drivers/video/offb.c

   1 /*
   2  *  linux/drivers/video/offb.c -- Open Firmware based frame buffer device
   3  *
   4  *      Copyright (C) 1997 Geert Uytterhoeven
   5  *
   6  *  This driver is partly based on the PowerMac console driver:
   7  *
   8  *      Copyright (C) 1996 Paul Mackerras
   9  *
  10  *  This file is subject to the terms and conditions of the GNU General Public
  11  *  License. See the file COPYING in the main directory of this archive for
  12  *  more details.
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/kernel.h>
  17 #include <linux/errno.h>
  18 #include <linux/string.h>
  19 #include <linux/mm.h>
  20 #include <linux/vmalloc.h>
  21 #include <linux/delay.h>
  22 #include <linux/of.h>
  23 #include <linux/of_address.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/fb.h>
  26 #include <linux/init.h>
  27 #include <linux/ioport.h>
  28 #include <linux/pci.h>
  29 #include <asm/io.h>
  30
  31 #ifdef CONFIG_PPC64
  32 #include <asm/pci-bridge.h>
  33 #endif
  34
  35 #ifdef CONFIG_PPC32
  36 #include <asm/bootx.h>
  37 #endif
  38
  39 #include "macmodes.h"
  40
  41 /* Supported palette hacks */
  42 enum {
  43         cmap_unknown,
  44         cmap_simple,            /* ATI Mach64 */
  45         cmap_r128,              /* ATI Rage128 */
  46         cmap_M3A,               /* ATI Rage Mobility M3 Head A */
  47         cmap_M3B,               /* ATI Rage Mobility M3 Head B */
  48         cmap_radeon,            /* ATI Radeon */
  49         cmap_gxt2000,           /* IBM GXT2000 */
  50         cmap_avivo,             /* ATI R5xx */
  51         cmap_qemu,              /* qemu vga */
  52 };
  53
  54 struct offb_par {
  55         volatile void __iomem *cmap_adr;
  56         volatile void __iomem *cmap_data;
  57         int cmap_type;
  58         int blanked;
  59 };
  60
  61 struct offb_par default_par;
  62
  63 #ifdef CONFIG_PPC32
  64 extern boot_infos_t *boot_infos;
  65 #endif
  66
  67 /* Definitions used by the Avivo palette hack */
  68 #define AVIVO_DC_LUT_RW_SELECT                  0x6480
  69 #define AVIVO_DC_LUT_RW_MODE                    0x6484
  70 #define AVIVO_DC_LUT_RW_INDEX                   0x6488
  71 #define AVIVO_DC_LUT_SEQ_COLOR                  0x648c
  72 #define AVIVO_DC_LUT_PWL_DATA                   0x6490
  73 #define AVIVO_DC_LUT_30_COLOR                   0x6494
  74 #define AVIVO_DC_LUT_READ_PIPE_SELECT           0x6498
  75 #define AVIVO_DC_LUT_WRITE_EN_MASK              0x649c
  76 #define AVIVO_DC_LUT_AUTOFILL                   0x64a0
  77
  78 #define AVIVO_DC_LUTA_CONTROL                   0x64c0
  79 #define AVIVO_DC_LUTA_BLACK_OFFSET_BLUE         0x64c4
  80 #define AVIVO_DC_LUTA_BLACK_OFFSET_GREEN        0x64c8
  81 #define AVIVO_DC_LUTA_BLACK_OFFSET_RED          0x64cc
  82 #define AVIVO_DC_LUTA_WHITE_OFFSET_BLUE         0x64d0
  83 #define AVIVO_DC_LUTA_WHITE_OFFSET_GREEN        0x64d4
  84 #define AVIVO_DC_LUTA_WHITE_OFFSET_RED          0x64d8
  85
  86 #define AVIVO_DC_LUTB_CONTROL                   0x6cc0
  87 #define AVIVO_DC_LUTB_BLACK_OFFSET_BLUE         0x6cc4
  88 #define AVIVO_DC_LUTB_BLACK_OFFSET_GREEN        0x6cc8
  89 #define AVIVO_DC_LUTB_BLACK_OFFSET_RED          0x6ccc
  90 #define AVIVO_DC_LUTB_WHITE_OFFSET_BLUE         0x6cd0
  91 #define AVIVO_DC_LUTB_WHITE_OFFSET_GREEN        0x6cd4
  92 #define AVIVO_DC_LUTB_WHITE_OFFSET_RED          0x6cd8
  93
  94     /*
  95      *  Set a single color register. The values supplied are already
  96      *  rounded down to the hardware's capabilities (according to the
  97      *  entries in the var structure). Return != 0 for invalid regno.
  98      */
  99
 100 static int offb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
 101                           u_int transp, struct fb_info *info)
 102 {
 103         struct offb_par *par = (struct offb_par *) info->par;
 104
 105         if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
 106                 u32 *pal = info->pseudo_palette;
 107                 u32 cr = red >> (16 - info->var.red.length);
 108                 u32 cg = green >> (16 - info->var.green.length);
 109                 u32 cb = blue >> (16 - info->var.blue.length);
 110                 u32 value;
 111
 112                 if (regno >= 16)
 113                         return -EINVAL;
 114
 115                 value = (cr << info->var.red.offset) |
 116                         (cg << info->var.green.offset) |
 117                         (cb << info->var.blue.offset);
 118                 if (info->var.transp.length > 0) {
 119                         u32 mask = (1 << info->var.transp.length) - 1;
 120                         mask <<= info->var.transp.offset;
 121                         value |= mask;
 122                 }
 123                 pal[regno] = value;
 124                 return 0;
 125         }
 126
 127         if (regno > 255)
 128                 return -EINVAL;
 129
 130         red >>= 8;
 131         green >>= 8;
 132         blue >>= 8;
 133
 134         if (!par->cmap_adr)
 135                 return 0;
 136
 137         switch (par->cmap_type) {
 138         case cmap_simple:
 139                 writeb(regno, par->cmap_adr);
 140                 writeb(red, par->cmap_data);
 141                 writeb(green, par->cmap_data);
 142                 writeb(blue, par->cmap_data);
 143                 break;
 144         case cmap_M3A:
 145                 /* Clear PALETTE_ACCESS_CNTL in DAC_CNTL */
 146                 out_le32(par->cmap_adr + 0x58,
 147                          in_le32(par->cmap_adr + 0x58) & ~0x20);
 148         case cmap_r128:
 149                 /* Set palette index & data */
 150                 out_8(par->cmap_adr + 0xb0, regno);
 151                 out_le32(par->cmap_adr + 0xb4,
 152                          (red << 16 | green << 8 | blue));
 153                 break;
 154         case cmap_M3B:
 155                 /* Set PALETTE_ACCESS_CNTL in DAC_CNTL */
 156                 out_le32(par->cmap_adr + 0x58,
 157                          in_le32(par->cmap_adr + 0x58) | 0x20);
 158                 /* Set palette index & data */
 159                 out_8(par->cmap_adr + 0xb0, regno);
 160                 out_le32(par->cmap_adr + 0xb4, (red << 16 | green << 8 | blue));
 161                 break;
 162         case cmap_radeon:
 163                 /* Set palette index & data (could be smarter) */
 164                 out_8(par->cmap_adr + 0xb0, regno);
 165                 out_le32(par->cmap_adr + 0xb4, (red << 16 | green << 8 | blue));
 166                 break;
 167         case cmap_gxt2000:
 168                 out_le32(((unsigned __iomem *) par->cmap_adr) + regno,
 169                          (red << 16 | green << 8 | blue));
 170                 break;
 171         case cmap_avivo:
 172                 /* Write to both LUTs for now */
 173                 writel(1, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
 174                 writeb(regno, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
 175                 writel(((red) << 22) | ((green) << 12) | ((blue) << 2),
 176                        par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
 177                 writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
 178                 writeb(regno, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
 179                 writel(((red) << 22) | ((green) << 12) | ((blue) << 2),
 180                        par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
 181                 break;
 182         }
 183
 184         return 0;
 185 }
 186
 187     /*
 188      *  Blank the display.
 189      */
 190
 191 static int offb_blank(int blank, struct fb_info *info)
 192 {
 193         struct offb_par *par = (struct offb_par *) info->par;
 194         int i, j;
 195
 196         if (!par->cmap_adr)
 197                 return 0;
 198
 199         if (!par->blanked)
 200                 if (!blank)
 201                         return 0;
 202
 203         par->blanked = blank;
 204
 205         if (blank)
 206                 for (i = 0; i < 256; i++) {
 207                         switch (par->cmap_type) {
 208                         case cmap_simple:
 209                                 writeb(i, par->cmap_adr);
 210                                 for (j = 0; j < 3; j++)
 211                                         writeb(0, par->cmap_data);
 212                                 break;
 213                         case cmap_M3A:
 214                                 /* Clear PALETTE_ACCESS_CNTL in DAC_CNTL */
 215                                 out_le32(par->cmap_adr + 0x58,
 216                                          in_le32(par->cmap_adr + 0x58) & ~0x20);
 217                         case cmap_r128:
 218                                 /* Set palette index & data */
 219                                 out_8(par->cmap_adr + 0xb0, i);
 220                                 out_le32(par->cmap_adr + 0xb4, 0);
 221                                 break;
 222                         case cmap_M3B:
 223                                 /* Set PALETTE_ACCESS_CNTL in DAC_CNTL */
 224                                 out_le32(par->cmap_adr + 0x58,
 225                                          in_le32(par->cmap_adr + 0x58) | 0x20);
 226                                 /* Set palette index & data */
 227                                 out_8(par->cmap_adr + 0xb0, i);
 228                                 out_le32(par->cmap_adr + 0xb4, 0);
 229                                 break;
 230                         case cmap_radeon:
 231                                 out_8(par->cmap_adr + 0xb0, i);
 232                                 out_le32(par->cmap_adr + 0xb4, 0);
 233                                 break;
 234                         case cmap_gxt2000:
 235                                 out_le32(((unsigned __iomem *) par->cmap_adr) + i,
 236                                          0);
 237                                 break;
 238                         case cmap_avivo:
 239                                 writel(1, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
 240                                 writeb(i, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
 241                                 writel(0, par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
 242                                 writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
 243                                 writeb(i, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
 244                                 writel(0, par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
 245                                 break;
 246                         }
 247         } else
 248                 fb_set_cmap(&info->cmap, info);
 249         return 0;
 250 }
 251
 252 static int offb_set_par(struct fb_info *info)
 253 {
 254         struct offb_par *par = (struct offb_par *) info->par;
 255
 256         /* On avivo, initialize palette control */
 257         if (par->cmap_type == cmap_avivo) {
 258                 writel(0, par->cmap_adr + AVIVO_DC_LUTA_CONTROL);
 259                 writel(0, par->cmap_adr + AVIVO_DC_LUTA_BLACK_OFFSET_BLUE);
 260                 writel(0, par->cmap_adr + AVIVO_DC_LUTA_BLACK_OFFSET_GREEN);
 261                 writel(0, par->cmap_adr + AVIVO_DC_LUTA_BLACK_OFFSET_RED);
 262                 writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTA_WHITE_OFFSET_BLUE);
 263                 writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTA_WHITE_OFFSET_GREEN);
 264                 writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTA_WHITE_OFFSET_RED);
 265                 writel(0, par->cmap_adr + AVIVO_DC_LUTB_CONTROL);
 266                 writel(0, par->cmap_adr + AVIVO_DC_LUTB_BLACK_OFFSET_BLUE);
 267                 writel(0, par->cmap_adr + AVIVO_DC_LUTB_BLACK_OFFSET_GREEN);
 268                 writel(0, par->cmap_adr + AVIVO_DC_LUTB_BLACK_OFFSET_RED);
 269                 writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTB_WHITE_OFFSET_BLUE);
 270                 writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTB_WHITE_OFFSET_GREEN);
 271                 writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTB_WHITE_OFFSET_RED);
 272                 writel(1, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
 273                 writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_MODE);
 274                 writel(0x0000003f, par->cmap_adr + AVIVO_DC_LUT_WRITE_EN_MASK);
 275                 writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
 276                 writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_MODE);
 277                 writel(0x0000003f, par->cmap_adr + AVIVO_DC_LUT_WRITE_EN_MASK);
 278         }
 279         return 0;
 280 }
 281
 282 static void offb_destroy(struct fb_info *info)
 283 {
 284         if (info->screen_base)
 285                 iounmap(info->screen_base);
 286         release_mem_region(info->apertures->ranges[0].base, info->apertures->ranges[0].size);
 287         framebuffer_release(info);
 288 }
 289
 290 static struct fb_ops offb_ops = {
 291         .owner          = THIS_MODULE,
 292         .fb_destroy     = offb_destroy,
 293         .fb_setcolreg   = offb_setcolreg,
 294         .fb_set_par     = offb_set_par,
 295         .fb_blank       = offb_blank,
 296         .fb_fillrect    = cfb_fillrect,
 297         .fb_copyarea    = cfb_copyarea,
 298         .fb_imageblit   = cfb_imageblit,
 299 };
 300
 301 static void __iomem *offb_map_reg(struct device_node *np, int index,
 302                                   unsigned long offset, unsigned long size)
 303 {
 304         const u32 *addrp;
 305         u64 asize, taddr;
 306         unsigned int flags;
 307
 308         addrp = of_get_pci_address(np, index, &asize, &flags);
 309         if (addrp == NULL)
 310                 addrp = of_get_address(np, index, &asize, &flags);
 311         if (addrp == NULL)
 312                 return NULL;
 313         if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
 314                 return NULL;
 315         if ((offset + size) > asize)
 316                 return NULL;
 317         taddr = of_translate_address(np, addrp);
 318         if (taddr == OF_BAD_ADDR)
 319                 return NULL;
 320         return ioremap(taddr + offset, size);
 321 }
 322
 323 static void offb_init_palette_hacks(struct fb_info *info, struct device_node *dp,
 324                                     const char *name, unsigned long address)
 325 {
 326         struct offb_par *par = (struct offb_par *) info->par;
 327
 328         if (dp && !strncmp(name, "ATY,Rage128", 11)) {
 329                 par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
 330                 if (par->cmap_adr)
 331                         par->cmap_type = cmap_r128;
 332         } else if (dp && (!strncmp(name, "ATY,RageM3pA", 12)
 333                           || !strncmp(name, "ATY,RageM3p12A", 14))) {
 334                 par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
 335                 if (par->cmap_adr)
 336                         par->cmap_type = cmap_M3A;
 337         } else if (dp && !strncmp(name, "ATY,RageM3pB", 12)) {
 338                 par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
 339                 if (par->cmap_adr)
 340                         par->cmap_type = cmap_M3B;
 341         } else if (dp && !strncmp(name, "ATY,Rage6", 9)) {
 342                 par->cmap_adr = offb_map_reg(dp, 1, 0, 0x1fff);
 343                 if (par->cmap_adr)
 344                         par->cmap_type = cmap_radeon;
 345         } else if (!strncmp(name, "ATY,", 4)) {
 346                 unsigned long base = address & 0xff000000UL;
 347                 par->cmap_adr =
 348                         ioremap(base + 0x7ff000, 0x1000) + 0xcc0;
 349                 par->cmap_data = par->cmap_adr + 1;
 350                 par->cmap_type = cmap_simple;
 351         } else if (dp && (of_device_is_compatible(dp, "pci1014,b7") ||
 352                           of_device_is_compatible(dp, "pci1014,21c"))) {
 353                 par->cmap_adr = offb_map_reg(dp, 0, 0x6000, 0x1000);
 354                 if (par->cmap_adr)
 355                         par->cmap_type = cmap_gxt2000;
 356         } else if (dp && !strncmp(name, "vga,Display-", 12)) {
 357                 /* Look for AVIVO initialized by SLOF */
 358                 struct device_node *pciparent = of_get_parent(dp);
 359                 const u32 *vid, *did;
 360                 vid = of_get_property(pciparent, "vendor-id", NULL);
 361                 did = of_get_property(pciparent, "device-id", NULL);
 362                 /* This will match most R5xx */
 363                 if (vid && did && *vid == 0x1002 &&
 364                     ((*did >= 0x7100 && *did < 0x7800) ||
 365                      (*did >= 0x9400))) {
 366                         par->cmap_adr = offb_map_reg(pciparent, 2, 0, 0x10000);
 367                         if (par->cmap_adr)
 368                                 par->cmap_type = cmap_avivo;
 369                 }
 370                 of_node_put(pciparent);
 371         } else if (dp && of_device_is_compatible(dp, "qemu,std-vga")) {
 372                 const u32 io_of_addr[3] = { 0x01000000, 0x0, 0x0 };
 373                 u64 io_addr = of_translate_address(dp, io_of_addr);
 374                 if (io_addr != OF_BAD_ADDR) {
 375                         par->cmap_adr = ioremap(io_addr + 0x3c8, 2);
 376                         if (par->cmap_adr) {
 377                                 par->cmap_type = cmap_simple;
 378                                 par->cmap_data = par->cmap_adr + 1;
 379                         }
 380                 }
 381         }
 382         info->fix.visual = (par->cmap_type != cmap_unknown) ?
 383                 FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_STATIC_PSEUDOCOLOR;
 384 }
 385
 386 static void __init offb_init_fb(const char *name, const char *full_name,
 387                                 int width, int height, int depth,
 388                                 int pitch, unsigned long address,
 389                                 int foreign_endian, struct device_node *dp)
 390 {
 391         unsigned long res_size = pitch * height;
 392         struct offb_par *par = &default_par;
 393         unsigned long res_start = address;
 394         struct fb_fix_screeninfo *fix;
 395         struct fb_var_screeninfo *var;
 396         struct fb_info *info;
 397
 398         if (!request_mem_region(res_start, res_size, "offb"))
 399                 return;
 400
 401         printk(KERN_INFO
 402                "Using unsupported %dx%d %s at %lx, depth=%d, pitch=%d\n",
 403                width, height, name, address, depth, pitch);
 404         if (depth != 8 && depth != 15 && depth != 16 && depth != 32) {
 405                 printk(KERN_ERR "%s: can't use depth = %d\n", full_name,
 406                        depth);
 407                 release_mem_region(res_start, res_size);
 408                 return;
 409         }
 410
 411         info = framebuffer_alloc(sizeof(u32) * 16, NULL);
 412
 413         if (info == 0) {
 414                 release_mem_region(res_start, res_size);
 415                 return;
 416         }
 417
 418         fix = &info->fix;
 419         var = &info->var;
 420         info->par = par;
 421
 422         strcpy(fix->id, "OFfb ");
 423         strncat(fix->id, name, sizeof(fix->id) - sizeof("OFfb "));
 424         fix->id[sizeof(fix->id) - 1] = '\0';
 425
 426         var->xres = var->xres_virtual = width;
 427         var->yres = var->yres_virtual = height;
 428         fix->line_length = pitch;
 429
 430         fix->smem_start = address;
 431         fix->smem_len = pitch * height;
 432         fix->type = FB_TYPE_PACKED_PIXELS;
 433         fix->type_aux = 0;
 434
 435         par->cmap_type = cmap_unknown;
 436         if (depth == 8)
 437                 offb_init_palette_hacks(info, dp, name, address);
 438         else
 439                 fix->visual = FB_VISUAL_TRUECOLOR;
 440
 441         var->xoffset = var->yoffset = 0;
 442         switch (depth) {
 443         case 8:
 444                 var->bits_per_pixel = 8;
 445                 var->red.offset = 0;
 446                 var->red.length = 8;
 447                 var->green.offset = 0;
 448                 var->green.length = 8;
 449                 var->blue.offset = 0;
 450                 var->blue.length = 8;
 451                 var->transp.offset = 0;
 452                 var->transp.length = 0;
 453                 break;
 454         case 15:                /* RGB 555 */
 455                 var->bits_per_pixel = 16;
 456                 var->red.offset = 10;
 457                 var->red.length = 5;
 458                 var->green.offset = 5;
 459                 var->green.length = 5;
 460                 var->blue.offset = 0;
 461                 var->blue.length = 5;
 462                 var->transp.offset = 0;
 463                 var->transp.length = 0;
 464                 break;
 465         case 16:                /* RGB 565 */
 466                 var->bits_per_pixel = 16;
 467                 var->red.offset = 11;
 468                 var->red.length = 5;
 469                 var->green.offset = 5;
 470                 var->green.length = 6;
 471                 var->blue.offset = 0;
 472                 var->blue.length = 5;
 473                 var->transp.offset = 0;
 474                 var->transp.length = 0;
 475                 break;
 476         case 32:                /* RGB 888 */
 477                 var->bits_per_pixel = 32;
 478                 var->red.offset = 16;
 479                 var->red.length = 8;
 480                 var->green.offset = 8;
 481                 var->green.length = 8;
 482                 var->blue.offset = 0;
 483                 var->blue.length = 8;
 484                 var->transp.offset = 24;
 485                 var->transp.length = 8;
 486                 break;
 487         }
 488         var->red.msb_right = var->green.msb_right = var->blue.msb_right =
 489             var->transp.msb_right = 0;
 490         var->grayscale = 0;
 491         var->nonstd = 0;
 492         var->activate = 0;
 493         var->height = var->width = -1;
 494         var->pixclock = 10000;
 495         var->left_margin = var->right_margin = 16;
 496         var->upper_margin = var->lower_margin = 16;
 497         var->hsync_len = var->vsync_len = 8;
 498         var->sync = 0;
 499         var->vmode = FB_VMODE_NONINTERLACED;
 500
 501         /* set offb aperture size for generic probing */
 502         info->apertures = alloc_apertures(1);
 503         if (!info->apertures)
 504                 goto out_aper;
 505         info->apertures->ranges[0].base = address;
 506         info->apertures->ranges[0].size = fix->smem_len;
 507
 508         info->fbops = &offb_ops;
 509         info->screen_base = ioremap(address, fix->smem_len);
 510         info->pseudo_palette = (void *) (info + 1);
 511         info->flags = FBINFO_DEFAULT | FBINFO_MISC_FIRMWARE | foreign_endian;
 512
 513         fb_alloc_cmap(&info->cmap, 256, 0);
 514
 515         if (register_framebuffer(info) < 0)
 516                 goto out_err;
 517
 518         printk(KERN_INFO "fb%d: Open Firmware frame buffer device on %s\n",
 519                info->node, full_name);
 520         return;
 521
 522 out_err:
 523         iounmap(info->screen_base);
 524 out_aper:
 525         iounmap(par->cmap_adr);
 526         par->cmap_adr = NULL;
 527         framebuffer_release(info);
 528         release_mem_region(res_start, res_size);
 529 }
 530
 531
 532 static void __init offb_init_nodriver(struct device_node *dp, int no_real_node)
 533 {
 534         unsigned int len;
 535         int i, width = 640, height = 480, depth = 8, pitch = 640;
 536         unsigned int flags, rsize, addr_prop = 0;
 537         unsigned long max_size = 0;
 538         u64 rstart, address = OF_BAD_ADDR;
 539         const u32 *pp, *addrp, *up;
 540         u64 asize;
 541         int foreign_endian = 0;
 542
 543 #ifdef __BIG_ENDIAN
 544         if (of_get_property(dp, "little-endian", NULL))
 545                 foreign_endian = FBINFO_FOREIGN_ENDIAN;
 546 #else
 547         if (of_get_property(dp, "big-endian", NULL))
 548                 foreign_endian = FBINFO_FOREIGN_ENDIAN;
 549 #endif
 550
 551         pp = of_get_property(dp, "linux,bootx-depth", &len);
 552         if (pp == NULL)
 553                 pp = of_get_property(dp, "depth", &len);
 554         if (pp && len == sizeof(u32))
 555                 depth = *pp;
 556
 557         pp = of_get_property(dp, "linux,bootx-width", &len);
 558         if (pp == NULL)
 559                 pp = of_get_property(dp, "width", &len);
 560         if (pp && len == sizeof(u32))
 561                 width = *pp;
 562
 563         pp = of_get_property(dp, "linux,bootx-height", &len);
 564         if (pp == NULL)
 565                 pp = of_get_property(dp, "height", &len);
 566         if (pp && len == sizeof(u32))
 567                 height = *pp;
 568
 569         pp = of_get_property(dp, "linux,bootx-linebytes", &len);
 570         if (pp == NULL)
 571                 pp = of_get_property(dp, "linebytes", &len);
 572         if (pp && len == sizeof(u32) && (*pp != 0xffffffffu))
 573                 pitch = *pp;
 574         else
 575                 pitch = width * ((depth + 7) / 8);
 576
 577         rsize = (unsigned long)pitch * (unsigned long)height;
 578
 579         /* Ok, now we try to figure out the address of the framebuffer.
 580          *
 581          * Unfortunately, Open Firmware doesn't provide a standard way to do
 582          * so. All we can do is a dodgy heuristic that happens to work in
 583          * practice. On most machines, the "address" property contains what
 584          * we need, though not on Matrox cards found in IBM machines. What I've
 585          * found that appears to give good results is to go through the PCI
 586          * ranges and pick one that is both big enough and if possible encloses
 587          * the "address" property. If none match, we pick the biggest
 588          */
 589         up = of_get_property(dp, "linux,bootx-addr", &len);
 590         if (up == NULL)
 591                 up = of_get_property(dp, "address", &len);
 592         if (up && len == sizeof(u32))
 593                 addr_prop = *up;
 594
 595         /* Hack for when BootX is passing us */
 596         if (no_real_node)
 597                 goto skip_addr;
 598
 599         for (i = 0; (addrp = of_get_address(dp, i, &asize, &flags))
 600                      != NULL; i++) {
 601                 int match_addrp = 0;
 602
 603                 if (!(flags & IORESOURCE_MEM))
 604                         continue;
 605                 if (asize < rsize)
 606                         continue;
 607                 rstart = of_translate_address(dp, addrp);
 608                 if (rstart == OF_BAD_ADDR)
 609                         continue;
 610                 if (addr_prop && (rstart <= addr_prop) &&
 611                     ((rstart + asize) >= (addr_prop + rsize)))
 612                         match_addrp = 1;
 613                 if (match_addrp) {
 614                         address = addr_prop;
 615                         break;
 616                 }
 617                 if (rsize > max_size) {
 618                         max_size = rsize;
 619                         address = OF_BAD_ADDR;
 620                 }
 621
 622                 if (address == OF_BAD_ADDR)
 623                         address = rstart;
 624         }
 625  skip_addr:
 626         if (address == OF_BAD_ADDR && addr_prop)
 627                 address = (u64)addr_prop;
 628         if (address != OF_BAD_ADDR) {
 629                 /* kludge for valkyrie */
 630                 if (strcmp(dp->name, "valkyrie") == 0)
 631                         address += 0x1000;
 632                 offb_init_fb(no_real_node ? "bootx" : dp->name,
 633                              no_real_node ? "display" : dp->full_name,
 634                              width, height, depth, pitch, address,
 635                              foreign_endian, no_real_node ? NULL : dp);
 636         }
 637 }
 638
 639 static int __init offb_init(void)
 640 {
 641         struct device_node *dp = NULL, *boot_disp = NULL;
 642
 643         if (fb_get_options("offb", NULL))
 644                 return -ENODEV;
 645
 646         /* Check if we have a MacOS display without a node spec */
 647         if (of_get_property(of_chosen, "linux,bootx-noscreen", NULL) != NULL) {
 648                 /* The old code tried to work out which node was the MacOS
 649                  * display based on the address. I'm dropping that since the
 650                  * lack of a node spec only happens with old BootX versions
 651                  * (users can update) and with this code, they'll still get
 652                  * a display (just not the palette hacks).
 653                  */
 654                 offb_init_nodriver(of_chosen, 1);
 655         }
 656
 657         for (dp = NULL; (dp = of_find_node_by_type(dp, "display"));) {
 658                 if (of_get_property(dp, "linux,opened", NULL) &&
 659                     of_get_property(dp, "linux,boot-display", NULL)) {
 660                         boot_disp = dp;
 661                         offb_init_nodriver(dp, 0);
 662                 }
 663         }
 664         for (dp = NULL; (dp = of_find_node_by_type(dp, "display"));) {
 665                 if (of_get_property(dp, "linux,opened", NULL) &&
 666                     dp != boot_disp)
 667                         offb_init_nodriver(dp, 0);
 668         }
 669
 670         return 0;
 671 }
 672
 673
 674 module_init(offb_init);
 675 MODULE_LICENSE("GPL");