rockbox/firmware/lcd.c

/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Copyright (C) 2002 by Alan Korr
 *
 * All files in this archive are subject to the GNU General Public License.
 * See the file COPYING in the source tree root for full license agreement.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ****************************************************************************/

#include "config.h"
#include "lcd.h"

#ifndef SIMULATOR
/*
 * About /CS,DS,SC,SD
 * ------------------
 *
 * LCD on JBP and JBR uses a SPI protocol to receive orders (SDA and SCK lines)
 *
 * - /CS -> Chip Selection line :
 *            0 : LCD chipset is activated.
 * -  DS -> Data Selection line, latched at the rising edge
 *          of the 8th serial clock (*) :
 *            0 : instruction register,
 *            1 : data register; 
 * -  SC -> Serial Clock line (SDA).
 * -  SD -> Serial Data line (SCK), latched at the rising edge
 *          of each serial clock (*).  
 *
 *    _                                                          _
 * /CS \                                                        /
 *      \______________________________________________________/
 *    _____  ____  ____  ____  ____  ____  ____  ____  ____  _____ 
 *  SD     \/ D7 \/ D6 \/ D5 \/ D4 \/ D3 \/ D2 \/ D1 \/ D0 \/
 *    _____/\____/\____/\____/\____/\____/\____/\____/\____/\_____
 *
 *    _____     _     _     _     _     _     _     _     ________ 
 *  SC     \   * \   * \   * \   * \   * \   * \   * \   *
 *          \_/   \_/   \_/   \_/   \_/   \_/   \_/   \_/
 *    _  _________________________________________________________ 
 *  DS \/                                                  
 *    _/\_________________________________________________________
 *
 */

/*
 * The only way to do logical operations in an atomic way
 * on SH1 is using :
 *
 *   or.b/and.b/tst.b/xor.b #imm,@(r0,gbr)
 *
 * but GCC doesn't generate them at all so some assembly
 * codes are needed here.
 *
 * The Global Base Register gbr is expected to be zero
 * and r0 is the address of one register in the on-chip
 * peripheral module.
 *
 */ 

 /*
  * Enter a LCD session :
  *
  * QI(LCDR) &= ~(LCD_CS|LCD_DS|LCD_SD|LCD_SC);
  */
static void lcd_start (void)
{
    asm
        ("and.b\t%0,@(r0,gbr)"
         :
         : /* %0 */ "I"(~(LCD_CS|LCD_DS|LCD_SD|LCD_SC)),
           /* %1 */ "z"(LCDR));
}

 /*
  * Leave a LCD session :
  *
  * QI(LCDR) |= LCD_CS|LCD_RS|LCD_SD|LCD_SC;
  */
static void lcd_stop (void)
{
    asm
        ("or.b\t%0,@(r0,gbr)"
         :
         : /* %0 */ "I"(LCD_CS|LCD_DS|LCD_SD|LCD_SC),
           /* %1 */ "z"(LCDR));
}

static void lcd_byte (int byte,int rs)
 /*
  * char j = 0x80;
  * if (rs)
  *   do
  *     {
  *       QI(LCDR) &= ~(LCD_SC|LCD_SD);
  *       if (j & byte)
  *         QI(LCDR) |= LCD_SD;
  *       QI(LCDR) |= LCD_SC|LCD_DS;
  *     }
  *   while ((unsigned char)j >>= 1);
  * else
  *   do
  *     {
  *       QI(LCDR) &= ~(LCD_SC|LCD_SD|LCD_DS);
  *       if (j & byte)
  *         QI(LCDR) |= LCD_SD;
  *       QI(LCDR) |= LCD_SC;
  *     }
  *   while ((unsigned char)j >>= 1);
  */
{
    if (rs > 0)
        asm
            ("shll8\t%0\n"
             "0:\n\t"
             "and.b\t%2,@(r0,gbr)\n\t"
             "shll\t%0\n\t"  
             "bf\t1f\n\t"
             "or.b\t%3,@(r0,gbr)\n"
             "1:\n\t"
             "or.b\t%4,@(r0,gbr)\n"
             "add\t#-1,%1\n\t"
             "cmp/pl\t%1\n\t"
             "bt\t0b"
             :
             : /* %0 */ "r"(((unsigned)byte)<<16),
             /* %1 */ "r"(8),
             /* %2 */ "I"(~(LCD_SC|LCD_SD)),
             /* %3 */ "I"(LCD_SD),
             /* %4 */ "I"(LCD_SC|LCD_DS),
             /* %5 */ "z"(LCDR));
    else
        asm
            ("shll8\t%0\n"
             "0:\n\t"
             "and.b\t%2,@(r0,gbr)\n\t"
             "shll\t%0\n\t"  
             "bf\t1f\n\t"
             "or.b\t%3,@(r0,gbr)\n"
             "1:\n\t"
             "or.b\t%4,@(r0,gbr)\n"
             "add\t#-1,%1\n\t"
             "cmp/pl\t%1\n\t"
             "bt\t0b"
             :
             : /* %0 */ "r"(((unsigned)byte)<<16),
             /* %1 */ "r"(8),
             /* %2 */ "I"(~(LCD_SC|LCD_DS|LCD_SD)),
             /* %3 */ "I"(LCD_SD),
             /* %4 */ "I"(LCD_SC),
             /* %5 */ "z"(LCDR));
}

void lcd_data (int data)
{
    lcd_byte (data,1);
}

void lcd_instruction (int instruction)
{
    lcd_byte (instruction,0);
}

void lcd_zero (int length)
{
    length *= 8;
    while (--length >= 0)
        lcd_data (0);
}

void lcd_fill (int data,int length)
{
    length *= 8;
    while (--length >= 0)
        lcd_data (data);
}

void lcd_copy (void *data,int count)
{
    while (--count >= 0)
        lcd_data (*((char *)data)++);
}

static void lcd_goto (int x,int y)
{
   lcd_instruction (LCD_CURSOR(x,y));
}

/*** BACKLIGHT ***/

static void lcd_toggle_backlight (void)
{
   PAIOR ^= LCD_BL;
}

static void lcd_turn_on_backlight (void)
{
   PAIOR |= LCD_BL;
}

static void lcd_turn_off_backlight (void)
{
   PAIOR &= ~LCD_BL;
}

/*** ICONS ***/
#endif

#ifdef HAVE_LCD_CHARCELLS
#  ifndef JBP_OLD

static char const lcd_ascii[] =
{
/*****************************************************************************************/
/*         x0   x1   x2   x3   x4   x5   x6   x7   x8   x9   xA   xB   xC   xD   xE   xF */
/*    ************************************************************************************/
/* 0x */ 0x00,0x01,0x02,0x03,0x00,0x00,0x00,0x00,0x04,0x05,0x00,0x00,0x00,0x00,0x00,0x00,
/* 1x */ 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
/* 2x */ 0x20,0x21,0x22,0x23,0x24,0x25,0x26,0x27,0x28,0x29,0x2A,0x2B,0x2C,0x2D,0x2E,0x2F,
/* 3x */ 0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37,0x38,0x39,0x3A,0x3B,0x3C,0x3D,0x3E,0x3F,
/* 4x */ 0x40,0x41,0x42,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4A,0x4B,0x4C,0x4D,0x4E,0x4F,
/* 5x */ 0x50,0x51,0x52,0x53,0x54,0x55,0x56,0x57,0x58,0x59,0x5A,0x5B,0x5C,0x5D,0x5E,0x5F,
/* 6x */ 0x60,0x61,0x62,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6A,0x6B,0x6C,0x6D,0x6E,0x6F,
/* 7x */ 0x70,0x71,0x72,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7A,0x20,0x20,0x20,0x20,0x20,
/* 8x */ 0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,
/* 9x */ 0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,
/* Ax */ 0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,
/* Bx */ 0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,
/* Cx */ 0x41,0x41,0x41,0x41,0x41,0x41,0x20,0x43,0x45,0x45,0x45,0x45,0x49,0x49,0x49,0x49,
/* Dx */ 0x44,0x4E,0x4F,0x4F,0x4F,0x4F,0x4F,0x20,0x20,0x55,0x55,0x55,0x55,0x59,0x20,0x20,
/* Ex */ 0x61,0x61,0x61,0x61,0x61,0x61,0x20,0x63,0x65,0x65,0x65,0x65,0x69,0x69,0x69,0x69,
/* Fx */ 0x64,0x6E,0x6F,0x6F,0x6F,0x6F,0x6F,0x20,0x20,0x75,0x75,0x75,0x75,0x79,0x79,0x79
/******/
  };

#  else

static char const lcd_ascii[] =
  {
/*****************************************************************************************/
/*         x0   x1   x2   x3   x4   x5   x6   x7   x8   x9   xA   xB   xC   xD   xE   xF */
/*    ************************************************************************************/
/* 0x */ 0x00,0x01,0x02,0x03,0x00,0x00,0x00,0x00,0x85,0x89,0x00,0x00,0x00,0x00,0x00,0x00,
/* 1x */ 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
/* 2x */ 0x24,0x25,0x26,0x37,0x06,0x29,0x2A,0x2B,0x2C,0x2D,0x2E,0x2F,0x30,0x31,0x32,0x33,
/* 3x */ 0x34,0x35,0x36,0x37,0x38,0x39,0x3A,0x3B,0x3C,0x3D,0x3E,0x3F,0x40,0x41,0x42,0x43,
/* 4x */ 0x44,0x45,0x46,0x47,0x48,0x49,0x4A,0x4B,0x4C,0x4D,0x4E,0x4F,0x50,0x51,0x52,0x53,
/* 5x */ 0x54,0x55,0x56,0x57,0x58,0x59,0x5A,0x5B,0x5C,0x5D,0x5E,0xA9,0x33,0xCE,0x00,0x15,
/* 6x */ 0x00,0x65,0x66,0x67,0x68,0x69,0x6A,0x6B,0x6C,0x6D,0x6E,0x6F,0x70,0x71,0x72,0x73,
/* 7x */ 0x74,0x75,0x76,0x77,0x78,0x79,0x7A,0x7B,0x7C,0x7D,0x7E,0x24,0x24,0x24,0x24,0x24,
/* 8x */ 0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,
/* 9x */ 0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,
/* Ax */ 0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,
/* Bx */ 0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,
/* Cx */ 0x45,0x45,0x45,0x45,0x45,0x45,0x24,0x47,0x49,0x49,0x49,0x49,0x4D,0x4D,0x4D,0x4D,
/* Dx */ 0x48,0x52,0x53,0x53,0x53,0x53,0x53,0x24,0x24,0x59,0x59,0x59,0x59,0x5D,0x24,0x24,
/* Ex */ 0x65,0x65,0x65,0x65,0x65,0x65,0x24,0x67,0x69,0x69,0x69,0x69,0x6D,0x6D,0x6D,0x6D,
/* Fx */ 0x73,0x72,0x73,0x73,0x73,0x73,0x73,0x24,0x24,0x79,0x79,0x79,0x79,0x7D,0x24,0x7D
/******/
  };

#  endif

void lcd_puts (char const *string)
{
    while (*string)
        lcd_data (LCD_ASCII(*string++));
}

void lcd_putns (char const *string,int n)
{
    while (n--)
        lcd_data (LCD_ASCII(*string++));
}

void lcd_putc (int character)
{
    lcd_data (LCD_ASCII(character));
}

void lcd_pattern (int which,char const *pattern,int count)
{
    lcd_instruction (LCD_PRAM|which);
    lcd_copy ((void *)pattern,count);
}

void lcd_puthex (unsigned int value,int digits)
{
    switch (digits) {
        case 8:
            lcd_puthex (value >> 16,4);
        case 4:
            lcd_puthex (value >> 8,2);
        case 2:
            lcd_puthex (value >> 4,1);
        case 1:
            value &= 15;
            lcd_putc (value+((value < 10) ? '0' : ('A'-10)));
    }
}


/* HAVE_LCD_CHARCELLS */
#elif defined(HAVE_LCD_BITMAP)

/*
 * All bitmaps have this format:
 * Bits within a byte are arranged veritcally, LSB at top.
 * Bytes are stored in column-major format, with byte 0 at top left,
 * byte 1 is 2nd from top, etc.  Bytes following left-most column
 * starts 2nd left column, etc.
 *
 * Note: The HW takes bitmap bytes in row-major order.
 *
 * Memory copy of display bitmap
 */
unsigned char display[DISP_X][DISP_Y/8];

/*
 * ASCII character generation tables
 *
 * This contains only the printable characters (0x20-0x7f).
 * Each element in this table is a character pattern bitmap.
 */
#define	ASCII_MIN			0x20	/* First char in table */
#define	ASCII_MAX			0x7f	/* Last char in table */

extern const unsigned char char_gen_6x8[][5][1];
extern const unsigned char char_gen_8x12[][7][2];
extern const unsigned char char_gen_12x16[][11][2];


/* All zeros and ones bitmaps for area filling */
static const unsigned char zeros[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                                       0x00, 0x00 };
static const unsigned char ones[]  = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
                                       0xff, 0xff };

static int lcd_y;    /* Current pixel row */
static int lcd_x;    /* Current pixel column */
static int lcd_size; /* Current font width */

#ifndef SIMULATOR

/*
 * Initialize LCD
 */
void lcd_init (void)
{
    /* Initialize PB0-3 as output pins */
    PBCR2 &= 0xff00; /* MD = 00 */
    PBIOR |= 0x000f; /* IOR = 1 */

    /* Initialize LCD */
    lcd_write (TRUE, LCD_CNTL_RESET);
    lcd_write (TRUE, LCD_CNTL_POWER);
    lcd_write (TRUE, LCD_CNTL_SEGREMAP);
    lcd_write (TRUE, LCD_CNTL_OUTSCAN);
    lcd_write (TRUE, LCD_CNTL_CONTRAST);
    lcd_write (TRUE, 0x30); /* Contrast parameter */
    lcd_write (TRUE, LCD_CNTL_DISPON);

    lcd_clear_display();
    lcd_update();
}

/*
 * Update the display.
 * This must be called after all other LCD funtions that change the display.
 */
void lcd_update (void)
{
    int x, y;

    /* Copy display bitmap to hardware */
    for (y = 0; y < DISP_Y/8; y++)
    {
        lcd_write (TRUE, LCD_CNTL_PAGE | (y & 0xf));
        lcd_write (TRUE, LCD_CNTL_HIGHCOL);
        lcd_write (TRUE, LCD_CNTL_LOWCOL);

        for (x = 0; x < DISP_X; x++)
            lcd_write (FALSE, display[x][y]);
    }
}

static void lcd_write (bool command, int value)
{
    int bit;

    /* Enable chip select, set DC if data */
    PBDR &= ~(PBDR_LCD_CS1|PBDR_LCD_DC);
    if (!command)
        PBDR |= PBDR_LCD_DC;

    /* Send each bit, starting with MSB */
    for (bit = 0x80; bit > 0; bit >>= 1)
    {
        PBDR &= ~(PBDR_LCD_SDA|PBDR_LCD_SCK);
        if (value & bit)
            PBDR |= PBDR_LCD_SDA;
        PBDR |= PBDR_LCD_SCK;
    }
  
    /* Disable chip select */
    PBDR |= PBDR_LCD_CS1;
}

#endif /* SIMULATOR */

/*
 * Clear the display
 */
void lcd_clear_display (void)
{
    lcd_position (0, 0, 8);
    memset (display, 0, sizeof display);
}

/*
 * Set current x,y position and font size
 */
void lcd_position (int x, int y, int size)
{
    if (x >= 0 && x < DISP_X && y >= 0 && y < DISP_Y)
    {
        lcd_x = x;
        lcd_y = y;
    }

    lcd_size = size;
}

/*
 * Display a string at current position and size
 */
void lcd_string (const char *str)
{
    int x = lcd_x;
    int nx = lcd_size;
    int ny, ch;
    const unsigned char *src;

    if (nx == 12)
        ny = 16;
    else if (nx == 8)
        ny = 12;
    else
    {
        nx = 6;
        ny = 8;
    }

    while ((ch = *str++) != '\0')
    {
        if (ch == '\n' || lcd_x + nx > DISP_X)
        {
            /* Wrap to next line */
            lcd_x = x;
            lcd_y += ny;
        }

        if (lcd_y + ny > DISP_Y)
            return;

        /* Limit to char generation table */
        if (ch >= ASCII_MIN && ch <= ASCII_MAX)
        {
            if (nx == 12)
                src = char_gen_12x16[ch-ASCII_MIN][0];
            else if (nx == 8)
                src = char_gen_8x12[ch-ASCII_MIN][0];
            else
                src = char_gen_6x8[ch-ASCII_MIN][0];

            lcd_bitmap (src, lcd_x, lcd_y, nx-1, ny, TRUE);
            lcd_bitmap (zeros, lcd_x+nx-1, lcd_y, 1, ny, TRUE);

            lcd_x += nx;
        }
    }
}

/*
 * Display a bitmap at (x, y), size (nx, ny)
 * clear is TRUE to clear destination area first
 */
void lcd_bitmap (const unsigned char *src, int x, int y, int nx, int ny,
                 bool clear)
{
    unsigned char *dst;
    unsigned char *dst2 = &display[x][y/8];
    unsigned int data, mask, mask2, mask3, mask4;
    int shift = y & 7;

    ny += shift;

    /* Calculate bit masks */
    mask4 = ~(0xfe << ((ny-1) & 7));
    if (clear)
    {
        mask = ~(0xff << shift);
        mask2 = 0;
        mask3 = ~mask4;
        if (ny <= 8)
            mask3 |= mask;
    }
    else
        mask = mask2 = mask3 = 0xff;

    /* Loop for each column */
    for (x = 0; x < nx; x++)
    {
        dst = dst2;
        dst2 += DISP_Y/8;
        data = 0;
        y = 0;

        if (ny > 8)
        {
            /* First partial row */
            data = *src++ << shift;
            *dst = (*dst & mask) ^ data;
            data >>= 8;
            dst++;

            /* Intermediate rows */
            for (y = 8; y < ny-8; y += 8)
            {
                data |= *src++ << shift;
                *dst = (*dst & mask2) ^ data;
                data >>= 8;
                dst++;
            }
        }

        /* Last partial row */
        if (y + shift < ny)
            data |= *src++ << shift;
        *dst = (*dst & mask3) ^ (data & mask4);
    }
}

/*
 * Clear a rectangular area at (x, y), size (nx, ny)
 */
void lcd_clearrect (int x, int y, int nx, int ny)
{
    int i;
    for (i = 0; i < nx; i++)
        lcd_bitmap (zeros, x+i, y, 1, ny, TRUE);
}

/*
 * Fill a rectangular area at (x, y), size (nx, ny)
 */
void lcd_fillrect (int x, int y, int nx, int ny)
{
    int i;
    for (i = 0; i < nx; i++)
        lcd_bitmap (ones, x+i, y, 1, ny, TRUE);
}

/* Invert a rectangular area at (x, y), size (nx, ny) */
void lcd_invertrect (int x, int y, int nx, int ny)
{
    int i;
    for (i = 0; i < nx; i++)
        lcd_bitmap (ones, x+i, y, 1, ny, FALSE);
}

#define DRAW_PIXEL(x,y) display[x][y/8] |= (1<<(y%8))
#define CLEAR_PIXEL(x,y) display[x][y/8] &= ~(1<<(y%8))

void lcd_drawline( int x1, int y1, int x2, int y2 )
{
    int numpixels;
    int i;
    int deltax, deltay;
    int d, dinc1, dinc2;
    int x, xinc1, xinc2;
    int y, yinc1, yinc2;

    deltax = abs(x2 - x1);
    deltay = abs(y2 - y1);

    if(deltax >= deltay)
    {
        numpixels = deltax;
        d = 2 * deltay - deltax;
        dinc1 = deltay * 2;
        dinc2 = (deltay - deltax) * 2;
        xinc1 = 1;
        xinc2 = 1;
        yinc1 = 0;
        yinc2 = 1;
    }
    else
    {
        numpixels = deltay;
        d = 2 * deltax - deltay;
        dinc1 = deltax * 2;
        dinc2 = (deltax - deltay) * 2;
        xinc1 = 0;
        xinc2 = 1;
        yinc1 = 1;
        yinc2 = 1;
    }
    numpixels++; /* include endpoints */

    if(x1 > x2)
    {
        xinc1 = -xinc1;
        xinc2 = -xinc2;
    }

    if(y1 > y2)
    {
        yinc1 = -yinc1;
        yinc2 = -yinc2;
    }

    x = x1;
    y = y1;

    for(i=0; i<numpixels; i++)
    {
        DRAW_PIXEL(x,y);

        if(d < 0)
        {
            d += dinc1;
            x += xinc1;
            y += yinc1;
        }
        else
        {
            d += dinc2;
            x += xinc2;
            y += yinc2;
        }
    }
}

/*
 * Set a single pixel
 */
void lcd_drawpixel(int x, int y)
{
    DRAW_PIXEL(x,y);
}

/*
 * Clear a single pixel
 */
void lcd_clearpixel(int x, int y)
{
    CLEAR_PIXEL(x,y);
}


#else
/* no LCD defined, no code to use */
#endif

/* -----------------------------------------------------------------
 * local variables:
 * eval: (load-file "rockbox-mode.el")
 * end:
 */