git.oblomov.eu Git - linux-2.6/blob - drivers/video/acornfb.c

   1 /*
   2  *  linux/drivers/video/acornfb.c
   3  *
   4  *  Copyright (C) 1998-2001 Russell King
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * Frame buffer code for Acorn platforms
  11  *
  12  * NOTE: Most of the modes with X!=640 will disappear shortly.
  13  * NOTE: Startup setting of HS & VS polarity not supported.
  14  *       (do we need to support it if we're coming up in 640x480?)
  15  *
  16  * FIXME: (things broken by the "new improved" FBCON API)
  17  *  - Blanking 8bpp displays with VIDC
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/kernel.h>
  22 #include <linux/errno.h>
  23 #include <linux/string.h>
  24 #include <linux/ctype.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/fb.h>
  28 #include <linux/platform_device.h>
  29 #include <linux/dma-mapping.h>
  30
  31 #include <asm/hardware.h>
  32 #include <asm/io.h>
  33 #include <asm/irq.h>
  34 #include <asm/mach-types.h>
  35 #include <asm/pgtable.h>
  36
  37 #include "acornfb.h"
  38
  39 /*
  40  * VIDC machines can't do 16 or 32BPP modes.
  41  */
  42 #ifdef HAS_VIDC
  43 #undef FBCON_HAS_CFB16
  44 #undef FBCON_HAS_CFB32
  45 #endif
  46
  47 /*
  48  * Default resolution.
  49  * NOTE that it has to be supported in the table towards
  50  * the end of this file.
  51  */
  52 #define DEFAULT_XRES    640
  53 #define DEFAULT_YRES    480
  54 #define DEFAULT_BPP     4
  55
  56 /*
  57  * define this to debug the video mode selection
  58  */
  59 #undef DEBUG_MODE_SELECTION
  60
  61 /*
  62  * Translation from RISC OS monitor types to actual
  63  * HSYNC and VSYNC frequency ranges.  These are
  64  * probably not right, but they're the best info I
  65  * have.  Allow 1% either way on the nominal for TVs.
  66  */
  67 #define NR_MONTYPES     6
  68 static struct fb_monspecs monspecs[NR_MONTYPES] __initdata = {
  69         {       /* TV           */
  70                 .hfmin  = 15469,
  71                 .hfmax  = 15781,
  72                 .vfmin  = 49,
  73                 .vfmax  = 51,
  74         }, {    /* Multi Freq   */
  75                 .hfmin  = 0,
  76                 .hfmax  = 99999,
  77                 .vfmin  = 0,
  78                 .vfmax  = 199,
  79         }, {    /* Hi-res mono  */
  80                 .hfmin  = 58608,
  81                 .hfmax  = 58608,
  82                 .vfmin  = 64,
  83                 .vfmax  = 64,
  84         }, {    /* VGA          */
  85                 .hfmin  = 30000,
  86                 .hfmax  = 70000,
  87                 .vfmin  = 60,
  88                 .vfmax  = 60,
  89         }, {    /* SVGA         */
  90                 .hfmin  = 30000,
  91                 .hfmax  = 70000,
  92                 .vfmin  = 56,
  93                 .vfmax  = 75,
  94         }, {
  95                 .hfmin  = 30000,
  96                 .hfmax  = 70000,
  97                 .vfmin  = 60,
  98                 .vfmax  = 60,
  99         }
 100 };
 101
 102 static struct fb_info fb_info;
 103 static struct acornfb_par current_par;
 104 static struct vidc_timing current_vidc;
 105
 106 extern unsigned int vram_size;  /* set by setup.c */
 107
 108 #ifdef HAS_VIDC
 109
 110 #define MAX_SIZE        480*1024
 111
 112 /* CTL     VIDC Actual
 113  * 24.000  0     8.000
 114  * 25.175  0     8.392
 115  * 36.000  0    12.000
 116  * 24.000  1    12.000
 117  * 25.175  1    12.588
 118  * 24.000  2    16.000
 119  * 25.175  2    16.783
 120  * 36.000  1    18.000
 121  * 24.000  3    24.000
 122  * 36.000  2    24.000
 123  * 25.175  3    25.175
 124  * 36.000  3    36.000
 125  */
 126 struct pixclock {
 127         u_long  min_clock;
 128         u_long  max_clock;
 129         u_int   vidc_ctl;
 130         u_int   vid_ctl;
 131 };
 132
 133 static struct pixclock arc_clocks[] = {
 134         /* we allow +/-1% on these */
 135         { 123750, 126250, VIDC_CTRL_DIV3,   VID_CTL_24MHz },    /*  8.000MHz */
 136         {  82500,  84167, VIDC_CTRL_DIV2,   VID_CTL_24MHz },    /* 12.000MHz */
 137         {  61875,  63125, VIDC_CTRL_DIV1_5, VID_CTL_24MHz },    /* 16.000MHz */
 138         {  41250,  42083, VIDC_CTRL_DIV1,   VID_CTL_24MHz },    /* 24.000MHz */
 139 };
 140
 141 static struct pixclock *
 142 acornfb_valid_pixrate(struct fb_var_screeninfo *var)
 143 {
 144         u_long pixclock = var->pixclock;
 145         u_int i;
 146
 147         if (!var->pixclock)
 148                 return NULL;
 149
 150         for (i = 0; i < ARRAY_SIZE(arc_clocks); i++)
 151                 if (pixclock > arc_clocks[i].min_clock &&
 152                     pixclock < arc_clocks[i].max_clock)
 153                         return arc_clocks + i;
 154
 155         return NULL;
 156 }
 157
 158 /* VIDC Rules:
 159  * hcr  : must be even (interlace, hcr/2 must be even)
 160  * hswr : must be even
 161  * hdsr : must be odd
 162  * hder : must be odd
 163  *
 164  * vcr  : must be odd
 165  * vswr : >= 1
 166  * vdsr : >= 1
 167  * vder : >= vdsr
 168  * if interlaced, then hcr/2 must be even
 169  */
 170 static void
 171 acornfb_set_timing(struct fb_var_screeninfo *var)
 172 {
 173         struct pixclock *pclk;
 174         struct vidc_timing vidc;
 175         u_int horiz_correction;
 176         u_int sync_len, display_start, display_end, cycle;
 177         u_int is_interlaced;
 178         u_int vid_ctl, vidc_ctl;
 179         u_int bandwidth;
 180
 181         memset(&vidc, 0, sizeof(vidc));
 182
 183         pclk = acornfb_valid_pixrate(var);
 184         vidc_ctl = pclk->vidc_ctl;
 185         vid_ctl  = pclk->vid_ctl;
 186
 187         bandwidth = var->pixclock * 8 / var->bits_per_pixel;
 188         /* 25.175, 4bpp = 79.444ns per byte, 317.776ns per word: fifo = 2,6 */
 189         if (bandwidth > 143500)
 190                 vidc_ctl |= VIDC_CTRL_FIFO_3_7;
 191         else if (bandwidth > 71750)
 192                 vidc_ctl |= VIDC_CTRL_FIFO_2_6;
 193         else if (bandwidth > 35875)
 194                 vidc_ctl |= VIDC_CTRL_FIFO_1_5;
 195         else
 196                 vidc_ctl |= VIDC_CTRL_FIFO_0_4;
 197
 198         switch (var->bits_per_pixel) {
 199         case 1:
 200                 horiz_correction = 19;
 201                 vidc_ctl |= VIDC_CTRL_1BPP;
 202                 break;
 203
 204         case 2:
 205                 horiz_correction = 11;
 206                 vidc_ctl |= VIDC_CTRL_2BPP;
 207                 break;
 208
 209         case 4:
 210                 horiz_correction = 7;
 211                 vidc_ctl |= VIDC_CTRL_4BPP;
 212                 break;
 213
 214         default:
 215         case 8:
 216                 horiz_correction = 5;
 217                 vidc_ctl |= VIDC_CTRL_8BPP;
 218                 break;
 219         }
 220
 221         if (var->sync & FB_SYNC_COMP_HIGH_ACT) /* should be FB_SYNC_COMP */
 222                 vidc_ctl |= VIDC_CTRL_CSYNC;
 223         else {
 224                 if (!(var->sync & FB_SYNC_HOR_HIGH_ACT))
 225                         vid_ctl |= VID_CTL_HS_NHSYNC;
 226
 227                 if (!(var->sync & FB_SYNC_VERT_HIGH_ACT))
 228                         vid_ctl |= VID_CTL_VS_NVSYNC;
 229         }
 230
 231         sync_len        = var->hsync_len;
 232         display_start   = sync_len + var->left_margin;
 233         display_end     = display_start + var->xres;
 234         cycle           = display_end + var->right_margin;
 235
 236         /* if interlaced, then hcr/2 must be even */
 237         is_interlaced = (var->vmode & FB_VMODE_MASK) == FB_VMODE_INTERLACED;
 238
 239         if (is_interlaced) {
 240                 vidc_ctl |= VIDC_CTRL_INTERLACE;
 241                 if (cycle & 2) {
 242                         cycle += 2;
 243                         var->right_margin += 2;
 244                 }
 245         }
 246
 247         vidc.h_cycle            = (cycle - 2) / 2;
 248         vidc.h_sync_width       = (sync_len - 2) / 2;
 249         vidc.h_border_start     = (display_start - 1) / 2;
 250         vidc.h_display_start    = (display_start - horiz_correction) / 2;
 251         vidc.h_display_end      = (display_end - horiz_correction) / 2;
 252         vidc.h_border_end       = (display_end - 1) / 2;
 253         vidc.h_interlace        = (vidc.h_cycle + 1) / 2;
 254
 255         sync_len        = var->vsync_len;
 256         display_start   = sync_len + var->upper_margin;
 257         display_end     = display_start + var->yres;
 258         cycle           = display_end + var->lower_margin;
 259
 260         if (is_interlaced)
 261                 cycle = (cycle - 3) / 2;
 262         else
 263                 cycle = cycle - 1;
 264
 265         vidc.v_cycle            = cycle;
 266         vidc.v_sync_width       = sync_len - 1;
 267         vidc.v_border_start     = display_start - 1;
 268         vidc.v_display_start    = vidc.v_border_start;
 269         vidc.v_display_end      = display_end - 1;
 270         vidc.v_border_end       = vidc.v_display_end;
 271
 272         if (machine_is_a5k())
 273                 __raw_writeb(vid_ctl, IOEB_VID_CTL);
 274
 275         if (memcmp(&current_vidc, &vidc, sizeof(vidc))) {
 276                 current_vidc = vidc;
 277
 278                 vidc_writel(0xe0000000 | vidc_ctl);
 279                 vidc_writel(0x80000000 | (vidc.h_cycle << 14));
 280                 vidc_writel(0x84000000 | (vidc.h_sync_width << 14));
 281                 vidc_writel(0x88000000 | (vidc.h_border_start << 14));
 282                 vidc_writel(0x8c000000 | (vidc.h_display_start << 14));
 283                 vidc_writel(0x90000000 | (vidc.h_display_end << 14));
 284                 vidc_writel(0x94000000 | (vidc.h_border_end << 14));
 285                 vidc_writel(0x98000000);
 286                 vidc_writel(0x9c000000 | (vidc.h_interlace << 14));
 287                 vidc_writel(0xa0000000 | (vidc.v_cycle << 14));
 288                 vidc_writel(0xa4000000 | (vidc.v_sync_width << 14));
 289                 vidc_writel(0xa8000000 | (vidc.v_border_start << 14));
 290                 vidc_writel(0xac000000 | (vidc.v_display_start << 14));
 291                 vidc_writel(0xb0000000 | (vidc.v_display_end << 14));
 292                 vidc_writel(0xb4000000 | (vidc.v_border_end << 14));
 293                 vidc_writel(0xb8000000);
 294                 vidc_writel(0xbc000000);
 295         }
 296 #ifdef DEBUG_MODE_SELECTION
 297         printk(KERN_DEBUG "VIDC registers for %dx%dx%d:\n", var->xres,
 298                var->yres, var->bits_per_pixel);
 299         printk(KERN_DEBUG " H-cycle          : %d\n", vidc.h_cycle);
 300         printk(KERN_DEBUG " H-sync-width     : %d\n", vidc.h_sync_width);
 301         printk(KERN_DEBUG " H-border-start   : %d\n", vidc.h_border_start);
 302         printk(KERN_DEBUG " H-display-start  : %d\n", vidc.h_display_start);
 303         printk(KERN_DEBUG " H-display-end    : %d\n", vidc.h_display_end);
 304         printk(KERN_DEBUG " H-border-end     : %d\n", vidc.h_border_end);
 305         printk(KERN_DEBUG " H-interlace      : %d\n", vidc.h_interlace);
 306         printk(KERN_DEBUG " V-cycle          : %d\n", vidc.v_cycle);
 307         printk(KERN_DEBUG " V-sync-width     : %d\n", vidc.v_sync_width);
 308         printk(KERN_DEBUG " V-border-start   : %d\n", vidc.v_border_start);
 309         printk(KERN_DEBUG " V-display-start  : %d\n", vidc.v_display_start);
 310         printk(KERN_DEBUG " V-display-end    : %d\n", vidc.v_display_end);
 311         printk(KERN_DEBUG " V-border-end     : %d\n", vidc.v_border_end);
 312         printk(KERN_DEBUG " VIDC Ctrl (E)    : 0x%08X\n", vidc_ctl);
 313         printk(KERN_DEBUG " IOEB Ctrl        : 0x%08X\n", vid_ctl);
 314 #endif
 315 }
 316
 317 static int
 318 acornfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
 319                   u_int trans, struct fb_info *info)
 320 {
 321         union palette pal;
 322
 323         if (regno >= current_par.palette_size)
 324                 return 1;
 325
 326         pal.p = 0;
 327         pal.vidc.reg   = regno;
 328         pal.vidc.red   = red >> 12;
 329         pal.vidc.green = green >> 12;
 330         pal.vidc.blue  = blue >> 12;
 331
 332         current_par.palette[regno] = pal;
 333
 334         vidc_writel(pal.p);
 335
 336         return 0;
 337 }
 338 #endif
 339
 340 #ifdef HAS_VIDC20
 341 #include <asm/arch/acornfb.h>
 342
 343 #define MAX_SIZE        2*1024*1024
 344
 345 /* VIDC20 has a different set of rules from the VIDC:
 346  *  hcr  : must be multiple of 4
 347  *  hswr : must be even
 348  *  hdsr : must be even
 349  *  hder : must be even
 350  *  vcr  : >= 2, (interlace, must be odd)
 351  *  vswr : >= 1
 352  *  vdsr : >= 1
 353  *  vder : >= vdsr
 354  */
 355 static void acornfb_set_timing(struct fb_info *info)
 356 {
 357         struct fb_var_screeninfo *var = &info->var;
 358         struct vidc_timing vidc;
 359         u_int vcr, fsize;
 360         u_int ext_ctl, dat_ctl;
 361         u_int words_per_line;
 362
 363         memset(&vidc, 0, sizeof(vidc));
 364
 365         vidc.h_sync_width       = var->hsync_len - 8;
 366         vidc.h_border_start     = vidc.h_sync_width + var->left_margin + 8 - 12;
 367         vidc.h_display_start    = vidc.h_border_start + 12 - 18;
 368         vidc.h_display_end      = vidc.h_display_start + var->xres;
 369         vidc.h_border_end       = vidc.h_display_end + 18 - 12;
 370         vidc.h_cycle            = vidc.h_border_end + var->right_margin + 12 - 8;
 371         vidc.h_interlace        = vidc.h_cycle / 2;
 372         vidc.v_sync_width       = var->vsync_len - 1;
 373         vidc.v_border_start     = vidc.v_sync_width + var->upper_margin;
 374         vidc.v_display_start    = vidc.v_border_start;
 375         vidc.v_display_end      = vidc.v_display_start + var->yres;
 376         vidc.v_border_end       = vidc.v_display_end;
 377         vidc.control            = acornfb_default_control();
 378
 379         vcr = var->vsync_len + var->upper_margin + var->yres +
 380               var->lower_margin;
 381
 382         if ((var->vmode & FB_VMODE_MASK) == FB_VMODE_INTERLACED) {
 383                 vidc.v_cycle = (vcr - 3) / 2;
 384                 vidc.control |= VIDC20_CTRL_INT;
 385         } else
 386                 vidc.v_cycle = vcr - 2;
 387
 388         switch (var->bits_per_pixel) {
 389         case  1: vidc.control |= VIDC20_CTRL_1BPP;      break;
 390         case  2: vidc.control |= VIDC20_CTRL_2BPP;      break;
 391         case  4: vidc.control |= VIDC20_CTRL_4BPP;      break;
 392         default:
 393         case  8: vidc.control |= VIDC20_CTRL_8BPP;      break;
 394         case 16: vidc.control |= VIDC20_CTRL_16BPP;     break;
 395         case 32: vidc.control |= VIDC20_CTRL_32BPP;     break;
 396         }
 397
 398         acornfb_vidc20_find_rates(&vidc, var);
 399         fsize = var->vsync_len + var->upper_margin + var->lower_margin - 1;
 400
 401         if (memcmp(&current_vidc, &vidc, sizeof(vidc))) {
 402                 current_vidc = vidc;
 403
 404                 vidc_writel(VIDC20_CTRL| vidc.control);
 405                 vidc_writel(0xd0000000 | vidc.pll_ctl);
 406                 vidc_writel(0x80000000 | vidc.h_cycle);
 407                 vidc_writel(0x81000000 | vidc.h_sync_width);
 408                 vidc_writel(0x82000000 | vidc.h_border_start);
 409                 vidc_writel(0x83000000 | vidc.h_display_start);
 410                 vidc_writel(0x84000000 | vidc.h_display_end);
 411                 vidc_writel(0x85000000 | vidc.h_border_end);
 412                 vidc_writel(0x86000000);
 413                 vidc_writel(0x87000000 | vidc.h_interlace);
 414                 vidc_writel(0x90000000 | vidc.v_cycle);
 415                 vidc_writel(0x91000000 | vidc.v_sync_width);
 416                 vidc_writel(0x92000000 | vidc.v_border_start);
 417                 vidc_writel(0x93000000 | vidc.v_display_start);
 418                 vidc_writel(0x94000000 | vidc.v_display_end);
 419                 vidc_writel(0x95000000 | vidc.v_border_end);
 420                 vidc_writel(0x96000000);
 421                 vidc_writel(0x97000000);
 422         }
 423
 424         iomd_writel(fsize, IOMD_FSIZE);
 425
 426         ext_ctl = acornfb_default_econtrol();
 427
 428         if (var->sync & FB_SYNC_COMP_HIGH_ACT) /* should be FB_SYNC_COMP */
 429                 ext_ctl |= VIDC20_ECTL_HS_NCSYNC | VIDC20_ECTL_VS_NCSYNC;
 430         else {
 431                 if (var->sync & FB_SYNC_HOR_HIGH_ACT)
 432                         ext_ctl |= VIDC20_ECTL_HS_HSYNC;
 433                 else
 434                         ext_ctl |= VIDC20_ECTL_HS_NHSYNC;
 435
 436                 if (var->sync & FB_SYNC_VERT_HIGH_ACT)
 437                         ext_ctl |= VIDC20_ECTL_VS_VSYNC;
 438                 else
 439                         ext_ctl |= VIDC20_ECTL_VS_NVSYNC;
 440         }
 441
 442         vidc_writel(VIDC20_ECTL | ext_ctl);
 443
 444         words_per_line = var->xres * var->bits_per_pixel / 32;
 445
 446         if (current_par.using_vram && info->fix.smem_len == 2048*1024)
 447                 words_per_line /= 2;
 448
 449         /* RiscPC doesn't use the VIDC's VRAM control. */
 450         dat_ctl = VIDC20_DCTL_VRAM_DIS | VIDC20_DCTL_SNA | words_per_line;
 451
 452         /* The data bus width is dependent on both the type
 453          * and amount of video memory.
 454          *     DRAM     32bit low
 455          * 1MB VRAM     32bit
 456          * 2MB VRAM     64bit
 457          */
 458         if (current_par.using_vram && current_par.vram_half_sam == 2048)
 459                 dat_ctl |= VIDC20_DCTL_BUS_D63_0;
 460         else
 461                 dat_ctl |= VIDC20_DCTL_BUS_D31_0;
 462
 463         vidc_writel(VIDC20_DCTL | dat_ctl);
 464
 465 #ifdef DEBUG_MODE_SELECTION
 466         printk(KERN_DEBUG "VIDC registers for %dx%dx%d:\n", var->xres,
 467                var->yres, var->bits_per_pixel);
 468         printk(KERN_DEBUG " H-cycle          : %d\n", vidc.h_cycle);
 469         printk(KERN_DEBUG " H-sync-width     : %d\n", vidc.h_sync_width);
 470         printk(KERN_DEBUG " H-border-start   : %d\n", vidc.h_border_start);
 471         printk(KERN_DEBUG " H-display-start  : %d\n", vidc.h_display_start);
 472         printk(KERN_DEBUG " H-display-end    : %d\n", vidc.h_display_end);
 473         printk(KERN_DEBUG " H-border-end     : %d\n", vidc.h_border_end);
 474         printk(KERN_DEBUG " H-interlace      : %d\n", vidc.h_interlace);
 475         printk(KERN_DEBUG " V-cycle          : %d\n", vidc.v_cycle);
 476         printk(KERN_DEBUG " V-sync-width     : %d\n", vidc.v_sync_width);
 477         printk(KERN_DEBUG " V-border-start   : %d\n", vidc.v_border_start);
 478         printk(KERN_DEBUG " V-display-start  : %d\n", vidc.v_display_start);
 479         printk(KERN_DEBUG " V-display-end    : %d\n", vidc.v_display_end);
 480         printk(KERN_DEBUG " V-border-end     : %d\n", vidc.v_border_end);
 481         printk(KERN_DEBUG " Ext Ctrl  (C)    : 0x%08X\n", ext_ctl);
 482         printk(KERN_DEBUG " PLL Ctrl  (D)    : 0x%08X\n", vidc.pll_ctl);
 483         printk(KERN_DEBUG " Ctrl      (E)    : 0x%08X\n", vidc.control);
 484         printk(KERN_DEBUG " Data Ctrl (F)    : 0x%08X\n", dat_ctl);
 485         printk(KERN_DEBUG " Fsize            : 0x%08X\n", fsize);
 486 #endif
 487 }
 488
 489 /*
 490  * We have to take note of the VIDC20's 16-bit palette here.
 491  * The VIDC20 looks up a 16 bit pixel as follows:
 492  *
 493  *   bits   111111
 494  *          5432109876543210
 495  *   red            ++++++++  (8 bits,  7 to 0)
 496  *  green       ++++++++      (8 bits, 11 to 4)
 497  *   blue   ++++++++          (8 bits, 15 to 8)
 498  *
 499  * We use a pixel which looks like:
 500  *
 501  *   bits   111111
 502  *          5432109876543210
 503  *   red               +++++  (5 bits,  4 to  0)
 504  *  green         +++++       (5 bits,  9 to  5)
 505  *   blue    +++++            (5 bits, 14 to 10)
 506  */
 507 static int
 508 acornfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
 509                   u_int trans, struct fb_info *info)
 510 {
 511         union palette pal;
 512
 513         if (regno >= current_par.palette_size)
 514                 return 1;
 515
 516         if (regno < 16 && info->fix.visual == FB_VISUAL_DIRECTCOLOR) {
 517                 u32 pseudo_val;
 518
 519                 pseudo_val  = regno << info->var.red.offset;
 520                 pseudo_val |= regno << info->var.green.offset;
 521                 pseudo_val |= regno << info->var.blue.offset;
 522
 523                 ((u32 *)info->pseudo_palette)[regno] = pseudo_val;
 524         }
 525
 526         pal.p = 0;
 527         pal.vidc20.red   = red >> 8;
 528         pal.vidc20.green = green >> 8;
 529         pal.vidc20.blue  = blue >> 8;
 530
 531         current_par.palette[regno] = pal;
 532
 533         if (info->var.bits_per_pixel == 16) {
 534                 int i;
 535
 536                 pal.p = 0;
 537                 vidc_writel(0x10000000);
 538                 for (i = 0; i < 256; i += 1) {
 539                         pal.vidc20.red   = current_par.palette[ i       & 31].vidc20.red;
 540                         pal.vidc20.green = current_par.palette[(i >> 1) & 31].vidc20.green;
 541                         pal.vidc20.blue  = current_par.palette[(i >> 2) & 31].vidc20.blue;
 542                         vidc_writel(pal.p);
 543                         /* Palette register pointer auto-increments */
 544                 }
 545         } else {
 546                 vidc_writel(0x10000000 | regno);
 547                 vidc_writel(pal.p);
 548         }
 549
 550         return 0;
 551 }
 552 #endif
 553
 554 /*
 555  * Before selecting the timing parameters, adjust
 556  * the resolution to fit the rules.
 557  */
 558 static int
 559 acornfb_adjust_timing(struct fb_info *info, struct fb_var_screeninfo *var, u_int fontht)
 560 {
 561         u_int font_line_len, sam_size, min_size, size, nr_y;
 562
 563         /* xres must be even */
 564         var->xres = (var->xres + 1) & ~1;
 565
 566         /*
 567          * We don't allow xres_virtual to differ from xres
 568          */
 569         var->xres_virtual = var->xres;
 570         var->xoffset = 0;
 571
 572         if (current_par.using_vram)
 573                 sam_size = current_par.vram_half_sam * 2;
 574         else
 575                 sam_size = 16;
 576
 577         /*
 578          * Now, find a value for yres_virtual which allows
 579          * us to do ywrap scrolling.  The value of
 580          * yres_virtual must be such that the end of the
 581          * displayable frame buffer must be aligned with
 582          * the start of a font line.
 583          */
 584         font_line_len = var->xres * var->bits_per_pixel * fontht / 8;
 585         min_size = var->xres * var->yres * var->bits_per_pixel / 8;
 586
 587         /*
 588          * If minimum screen size is greater than that we have
 589          * available, reject it.
 590          */
 591         if (min_size > info->fix.smem_len)
 592                 return -EINVAL;
 593
 594         /* Find int 'y', such that y * fll == s * sam < maxsize
 595          * y = s * sam / fll; s = maxsize / sam
 596          */
 597         for (size = info->fix.smem_len;
 598              nr_y = size / font_line_len, min_size <= size;
 599              size -= sam_size) {
 600                 if (nr_y * font_line_len == size)
 601                         break;
 602         }
 603         nr_y *= fontht;
 604
 605         if (var->accel_flags & FB_ACCELF_TEXT) {
 606                 if (min_size > size) {
 607                         /*
 608                          * failed, use ypan
 609                          */
 610                         size = info->fix.smem_len;
 611                         var->yres_virtual = size / (font_line_len / fontht);
 612                 } else
 613                         var->yres_virtual = nr_y;
 614         } else if (var->yres_virtual > nr_y)
 615                 var->yres_virtual = nr_y;
 616
 617         current_par.screen_end = info->fix.smem_start + size;
 618
 619         /*
 620          * Fix yres & yoffset if needed.
 621          */
 622         if (var->yres > var->yres_virtual)
 623                 var->yres = var->yres_virtual;
 624
 625         if (var->vmode & FB_VMODE_YWRAP) {
 626                 if (var->yoffset > var->yres_virtual)
 627                         var->yoffset = var->yres_virtual;
 628         } else {
 629                 if (var->yoffset + var->yres > var->yres_virtual)
 630                         var->yoffset = var->yres_virtual - var->yres;
 631         }
 632
 633         /* hsync_len must be even */
 634         var->hsync_len = (var->hsync_len + 1) & ~1;
 635
 636 #ifdef HAS_VIDC
 637         /* left_margin must be odd */
 638         if ((var->left_margin & 1) == 0) {
 639                 var->left_margin -= 1;
 640                 var->right_margin += 1;
 641         }
 642
 643         /* right_margin must be odd */
 644         var->right_margin |= 1;
 645 #elif defined(HAS_VIDC20)
 646         /* left_margin must be even */
 647         if (var->left_margin & 1) {
 648                 var->left_margin += 1;
 649                 var->right_margin -= 1;
 650         }
 651
 652         /* right_margin must be even */
 653         if (var->right_margin & 1)
 654                 var->right_margin += 1;
 655 #endif
 656
 657         if (var->vsync_len < 1)
 658                 var->vsync_len = 1;
 659
 660         return 0;
 661 }
 662
 663 static int
 664 acornfb_validate_timing(struct fb_var_screeninfo *var,
 665                         struct fb_monspecs *monspecs)
 666 {
 667         unsigned long hs, vs;
 668
 669         /*
 670          * hs(Hz) = 10^12 / (pixclock * xtotal)
 671          * vs(Hz) = hs(Hz) / ytotal
 672          *
 673          * No need to do long long divisions or anything
 674          * like that if you factor it correctly
 675          */
 676         hs = 1953125000 / var->pixclock;
 677         hs = hs * 512 /
 678              (var->xres + var->left_margin + var->right_margin + var->hsync_len);
 679         vs = hs /
 680              (var->yres + var->upper_margin + var->lower_margin + var->vsync_len);
 681
 682         return (vs >= monspecs->vfmin && vs <= monspecs->vfmax &&
 683                 hs >= monspecs->hfmin && hs <= monspecs->hfmax) ? 0 : -EINVAL;
 684 }
 685
 686 static inline void
 687 acornfb_update_dma(struct fb_info *info, struct fb_var_screeninfo *var)
 688 {
 689         u_int off = var->yoffset * info->fix.line_length;
 690
 691 #if defined(HAS_MEMC)
 692         memc_write(VDMA_INIT, off >> 2);
 693 #elif defined(HAS_IOMD)
 694         iomd_writel(info->fix.smem_start + off, IOMD_VIDINIT);
 695 #endif
 696 }
 697
 698 static int
 699 acornfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
 700 {
 701         u_int fontht;
 702         int err;
 703
 704         /*
 705          * FIXME: Find the font height
 706          */
 707         fontht = 8;
 708
 709         var->red.msb_right = 0;
 710         var->green.msb_right = 0;
 711         var->blue.msb_right = 0;
 712         var->transp.msb_right = 0;
 713
 714         switch (var->bits_per_pixel) {
 715         case 1: case 2: case 4: case 8:
 716                 var->red.offset    = 0;
 717                 var->red.length    = var->bits_per_pixel;
 718                 var->green         = var->red;
 719                 var->blue          = var->red;
 720                 var->transp.offset = 0;
 721                 var->transp.length = 0;
 722                 break;
 723
 724 #ifdef HAS_VIDC20
 725         case 16:
 726                 var->red.offset    = 0;
 727                 var->red.length    = 5;
 728                 var->green.offset  = 5;
 729                 var->green.length  = 5;
 730                 var->blue.offset   = 10;
 731                 var->blue.length   = 5;
 732                 var->transp.offset = 15;
 733                 var->transp.length = 1;
 734                 break;
 735
 736         case 32:
 737                 var->red.offset    = 0;
 738                 var->red.length    = 8;
 739                 var->green.offset  = 8;
 740                 var->green.length  = 8;
 741                 var->blue.offset   = 16;
 742                 var->blue.length   = 8;
 743                 var->transp.offset = 24;
 744                 var->transp.length = 4;
 745                 break;
 746 #endif
 747         default:
 748                 return -EINVAL;
 749         }
 750
 751         /*
 752          * Check to see if the pixel rate is valid.
 753          */
 754         if (!acornfb_valid_pixrate(var))
 755                 return -EINVAL;
 756
 757         /*
 758          * Validate and adjust the resolution to
 759          * match the video generator hardware.
 760          */
 761         err = acornfb_adjust_timing(info, var, fontht);
 762         if (err)
 763                 return err;
 764
 765         /*
 766          * Validate the timing against the
 767          * monitor hardware.
 768          */
 769         return acornfb_validate_timing(var, &info->monspecs);
 770 }
 771
 772 static int acornfb_set_par(struct fb_info *info)
 773 {
 774         switch (info->var.bits_per_pixel) {
 775         case 1:
 776                 current_par.palette_size = 2;
 777                 info->fix.visual = FB_VISUAL_MONO10;
 778                 break;
 779         case 2:
 780                 current_par.palette_size = 4;
 781                 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
 782                 break;
 783         case 4:
 784                 current_par.palette_size = 16;
 785                 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
 786                 break;
 787         case 8:
 788                 current_par.palette_size = VIDC_PALETTE_SIZE;
 789 #ifdef HAS_VIDC
 790                 info->fix.visual = FB_VISUAL_STATIC_PSEUDOCOLOR;
 791 #else
 792                 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
 793 #endif
 794                 break;
 795 #ifdef HAS_VIDC20
 796         case 16:
 797                 current_par.palette_size = 32;
 798                 info->fix.visual = FB_VISUAL_DIRECTCOLOR;
 799                 break;
 800         case 32:
 801                 current_par.palette_size = VIDC_PALETTE_SIZE;
 802                 info->fix.visual = FB_VISUAL_DIRECTCOLOR;
 803                 break;
 804 #endif
 805         default:
 806                 BUG();
 807         }
 808
 809         info->fix.line_length   = (info->var.xres * info->var.bits_per_pixel) / 8;
 810
 811 #if defined(HAS_MEMC)
 812         {
 813                 unsigned long size = info->fix.smem_len - VDMA_XFERSIZE;
 814
 815                 memc_write(VDMA_START, 0);
 816                 memc_write(VDMA_END, size >> 2);
 817         }
 818 #elif defined(HAS_IOMD)
 819         {
 820                 unsigned long start, size;
 821                 u_int control;
 822
 823                 start = info->fix.smem_start;
 824                 size  = current_par.screen_end;
 825
 826                 if (current_par.using_vram) {
 827                         size -= current_par.vram_half_sam;
 828                         control = DMA_CR_E | (current_par.vram_half_sam / 256);
 829                 } else {
 830                         size -= 16;
 831                         control = DMA_CR_E | DMA_CR_D | 16;
 832                 }
 833
 834                 iomd_writel(start,   IOMD_VIDSTART);
 835                 iomd_writel(size,    IOMD_VIDEND);
 836                 iomd_writel(control, IOMD_VIDCR);
 837         }
 838 #endif
 839
 840         acornfb_update_dma(info, &info->var);
 841         acornfb_set_timing(info);
 842
 843         return 0;
 844 }
 845
 846 static int
 847 acornfb_pan_display(struct fb_var_screeninfo *var, struct fb_info *info)
 848 {
 849         u_int y_bottom = var->yoffset;
 850
 851         if (!(var->vmode & FB_VMODE_YWRAP))
 852                 y_bottom += var->yres;
 853
 854         BUG_ON(y_bottom > var->yres_virtual);
 855
 856         acornfb_update_dma(info, var);
 857
 858         return 0;
 859 }
 860
 861 /*
 862  * Note that we are entered with the kernel locked.
 863  */
 864 static int
 865 acornfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
 866 {
 867         unsigned long off, start;
 868         u32 len;
 869
 870         off = vma->vm_pgoff << PAGE_SHIFT;
 871
 872         start = info->fix.smem_start;
 873         len = PAGE_ALIGN(start & ~PAGE_MASK) + info->fix.smem_len;
 874         start &= PAGE_MASK;
 875         if ((vma->vm_end - vma->vm_start + off) > len)
 876                 return -EINVAL;
 877         off += start;
 878         vma->vm_pgoff = off >> PAGE_SHIFT;
 879
 880         /* This is an IO map - tell maydump to skip this VMA */
 881         vma->vm_flags |= VM_IO;
 882
 883         vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
 884
 885         /*
 886          * Don't alter the page protection flags; we want to keep the area
 887          * cached for better performance.  This does mean that we may miss
 888          * some updates to the screen occasionally, but process switches
 889          * should cause the caches and buffers to be flushed often enough.
 890          */
 891         if (io_remap_pfn_range(vma, vma->vm_start, off >> PAGE_SHIFT,
 892                                 vma->vm_end - vma->vm_start,
 893                                 vma->vm_page_prot))
 894                 return -EAGAIN;
 895         return 0;
 896 }
 897
 898 static struct fb_ops acornfb_ops = {
 899         .owner          = THIS_MODULE,
 900         .fb_check_var   = acornfb_check_var,
 901         .fb_set_par     = acornfb_set_par,
 902         .fb_setcolreg   = acornfb_setcolreg,
 903         .fb_pan_display = acornfb_pan_display,
 904         .fb_fillrect    = cfb_fillrect,
 905         .fb_copyarea    = cfb_copyarea,
 906         .fb_imageblit   = cfb_imageblit,
 907         .fb_mmap        = acornfb_mmap,
 908 };
 909
 910 /*
 911  * Everything after here is initialisation!!!
 912  */
 913 static struct fb_videomode modedb[] __initdata = {
 914         {       /* 320x256 @ 50Hz */
 915                 NULL, 50,  320,  256, 125000,  92,  62,  35, 19,  38, 2,
 916                 FB_SYNC_COMP_HIGH_ACT,
 917                 FB_VMODE_NONINTERLACED
 918         }, {    /* 640x250 @ 50Hz, 15.6 kHz hsync */
 919                 NULL, 50,  640,  250,  62500, 185, 123,  38, 21,  76, 3,
 920                 0,
 921                 FB_VMODE_NONINTERLACED
 922         }, {    /* 640x256 @ 50Hz, 15.6 kHz hsync */
 923                 NULL, 50,  640,  256,  62500, 185, 123,  35, 18,  76, 3,
 924                 0,
 925                 FB_VMODE_NONINTERLACED
 926         }, {    /* 640x512 @ 50Hz, 26.8 kHz hsync */
 927                 NULL, 50,  640,  512,  41667, 113,  87,  18,  1,  56, 3,
 928                 0,
 929                 FB_VMODE_NONINTERLACED
 930         }, {    /* 640x250 @ 70Hz, 31.5 kHz hsync */
 931                 NULL, 70,  640,  250,  39722,  48,  16, 109, 88,  96, 2,
 932                 0,
 933                 FB_VMODE_NONINTERLACED
 934         }, {    /* 640x256 @ 70Hz, 31.5 kHz hsync */
 935                 NULL, 70,  640,  256,  39722,  48,  16, 106, 85,  96, 2,
 936                 0,
 937                 FB_VMODE_NONINTERLACED
 938         }, {    /* 640x352 @ 70Hz, 31.5 kHz hsync */
 939                 NULL, 70,  640,  352,  39722,  48,  16,  58, 37,  96, 2,
 940                 0,
 941                 FB_VMODE_NONINTERLACED
 942         }, {    /* 640x480 @ 60Hz, 31.5 kHz hsync */
 943                 NULL, 60,  640,  480,  39722,  48,  16,  32, 11,  96, 2,
 944                 0,
 945                 FB_VMODE_NONINTERLACED
 946         }, {    /* 800x600 @ 56Hz, 35.2 kHz hsync */
 947                 NULL, 56,  800,  600,  27778, 101,  23,  22,  1, 100, 2,
 948                 0,
 949                 FB_VMODE_NONINTERLACED
 950         }, {    /* 896x352 @ 60Hz, 21.8 kHz hsync */
 951                 NULL, 60,  896,  352,  41667,  59,  27,   9,  0, 118, 3,
 952                 0,
 953                 FB_VMODE_NONINTERLACED
 954         }, {    /* 1024x 768 @ 60Hz, 48.4 kHz hsync */
 955                 NULL, 60, 1024,  768,  15385, 160,  24,  29,  3, 136, 6,
 956                 0,
 957                 FB_VMODE_NONINTERLACED
 958         }, {    /* 1280x1024 @ 60Hz, 63.8 kHz hsync */
 959                 NULL, 60, 1280, 1024,   9090, 186,  96,  38,  1, 160, 3,
 960                 0,
 961                 FB_VMODE_NONINTERLACED
 962         }
 963 };
 964
 965 static struct fb_videomode __initdata
 966 acornfb_default_mode = {
 967         .name =         NULL,
 968         .refresh =      60,
 969         .xres =         640,
 970         .yres =         480,
 971         .pixclock =     39722,
 972         .left_margin =  56,
 973         .right_margin = 16,
 974         .upper_margin = 34,
 975         .lower_margin = 9,
 976         .hsync_len =    88,
 977         .vsync_len =    2,
 978         .sync =         0,
 979         .vmode =        FB_VMODE_NONINTERLACED
 980 };
 981
 982 static void __init acornfb_init_fbinfo(void)
 983 {
 984         static int first = 1;
 985
 986         if (!first)
 987                 return;
 988         first = 0;
 989
 990         fb_info.fbops           = &acornfb_ops;
 991         fb_info.flags           = FBINFO_DEFAULT | FBINFO_HWACCEL_YPAN;
 992         fb_info.pseudo_palette  = current_par.pseudo_palette;
 993
 994         strcpy(fb_info.fix.id, "Acorn");
 995         fb_info.fix.type        = FB_TYPE_PACKED_PIXELS;
 996         fb_info.fix.type_aux    = 0;
 997         fb_info.fix.xpanstep    = 0;
 998         fb_info.fix.ypanstep    = 1;
 999         fb_info.fix.ywrapstep   = 1;
1000         fb_info.fix.line_length = 0;
1001         fb_info.fix.accel       = FB_ACCEL_NONE;
1002
1003         /*
1004          * setup initial parameters
1005          */
1006         memset(&fb_info.var, 0, sizeof(fb_info.var));
1007
1008 #if defined(HAS_VIDC20)
1009         fb_info.var.red.length     = 8;
1010         fb_info.var.transp.length  = 4;
1011 #elif defined(HAS_VIDC)
1012         fb_info.var.red.length     = 4;
1013         fb_info.var.transp.length  = 1;
1014 #endif
1015         fb_info.var.green          = fb_info.var.red;
1016         fb_info.var.blue           = fb_info.var.red;
1017         fb_info.var.nonstd         = 0;
1018         fb_info.var.activate       = FB_ACTIVATE_NOW;
1019         fb_info.var.height         = -1;
1020         fb_info.var.width          = -1;
1021         fb_info.var.vmode          = FB_VMODE_NONINTERLACED;
1022         fb_info.var.accel_flags    = FB_ACCELF_TEXT;
1023
1024         current_par.dram_size      = 0;
1025         current_par.montype        = -1;
1026         current_par.dpms           = 0;
1027 }
1028
1029 /*
1030  * setup acornfb options:
1031  *
1032  *  mon:hmin-hmax:vmin-vmax:dpms:width:height
1033  *      Set monitor parameters:
1034  *              hmin   = horizontal minimum frequency (Hz)
1035  *              hmax   = horizontal maximum frequency (Hz)      (optional)
1036  *              vmin   = vertical minimum frequency (Hz)
1037  *              vmax   = vertical maximum frequency (Hz)        (optional)
1038  *              dpms   = DPMS supported?                        (optional)
1039  *              width  = width of picture in mm.                (optional)
1040  *              height = height of picture in mm.               (optional)
1041  *
1042  * montype:type
1043  *      Set RISC-OS style monitor type:
1044  *              0 (or tv)       - TV frequency
1045  *              1 (or multi)    - Multi frequency
1046  *              2 (or hires)    - Hi-res monochrome
1047  *              3 (or vga)      - VGA
1048  *              4 (or svga)     - SVGA
1049  *              auto, or option missing
1050  *                              - try hardware detect
1051  *
1052  * dram:size
1053  *      Set the amount of DRAM to use for the frame buffer
1054  *      (even if you have VRAM).
1055  *      size can optionally be followed by 'M' or 'K' for
1056  *      MB or KB respectively.
1057  */
1058 static void __init
1059 acornfb_parse_mon(char *opt)
1060 {
1061         char *p = opt;
1062
1063         current_par.montype = -2;
1064
1065         fb_info.monspecs.hfmin = simple_strtoul(p, &p, 0);
1066         if (*p == '-')
1067                 fb_info.monspecs.hfmax = simple_strtoul(p + 1, &p, 0);
1068         else
1069                 fb_info.monspecs.hfmax = fb_info.monspecs.hfmin;
1070
1071         if (*p != ':')
1072                 goto bad;
1073
1074         fb_info.monspecs.vfmin = simple_strtoul(p + 1, &p, 0);
1075         if (*p == '-')
1076                 fb_info.monspecs.vfmax = simple_strtoul(p + 1, &p, 0);
1077         else
1078                 fb_info.monspecs.vfmax = fb_info.monspecs.vfmin;
1079
1080         if (*p != ':')
1081                 goto check_values;
1082
1083         fb_info.monspecs.dpms = simple_strtoul(p + 1, &p, 0);
1084
1085         if (*p != ':')
1086                 goto check_values;
1087
1088         fb_info.var.width = simple_strtoul(p + 1, &p, 0);
1089
1090         if (*p != ':')
1091                 goto check_values;
1092
1093         fb_info.var.height = simple_strtoul(p + 1, NULL, 0);
1094
1095 check_values:
1096         if (fb_info.monspecs.hfmax < fb_info.monspecs.hfmin ||
1097             fb_info.monspecs.vfmax < fb_info.monspecs.vfmin)
1098                 goto bad;
1099         return;
1100
1101 bad:
1102         printk(KERN_ERR "Acornfb: bad monitor settings: %s\n", opt);
1103         current_par.montype = -1;
1104 }
1105
1106 static void __init
1107 acornfb_parse_montype(char *opt)
1108 {
1109         current_par.montype = -2;
1110
1111         if (strncmp(opt, "tv", 2) == 0) {
1112                 opt += 2;
1113                 current_par.montype = 0;
1114         } else if (strncmp(opt, "multi", 5) == 0) {
1115                 opt += 5;
1116                 current_par.montype = 1;
1117         } else if (strncmp(opt, "hires", 5) == 0) {
1118                 opt += 5;
1119                 current_par.montype = 2;
1120         } else if (strncmp(opt, "vga", 3) == 0) {
1121                 opt += 3;
1122                 current_par.montype = 3;
1123         } else if (strncmp(opt, "svga", 4) == 0) {
1124                 opt += 4;
1125                 current_par.montype = 4;
1126         } else if (strncmp(opt, "auto", 4) == 0) {
1127                 opt += 4;
1128                 current_par.montype = -1;
1129         } else if (isdigit(*opt))
1130                 current_par.montype = simple_strtoul(opt, &opt, 0);
1131
1132         if (current_par.montype == -2 ||
1133             current_par.montype > NR_MONTYPES) {
1134                 printk(KERN_ERR "acornfb: unknown monitor type: %s\n",
1135                         opt);
1136                 current_par.montype = -1;
1137         } else
1138         if (opt && *opt) {
1139                 if (strcmp(opt, ",dpms") == 0)
1140                         current_par.dpms = 1;
1141                 else
1142                         printk(KERN_ERR
1143                                "acornfb: unknown monitor option: %s\n",
1144                                opt);
1145         }
1146 }
1147
1148 static void __init
1149 acornfb_parse_dram(char *opt)
1150 {
1151         unsigned int size;
1152
1153         size = simple_strtoul(opt, &opt, 0);
1154
1155         if (opt) {
1156                 switch (*opt) {
1157                 case 'M':
1158                 case 'm':
1159                         size *= 1024;
1160                 case 'K':
1161                 case 'k':
1162                         size *= 1024;
1163                 default:
1164                         break;
1165                 }
1166         }
1167
1168         current_par.dram_size = size;
1169 }
1170
1171 static struct options {
1172         char *name;
1173         void (*parse)(char *opt);
1174 } opt_table[] __initdata = {
1175         { "mon",     acornfb_parse_mon     },
1176         { "montype", acornfb_parse_montype },
1177         { "dram",    acornfb_parse_dram    },
1178         { NULL, NULL }
1179 };
1180
1181 int __init
1182 acornfb_setup(char *options)
1183 {
1184         struct options *optp;
1185         char *opt;
1186
1187         if (!options || !*options)
1188                 return 0;
1189
1190         acornfb_init_fbinfo();
1191
1192         while ((opt = strsep(&options, ",")) != NULL) {
1193                 if (!*opt)
1194                         continue;
1195
1196                 for (optp = opt_table; optp->name; optp++) {
1197                         int optlen;
1198
1199                         optlen = strlen(optp->name);
1200
1201                         if (strncmp(opt, optp->name, optlen) == 0 &&
1202                             opt[optlen] == ':') {
1203                                 optp->parse(opt + optlen + 1);
1204                                 break;
1205                         }
1206                 }
1207
1208                 if (!optp->name)
1209                         printk(KERN_ERR "acornfb: unknown parameter: %s\n",
1210                                opt);
1211         }
1212         return 0;
1213 }
1214
1215 /*
1216  * Detect type of monitor connected
1217  *  For now, we just assume SVGA
1218  */
1219 static int __init
1220 acornfb_detect_monitortype(void)
1221 {
1222         return 4;
1223 }
1224
1225 /*
1226  * This enables the unused memory to be freed on older Acorn machines.
1227  * We are freeing memory on behalf of the architecture initialisation
1228  * code here.
1229  */
1230 static inline void
1231 free_unused_pages(unsigned int virtual_start, unsigned int virtual_end)
1232 {
1233         int mb_freed = 0;
1234
1235         /*
1236          * Align addresses
1237          */
1238         virtual_start = PAGE_ALIGN(virtual_start);
1239         virtual_end = PAGE_ALIGN(virtual_end);
1240
1241         while (virtual_start < virtual_end) {
1242                 struct page *page;
1243
1244                 /*
1245                  * Clear page reserved bit,
1246                  * set count to 1, and free
1247                  * the page.
1248                  */
1249                 page = virt_to_page(virtual_start);
1250                 ClearPageReserved(page);
1251                 init_page_count(page);
1252                 free_page(virtual_start);
1253
1254                 virtual_start += PAGE_SIZE;
1255                 mb_freed += PAGE_SIZE / 1024;
1256         }
1257
1258         printk("acornfb: freed %dK memory\n", mb_freed);
1259 }
1260
1261 static int __init acornfb_probe(struct platform_device *dev)
1262 {
1263         unsigned long size;
1264         u_int h_sync, v_sync;
1265         int rc, i;
1266         char *option = NULL;
1267
1268         if (fb_get_options("acornfb", &option))
1269                 return -ENODEV;
1270         acornfb_setup(option);
1271
1272         acornfb_init_fbinfo();
1273
1274         current_par.dev = &dev->dev;
1275
1276         if (current_par.montype == -1)
1277                 current_par.montype = acornfb_detect_monitortype();
1278
1279         if (current_par.montype == -1 || current_par.montype > NR_MONTYPES)
1280                 current_par.montype = 4;
1281
1282         if (current_par.montype >= 0) {
1283                 fb_info.monspecs = monspecs[current_par.montype];
1284                 fb_info.monspecs.dpms = current_par.dpms;
1285         }
1286
1287         /*
1288          * Try to select a suitable default mode
1289          */
1290         for (i = 0; i < ARRAY_SIZE(modedb); i++) {
1291                 unsigned long hs;
1292
1293                 hs = modedb[i].refresh *
1294                      (modedb[i].yres + modedb[i].upper_margin +
1295                       modedb[i].lower_margin + modedb[i].vsync_len);
1296                 if (modedb[i].xres == DEFAULT_XRES &&
1297                     modedb[i].yres == DEFAULT_YRES &&
1298                     modedb[i].refresh >= fb_info.monspecs.vfmin &&
1299                     modedb[i].refresh <= fb_info.monspecs.vfmax &&
1300                     hs                >= fb_info.monspecs.hfmin &&
1301                     hs                <= fb_info.monspecs.hfmax) {
1302                         acornfb_default_mode = modedb[i];
1303                         break;
1304                 }
1305         }
1306
1307         fb_info.screen_base    = (char *)SCREEN_BASE;
1308         fb_info.fix.smem_start = SCREEN_START;
1309         current_par.using_vram = 0;
1310
1311         /*
1312          * If vram_size is set, we are using VRAM in
1313          * a Risc PC.  However, if the user has specified
1314          * an amount of DRAM then use that instead.
1315          */
1316         if (vram_size && !current_par.dram_size) {
1317                 size = vram_size;
1318                 current_par.vram_half_sam = vram_size / 1024;
1319                 current_par.using_vram = 1;
1320         } else if (current_par.dram_size)
1321                 size = current_par.dram_size;
1322         else
1323                 size = MAX_SIZE;
1324
1325         /*
1326          * Limit maximum screen size.
1327          */
1328         if (size > MAX_SIZE)
1329                 size = MAX_SIZE;
1330
1331         size = PAGE_ALIGN(size);
1332
1333 #if defined(HAS_VIDC20)
1334         if (!current_par.using_vram) {
1335                 dma_addr_t handle;
1336                 void *base;
1337
1338                 /*
1339                  * RiscPC needs to allocate the DRAM memory
1340                  * for the framebuffer if we are not using
1341                  * VRAM.
1342                  */
1343                 base = dma_alloc_writecombine(current_par.dev, size, &handle,
1344                                               GFP_KERNEL);
1345                 if (base == NULL) {
1346                         printk(KERN_ERR "acornfb: unable to allocate screen "
1347                                "memory\n");
1348                         return -ENOMEM;
1349                 }
1350
1351                 fb_info.screen_base = base;
1352                 fb_info.fix.smem_start = handle;
1353         }
1354 #endif
1355 #if defined(HAS_VIDC)
1356         /*
1357          * Archimedes/A5000 machines use a fixed address for their
1358          * framebuffers.  Free unused pages
1359          */
1360         free_unused_pages(PAGE_OFFSET + size, PAGE_OFFSET + MAX_SIZE);
1361 #endif
1362
1363         fb_info.fix.smem_len = size;
1364         current_par.palette_size   = VIDC_PALETTE_SIZE;
1365
1366         /*
1367          * Lookup the timing for this resolution.  If we can't
1368          * find it, then we can't restore it if we change
1369          * the resolution, so we disable this feature.
1370          */
1371         do {
1372                 rc = fb_find_mode(&fb_info.var, &fb_info, NULL, modedb,
1373                                  ARRAY_SIZE(modedb),
1374                                  &acornfb_default_mode, DEFAULT_BPP);
1375                 /*
1376                  * If we found an exact match, all ok.
1377                  */
1378                 if (rc == 1)
1379                         break;
1380
1381                 rc = fb_find_mode(&fb_info.var, &fb_info, NULL, NULL, 0,
1382                                   &acornfb_default_mode, DEFAULT_BPP);
1383                 /*
1384                  * If we found an exact match, all ok.
1385                  */
1386                 if (rc == 1)
1387                         break;
1388
1389                 rc = fb_find_mode(&fb_info.var, &fb_info, NULL, modedb,
1390                                  ARRAY_SIZE(modedb),
1391                                  &acornfb_default_mode, DEFAULT_BPP);
1392                 if (rc)
1393                         break;
1394
1395                 rc = fb_find_mode(&fb_info.var, &fb_info, NULL, NULL, 0,
1396                                   &acornfb_default_mode, DEFAULT_BPP);
1397         } while (0);
1398
1399         /*
1400          * If we didn't find an exact match, try the
1401          * generic database.
1402          */
1403         if (rc == 0) {
1404                 printk("Acornfb: no valid mode found\n");
1405                 return -EINVAL;
1406         }
1407
1408         h_sync = 1953125000 / fb_info.var.pixclock;
1409         h_sync = h_sync * 512 / (fb_info.var.xres + fb_info.var.left_margin +
1410                  fb_info.var.right_margin + fb_info.var.hsync_len);
1411         v_sync = h_sync / (fb_info.var.yres + fb_info.var.upper_margin +
1412                  fb_info.var.lower_margin + fb_info.var.vsync_len);
1413
1414         printk(KERN_INFO "Acornfb: %dkB %cRAM, %s, using %dx%d, "
1415                 "%d.%03dkHz, %dHz\n",
1416                 fb_info.fix.smem_len / 1024,
1417                 current_par.using_vram ? 'V' : 'D',
1418                 VIDC_NAME, fb_info.var.xres, fb_info.var.yres,
1419                 h_sync / 1000, h_sync % 1000, v_sync);
1420
1421         printk(KERN_INFO "Acornfb: Monitor: %d.%03d-%d.%03dkHz, %d-%dHz%s\n",
1422                 fb_info.monspecs.hfmin / 1000, fb_info.monspecs.hfmin % 1000,
1423                 fb_info.monspecs.hfmax / 1000, fb_info.monspecs.hfmax % 1000,
1424                 fb_info.monspecs.vfmin, fb_info.monspecs.vfmax,
1425                 fb_info.monspecs.dpms ? ", DPMS" : "");
1426
1427         if (fb_set_var(&fb_info, &fb_info.var))
1428                 printk(KERN_ERR "Acornfb: unable to set display parameters\n");
1429
1430         if (register_framebuffer(&fb_info) < 0)
1431                 return -EINVAL;
1432         return 0;
1433 }
1434
1435 static struct platform_driver acornfb_driver = {
1436         .probe  = acornfb_probe,
1437         .driver = {
1438                 .name   = "acornfb",
1439         },
1440 };
1441
1442 static int __init acornfb_init(void)
1443 {
1444         return platform_driver_register(&acornfb_driver);
1445 }
1446
1447 module_init(acornfb_init);
1448
1449 MODULE_AUTHOR("Russell King");
1450 MODULE_DESCRIPTION("VIDC 1/1a/20 framebuffer driver");
1451 MODULE_LICENSE("GPL");