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i8259.h (3581B) - Raw


      1 /*-
      2  * SPDX-License-Identifier: BSD-2-Clause
      3  *
      4  * Copyright (c) 2003 Peter Wemm
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
     17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     26  * SUCH DAMAGE.
     27  */
     28 
     29 /*
     30  * Register defintions for the i8259A programmable interrupt controller.
     31  */
     32 
     33 #ifndef _DEV_IC_I8259_H_
     34 #define	_DEV_IC_I8259_H_
     35 
     36 /* Initialization control word 1. Written to even address. */
     37 #define	ICW1_IC4	0x01		/* ICW4 present */
     38 #define	ICW1_SNGL	0x02		/* 1 = single, 0 = cascaded */
     39 #define	ICW1_ADI	0x04		/* 1 = 4, 0 = 8 byte vectors */
     40 #define	ICW1_LTIM	0x08		/* 1 = level trigger, 0 = edge */
     41 #define	ICW1_RESET	0x10		/* must be 1 */
     42 /* 0x20 - 0x80 - in 8080/8085 mode only */
     43 
     44 /* Initialization control word 2. Written to the odd address. */
     45 /* No definitions, it is the base vector of the IDT for 8086 mode */
     46 
     47 /* Initialization control word 3. Written to the odd address. */
     48 /* For a master PIC, bitfield indicating a slave 8259 on given input */
     49 /* For slave, lower 3 bits are the slave's ID binary id on master */
     50 
     51 /* Initialization control word 4. Written to the odd address. */
     52 #define	ICW4_8086	0x01		/* 1 = 8086, 0 = 8080 */
     53 #define	ICW4_AEOI	0x02		/* 1 = Auto EOI */
     54 #define	ICW4_MS		0x04		/* 1 = buffered master, 0 = slave */
     55 #define	ICW4_BUF	0x08		/* 1 = enable buffer mode */
     56 #define	ICW4_SFNM	0x10		/* 1 = special fully nested mode */
     57 
     58 /* Operation control words.  Written after initialization. */
     59 
     60 /* Operation control word type 1 */
     61 /*
     62  * No definitions.  Written to the odd address.  Bitmask for interrupts.
     63  * 1 = disabled.
     64  */
     65 
     66 /* Operation control word type 2.  Bit 3 (0x08) must be zero. Even address. */
     67 #define	OCW2_L0		0x01		/* Level */
     68 #define	OCW2_L1		0x02
     69 #define	OCW2_L2		0x04
     70 /* 0x08 must be 0 to select OCW2 vs OCW3 */
     71 /* 0x10 must be 0 to select OCW2 vs ICW1 */
     72 #define	OCW2_EOI	0x20		/* 1 = EOI */
     73 #define	OCW2_SL		0x40		/* EOI mode */
     74 #define	OCW2_R		0x80		/* EOI mode */
     75 
     76 /* Operation control word type 3.  Bit 3 (0x08) must be set. Even address. */
     77 #define	OCW3_RIS	0x01		/* 1 = read IS, 0 = read IR */
     78 #define	OCW3_RR		0x02		/* register read */
     79 #define	OCW3_P		0x04		/* poll mode command */
     80 /* 0x08 must be 1 to select OCW3 vs OCW2 */
     81 #define	OCW3_SEL	0x08		/* must be 1 */
     82 /* 0x10 must be 0 to select OCW3 vs ICW1 */
     83 #define	OCW3_SMM	0x20		/* special mode mask */
     84 #define	OCW3_ESMM	0x40		/* enable SMM */
     85 
     86 #endif /* !_DEV_IC_I8259_H_ */