rockbox/firmware/target/arm/as3525/sansa-clipv2/lcd-clipv2.c
William Wilgus dcd71e66bd Optimize lcd-ssd1303 driver (clip series)
Saves 100+ bytes (50 of it in iram), saves a bit of power

Internal LCD clock decreased but with added efficiency of drawing routines
loses only around 2 Hz on the scanrate (~75Hz) while fps is slightly increased

Column offsets are now calculated outside the loops saving a few instructions

Passing a LCD_NOP command after lcd_update turns off Data/Cmd# gpio
saving a bit more power

Added a function lcd_write_cmd_triple() that allows 3 commands to be sent at once
when enabled with LCD_USE_FIFO_FOR_COMMANDS it sends them back to back without
checking FIFO status in between or sending to thhe D/C# Gpio.
Makes an assumption about the FIFO being large enough to
accept 3 commands after being emptied which should be the case on the
clipv1, clipv2, clipplus. I have only enabled it for the clip plus
as thats the only device I have to test it on.

On clip+ the SSP clock is now turned off when screen is off

Change-Id: Ib5fd24697bfe4ac8b8ee017361e789e4a7910d21
2018-07-26 04:23:28 +02:00

121 lines
3 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2008 François Dinel
* Copyright (C) 2008-2009 Rafaël Carré
*
* 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 "lcd.h"
#include "lcd-clip.h"
#include "system.h"
#include "cpu.h"
#define LCD_DELAY 10
int lcd_hw_init(void)
{
/* DBOP initialisation, do what OF does */
bitset32(&CCU_IO, 1<<12); /* ?? */
CGU_DBOP |= /*(1<<3)*/ 0x18 | AS3525_DBOP_DIV;
DBOP_CTRL = 0x51004;
DBOP_TIMPOL_01 = 0x36A12F;
DBOP_TIMPOL_23 = 0xE037E037;
GPIOB_DIR |= (1<<2)|(1<<5);
GPIOB_PIN(5) = (1<<5);
return 0;
}
void lcd_write_command(int byte)
{
volatile int i = 0;
while(i<LCD_DELAY) i++;
/* unset D/C# (data or command) */
GPIOB_PIN(2) = 0;
DBOP_TIMPOL_23 = 0xE0370036;
/* Write command */
DBOP_DOUT8 = byte;
/* While push fifo is not empty */
while ((DBOP_STAT & (1<<10)) == 0)
;
DBOP_TIMPOL_23 = 0xE037E037;
}
void lcd_write_cmd_triplet(int cmd1, int cmd2, int cmd3)
{
#ifndef LCD_USE_FIFO_FOR_COMMANDS
lcd_write_command(cmd1);
lcd_write_command(cmd2);
lcd_write_command(cmd3);
#else
/* combine writes to data register */
while ((DBOP_STAT & (1<<10)) == 0) /* While push fifo is not empty */
;
/* FIFO is empty at this point */
/* unset D/C# (data or command) */
GPIOB_PIN(2) = 0;
DBOP_TIMPOL_23 = 0xE0370036;
/* Write command */
/* !!makes assumption FIFO is at least (3) levels deep! */
DBOP_DOUT8 = cmd1;
DBOP_DOUT8 = cmd2;
DBOP_DOUT8 = cmd3;
/* While push fifo is not empty */
while ((DBOP_STAT & (1<<10)) == 0)
;
DBOP_TIMPOL_23 = 0xE037E037;
#endif
}
void lcd_write_data(const fb_data* p_bytes, int count)
{
volatile int i = 0;
while(i<LCD_DELAY) i++;
/* set D/C# (data or command) */
GPIOB_PIN(2) = (1<<2);
while (count--)
{
/* Write pixels */
DBOP_DOUT8 = *p_bytes;
p_bytes++; /* next packed pixels */
/* Wait if push fifo is full */
while ((DBOP_STAT & (1<<6)) != 0);
}
/* While push fifo is not empty */
while ((DBOP_STAT & (1<<10)) == 0);
}
void lcd_enable_power(bool onoff)
{
(void) onoff;
}