diff options
Diffstat (limited to 'src/drivers/pc80/pc/i8254.c')
| -rw-r--r-- | src/drivers/pc80/pc/i8254.c | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/src/drivers/pc80/pc/i8254.c b/src/drivers/pc80/pc/i8254.c new file mode 100644 index 0000000000..5851ec08a0 --- /dev/null +++ b/src/drivers/pc80/pc/i8254.c @@ -0,0 +1,51 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2009 coresystems GmbH + * + * 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; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <arch/io.h> +#include <pc80/i8254.h> +#include <console/console.h> + +/* Initialize i8254 timers */ + +void setup_i8254(void) +{ + /* Timer 0 (taken from biosemu) */ + outb(TIMER0_SEL | WORD_ACCESS | MODE3 | BINARY_COUNT, TIMER_MODE_PORT); + outb(0x00, TIMER0_PORT); + outb(0x00, TIMER0_PORT); + + /* Timer 1 */ + outb(TIMER1_SEL | LOBYTE_ACCESS | MODE3 | BINARY_COUNT, + TIMER_MODE_PORT); + outb(0x12, TIMER1_PORT); +} + +#if CONFIG_UDELAY_TIMER2 +static void load_timer2(unsigned int ticks) +{ + /* Set up the timer gate, turn off the speaker */ + outb((inb(PPC_PORTB) & ~PPCB_SPKR) | PPCB_T2GATE, PPC_PORTB); + outb(TIMER2_SEL | WORD_ACCESS | MODE0 | BINARY_COUNT, TIMER_MODE_PORT); + outb(ticks & 0xFF, TIMER2_PORT); + outb(ticks >> 8, TIMER2_PORT); +} + +void udelay(int usecs) +{ + load_timer2((usecs * TICKS_PER_MS) / 1000); + while ((inb(PPC_PORTB) & PPCB_T2OUT) == 0) + ; +} +#endif |