diff options
Diffstat (limited to 'drivers/scsi/mesh.h')
| -rw-r--r-- | drivers/scsi/mesh.h | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/drivers/scsi/mesh.h b/drivers/scsi/mesh.h new file mode 100644 index 000000000..4fdb81fa5 --- /dev/null +++ b/drivers/scsi/mesh.h @@ -0,0 +1,127 @@ +/* + * mesh.h: definitions for the driver for the MESH SCSI bus adaptor + * (Macintosh Enhanced SCSI Hardware) found on Power Macintosh computers. + * + * Copyright (C) 1996 Paul Mackerras. + */ +#ifndef _MESH_H +#define _MESH_H + +/* + * Registers in the MESH controller. + */ + +struct mesh_regs { + unsigned char count_lo; + char pad0[15]; + unsigned char count_hi; + char pad1[15]; + unsigned char fifo; + char pad2[15]; + unsigned char sequence; + char pad3[15]; + unsigned char bus_status0; + char pad4[15]; + unsigned char bus_status1; + char pad5[15]; + unsigned char fifo_count; + char pad6[15]; + unsigned char exception; + char pad7[15]; + unsigned char error; + char pad8[15]; + unsigned char intr_mask; + char pad9[15]; + unsigned char interrupt; + char pad10[15]; + unsigned char source_id; + char pad11[15]; + unsigned char dest_id; + char pad12[15]; + unsigned char sync_params; + char pad13[15]; + unsigned char mesh_id; + char pad14[15]; + unsigned char sel_timeout; + char pad15[15]; +}; + +/* Bits in the sequence register. */ +#define SEQ_DMA_MODE 0x80 /* use DMA for data transfer */ +#define SEQ_TARGET 0x40 /* put the controller into target mode */ +#define SEQ_ATN 0x20 /* assert ATN signal */ +#define SEQ_ACTIVE_NEG 0x10 /* use active negation on REQ/ACK */ +#define SEQ_CMD 0x0f /* command bits: */ +#define SEQ_ARBITRATE 1 /* get the bus */ +#define SEQ_SELECT 2 /* select a target */ +#define SEQ_COMMAND 3 /* send a command */ +#define SEQ_STATUS 4 /* receive status */ +#define SEQ_DATAOUT 5 /* send data */ +#define SEQ_DATAIN 6 /* receive data */ +#define SEQ_MSGOUT 7 /* send a message */ +#define SEQ_MSGIN 8 /* receive a message */ +#define SEQ_BUSFREE 9 /* look for bus free */ +#define SEQ_ENBPARITY 0x0a /* enable parity checking */ +#define SEQ_DISPARITY 0x0b /* disable parity checking */ +#define SEQ_ENBRESEL 0x0c /* enable reselection */ +#define SEQ_DISRESEL 0x0d /* disable reselection */ +#define SEQ_RESETMESH 0x0e /* reset the controller */ +#define SEQ_FLUSHFIFO 0x0f /* clear out the FIFO */ + +/* Bits in the bus_status0 and bus_status1 registers: + these correspond directly to the SCSI bus control signals. */ +#define BS0_REQ 0x20 +#define BS0_ACK 0x10 +#define BS0_ATN 0x08 +#define BS0_MSG 0x04 +#define BS0_CD 0x02 +#define BS0_IO 0x01 +#define BS1_RST 0x80 +#define BS1_BSY 0x40 +#define BS1_SEL 0x20 + +/* Bus phases defined by the bits in bus_status0 */ +#define BS0_PHASE (BS0_MSG+BS0_CD+BS0_IO) +#define BP_DATAOUT 0 +#define BP_DATAIN BS0_IO +#define BP_COMMAND BS0_CD +#define BP_STATUS (BS0_CD+BS0_IO) +#define BP_MSGOUT (BS0_MSG+BS0_CD) +#define BP_MSGIN (BS0_MSG+BS0_CD+BS0_IO) + +/* Bits in the exception register. */ +#define EXC_SELWATN 0x20 /* (as target) we were selected with ATN */ +#define EXC_SELECTED 0x10 /* (as target) we were selected w/o ATN */ +#define EXC_RESELECTED 0x08 /* (as initiator) we were reselected */ +#define EXC_ARBLOST 0x04 /* we lost arbitration */ +#define EXC_PHASEMM 0x02 /* SCSI phase mismatch */ +#define EXC_SELTO 0x01 /* selection timeout */ + +/* Bits in the error register */ +#define ERR_UNEXPDISC 0x40 /* target unexpectedly disconnected */ +#define ERR_SCSIRESET 0x20 /* SCSI bus got reset on us */ +#define ERR_SEQERR 0x10 /* we did something the chip didn't like */ +#define ERR_PARITY 0x01 /* parity error was detected */ + +/* Bits in the interrupt and intr_mask registers */ +#define INT_ERROR 0x04 /* error interrupt */ +#define INT_EXCEPTION 0x02 /* exception interrupt */ +#define INT_CMDDONE 0x01 /* command done interrupt */ + +/* Fields in the sync_params register */ +#define SYNC_OFF(x) ((x) >> 4) /* offset field */ +#define SYNC_PER(x) ((x) & 0xf) /* period field */ +#define SYNC_PARAMS(o, p) (((o) << 4) | (p)) +#define ASYNC_PARAMS 2 /* sync_params value for async xfers */ + +/* + * Assuming a clock frequency of 50MHz: + * + * The transfer period with SYNC_PER(sync_params) == x + * is (x + 2) * 40ns, except that x == 0 gives 100ns. + * + * The units of the sel_timeout register are 10ms. + */ + + +#endif /* _MESH_H */ |