From e000e242a126b517c97f36346aa0634cae000120 Mon Sep 17 00:00:00 2001 From: Jens Arnold Date: Thu, 6 May 2004 06:53:07 +0000 Subject: Faster LCD transfer routines (+35% for the player, +8% for the recorder) git-svn-id: svn://svn.rockbox.org/rockbox/trunk@4577 a1c6a512-1295-4272-9138-f99709370657 --- firmware/drivers/lcd.c | 174 +++++++++++++++++++++++++++---------------------- 1 file changed, 97 insertions(+), 77 deletions(-) (limited to 'firmware/drivers/lcd.c') diff --git a/firmware/drivers/lcd.c b/firmware/drivers/lcd.c index 0df831e259..68627f7c51 100644 --- a/firmware/drivers/lcd.c +++ b/firmware/drivers/lcd.c @@ -8,6 +8,7 @@ * $Id$ * * Copyright (C) 2002 by Alan Korr, speedup by Jörg Hohensohn + * Further speedup and reorganization by Jens Arnold * * 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. @@ -136,7 +137,6 @@ void lcd_write_data(unsigned char* p_bytes, int count) { unsigned int byte; unsigned int sda1; /* precalculated SC=low,SD=1 */ - unsigned int clk0sda0; /* precalculated SC and SD low */ byte = *p_bytes++ << 24; /* fetch to MSB position */ @@ -145,89 +145,108 @@ void lcd_write_data(unsigned char* p_bytes, int count) /* precalculate the values for later bit toggling, init data write */ asm ( - "mov.b @%2,%0 \n" /* sda1 = PBDRL */ - "or %4,%0 \n" /* sda1 |= LCD_DS | LCD_SD DS and SD high, */ - "and %3,%0 \n" /* sda1 &= ~(LCD_CS | LCD_SC) CS and SC low */ - "mov %0,%1 \n" /* sda1 -> clk0sda0 */ - "and %5,%1 \n" /* clk0sda0 &= ~LCD_SD both low */ - "mov.b %1,@%2 \n" /* PBDRL = clk0sda0 */ + "mov.b @%1,r0 \n" /* r0 = PBDRL */ + "or %3,r0 \n" /* r0 |= LCD_DS | LCD_SD DS and SD high */ + "and %2,r0 \n" /* r0 &= ~(LCD_CS | LCD_SC) CS and SC low */ + "mov.b r0,@%1 \n" /* PBDRL = r0 */ + "mov r0,%0 \n" /* sda1 = r0 */ : /* outputs */ - /* %0 */ "=r"(sda1), - /* %1 */ "=r"(clk0sda0) + /* %0 */ "=r"(sda1) : /* inputs */ - /* %2 */ "r"(LCDR), - /* %3 */ "r"(~(LCD_CS | LCD_SC)), - /* %4 */ "r"(LCD_DS | LCD_SD), - /* %5 */ "r"(~LCD_SD) + /* %1 */ "r"(LCDR), + /* %2 */ "I"(~(LCD_CS | LCD_SC)), + /* %3 */ "I"(LCD_DS | LCD_SD) + : /* trashed */ + "r0" ); /* unrolled loop to serialize the byte */ asm ( - "shll %0 \n" /* shift the MSB into carry */ - - "bf 1f \n" - "mov.b %1,@%4 \n" /* if it was a "1": set SD high, SC low still */ - "1: \n" - "or.b %2,@(r0,gbr) \n" /* rise SC (independent of SD level) */ - "shll %0 \n" /* shift for next round, now for longer hold time */ - "mov.b %3,@%4 \n" /* SC and SD low again */ - - "bf 1f \n" - "mov.b %1,@%4 \n" - "1: \n" - "or.b %2,@(r0,gbr) \n" - "shll %0 \n" - "mov.b %3,@%4 \n" - - "bf 1f \n" - "mov.b %1,@%4 \n" - "1: \n" - "or.b %2,@(r0,gbr) \n" - "shll %0 \n" - "mov.b %3,@%4 \n" - - "bf 1f \n" - "mov.b %1,@%4 \n" - "1: \n" - "or.b %2,@(r0,gbr) \n" - "shll %0 \n" - "mov.b %3,@%4 \n" - - "bf 1f \n" - "mov.b %1,@%4 \n" - "1: \n" - "or.b %2,@(r0,gbr) \n" - "shll %0 \n" - "mov.b %3,@%4 \n" - - "bf 1f \n" - "mov.b %1,@%4 \n" - "1: \n" - "or.b %2,@(r0,gbr) \n" - "shll %0 \n" - "mov.b %3,@%4 \n" - - "bf 1f \n" - "mov.b %1,@%4 \n" - "1: \n" - "or.b %2,@(r0,gbr) \n" - "shll %0 \n" - "mov.b %3,@%4 \n" - - "bf 1f \n" - "mov.b %1,@%4 \n" /* set SD high, SC low still */ - "1: \n" - "or.b %2,@(r0,gbr) \n" /* rise SC (independent of SD level) */ - - "or.b %5,@(r0,gbr) \n" /* restore port */ + "shll %0 \n" /* shift the msb into carry */ + ".align 2 \n" + "mov %1,r0 \n" /* copy precalculated port value */ + "bt 1f \n" /* data bit = 1? */ + "and %5,r0 \n" /* no: r0 &= ~LCD_SD */ + "1: \n" + "shll %0 \n" /* next shift here for alignment */ + "mov.b r0,@%3 \n" /* set data to port */ + "or %2,r0 \n" /* rise SC (independent of SD level) */ + "mov.b r0,@%3 \n" /* set to port */ + + "mov %1,r0 \n" + "bt 1f \n" + "and %5,r0 \n" + "1: \n" + "mov.b r0,@%3 \n" + "or %2,r0 \n" + "mov.b r0,@%3 \n" + + "shll %0 \n" + "mov %1,r0 \n" + "bt 1f \n" + "and %5,r0 \n" + "1: \n" + "shll %0 \n" + "mov.b r0,@%3 \n" + "or %2,r0 \n" + "mov.b r0,@%3 \n" + + "mov %1,r0 \n" + "bt 1f \n" + "and %5,r0 \n" + "1: \n" + "mov.b r0,@%3 \n" + "or %2,r0 \n" + "mov.b r0,@%3 \n" + + "shll %0 \n" + "mov %1,r0 \n" + "bt 1f \n" + "and %5,r0 \n" + "1: \n" + "shll %0 \n" + "mov.b r0,@%3 \n" + "or %2,r0 \n" + "mov.b r0,@%3 \n" + + "mov %1,r0 \n" + "bt 1f \n" + "and %5,r0 \n" + "1: \n" + "mov.b r0,@%3 \n" + "or %2,r0 \n" + "mov.b r0,@%3 \n" + + "shll %0 \n" + "mov %1,r0 \n" + "bt 1f \n" + "and %5,r0 \n" + "1: \n" + "shll %0 \n" + "mov.b r0,@%3 \n" + "or %2,r0 \n" + "mov.b r0,@%3 \n" + + "mov %1,r0 \n" + "bt 1f \n" + "and %5,r0 \n" + "1: \n" + "mov.b r0,@%3 \n" + "or %2,r0 \n" + "mov.b r0,@%3 \n" + + "or %4,r0 \n" /* restore port */ + "mov.b r0,@%3 \n" : /* outputs */ : /* inputs */ /* %0 */ "r"(byte), /* %1 */ "r"(sda1), /* %2 */ "I"(LCD_SC), - /* %3 */ "r"(clk0sda0), - /* %4 = r0 */ "z"(LCDR), - /* %5 */ "I"(LCD_CS|LCD_DS|LCD_SD|LCD_SC) + /* %3 */ "r"(LCDR), + /* %4 */ "I"(LCD_CS | LCD_DS | LCD_SD | LCD_SC), + /* %5 */ "I"(~(LCD_SD)) + : /* trashed */ + "r0" ); /* This is the place to reenable the interrupts, if we have disabled @@ -272,12 +291,13 @@ void lcd_write_data(unsigned char* p_bytes, int count) /* unrolled loop to serialize the byte */ asm ( "shll %0 \n" /* shift the MSB into carry */ + ".align 2 \n" "negc %1, r0 \n" /* carry to SD, SC low */ + "shll %0 \n" /* next shift here for alignment */ "mov.b r0,@%3 \n" /* set data to port */ "or %2, r0 \n" /* rise SC (independent of SD level) */ "mov.b r0,@%3 \n" /* set to port */ - "shll %0 \n" "negc %1, r0 \n" "mov.b r0,@%3 \n" "or %2, r0 \n" @@ -285,11 +305,11 @@ void lcd_write_data(unsigned char* p_bytes, int count) "shll %0 \n" "negc %1, r0 \n" + "shll %0 \n" "mov.b r0,@%3 \n" "or %2, r0 \n" "mov.b r0,@%3 \n" - "shll %0 \n" "negc %1, r0 \n" "mov.b r0,@%3 \n" "or %2, r0 \n" @@ -297,11 +317,11 @@ void lcd_write_data(unsigned char* p_bytes, int count) "shll %0 \n" "negc %1, r0 \n" + "shll %0 \n" "mov.b r0,@%3 \n" "or %2, r0 \n" "mov.b r0,@%3 \n" - "shll %0 \n" "negc %1, r0 \n" "mov.b r0,@%3 \n" "or %2, r0 \n" @@ -309,11 +329,11 @@ void lcd_write_data(unsigned char* p_bytes, int count) "shll %0 \n" "negc %1, r0 \n" + "shll %0 \n" "mov.b r0,@%3 \n" "or %2, r0 \n" "mov.b r0,@%3 \n" - "shll %0 \n" "negc %1, r0 \n" "mov.b r0,@%3 \n" "or %2, r0 \n" -- cgit v1.2.3