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Diffstat (limited to 'arch/i386/include/asm/i8254.h')
-rw-r--r-- | arch/i386/include/asm/i8254.h | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/arch/i386/include/asm/i8254.h b/arch/i386/include/asm/i8254.h new file mode 100644 index 0000000..aafdfb8 --- /dev/null +++ b/arch/i386/include/asm/i8254.h @@ -0,0 +1,55 @@ +/* + * (C) Copyright 2002 + * Daniel Engström, Omicron Ceti AB, daniel@omicron.se. + * + * 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 + */ + + +/* i8254.h Intel 8254 PIT registers */ + + +#ifndef _ASMI386_I8254_H_ +#define _ASMI386_I8954_H_ 1 + + +#define PIT_T0 0x00 /* PIT channel 0 count/status */ +#define PIT_T1 0x01 /* PIT channel 1 count/status */ +#define PIT_T2 0x02 /* PIT channel 2 count/status */ +#define PIT_COMMAND 0x03 /* PIT mode control, latch and read back */ + +/* PIT Command Register Bit Definitions */ + +#define PIT_CMD_CTR0 0x00 /* Select PIT counter 0 */ +#define PIT_CMD_CTR1 0x40 /* Select PIT counter 1 */ +#define PIT_CMD_CTR2 0x80 /* Select PIT counter 2 */ + +#define PIT_CMD_LATCH 0x00 /* Counter Latch Command */ +#define PIT_CMD_LOW 0x10 /* Access counter bits 7-0 */ +#define PIT_CMD_HIGH 0x20 /* Access counter bits 15-8 */ +#define PIT_CMD_BOTH 0x30 /* Access counter bits 15-0 in two accesses */ + +#define PIT_CMD_MODE0 0x00 /* Select mode 0 */ +#define PIT_CMD_MODE1 0x02 /* Select mode 1 */ +#define PIT_CMD_MODE2 0x04 /* Select mode 2 */ +#define PIT_CMD_MODE3 0x06 /* Select mode 3 */ +#define PIT_CMD_MODE4 0x08 /* Select mode 4 */ +#define PIT_CMD_MODE5 0x0A /* Select mode 5 */ + +#endif |