firmware/target/arm/ipod/video/lcd-video.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * LCD driver for iPod Video
  11  *
  12  * Based on code from the ipodlinux project - http://ipodlinux.org/
  13  * Adapted for Rockbox in December 2005
  14  *
  15  * Original file: linux/arch/armnommu/mach-ipod/fb.c
  16  *
  17  * Copyright (c) 2003-2005 Bernard Leach (leachbj@bouncycastle.org)
  18  *
  19  * This program is free software; you can redistribute it and/or
  20  * modify it under the terms of the GNU General Public License
  21  * as published by the Free Software Foundation; either version 2
  22  * of the License, or (at your option) any later version.
  23  *
  24  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  25  * KIND, either express or implied.
  26  *
  27  ****************************************************************************/
  28 #include "config.h"
  29 #include "cpu.h"
  30 #include "lcd.h"
  31 #include "kernel.h"
  32 #include "system.h"
  33 #ifdef HAVE_LCD_SLEEP
  34 /* Included only for lcd_awake() prototype */
  35 #include "backlight-target.h"
  36 #endif
  37
  38 /* The BCM bus width is 16 bits. But since the low address bits aren't decoded
  39  * by the chip (the 3 BCM address bits are mapped to address bits 16..18 of the
  40  * PP5022), writing 32 bits (and even more, using 'stmia') at once works. */
  41 #define BCM_DATA      (*(volatile unsigned short*)(0x30000000))
  42 #define BCM_DATA32    (*(volatile unsigned long *)(0x30000000))
  43 #define BCM_WR_ADDR   (*(volatile unsigned short*)(0x30010000))
  44 #define BCM_WR_ADDR32 (*(volatile unsigned long *)(0x30010000))
  45 #define BCM_RD_ADDR   (*(volatile unsigned short*)(0x30020000))
  46 #define BCM_RD_ADDR32 (*(volatile unsigned long *)(0x30020000))
  47 #define BCM_CONTROL   (*(volatile unsigned short*)(0x30030000))
  48
  49 #define BCM_ALT_DATA      (*(volatile unsigned short*)(0x30040000))
  50 #define BCM_ALT_DATA32    (*(volatile unsigned long *)(0x30040000))
  51 #define BCM_ALT_WR_ADDR   (*(volatile unsigned short*)(0x30050000))
  52 #define BCM_ALT_WR_ADDR32 (*(volatile unsigned long *)(0x30050000))
  53 #define BCM_ALT_RD_ADDR   (*(volatile unsigned short*)(0x30060000))
  54 #define BCM_ALT_RD_ADDR32 (*(volatile unsigned long *)(0x30060000))
  55 #define BCM_ALT_CONTROL   (*(volatile unsigned short*)(0x30070000))
  56
  57 /* Time until the BCM is considered stalled and will be re-kicked.
  58  * Must be guaranteed to be >~ 20ms. */
  59 #define BCM_UPDATE_TIMEOUT (HZ/20)
  60
  61 /* Addresses within BCM */
  62 #define BCMA_SRAM_BASE   0
  63 #define BCMA_COMMAND     0x1F8
  64 #define BCMA_STATUS      0x1FC
  65 #define BCMA_CMDPARAM    0xE0000    /* Parameters/data for commands */
  66 #define BCMA_SDRAM_BASE  0xC0000000
  67 #define BCMA_TV_FB       0xC0000000 /* TV out framebuffer */
  68 #define BCMA_TV_BMPDATA  0xC0200000 /* BMP data for TV out functions */
  69
  70 /* BCM commands.  Write them to BCMA_COMMAND.  Note BCM_CMD encoding. */
  71 #define BCM_CMD(x) ((~((unsigned long)x) << 16) | ((unsigned long)x))
  72 #define BCMCMD_LCD_UPDATE     BCM_CMD(0)
  73 /* Execute "M25 Diagnostics".  Status displayed on LCD.  Takes <40s */
  74 #define BCMCMD_SELFTEST       BCM_CMD(1)
  75 #define BCMCMD_TV_PALBMP      BCM_CMD(2)
  76 #define BCMCMD_TV_NTSCBMP     BCM_CMD(3)
  77 /* BCM_CMD(4) may be another TV-related command */
  78 /* The following might do more depending on word at 0xE00000 */
  79 #define BCMCMD_LCD_UPDATERECT BCM_CMD(5)
  80 #define BCMCMD_LCD_SLEEP      BCM_CMD(8)
  81 /* BCM_CMD(12) involved in shutdown */
  82 /* Macrovision analog copy prevention is on by default on TV output.
  83    Execute this command after enabling TV out to turn it off.
  84  */
  85 #define BCMCMD_TV_MVOFF       BCM_CMD(14)
  86
  87 enum lcd_status {
  88     LCD_IDLE,
  89     LCD_INITIAL,
  90     LCD_NEED_UPDATE,
  91     LCD_UPDATING
  92 };
  93
  94 struct {
  95     long update_timeout;
  96     enum lcd_status state;
  97     bool blocked;
  98 #if NUM_CORES > 1
  99     struct corelock cl;   /* inter-core sync */
 100 #endif
 101 #ifdef HAVE_LCD_SLEEP
 102     bool display_on;
 103 #endif
 104 } lcd_state IBSS_ATTR;
 105
 106 #ifdef HAVE_LCD_SLEEP
 107 static long bcm_off_wait;
 108 const fb_data *flash_vmcs_offset;
 109 unsigned flash_vmcs_length;
 110 /* This mutex exists because enabling the backlight by changing a setting
 111    will cause multiple concurrent lcd_wake() calls.
 112  */
 113 static struct mutex lcdstate_lock SHAREDBSS_ATTR;
 114
 115 #define ROM_BASE        0x20000000
 116 #define ROM_ID(a,b,c,d) (unsigned int)(  ((unsigned int)(d))        | \
 117                                         (((unsigned int)(c)) << 8)  | \
 118                                         (((unsigned int)(b)) << 16) | \
 119                                         (((unsigned int)(a)) << 24) )
 120
 121 /* Get address and length of iPod flash section.
 122    Based on part of FS#6721.  This may belong elsewhere.
 123    (BCM initialization uploads the vmcs section to the BCM.)
 124  */
 125 bool flash_get_section(const unsigned int imageid,
 126                        void **offset,
 127                        unsigned int *length)
 128 {
 129     unsigned long *p = (unsigned long*)(ROM_BASE + 0xffe00);
 130     unsigned char *csp, *csend;
 131     unsigned long checksum;
 132
 133     /* Find the image in the directory */
 134     while (1) {
 135         if (p[0] != ROM_ID('f','l','s','h'))
 136             return false;
 137         if (p[1] == imageid)
 138             break;
 139         p += 10;
 140     }
 141
 142     *offset = (void *)(ROM_BASE + p[3]);
 143     *length = p[4];
 144
 145     /* Verify checksum.  Probably unnecessary, but it's fast. */
 146     checksum = 0;
 147     csend = (unsigned char *)(ROM_BASE + p[3] + p[4]);
 148     for(csp = (unsigned char *)(ROM_BASE + p[3]); csp < csend; csp++) {
 149         checksum += *csp;
 150     }
 151
 152     return checksum == p[7];
 153 }
 154 #endif /* HAVE_LCD_SLEEP */
 155
 156 static inline void bcm_write_addr(unsigned address)
 157 {
 158     BCM_WR_ADDR32 = address;       /* write destination address */
 159
 160     while (!(BCM_CONTROL & 0x2));  /* wait for it to be write ready */
 161 }
 162
 163 static inline void bcm_write32(unsigned address, unsigned value)
 164 {
 165
 166     bcm_write_addr(address);       /* set destination address */
 167
 168     BCM_DATA32 = value;            /* write value */
 169 }
 170
 171 static inline unsigned bcm_read32(unsigned address)
 172 {
 173     while (!(BCM_RD_ADDR & 1));
 174
 175     BCM_RD_ADDR32 = address;       /* write source address */
 176
 177     while (!(BCM_CONTROL & 0x10)); /* wait for it to be read ready */
 178
 179     return BCM_DATA32;             /* read value */
 180 }
 181
 182 #ifndef BOOTLOADER
 183 static void lcd_tick(void)
 184 {
 185     /* No core level interrupt mask - already in interrupt context */
 186 #if NUM_CORES > 1
 187     corelock_lock(&lcd_state.cl);
 188 #endif
 189
 190     if (!lcd_state.blocked && lcd_state.state >= LCD_NEED_UPDATE)
 191     {
 192         unsigned data = bcm_read32(BCMA_COMMAND);
 193         bool bcm_is_busy = (data == BCMCMD_LCD_UPDATE || data == 0xFFFF);
 194
 195         if (((lcd_state.state == LCD_NEED_UPDATE) && !bcm_is_busy)
 196             /* Update requested and BCM is no longer busy. */
 197          || (TIME_AFTER(current_tick, lcd_state.update_timeout) && bcm_is_busy))
 198             /* BCM still busy after timeout, i.e. stalled. */
 199         {
 200             bcm_write32(BCMA_COMMAND, BCMCMD_LCD_UPDATE);  /* Kick off update */
 201             BCM_CONTROL = 0x31;
 202             lcd_state.update_timeout = current_tick + BCM_UPDATE_TIMEOUT;
 203             lcd_state.state = LCD_UPDATING;
 204         }
 205         else if ((lcd_state.state == LCD_UPDATING) && !bcm_is_busy)
 206         {
 207             /* Update finished properly and no new update pending. */
 208             lcd_state.state = LCD_IDLE;
 209         }
 210     }
 211 #if NUM_CORES > 1
 212     corelock_unlock(&lcd_state.cl);
 213 #endif
 214 }
 215
 216 static inline void lcd_block_tick(void)
 217 {
 218     int oldlevel = disable_irq_save();
 219
 220 #if NUM_CORES > 1
 221     corelock_lock(&lcd_state.cl);
 222     lcd_state.blocked = true;
 223     corelock_unlock(&lcd_state.cl);
 224 #else
 225     lcd_state.blocked = true;
 226 #endif
 227     restore_irq(oldlevel);
 228 }
 229
 230 static void lcd_unblock_and_update(void)
 231 {
 232     unsigned data;
 233     bool bcm_is_busy;
 234     int oldlevel = disable_irq_save();
 235
 236 #if NUM_CORES > 1
 237     corelock_lock(&lcd_state.cl);
 238 #endif
 239     data = bcm_read32(BCMA_COMMAND);
 240     bcm_is_busy = (data == BCMCMD_LCD_UPDATE || data == 0xFFFF);
 241
 242     if (!bcm_is_busy || (lcd_state.state == LCD_INITIAL) ||
 243         TIME_AFTER(current_tick, lcd_state.update_timeout))
 244     {
 245         bcm_write32(BCMA_COMMAND, BCMCMD_LCD_UPDATE);  /* Kick off update */
 246         BCM_CONTROL = 0x31;
 247         lcd_state.update_timeout = current_tick + BCM_UPDATE_TIMEOUT;
 248         lcd_state.state = LCD_UPDATING;
 249     }
 250     else
 251     {
 252          lcd_state.state = LCD_NEED_UPDATE; /* Post update request */
 253     }
 254     lcd_state.blocked = false;
 255
 256 #if NUM_CORES > 1
 257     corelock_unlock(&lcd_state.cl);
 258 #endif
 259     restore_irq(oldlevel);
 260 }
 261
 262 #else /* BOOTLOADER */
 263
 264 #define lcd_block_tick()
 265
 266 static void lcd_unblock_and_update(void)
 267 {
 268     unsigned data;
 269
 270     if (lcd_state.state != LCD_INITIAL)
 271     {
 272         data = bcm_read32(BCMA_COMMAND);
 273         while (data == BCMCMD_LCD_UPDATE || data == 0xFFFF)
 274         {
 275             yield();
 276             data = bcm_read32(BCMA_COMMAND);
 277         }
 278     }
 279     bcm_write32(BCMA_COMMAND, BCMCMD_LCD_UPDATE);  /* Kick off update */
 280     BCM_CONTROL = 0x31;
 281     lcd_state.state = LCD_IDLE;
 282 }
 283 #endif /* BOOTLOADER */
 284
 285 /*** hardware configuration ***/
 286
 287 void lcd_set_contrast(int val)
 288 {
 289   /* TODO: Implement lcd_set_contrast() */
 290   (void)val;
 291 }
 292
 293 void lcd_set_invert_display(bool yesno)
 294 {
 295   /* TODO: Implement lcd_set_invert_display() */
 296   (void)yesno;
 297 }
 298
 299 /* turn the display upside down (call lcd_update() afterwards) */
 300 void lcd_set_flip(bool yesno)
 301 {
 302   /* TODO: Implement lcd_set_flip() */
 303   (void)yesno;
 304 }
 305
 306 /* LCD init */
 307 void lcd_init_device(void)
 308 {
 309     /* These port initializations are supposed to be done when initializing
 310        the BCM.  None of it is changed when shutting down the BCM.
 311      */
 312     GPO32_ENABLE |= 0x4000;
 313     /* GPO32_VAL & 0x8000 may supply power for BCM sleep state */
 314     GPO32_ENABLE |= 0x8000;
 315     GPO32_VAL &= ~0x8000;
 316     GPIO_CLEAR_BITWISE(GPIOC_ENABLE, 0x80);
 317     /* This pin is used for BCM interrupts */
 318     GPIOC_ENABLE |= 0x40;
 319     GPIOC_OUTPUT_EN &= ~0x40;
 320     GPO32_ENABLE &= ~1;
 321
 322     lcd_state.blocked = false;
 323     lcd_state.state = LCD_INITIAL;
 324 #ifndef BOOTLOADER
 325 #if NUM_CORES > 1
 326     corelock_init(&lcd_state.cl);
 327 #endif
 328 #ifdef HAVE_LCD_SLEEP
 329     lcd_state.display_on = true;    /* Code in flash turned it on */
 330     if (!flash_get_section(ROM_ID('v', 'm', 'c', 's'),
 331                            (void **)(&flash_vmcs_offset), &flash_vmcs_length))
 332         /* BCM cannot be shut down because firmware wasn't found */
 333         flash_vmcs_length = 0;
 334     else {
 335         /* lcd_write_data needs an even number of 16 bit values */
 336         flash_vmcs_length = ((flash_vmcs_length + 3) >> 1) & ~1;
 337     }
 338     mutex_init(&lcdstate_lock);
 339 #endif
 340     tick_add_task(&lcd_tick);
 341 #endif /* !BOOTLOADER */
 342 }
 343
 344 /*** update functions ***/
 345
 346 /* Update a fraction of the display. */
 347 void lcd_update_rect(int x, int y, int width, int height)
 348 {
 349     const fb_data *addr;
 350     unsigned bcmaddr;
 351
 352 #ifdef HAVE_LCD_SLEEP
 353     if (!lcd_state.display_on)
 354         return;
 355 #endif
 356
 357     if (x + width >= LCD_WIDTH)
 358         width = LCD_WIDTH - x;
 359     if (y + height >= LCD_HEIGHT)
 360         height = LCD_HEIGHT - y;
 361
 362     if ((width <= 0) || (height <= 0))
 363         return; /* Nothing left to do. */
 364
 365     /* Ensure x and width are both even. The BCM doesn't like small unaligned
 366      * writes and would just ignore them. */
 367     width = (width + (x & 1) + 1) & ~1;
 368     x &= ~1;
 369
 370     /* Prevent the tick from triggering BCM updates while we're writing. */
 371     lcd_block_tick();
 372
 373     addr = &lcd_framebuffer[y][x];
 374     bcmaddr = BCMA_CMDPARAM + (LCD_WIDTH*2) * y + (x << 1);
 375
 376     if (width == LCD_WIDTH)
 377     {
 378         bcm_write_addr(bcmaddr);
 379         lcd_write_data(addr, width * height);
 380     }
 381     else
 382     {
 383         do
 384         {
 385             bcm_write_addr(bcmaddr);
 386             bcmaddr += (LCD_WIDTH*2);
 387             lcd_write_data(addr, width);
 388             addr += LCD_WIDTH;
 389         }
 390         while (--height > 0);
 391     }
 392     lcd_unblock_and_update();
 393 }
 394
 395 /* Update the display.
 396    This must be called after all other LCD functions that change the display. */
 397 void lcd_update(void)
 398 {
 399     lcd_update_rect(0, 0, LCD_WIDTH, LCD_HEIGHT);
 400 }
 401
 402 /* Line write helper function for lcd_yuv_blit. Writes two lines of yuv420. */
 403 extern void lcd_write_yuv420_lines(unsigned char const * const src[3],
 404                                    unsigned bcmaddr,
 405                                    int width,
 406                                    int stride);
 407
 408 /* Performance function to blit a YUV bitmap directly to the LCD */
 409 void lcd_blit_yuv(unsigned char * const src[3],
 410                   int src_x, int src_y, int stride,
 411                   int x, int y, int width, int height)
 412 {
 413     unsigned bcmaddr;
 414     off_t z;
 415     unsigned char const * yuv_src[3];
 416
 417 #ifdef HAVE_LCD_SLEEP
 418     if (!lcd_state.display_on)
 419         return;
 420 #endif
 421
 422     /* Sorry, but width and height must be >= 2 or else */
 423     width &= ~1;
 424
 425     z = stride * src_y;
 426     yuv_src[0] = src[0] + z + src_x;
 427     yuv_src[1] = src[1] + (z >> 2) + (src_x >> 1);
 428     yuv_src[2] = src[2] + (yuv_src[1] - src[1]);
 429
 430     /* Prevent the tick from triggering BCM updates while we're writing. */
 431     lcd_block_tick();
 432
 433     bcmaddr = BCMA_CMDPARAM + (LCD_WIDTH*2) * y + (x << 1);
 434     height >>= 1;
 435
 436     do
 437     {
 438         lcd_write_yuv420_lines(yuv_src, bcmaddr, width, stride);
 439         bcmaddr += (LCD_WIDTH*4);  /* Skip up two lines */
 440         yuv_src[0] += stride << 1;
 441         yuv_src[1] += stride >> 1; /* Skip down one chroma line */
 442         yuv_src[2] += stride >> 1;
 443     }
 444     while (--height > 0);
 445
 446     lcd_unblock_and_update();
 447 }
 448
 449 #ifdef HAVE_LCD_SLEEP
 450 /* Executes a BCM command immediately and waits for it to complete.
 451    Other BCM commands (eg. LCD updates or lcd_tick) must not interfere.
 452  */
 453 static void bcm_command(unsigned cmd) {
 454     unsigned status;
 455
 456     bcm_write32(BCMA_COMMAND,  cmd);
 457
 458     BCM_CONTROL = 0x31;
 459
 460     while (1) {
 461         status = bcm_read32(BCMA_COMMAND);
 462         if (status != cmd && status != 0xFFFF)
 463             break;
 464         yield();
 465     }
 466 }
 467
 468 void bcm_powerdown(void)
 469 {
 470     bcm_write32(0x10001400, bcm_read32(0x10001400) & ~0xF0);
 471
 472     /* Blanks the LCD and decreases power consumption
 473        below what clearing the LCD would achieve.
 474        Executing an LCD update command wakes it.
 475      */
 476     bcm_command(BCMCMD_LCD_SLEEP);
 477
 478     /* Not sure if this does anything */
 479     bcm_command(BCM_CMD(0xC));
 480
 481     /* Further cuts power use, probably by powering down BCM.
 482        After this point, BCM needs to be bootstrapped
 483      */
 484     GPO32_VAL &= ~0x4000;
 485 }
 486
 487 /* Data written to BCM_CONTROL and BCM_ALT_CONTROL */
 488 const unsigned char bcm_bootstrapdata[] = {
 489     0xA1, 0x81, 0x91, 0x02, 0x12, 0x22, 0x72, 0x62
 490 };
 491
 492 void bcm_init(void)
 493 {
 494     int i;
 495
 496     /* Power up BCM */
 497     GPO32_VAL |= 0x4000;
 498
 499     /* Changed from HZ/2 to speed up this function */
 500     sleep(HZ/8);
 501
 502     /* Bootstrap stage 1 */
 503
 504     STRAP_OPT_A &= ~0xF00;
 505     outl(0x1313, 0x70000040);
 506
 507     /* Interrupt-related code for future use
 508        GPIOC_INT_LEV |= 0x40;
 509        GPIOC_INT_EN |= 0x40;
 510        CPU_HI_INT_EN |= 0x40000;
 511     */
 512
 513     /* Bootstrap stage 2 */
 514
 515     for (i = 0; i < 8; i++) {
 516         BCM_CONTROL = bcm_bootstrapdata[i];
 517     }
 518
 519     for (i = 3; i < 8; i++) {
 520         BCM_ALT_CONTROL = bcm_bootstrapdata[i];
 521     }
 522
 523     while ((BCM_RD_ADDR & 1) == 0 || (BCM_ALT_RD_ADDR & 1) == 0)
 524         yield();
 525
 526     (void)BCM_WR_ADDR;
 527     (void)BCM_ALT_WR_ADDR;
 528
 529     /* Bootstrap stage 3: upload firmware */
 530
 531     while (BCM_ALT_CONTROL & 0x80)
 532         yield();
 533
 534     while (!(BCM_ALT_CONTROL & 0x40))
 535         yield();
 536
 537     /* Upload firmware to BCM SRAM */
 538     bcm_write_addr(BCMA_SRAM_BASE);
 539     lcd_write_data(flash_vmcs_offset, flash_vmcs_length);
 540
 541     bcm_write32(BCMA_COMMAND,  0);
 542     bcm_write32(0x10000C00, 0xC0000000);
 543
 544     while (!(bcm_read32(0x10000C00) & 1))
 545         yield();
 546
 547     bcm_write32(0x10000C00, 0);
 548     bcm_write32(0x10000400, 0xA5A50002);
 549
 550     while (bcm_read32(BCMA_COMMAND) == 0)
 551         yield();
 552
 553     /* sleep(HZ/2) apparently unneeded */
 554 }
 555
 556 void lcd_awake(void)
 557 {
 558     mutex_lock(&lcdstate_lock);
 559     if (!lcd_state.display_on && flash_vmcs_length != 0)
 560     {
 561         /* Ensure BCM has been off for 1/2 s at least */
 562         while (!TIME_AFTER(current_tick, lcd_state.update_timeout))
 563             yield();
 564
 565         bcm_init();
 566
 567         /* Update LCD, but don't use lcd_update().  Instead, wait here
 568            until the command completes so LCD isn't white when the
 569            backlight turns on
 570          */
 571         bcm_write_addr(BCMA_CMDPARAM);
 572         lcd_write_data(&(lcd_framebuffer[0][0]), LCD_WIDTH * LCD_HEIGHT);
 573         bcm_command(BCMCMD_LCD_UPDATE);
 574
 575         lcd_state.state = LCD_INITIAL;
 576         tick_add_task(&lcd_tick);
 577         lcd_state.display_on = true;
 578         /* Note that only the RGB data from lcd_framebuffer has been
 579            displayed.  If YUV data was displayed, it needs to be updated
 580            now.  (eg. see lcd_call_enable_hook())
 581          */
 582     }
 583     mutex_unlock(&lcdstate_lock);
 584 }
 585
 586 void lcd_sleep(void)
 587 {
 588     mutex_lock(&lcdstate_lock);
 589     if (lcd_state.display_on && flash_vmcs_length != 0) {
 590         lcd_state.display_on = false;
 591
 592         /* Wait for BCM to finish work */
 593         while (lcd_state.state != LCD_INITIAL && lcd_state.state != LCD_IDLE)
 594             yield();
 595
 596         tick_remove_task(&lcd_tick);
 597         bcm_powerdown();
 598         bcm_off_wait = current_tick + HZ/2;
 599     }
 600     mutex_unlock(&lcdstate_lock);
 601 }
 602
 603 #ifdef HAVE_LCD_SHUTDOWN
 604 void lcd_shutdown(void)
 605 {
 606     lcd_sleep();
 607 }
 608 #endif /* HAVE_LCD_SHUTDOWN */
 609 #endif /* HAVE_LCD_SLEEP */