1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * mesh.h: definitions for the driver for the MESH SCSI bus adaptor
4 * (Macintosh Enhanced SCSI Hardware) found on Power Macintosh computers.
5 *
6 * Copyright (C) 1996 Paul Mackerras.
7 */
8#ifndef _MESH_H
9#define _MESH_H
10
11struct mesh_cmd_priv {
12	int this_residual;
13	int message;
14	int status;
15};
16
17static inline struct mesh_cmd_priv *mesh_priv(struct scsi_cmnd *cmd)
18{
19	return scsi_cmd_priv(cmd);
20}
21
22/*
23 * Registers in the MESH controller.
24 */
25
26struct mesh_regs {
27	unsigned char	count_lo;
28	char pad0[15];
29	unsigned char	count_hi;
30	char pad1[15];
31	unsigned char	fifo;
32	char pad2[15];
33	unsigned char	sequence;
34	char pad3[15];
35	unsigned char	bus_status0;
36	char pad4[15];
37	unsigned char	bus_status1;
38	char pad5[15];
39	unsigned char	fifo_count;
40	char pad6[15];
41	unsigned char	exception;
42	char pad7[15];
43	unsigned char	error;
44	char pad8[15];
45	unsigned char	intr_mask;
46	char pad9[15];
47	unsigned char	interrupt;
48	char pad10[15];
49	unsigned char	source_id;
50	char pad11[15];
51	unsigned char	dest_id;
52	char pad12[15];
53	unsigned char	sync_params;
54	char pad13[15];
55	unsigned char	mesh_id;
56	char pad14[15];
57	unsigned char	sel_timeout;
58	char pad15[15];
59};
60
61/* Bits in the sequence register. */
62#define SEQ_DMA_MODE	0x80	/* use DMA for data transfer */
63#define SEQ_TARGET	0x40	/* put the controller into target mode */
64#define SEQ_ATN		0x20	/* assert ATN signal */
65#define SEQ_ACTIVE_NEG	0x10	/* use active negation on REQ/ACK */
66#define SEQ_CMD		0x0f	/* command bits: */
67#define SEQ_ARBITRATE	1	/*  get the bus */
68#define SEQ_SELECT	2	/*  select a target */
69#define SEQ_COMMAND	3	/*  send a command */
70#define SEQ_STATUS	4	/*  receive status */
71#define SEQ_DATAOUT	5	/*  send data */
72#define SEQ_DATAIN	6	/*  receive data */
73#define SEQ_MSGOUT	7	/*  send a message */
74#define SEQ_MSGIN	8	/*  receive a message */
75#define SEQ_BUSFREE	9	/*  look for bus free */
76#define SEQ_ENBPARITY	0x0a	/*  enable parity checking */
77#define SEQ_DISPARITY	0x0b	/*  disable parity checking */
78#define SEQ_ENBRESEL	0x0c	/*  enable reselection */
79#define SEQ_DISRESEL	0x0d	/*  disable reselection */
80#define SEQ_RESETMESH	0x0e	/*  reset the controller */
81#define SEQ_FLUSHFIFO	0x0f	/*  clear out the FIFO */
82
83/* Bits in the bus_status0 and bus_status1 registers:
84   these correspond directly to the SCSI bus control signals. */
85#define BS0_REQ		0x20
86#define BS0_ACK		0x10
87#define BS0_ATN		0x08
88#define BS0_MSG		0x04
89#define BS0_CD		0x02
90#define BS0_IO		0x01
91#define BS1_RST		0x80
92#define BS1_BSY		0x40
93#define BS1_SEL		0x20
94
95/* Bus phases defined by the bits in bus_status0 */
96#define BS0_PHASE	(BS0_MSG+BS0_CD+BS0_IO)
97#define BP_DATAOUT	0
98#define BP_DATAIN	BS0_IO
99#define BP_COMMAND	BS0_CD
100#define BP_STATUS	(BS0_CD+BS0_IO)
101#define BP_MSGOUT	(BS0_MSG+BS0_CD)
102#define BP_MSGIN	(BS0_MSG+BS0_CD+BS0_IO)
103
104/* Bits in the exception register. */
105#define EXC_SELWATN	0x20	/* (as target) we were selected with ATN */
106#define EXC_SELECTED	0x10	/* (as target) we were selected w/o ATN */
107#define EXC_RESELECTED	0x08	/* (as initiator) we were reselected */
108#define EXC_ARBLOST	0x04	/* we lost arbitration */
109#define EXC_PHASEMM	0x02	/* SCSI phase mismatch */
110#define EXC_SELTO	0x01	/* selection timeout */
111
112/* Bits in the error register */
113#define ERR_UNEXPDISC	0x40	/* target unexpectedly disconnected */
114#define ERR_SCSIRESET	0x20	/* SCSI bus got reset on us */
115#define ERR_SEQERR	0x10	/* we did something the chip didn't like */
116#define ERR_PARITY	0x01	/* parity error was detected */
117
118/* Bits in the interrupt and intr_mask registers */
119#define INT_ERROR	0x04	/* error interrupt */
120#define INT_EXCEPTION	0x02	/* exception interrupt */
121#define INT_CMDDONE	0x01	/* command done interrupt */
122
123/* Fields in the sync_params register */
124#define SYNC_OFF(x)	((x) >> 4)	/* offset field */
125#define SYNC_PER(x)	((x) & 0xf)	/* period field */
126#define SYNC_PARAMS(o, p)	(((o) << 4) | (p))
127#define ASYNC_PARAMS	2	/* sync_params value for async xfers */
128
129/*
130 * Assuming a clock frequency of 50MHz:
131 *
132 * The transfer period with SYNC_PER(sync_params) == x
133 * is (x + 2) * 40ns, except that x == 0 gives 100ns.
134 *
135 * The units of the sel_timeout register are 10ms.
136 */
137
138
139#endif /* _MESH_H */
140