
  76          * Clear the R4030 translation table
  77          */
  78         vdma_pgtbl_init();
  79
  80         r4030_write_reg32(JAZZ_R4030_TRSTBL_BASE, CPHYSADDR(pgtbl));
  81         r4030_write_reg32(JAZZ_R4030_TRSTBL_LIM, VDMA_PGTBL_SIZE);
  82         r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);
  83
  84         printk(KERN_INFO "VDMA: R4030 DMA pagetables initialized.\n");
  85         return 0;
  86 }
  87
  88 /*
  89  * Allocate DMA pagetables using a simple first-fit algorithm
  90  */
  91 unsigned long vdma_alloc(unsigned long paddr, unsigned long size)
  92 {
  93         int first, last, pages, frame, i;
  94         unsigned long laddr, flags;
  95
  96         /* check arguments */
  97
  98         if (paddr > 0x1fffffff) {
  99                 if (vdma_debug)
 100                         printk("vdma_alloc: Invalid physical address: %08lx\n",
 101                                paddr);
 102                 return VDMA_ERROR;      /* invalid physical address */
 103         }
 104         if (size > 0x400000 || size == 0) {
 105                 if (vdma_debug)
 106                         printk("vdma_alloc: Invalid size: %08lx\n", size);
 107                 return VDMA_ERROR;      /* invalid physical address */
 108         }
 109
 110         spin_lock_irqsave(&vdma_lock, flags);
 111         /*
 112          * Find free chunk
 113          */
 114         pages = VDMA_PAGE(paddr + size) - VDMA_PAGE(paddr) + 1;
 115         first = 0;
 116         while (1) {
 117                 while (pgtbl[first].owner != VDMA_PAGE_EMPTY &&
 118                        first < VDMA_PGTBL_ENTRIES) first++;
 119                 if (first + pages > VDMA_PGTBL_ENTRIES) {       /* nothing free */
 120                         spin_unlock_irqrestore(&vdma_lock, flags);
 121                         return VDMA_ERROR;
 122                 }
 123
 124                 last = first + 1;
 125                 while (pgtbl[last].owner == VDMA_PAGE_EMPTY
 126                        && last - first < pages)
 127                         last++;
 128
 129                 if (last - first == pages)
 130                         break;  /* found */
 131                 first = last + 1;
 132         }
 133
 134         /*
 135          * Mark pages as allocated
 136          */
 137         laddr = (first << 12) + (paddr & (VDMA_PAGESIZE - 1));
 138         frame = paddr & ~(VDMA_PAGESIZE - 1);
 139
 140         for (i = first; i < last; i++) {
 141                 pgtbl[i].frame = frame;
 142                 pgtbl[i].owner = laddr;
 143                 frame += VDMA_PAGESIZE;
 144         }
 145
 146         /*
 147          * Update translation table and return logical start address
 148          */
 149         r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);
 150
 151         if (vdma_debug > 1)
 152                 printk("vdma_alloc: Allocated %d pages starting from %08lx\n",
 153                      pages, laddr);
 154
 155         if (vdma_debug > 2) {
 156                 printk("LADDR: ");
 157                 for (i = first; i < last; i++)
 158                         printk("%08x ", i << 12);
 159                 printk("\nPADDR: ");
 160                 for (i = first; i < last; i++)
 161                         printk("%08x ", pgtbl[i].frame);
 162                 printk("\nOWNER: ");
 163                 for (i = first; i < last; i++)
 164                         printk("%08x ", pgtbl[i].owner);
 165                 printk("\n");
 166         }
 167
 168         spin_unlock_irqrestore(&vdma_lock, flags);
 169
 170         return laddr;
 171 }
 172
 173 EXPORT_SYMBOL(vdma_alloc);
 174
 175 /*
 176  * Free previously allocated dma translation pages
 177  * Note that this does NOT change the translation table,
 178  * it just marks the free'd pages as unused!
 179  */
 180 int vdma_free(unsigned long laddr)
 181 {
 182         int i;
 183
 184         i = laddr >> 12;
 185
 186         if (pgtbl[i].owner != laddr) {
 187                 printk
 188                     ("vdma_free: trying to free other's dma pages, laddr=%8lx\n",
 189                      laddr);
 190                 return -1;
 191         }
 192
 193         while (pgtbl[i].owner == laddr && i < VDMA_PGTBL_ENTRIES) {
 194                 pgtbl[i].owner = VDMA_PAGE_EMPTY;
 195                 i++;
 196         }
 197
 198         if (vdma_debug > 1)
 199                 printk("vdma_free: freed %ld pages starting from %08lx\n",
 200                        i - (laddr >> 12), laddr);
 201
 202         return 0;
 203 }
 204
 205 EXPORT_SYMBOL(vdma_free);
 206
 207 /*
 208  * Map certain page(s) to another physical address.
 209  * Caller must have allocated the page(s) before.
 210  */
 211 int vdma_remap(unsigned long laddr, unsigned long paddr, unsigned long size)
 212 {
 213         int first, pages, npages;
 214
 215         if (laddr > 0xffffff) {
 216                 if (vdma_debug)
 217                         printk
 218                             ("vdma_map: Invalid logical address: %08lx\n",
 219                              laddr);
 220                 return -EINVAL; /* invalid logical address */
 221         }
 222         if (paddr > 0x1fffffff) {
 223                 if (vdma_debug)
 224                         printk
 225                             ("vdma_map: Invalid physical address: %08lx\n",
 226                              paddr);
 227                 return -EINVAL; /* invalid physical address */
 228         }
 229
 230         npages = pages =
 231             (((paddr & (VDMA_PAGESIZE - 1)) + size) >> 12) + 1;
 232         first = laddr >> 12;
 233         if (vdma_debug)
 234                 printk("vdma_remap: first=%x, pages=%x\n", first, pages);
 235         if (first + pages > VDMA_PGTBL_ENTRIES) {
 236                 if (vdma_debug)
 237                         printk("vdma_alloc: Invalid size: %08lx\n", size);
 238                 return -EINVAL;
 239         }
 240
 241         paddr &= ~(VDMA_PAGESIZE - 1);
 242         while (pages > 0 && first < VDMA_PGTBL_ENTRIES) {
 243                 if (pgtbl[first].owner != laddr) {
 244                         if (vdma_debug)
 245                                 printk("Trying to remap other's pages.\n");
 246                         return -EPERM;  /* not owner */
 247                 }
 248                 pgtbl[first].frame = paddr;
 249                 paddr += VDMA_PAGESIZE;
 250                 first++;
 251                 pages--;
 252         }
 253
 254         /*
 255          * Update translation table
 256          */
 257         r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);
 258
 259         if (vdma_debug > 2) {
 260                 int i;
 261                 pages = (((paddr & (VDMA_PAGESIZE - 1)) + size) >> 12) + 1;
 262                 first = laddr >> 12;
 263                 printk("LADDR: ");
 264                 for (i = first; i < first + pages; i++)
 265                         printk("%08x ", i << 12);
 266                 printk("\nPADDR: ");
 267                 for (i = first; i < first + pages; i++)
 268                         printk("%08x ", pgtbl[i].frame);
 269                 printk("\nOWNER: ");
 270                 for (i = first; i < first + pages; i++)
 271                         printk("%08x ", pgtbl[i].owner);
 272                 printk("\n");
 273         }
 274
 275         return 0;
 276 }
 277
 278 /*
 279  * Translate a physical address to a logical address.
 280  * This will return the logical address of the first
 281  * match.
 282  */
 283 unsigned long vdma_phys2log(unsigned long paddr)
 284 {
 285         int i;
 286         int frame;
 287
 288         frame = paddr & ~(VDMA_PAGESIZE - 1);
 289
 290         for (i = 0; i < VDMA_PGTBL_ENTRIES; i++) {
 291                 if (pgtbl[i].frame == frame)
 292                         break;
 293         }
 294
 295         if (i == VDMA_PGTBL_ENTRIES)
 296                 return ~0UL;
 297
 298         return (i << 12) + (paddr & (VDMA_PAGESIZE - 1));
 299 }
 300
 301 EXPORT_SYMBOL(vdma_phys2log);
 302
 303 /*
 304  * Translate a logical DMA address to a physical address
 305  */
 306 unsigned long vdma_log2phys(unsigned long laddr)
 307 {
 308         return pgtbl[laddr >> 12].frame + (laddr & (VDMA_PAGESIZE - 1));
 309 }
 310
 311 EXPORT_SYMBOL(vdma_log2phys);
 312
 313 /*
 314  * Print DMA statistics
 315  */
 316 void vdma_stats(void)
 317 {
 318         int i;
 319
 320         printk("vdma_stats: CONFIG: %08x\n",
 321                r4030_read_reg32(JAZZ_R4030_CONFIG));
 322         printk("R4030 translation table base: %08x\n",
 323                r4030_read_reg32(JAZZ_R4030_TRSTBL_BASE));
 324         printk("R4030 translation table limit: %08x\n",
 325                r4030_read_reg32(JAZZ_R4030_TRSTBL_LIM));
 326         printk("vdma_stats: INV_ADDR: %08x\n",
 327                r4030_read_reg32(JAZZ_R4030_INV_ADDR));
 328         printk("vdma_stats: R_FAIL_ADDR: %08x\n",
 329                r4030_read_reg32(JAZZ_R4030_R_FAIL_ADDR));
 330         printk("vdma_stats: M_FAIL_ADDR: %08x\n",
 331                r4030_read_reg32(JAZZ_R4030_M_FAIL_ADDR));
 332         printk("vdma_stats: IRQ_SOURCE: %08x\n",
 333                r4030_read_reg32(JAZZ_R4030_IRQ_SOURCE));
 334         printk("vdma_stats: I386_ERROR: %08x\n",
 335                r4030_read_reg32(JAZZ_R4030_I386_ERROR));
 336         printk("vdma_chnl_modes:   ");
 337         for (i = 0; i < 8; i++)
 338                 printk("%04x ",
 339                        (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_MODE +
 340                                                    (i << 5)));
 341         printk("\n");
 342         printk("vdma_chnl_enables: ");
 343         for (i = 0; i < 8; i++)
 344                 printk("%04x ",
 345                        (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
 346                                                    (i << 5)));
 347         printk("\n");
 348 }
 349
 350 /*
 351  * DMA transfer functions
 352  */
 353
 354 /*
 355  * Enable a DMA channel. Also clear any error conditions.
 356  */
 357 void vdma_enable(int channel)
 358 {
 359         int status;
 360
 361         if (vdma_debug)
 362                 printk("vdma_enable: channel %d\n", channel);
 363
 364         /*
 365          * Check error conditions first
 366          */
 367         status = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5));
 368         if (status & 0x400)
 369                 printk("VDMA: Channel %d: Address error!\n", channel);
 370         if (status & 0x200)
 371                 printk("VDMA: Channel %d: Memory error!\n", channel);
 372
 373         /*
 374          * Clear all interrupt flags
 375          */
 376         r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
 377                           r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
 378                                            (channel << 5)) | R4030_TC_INTR
 379                           | R4030_MEM_INTR | R4030_ADDR_INTR);
 380
 381         /*
 382          * Enable the desired channel
 383          */
 384         r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
 385                           r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
 386                                            (channel << 5)) |
 387                           R4030_CHNL_ENABLE);
 388 }
 389
 390 EXPORT_SYMBOL(vdma_enable);
 391
 392 /*
 393  * Disable a DMA channel
 394  */
 395 void vdma_disable(int channel)
 396 {
 397         if (vdma_debug) {
 398                 int status =
 399                     r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
 400                                      (channel << 5));
 401
 402                 printk("vdma_disable: channel %d\n", channel);
 403                 printk("VDMA: channel %d status: %04x (%s) mode: "
 404                        "%02x addr: %06x count: %06x\n",
 405                        channel, status,
 406                        ((status & 0x600) ? "ERROR" : "OK"),
 407                        (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_MODE +
 408                                                    (channel << 5)),
 409                        (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_ADDR +
 410                                                    (channel << 5)),
 411                        (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_COUNT +
 412                                                    (channel << 5)));
 413         }
 414
 415         r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
 416                           r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
 417                                            (channel << 5)) &
 418                           ~R4030_CHNL_ENABLE);
 419
 420         /*
 421          * After disabling a DMA channel a remote bus register should be
 422          * read to ensure that the current DMA acknowledge cycle is completed.
 423          */
 424         *((volatile unsigned int *) JAZZ_DUMMY_DEVICE);
 425 }
 426
 427 EXPORT_SYMBOL(vdma_disable);
 428
 429 /*
 430  * Set DMA mode. This function accepts the mode values used
 431  * to set a PC-style DMA controller. For the SCSI and FDC
 432  * channels, we also set the default modes each time we're
 433  * called.
 434  * NOTE: The FAST and BURST dma modes are supported by the
 435  * R4030 Rev. 2 and PICA chipsets only. I leave them disabled
 436  * for now.
 437  */
 438 void vdma_set_mode(int channel, int mode)
 439 {
 440         if (vdma_debug)
 441                 printk("vdma_set_mode: channel %d, mode 0x%x\n", channel,
 442                        mode);
 443
 444         switch (channel) {
 445         case JAZZ_SCSI_DMA:     /* scsi */
 446                 r4030_write_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5),
 447 /*                        R4030_MODE_FAST | */
 448 /*                        R4030_MODE_BURST | */
 449                                   R4030_MODE_INTR_EN |
 450                                   R4030_MODE_WIDTH_16 |
 451                                   R4030_MODE_ATIME_80);
 452                 break;
 453
 454         case JAZZ_FLOPPY_DMA:   /* floppy */
 455                 r4030_write_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5),
 456 /*                        R4030_MODE_FAST | */
 457 /*                        R4030_MODE_BURST | */
 458                                   R4030_MODE_INTR_EN |
 459                                   R4030_MODE_WIDTH_8 |
 460                                   R4030_MODE_ATIME_120);
 461                 break;
 462
 463         case JAZZ_AUDIOL_DMA:
 464         case JAZZ_AUDIOR_DMA:
 465                 printk("VDMA: Audio DMA not supported yet.\n");
 466                 break;
 467
 468         default:
 469                 printk
 470                     ("VDMA: vdma_set_mode() called with unsupported channel %d!\n",
 471                      channel);
 472         }
 473
 474         switch (mode) {
 475         case DMA_MODE_READ:
 476                 r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
 477                                   r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
 478                                                    (channel << 5)) &
 479                                   ~R4030_CHNL_WRITE);
 480                 break;
 481
 482         case DMA_MODE_WRITE:
 483                 r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
 484                                   r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
 485                                                    (channel << 5)) |
 486                                   R4030_CHNL_WRITE);
 487                 break;
 488
 489         default:
 490                 printk
 491                     ("VDMA: vdma_set_mode() called with unknown dma mode 0x%x\n",
 492                      mode);
 493         }
 494 }
 495
 496 EXPORT_SYMBOL(vdma_set_mode);
 497
 498 /*
 499  * Set Transfer Address
 500  */
 501 void vdma_set_addr(int channel, long addr)
 502 {
 503         if (vdma_debug)
 504                 printk("vdma_set_addr: channel %d, addr %lx\n", channel,
 505                        addr);
 506
 507         r4030_write_reg32(JAZZ_R4030_CHNL_ADDR + (channel << 5), addr);
 508 }
 509
 510 EXPORT_SYMBOL(vdma_set_addr);
 511
 512 /*
 513  * Set Transfer Count
 514  */
 515 void vdma_set_count(int channel, int count)
 516 {
 517         if (vdma_debug)
 518                 printk("vdma_set_count: channel %d, count %08x\n", channel,
 519                        (unsigned) count);
 520
 521         r4030_write_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5), count);
 522 }
 523
 524 EXPORT_SYMBOL(vdma_set_count);
 525
 526 /*
 527  * Get Residual
 528  */
 529 int vdma_get_residue(int channel)
 530 {
 531         int residual;
 532
 533         residual = r4030_read_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5));
 534
 535         if (vdma_debug)
 536                 printk("vdma_get_residual: channel %d: residual=%d\n",
 537                        channel, residual);
 538
 539         return residual;
 540 }
 541
 542 /*
 543  * Get DMA channel enable register
 544  */
 545 int vdma_get_enable(int channel)
 546 {
 547         int enable;
 548
 549         enable = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5));
 550
 551         if (vdma_debug)
 552                 printk("vdma_get_enable: channel %d: enable=%d\n", channel,
 553                        enable);
 554
 555         return enable;
 556 }
 557
 558 arch_initcall(vdma_init);