xref: /netbsd-src/sys/arch/atari/include/dma.h (revision ce0bb6e8d2e560ecacbe865a848624f94498063b)
1 /*	$NetBSD: dma.h,v 1.2 1995/03/26 07:24:35 leo Exp $	*/
2 
3 /*
4  * Copyright (c) 1995 Leo Weppelman.
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  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *      This product includes software developed by Leo Weppelman.
18  * 4. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #ifndef _MACHINE_DMA_H
34 #define _MACHINE_DMA_H
35 
36 /*
37  * Atari TT hardware:
38  * FDC/ACSI DMA circuitry
39  */
40 
41 #define	DMA	((struct dma *)AD_DMA)
42 
43 struct dma {
44 	volatile short	dma_gap[2];	/* reserved			*/
45 	volatile short	dma_data;	/* controller data path		*/
46 	volatile short	dma_mode;	/* mode register		*/
47 	volatile char	dma_addr[6];	/* base address H/M/L		*/
48 	volatile short	dma_drvmode;	/* floppy density settings	*/
49 };
50 
51 #define	dma_nsec      dma_data		/* sector count			*/
52 #define	dma_stat      dma_mode		/* status register		*/
53 
54 /*
55  * Mode register bits
56  */
57 /*		0x0001		*//* not used				*/
58 #define	A0	0x0002		/* signal A0 to fdc/hdc			*/
59 #define	A1	0x0004		/* signal A1 to fdc/hdc			*/
60 #define	HDC	0x0008		/* must be on if accessing hdc		*/
61 #define	SCREG	0x0010		/* access sector count register		*/
62 /*		0x0020		*//* reserved				*/
63 #define	NODMA	0x0040		/* no DMA (yet)				*/
64 #define	FDC	0x0080		/* must be on if accessing fdc		*/
65 #define	WRBIT	0x0100		/* write to fdc/hdc via dma_data	*/
66 
67 /*
68  * Status register bits
69  */
70 #define	DMAOK	0x0001		/* something wrong			*/
71 #define	SCNOT0	0x0002		/* sector count not 0			*/
72 #define	DATREQ	0x0004		/* FDC data request signal		*/
73 
74 /*
75  * Indices into dma_addr.
76  * Access low byte of 16 bits.
77  * Fill low/mid/high in this order.
78  */
79 #define	AD_HIGH	1
80 #define	AD_MID	3
81 #define	AD_LOW	5
82 
83 /*
84  * Defines for 'dmadrv_mode'.
85  */
86 #define	FDC_HDSET	1	/* Set FDC for High density		*/
87 #define	FDC_HDSIG	2	/* Signal HD present to drive		*/
88 #endif /* _MACHINE_DMA_H */
89