X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=arch%2Fx86%2Flib%2Fpcat_timer.c;h=3545a5048e0c9f883263eed8a6a20bf1d9fc1b9a;hb=4b19b7448e63bab8af17abbb30acff00d8f0dc99;hp=1911c6c19d24365393420b271d3a51e0b71adef3;hpb=909e9bf3ae6195ac6d52f9e453fba2be8e7e947f;p=u-boot diff --git a/arch/x86/lib/pcat_timer.c b/arch/x86/lib/pcat_timer.c index 1911c6c19d..3545a5048e 100644 --- a/arch/x86/lib/pcat_timer.c +++ b/arch/x86/lib/pcat_timer.c @@ -1,107 +1,27 @@ /* * (C) Copyright 2002 - * Daniel Engström, Omicron Ceti AB, + * Daniel Engström, Omicron Ceti AB, * - * See file CREDITS for list of people who contributed to this - * project. - * - * 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 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. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, - * MA 02111-1307 USA + * SPDX-License-Identifier: GPL-2.0+ */ #include #include #include -#include -#include -#define TIMER0_VALUE 0x04aa /* 1kHz 1.9318MHz / 1000 */ #define TIMER2_VALUE 0x0a8e /* 440Hz */ -static int timer_init_done = 0; - -int timer_init(void) +int pcat_timer_init(void) { - /* initialize timer 0 and 2 - * - * Timer 0 is used to increment system_tick 1000 times/sec - * Timer 1 was used for DRAM refresh in early PC's - * Timer 2 is used to drive the speaker - * (to stasrt a beep: write 3 to port 0x61, + /* + * initialize 2, used to drive the speaker + * (to start a beep: write 3 to port 0x61, * to stop it again: write 0) */ - outb (PIT_CMD_CTR0 | PIT_CMD_BOTH | PIT_CMD_MODE2, - PIT_BASE + PIT_COMMAND); - outb (TIMER0_VALUE & 0xff, PIT_BASE + PIT_T0); - outb (TIMER0_VALUE >> 8, PIT_BASE + PIT_T0); - - outb (PIT_CMD_CTR2 | PIT_CMD_BOTH | PIT_CMD_MODE3, - PIT_BASE + PIT_COMMAND); - outb (TIMER2_VALUE & 0xff, PIT_BASE + PIT_T2); - outb (TIMER2_VALUE >> 8, PIT_BASE + PIT_T2); - - irq_install_handler (0, timer_isr, NULL); - unmask_irq (0); - - timer_init_done = 1; + outb(PIT_CMD_CTR2 | PIT_CMD_BOTH | PIT_CMD_MODE3, + PIT_BASE + PIT_COMMAND); + outb(TIMER2_VALUE & 0xff, PIT_BASE + PIT_T2); + outb(TIMER2_VALUE >> 8, PIT_BASE + PIT_T2); return 0; } - -static u16 read_pit(void) -{ - u8 low; - - outb (PIT_CMD_LATCH, PIT_BASE + PIT_COMMAND); - low = inb (PIT_BASE + PIT_T0); - - return ((inb (PIT_BASE + PIT_T0) << 8) | low); -} - -/* this is not very exact */ -void __udelay (unsigned long usec) -{ - int counter; - int wraps; - - if (timer_init_done) - { - counter = read_pit (); - wraps = usec / 1000; - usec = usec % 1000; - - usec *= 1194; - usec /= 1000; - usec += counter; - - while (usec > 1194) { - usec -= 1194; - wraps++; - } - - while (1) { - int new_count = read_pit (); - - if (((new_count < usec) && !wraps) || wraps < 0) - break; - - if (new_count > counter) - wraps--; - - counter = new_count; - } - } - -}