text: /***************************************************************************
   *             __________               __   ___.
   *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   *                     \/            \/     \/    \/            \/
   * $Id$
   *
   * Copyright (C) 2009 by Mark Arigo
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License
   * as published by the Free Software Foundation; either version 2
   * of the License, or (at your option) any later version.
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
   * KIND, either express or implied.
   *
   ****************************************************************************/
  #include "config.h"
  #include "cpu.h"
  #include "lcd.h"
  #include "kernel.h"
  #include "system.h"
  
  /* register defines for Philips LCD 220x176x16 - model: LPH9165-2 */
  #define LCD_REG_UNKNOWN_00        0x00
  #define LCD_REG_UNKNOWN_01        0x01
  #define LCD_REG_UNKNOWN_05        0x05
  #define LCD_REG_WRITE_DATA_2_GRAM 0x06
  #define LCD_REG_HORIZ_ADDR_START  0x08
  #define LCD_REG_HORIZ_ADDR_END    0x09
  #define LCD_REG_VERT_ADDR_START   0x0a
  #define LCD_REG_VERT_ADDR_END     0x0b
  
  /* whether the lcd is currently enabled or not */
  static bool lcd_enabled;
  
  /* Display status */
  static unsigned lcd_yuv_options SHAREDBSS_ATTR = 0;
  
  /* Value used for flipping. Must be remembered when display is turned off. */
  static unsigned short flip;
  
  /* Used for flip offset correction */
  static int x_offset;
  
  /* Inverse value. Must be remembered when display is turned off. */
  static unsigned short invert;
  
  /* wait for LCD */
  static inline void lcd_wait_write(void)
  {
      while (LCD2_PORT & LCD2_BUSY_MASK);
  }
  
  /* send LCD data */
  static void lcd_send_data(unsigned data)
  {
      lcd_wait_write();
      LCD2_PORT = LCD2_DATA_MASK | (data & 0xff);
  }
  
  /* send LCD command */
  static void lcd_send_reg(unsigned reg)
  {
      lcd_wait_write();
      LCD2_PORT = LCD2_CMD_MASK | (reg & 0xff);
      lcd_wait_write();
  }
  
  void lcd_init_device(void)
  {
      x_offset = 16;
      invert = 0x00;
      flip   = 0x40;
  
      lcd_enabled = true;
  }
  
  #ifdef HAVE_LCD_ENABLE
  /* enable / disable lcd */
  void lcd_enable(bool on)
  {
      if (on == lcd_enabled)
          return;
  
      if (on) /* lcd_display_on() */
      {
          lcd_send_reg(LCD_REG_UNKNOWN_00);
          lcd_send_data(0x00 | invert);
          lcd_send_reg(LCD_REG_UNKNOWN_01);
          lcd_send_data(0x08 | flip);
          lcd_send_reg(LCD_REG_UNKNOWN_05);
          lcd_send_data(0x0f);
          sleep(HZ/10); /* 100ms */
  
          /* Probably out of sync and we don't wanna pepper the code with
             lcd_update() calls for this. */
          lcd_update();
          send_event(LCD_EVENT_ACTIVATION, NULL);
  
          lcd_enabled = true;
      }
      else /* lcd_display_off() */
      {
          lcd_send_reg(LCD_REG_UNKNOWN_00);
          lcd_send_data(0x08);
  
          lcd_enabled = false;
      }
  }
  
  
  bool lcd_active(void)
  {
      return lcd_enabled;
  }
  #endif /* HAVE_LCD_ENABLE */
  
  
  /*** hardware configuration ***/
  int lcd_default_contrast(void)
  {
      return DEFAULT_CONTRAST_SETTING;
  }
  
  void lcd_set_contrast(int val)
  {
      (void)val;
  }
  
  void lcd_set_invert_display(bool yesno)
  {
      invert = (yesno) ? 0x40 : 0x00;
      lcd_send_reg(LCD_REG_UNKNOWN_00);
      lcd_send_data(invert);
  }
  
  /* turn the display upside down (call lcd_update() afterwards) */
  void lcd_set_flip(bool yesno)
  {
      flip = (yesno) ? 0x80 : 0x40;
      x_offset = (yesno) ? 4 : 16;
      lcd_send_reg(LCD_REG_UNKNOWN_01);
      lcd_send_data(0x08 | flip);
  }
  
  void lcd_yuv_set_options(unsigned options)
  {
      lcd_yuv_options = options;
  }
  
  #define CSUB_X 2
  #define CSUB_Y 2
  
  /*   YUV- > RGB565 conversion
   *   |R|   |1.000000 -0.000001  1.402000| |Y'|
   *   |G| = |1.000000 -0.334136 -0.714136| |Pb|
   *   |B|   |1.000000  1.772000  0.000000| |Pr|
   *   Scaled, normalized, rounded and tweaked to yield RGB 565:
   *   |R|   |74   0 101| |Y' -  16| >> 9
   *   |G| = |74 -24 -51| |Cb - 128| >> 8
   *   |B|   |74 128   0| |Cr - 128| >> 9
  */
  
  extern void lcd_yuv_write_inner_loop(unsigned char const * const ysrc,
                                       unsigned char const * const usrc,
                                       unsigned char const * const vsrc,
                                       int width);
  
  /* Performance function to blit a YUV bitmap directly to the LCD */
  void lcd_blit_yuv(unsigned char * const src[3],
                    int src_x, int src_y, int stride,
                    int x, int y, int width, int height)
  {
      int h;
  
      width = (width + 1) & ~1;
  
      lcd_send_reg(LCD_REG_HORIZ_ADDR_START);
      lcd_send_data(y);
  
      lcd_send_reg(LCD_REG_HORIZ_ADDR_END);
      lcd_send_data(y + height - 1);
  
      lcd_send_reg(LCD_REG_VERT_ADDR_START);
      lcd_send_data(x + x_offset);
  
      lcd_send_reg(LCD_REG_VERT_ADDR_END);
      lcd_send_data(x + width - 1 + x_offset);
  
      lcd_send_reg(LCD_REG_WRITE_DATA_2_GRAM);
  
      const int stride_div_csub_x = stride/CSUB_X;
  
      h=0;
      while (1)
      {
          /* upsampling, YUV->RGB conversion and reduction to RGB565 in one go */
          const unsigned char *ysrc = src[0] + stride * src_y + src_x;
  
          const int uvoffset = stride_div_csub_x * (src_y/CSUB_Y) +
                               (src_x/CSUB_X);
  
          const unsigned char *usrc = src[1] + uvoffset;
          const unsigned char *vsrc = src[2] + uvoffset;
  
          int pixels_to_write;
  
          if (h==0)
          {
              while (!(LCD2_BLOCK_CTRL & LCD2_BLOCK_READY));
              LCD2_BLOCK_CONFIG = 0;
  
              if (height == 0) break;
  
              pixels_to_write = (width * height) * 2;
              h = height;
  
              /* calculate how much we can do in one go */
              if (pixels_to_write > 0x10000)
              {
                  h = (0x10000/2) / width;
                  pixels_to_write = (width * h) * 2;
              }
  
              height -= h;
              LCD2_BLOCK_CTRL = 0x10000080;
              LCD2_BLOCK_CONFIG = 0xc0010000 | (pixels_to_write - 1);
              LCD2_BLOCK_CTRL = 0x34000000;
          }
  
          lcd_yuv_write_inner_loop(ysrc,usrc,vsrc,width);
  
          src_y++;
          h--;
      }
  
      while (!(LCD2_BLOCK_CTRL & LCD2_BLOCK_READY));
      LCD2_BLOCK_CONFIG = 0;
  }
  
  /* Update the display.
     This must be called after all other LCD functions that change the display. */
  void lcd_update(void)
  {
      lcd_update_rect(0, 0, LCD_WIDTH, LCD_HEIGHT);
  }
  
  /* Update a fraction of the display. */
  void lcd_update_rect(int x, int y, int width, int height)
  {
      unsigned long *addr;
      int new_x, new_width;
  
      /* Ensure x and width are both even - so we can read 32-bit aligned
         data from lcd_framebuffer */
      new_x = x&~1;
      new_width = width&~1;
      if (new_x+new_width < x+width) new_width += 2;
      x = new_x;
      width = new_width;
  
      if (x + width >= LCD_WIDTH)
          width = LCD_WIDTH - x;
      if (y + height >= LCD_HEIGHT)
          height = LCD_HEIGHT - y;
  
      if ((width <= 0) || (height <= 0))
          return; /* Nothing left to do. */
  
      lcd_send_reg(LCD_REG_HORIZ_ADDR_START);
      lcd_send_data(y);
  
      lcd_send_reg(LCD_REG_HORIZ_ADDR_END);
      lcd_send_data(y + height - 1);
  
      lcd_send_reg(LCD_REG_VERT_ADDR_START);
      lcd_send_data(x + x_offset);
  
      lcd_send_reg(LCD_REG_VERT_ADDR_END);
      lcd_send_data(x + width - 1 + x_offset);
  
      lcd_send_reg(LCD_REG_WRITE_DATA_2_GRAM);
  
      addr = (unsigned long*)FBADDR(x,y);
  
      while (height > 0)
      {
          int c, r;
          int h, pixels_to_write;
  
          pixels_to_write = (width * height) * 2;
          h = height;
  
          /* calculate how much we can do in one go */
          if (pixels_to_write > 0x10000)
          {
              h = (0x10000/2) / width;
              pixels_to_write = (width * h) * 2;
          }
  
          LCD2_BLOCK_CTRL = 0x10000080;
          LCD2_BLOCK_CONFIG = 0xc0010000 | (pixels_to_write - 1);
          LCD2_BLOCK_CTRL = 0x34000000;
  
          /* for each row */
          for (r = 0; r < h; r++)
          {
              /* for each column */
              for (c = 0; c < width; c += 2)
              {
                  while (!(LCD2_BLOCK_CTRL & LCD2_BLOCK_TXOK));
  
                  /* output 2 pixels */
                  LCD2_BLOCK_DATA = *addr++;
              }
              addr += (LCD_WIDTH - width)/2;
          }
  
          while (!(LCD2_BLOCK_CTRL & LCD2_BLOCK_READY));
          LCD2_BLOCK_CONFIG = 0;
  
          height -= h;
      }
  }
  