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/*	$NetBSD: sbicreg.h,v 1.2 1994/10/26 02:04:40 cgd Exp $	*/

/*
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Van Jacobson of Lawrence Berkeley Laboratory.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)scsireg.h	7.3 (Berkeley) 2/5/91
 */

/*
 * AMD AM33C93A SCSI interface hardware description.
 *
 * Using parts of the Mach scsi driver for the 33C93
 */

#define	SBIC_myid	0
#define	SBIC_cdbsize	0
#define	SBIC_control	1
#define	SBIC_timeo	2
#define	SBIC_cdb1	3
#define	SBIC_tsecs	3
#define	SBIC_cdb2	4
#define	SBIC_theads	4
#define	SBIC_cdb3	5
#define	SBIC_tcyl_hi	5
#define	SBIC_cdb4	6
#define	SBIC_tcyl_lo	6
#define	SBIC_cdb5	7
#define	SBIC_addr_hi	7
#define	SBIC_cdb6	8
#define	SBIC_addr_2	8
#define	SBIC_cdb7	9
#define	SBIC_addr_3	9
#define	SBIC_cdb8	10
#define	SBIC_addr_lo	10
#define	SBIC_cdb9	11
#define	SBIC_secno	11
#define	SBIC_cdb10	12
#define	SBIC_headno	12
#define	SBIC_cdb11	13
#define	SBIC_cylno_hi	13
#define	SBIC_cdb12	14
#define	SBIC_cylno_lo	14
#define	SBIC_tlun	15
#define	SBIC_cmd_phase	16
#define	SBIC_syn	17
#define	SBIC_count_hi	18
#define	SBIC_count_med	19
#define	SBIC_count_lo	20
#define	SBIC_selid	21
#define	SBIC_rselid	22
#define	SBIC_csr	23
#define	SBIC_cmd	24
#define	SBIC_data	25
/* sbic_asr is addressed directly */

/*
 *	Register defines
 */

/*
 * Auxiliary Status Register
 */

#define SBIC_ASR_INT		0x80	/* Interrupt pending */
#define SBIC_ASR_LCI		0x40	/* Last command ignored */
#define SBIC_ASR_BSY		0x20	/* Busy, only cmd/data/asr readable */
#define SBIC_ASR_CIP		0x10	/* Busy, cmd unavail also */
#define SBIC_ASR_xxx		0x0c
#define SBIC_ASR_PE		0x02	/* Parity error (even) */
#define SBIC_ASR_DBR		0x01	/* Data Buffer Ready */

/*
 * My ID register, and/or CDB Size
 */

#define SBIC_ID_FS_8_10		0x00	/* Input clock is  8-10 Mhz */
					/* 11 Mhz is invalid */
#define SBIC_ID_FS_12_15	0x40	/* Input clock is 12-15 Mhz */
#define SBIC_ID_FS_16_20	0x80	/* Input clock is 16-20 Mhz */
#define SBIC_ID_EHP		0x10	/* Enable host parity */
#define SBIC_ID_EAF		0x08	/* Enable Advanced Features */
#define SBIC_ID_MASK		0x07
#define SBIC_ID_CBDSIZE_MASK	0x0f	/* if unk SCSI cmd group */

/*
 * Control register
 */

#define SBIC_CTL_DMA		0x80	/* Single byte dma */
#define SBIC_CTL_DBA_DMA	0x40	/* direct buffer acces (bus master)*/
#define SBIC_CTL_BURST_DMA	0x20	/* continuous mode (8237) */
#define SBIC_CTL_NO_DMA		0x00	/* Programmed I/O */
#define SBIC_CTL_HHP		0x10	/* Halt on host parity error */
#define SBIC_CTL_EDI		0x08	/* Ending disconnect interrupt */
#define SBIC_CTL_IDI		0x04	/* Intermediate disconnect interrupt*/
#define SBIC_CTL_HA		0x02	/* Halt on ATN */
#define SBIC_CTL_HSP		0x01	/* Halt on SCSI parity error */

/*
 * Timeout period register
 * [val in msecs, input clk in 0.1 Mhz]
 */

#define	SBIC_TIMEOUT(val,clk)	((((val) * (clk)) / 800) + 1)

/*
 * CDBn registers, note that
 *	cdb11 is used for status byte in target mode (send-status-and-cc)
 *	cdb12 sez if linked command complete, and w/flag if so
 */

/*
 * Target LUN register
 * [holds target status when select-and-xfer]
 */

#define	SBIC_TLUN_VALID	0x80	/* did we receive an Identify msg */
#define	SBIC_TLUN_DOK	0x40	/* Disconnect OK */
#define	SBIC_TLUN_xxx	0x38
#define	SBIC_TLUN_MASK	0x07

/*
 * Command Phase register
 */

#define	SBIC_CPH_MASK	0x7f	/* values/restarts are cmd specific */
#define	SBIC_CPH(p)	((p) & SBIC_CPH_MASK)

/*
 * FIFO register
 */

#define SBIC_FIFO_DEEP	12

/*
 * maximum possible size in TC registers. Since this is 24 bit, it's easy
 */
#define SBIC_TC_MAX	((1 << 24) - 1)

/*
 * Synchronous xfer register
 */

#define	SBIC_SYN_OFF_MASK	0x0f
#define	SBIC_SYN_MAX_OFFSET	SBIC_FIFO_DEEP
#define	SBIC_SYN_PER_MASK	0x70
#define	SBIC_SYN_MIN_PERIOD	2		/* upto 8, encoded as 0 */

#define	SBIC_SYN(o,p) \
    (((o) & SBIC_SYN_OFF_MASK) | (((p) << 4) & SBIC_SYN_PER_MASK))

/*
 * Transfer count register
 * optimal access macros depend on addressing
 */

/*
 * Destination ID (selid) register
 */

#define	SBIC_SID_SCC		0x80	/* Select command chaining (tgt) */
#define	SBIC_SID_DPD		0x40	/* Data phase direction (inittor) */
#define	SBIC_SID_FROM_SCSI	0x40
#define	SBIC_SID_TO_SCSI	0x00
#define	SBIC_SID_xxx		0x38
#define	SBIC_SID_IDMASK		0x07

/*
 * Source ID (rselid) register
 */

#define	SBIC_RID_ER		0x80	/* Enable reselection */
#define	SBIC_RID_ES		0x40	/* Enable selection */
#define	SBIC_RID_DSP		0x20	/* Disable select parity */
#define	SBIC_RID_SIV		0x08	/* Source ID valid */
#define	SBIC_RID_MASK		0x07

/*
 * Status register
 */

#define	SBIC_CSR_CAUSE		0xf0
#define	SBIC_CSR_RESET		0x00	/* chip was reset */
#define	SBIC_CSR_CMD_DONE	0x10	/* cmd completed */
#define	SBIC_CSR_CMD_STOPPED	0x20	/* interrupted or abrted*/
#define	SBIC_CSR_CMD_ERR	0x40	/* end with error */
#define	SBIC_CSR_BUS_SERVICE	0x80	/* REQ pending on the bus */


#define	SBIC_CSR_QUALIFIER	0x0f
/* Reset State Interrupts */
#define	SBIC_CSR_RESET		0x00	/* reset w/advanced features*/
#define	SBIC_CSR_RESET_AM	0x01	/* reset w/advanced features*/
/* Successful Completion Interrupts */
#define	SBIC_CSR_TARGET		0x10	/* reselect complete */
#define	SBIC_CSR_INITIATOR	0x11	/* select complete */
#define	SBIC_CSR_WO_ATN		0x13	/* tgt mode completion */
#define	SBIC_CSR_W_ATN		0x14	/* ditto */
#define	SBIC_CSR_XLATED		0x15	/* translate address cmd */
#define	SBIC_CSR_S_XFERRED	0x16	/* initiator mode completion*/
#define	SBIC_CSR_XFERRED	0x18	/* phase in low bits */
/* Paused or Aborted Interrupts */
#define	SBIC_CSR_MSGIN_W_ACK	0x20	/* (I) msgin, ACK asserted*/
#define	SBIC_CSR_SDP		0x21	/* (I) SDP msg received */
#define	SBIC_CSR_SEL_ABRT	0x22	/* sel/resel aborted */
#define	SBIC_CSR_XFR_PAUSED	0x23	/* (T) no ATN */
#define	SBIC_CSR_XFR_PAUSED_ATN	0x24	/* (T) ATN is asserted */
#define	SBIC_CSR_RSLT_AM	0x27	/* (I) lost selection (AM) */
#define	SBIC_CSR_MIS		0x28	/* (I) xfer aborted, ph mis */
/* Terminated Interrupts */
#define	SBIC_CSR_CMD_INVALID	0x40
#define	SBIC_CSR_DISC		0x41	/* (I) tgt disconnected */
#define	SBIC_CSR_SEL_TIMEO	0x42
#define	SBIC_CSR_PE		0x43	/* parity error */
#define	SBIC_CSR_PE_ATN		0x44	/* ditto, ATN is asserted */
#define	SBIC_CSR_XLATE_TOOBIG	0x45
#define	SBIC_CSR_RSLT_NOAM	0x46	/* (I) lost sel, no AM mode */
#define	SBIC_CSR_BAD_STATUS	0x47	/* status byte was nok */
#define	SBIC_CSR_MIS_1		0x48	/* ph mis, see low bits */
/* Service Required Interrupts */
#define	SBIC_CSR_RSLT_NI	0x80	/* reselected, no ify msg */
#define	SBIC_CSR_RSLT_IFY	0x81	/* ditto, AM mode, got ify */
#define	SBIC_CSR_SLT		0x82	/* selected, no ATN */
#define	SBIC_CSR_SLT_ATN	0x83	/* selected with ATN */
#define	SBIC_CSR_ATN		0x84	/* (T) ATN asserted */
#define	SBIC_CSR_DISC_1		0x85	/* (I) bus is free */
#define	SBIC_CSR_UNK_GROUP	0x87	/* strange CDB1 */
#define	SBIC_CSR_MIS_2		0x88	/* (I) ph mis, see low bits */

#define	SBIC_PHASE(csr)		SCSI_PHASE(csr)

/*
 * Command register (command codes)
 */

#define SBIC_CMD_SBT		0x80	/* Single byte xfer qualifier */
#define	SBIC_CMD_MASK		0x7f

					/* Miscellaneous */
#define SBIC_CMD_RESET		0x00	/* (DTI) lev I */
#define SBIC_CMD_ABORT		0x01	/* (DTI) lev I */
#define SBIC_CMD_DISC		0x04	/* ( TI) lev I */
#define SBIC_CMD_SSCC		0x0d	/* ( TI) lev I */
#define SBIC_CMD_SET_IDI	0x0f	/* (DTI) lev I */
#define SBIC_CMD_XLATE		0x18	/* (DT ) lev II */

					/* Initiator state */
#define SBIC_CMD_SET_ATN	0x02	/* (  I) lev I */
#define SBIC_CMD_CLR_ACK	0x03	/* (  I) lev I */
#define SBIC_CMD_XFER_PAD	0x19	/* (  I) lev II */
#define SBIC_CMD_XFER_INFO	0x20	/* (  I) lev II */

					/* Target state */
#define SBIC_CMD_SND_DISC	0x0e	/* ( T ) lev II */
#define SBIC_CMD_RCV_CMD	0x10	/* ( T ) lev II */
#define SBIC_CMD_RCV_DATA	0x11	/* ( T ) lev II */
#define SBIC_CMD_RCV_MSG_OUT	0x12	/* ( T ) lev II */
#define SBIC_CMD_RCV		0x13	/* ( T ) lev II */
#define SBIC_CMD_SND_STATUS	0x14	/* ( T ) lev II */
#define SBIC_CMD_SND_DATA	0x15	/* ( T ) lev II */
#define SBIC_CMD_SND_MSG_IN	0x16	/* ( T ) lev II */
#define SBIC_CMD_SND		0x17	/* ( T ) lev II */

					/* Disconnected state */
#define SBIC_CMD_RESELECT	0x05	/* (D  ) lev II */
#define SBIC_CMD_SEL_ATN	0x06	/* (D  ) lev II */
#define SBIC_CMD_SEL		0x07	/* (D  ) lev II */
#define SBIC_CMD_SEL_ATN_XFER	0x08	/* (D I) lev II */
#define SBIC_CMD_SEL_XFER	0x09	/* (D I) lev II */
#define SBIC_CMD_RESELECT_RECV	0x0a	/* (DT ) lev II */
#define SBIC_CMD_RESELECT_SEND	0x0b	/* (DT ) lev II */
#define SBIC_CMD_WAIT_SEL_RECV	0x0c	/* (DT ) lev II */

/* approximate, but we won't do SBT on selects */
#define	sbic_isa_select(cmd)	(((cmd) > 0x5) && ((cmd) < 0xa))

#define PAD(n) 	char n;
#define SBIC_MACHINE_DMA_MODE	SBIC_CTL_DMA

typedef struct {
        volatile unsigned char  sbic_asr;	/* r : Aux Status Register */
#define sbic_address sbic_asr			/* w : desired register no */
        /* PAD(pad1); */
        volatile unsigned char  sbic_value;	/* rw: register value */
} sbic_padded_ind_regmap_t;
typedef volatile sbic_padded_ind_regmap_t *sbic_regmap_p;

#define	sbic_read_reg(regs,regno,val) do { \
		(regs)->sbic_address = (regno);	\
		(val) = (regs)->sbic_value;	\
	} while (0)

#define	sbic_write_reg(regs,regno,val)	do { \
		(regs)->sbic_address = (regno);	\
		(regs)->sbic_value = (val);	\
	} while (0)

#define SET_SBIC_myid(regs,val)         sbic_write_reg(regs,SBIC_myid,val)
#define GET_SBIC_myid(regs,val)         sbic_read_reg(regs,SBIC_myid,val)
#define SET_SBIC_cdbsize(regs,val)      sbic_write_reg(regs,SBIC_cdbsize,val)
#define GET_SBIC_cdbsize(regs,val)      sbic_read_reg(regs,SBIC_cdbsize,val)
#define SET_SBIC_control(regs,val)      sbic_write_reg(regs,SBIC_control,val)
#define GET_SBIC_control(regs,val)      sbic_read_reg(regs,SBIC_control,val)
#define SET_SBIC_timeo(regs,val)        sbic_write_reg(regs,SBIC_timeo,val)
#define GET_SBIC_timeo(regs,val)        sbic_read_reg(regs,SBIC_timeo,val)
#define SET_SBIC_cdb1(regs,val)         sbic_write_reg(regs,SBIC_cdb1,val)
#define GET_SBIC_cdb1(regs,val)         sbic_read_reg(regs,SBIC_cdb1,val)
#define SET_SBIC_cdb2(regs,val)         sbic_write_reg(regs,SBIC_cdb2,val)
#define GET_SBIC_cdb2(regs,val)         sbic_read_reg(regs,SBIC_cdb2,val)
#define SET_SBIC_cdb3(regs,val)         sbic_write_reg(regs,SBIC_cdb3,val)
#define GET_SBIC_cdb3(regs,val)         sbic_read_reg(regs,SBIC_cdb3,val)
#define SET_SBIC_cdb4(regs,val)         sbic_write_reg(regs,SBIC_cdb4,val)
#define GET_SBIC_cdb4(regs,val)         sbic_read_reg(regs,SBIC_cdb4,val)
#define SET_SBIC_cdb5(regs,val)         sbic_write_reg(regs,SBIC_cdb5,val)
#define GET_SBIC_cdb5(regs,val)         sbic_read_reg(regs,SBIC_cdb5,val)
#define SET_SBIC_cdb6(regs,val)         sbic_write_reg(regs,SBIC_cdb6,val)
#define GET_SBIC_cdb6(regs,val)         sbic_read_reg(regs,SBIC_cdb6,val)
#define SET_SBIC_cdb7(regs,val)         sbic_write_reg(regs,SBIC_cdb7,val)
#define GET_SBIC_cdb7(regs,val)         sbic_read_reg(regs,SBIC_cdb7,val)
#define SET_SBIC_cdb8(regs,val)         sbic_write_reg(regs,SBIC_cdb8,val)
#define GET_SBIC_cdb8(regs,val)         sbic_read_reg(regs,SBIC_cdb8,val)
#define SET_SBIC_cdb9(regs,val)         sbic_write_reg(regs,SBIC_cdb9,val)
#define GET_SBIC_cdb9(regs,val)         sbic_read_reg(regs,SBIC_cdb9,val)
#define SET_SBIC_cdb10(regs,val)        sbic_write_reg(regs,SBIC_cdb10,val)
#define GET_SBIC_cdb10(regs,val)        sbic_read_reg(regs,SBIC_cdb10,val)
#define SET_SBIC_cdb11(regs,val)        sbic_write_reg(regs,SBIC_cdb11,val)
#define GET_SBIC_cdb11(regs,val)        sbic_read_reg(regs,SBIC_cdb11,val)
#define SET_SBIC_cdb12(regs,val)        sbic_write_reg(regs,SBIC_cdb12,val)
#define GET_SBIC_cdb12(regs,val)        sbic_read_reg(regs,SBIC_cdb12,val)
#define SET_SBIC_tlun(regs,val)         sbic_write_reg(regs,SBIC_tlun,val)
#define GET_SBIC_tlun(regs,val)         sbic_read_reg(regs,SBIC_tlun,val)
#define SET_SBIC_cmd_phase(regs,val)    sbic_write_reg(regs,SBIC_cmd_phase,val)
#define GET_SBIC_cmd_phase(regs,val)    sbic_read_reg(regs,SBIC_cmd_phase,val)
#define SET_SBIC_syn(regs,val)          sbic_write_reg(regs,SBIC_syn,val)
#define GET_SBIC_syn(regs,val)          sbic_read_reg(regs,SBIC_syn,val)
#define SET_SBIC_count_hi(regs,val)     sbic_write_reg(regs,SBIC_count_hi,val)
#define GET_SBIC_count_hi(regs,val)     sbic_read_reg(regs,SBIC_count_hi,val)
#define SET_SBIC_count_med(regs,val)    sbic_write_reg(regs,SBIC_count_med,val)
#define GET_SBIC_count_med(regs,val)    sbic_read_reg(regs,SBIC_count_med,val)
#define SET_SBIC_count_lo(regs,val)     sbic_write_reg(regs,SBIC_count_lo,val)
#define GET_SBIC_count_lo(regs,val)     sbic_read_reg(regs,SBIC_count_lo,val)
#define SET_SBIC_selid(regs,val)        sbic_write_reg(regs,SBIC_selid,val)
#define GET_SBIC_selid(regs,val)        sbic_read_reg(regs,SBIC_selid,val)
#define SET_SBIC_rselid(regs,val)       sbic_write_reg(regs,SBIC_rselid,val)
#define GET_SBIC_rselid(regs,val)       sbic_read_reg(regs,SBIC_rselid,val)
#define SET_SBIC_csr(regs,val)          sbic_write_reg(regs,SBIC_csr,val)
#define GET_SBIC_csr(regs,val)          sbic_read_reg(regs,SBIC_csr,val)
#define SET_SBIC_cmd(regs,val)          sbic_write_reg(regs,SBIC_cmd,val)
#define GET_SBIC_cmd(regs,val)          sbic_read_reg(regs,SBIC_cmd,val)
#define SET_SBIC_data(regs,val)         sbic_write_reg(regs,SBIC_data,val)
#define GET_SBIC_data(regs,val)         sbic_read_reg(regs,SBIC_data,val)

#define SBIC_TC_PUT(regs,val) do { \
	sbic_write_reg(regs,SBIC_count_hi,((val)>>16)); \
	(regs)->sbic_value = (val)>>8; \
	(regs)->sbic_value = (val); \
} while (0)
#define SBIC_TC_GET(regs,val) do { \
	sbic_read_reg(regs,SBIC_count_hi,(val)); \
	(val) = ((val)<<8) | (regs)->sbic_value; \
	(val) = ((val)<<8) | (regs)->sbic_value; \
} while (0)

#define SBIC_LOAD_COMMAND(regs,cmd,cmdsize) do { \
	int n=(cmdsize)-1; \
	char *ptr = (char*)(cmd); \
	sbic_write_reg(regs,SBIC_cdb1,*ptr++); \
	while (n-- > 0) (regs)->sbic_value = *ptr++; \
} while (0)

#define GET_SBIC_asr(regs,val)          (val) = (regs)->sbic_asr

#define WAIT_CIP(regs) do { \
	while ((regs)->sbic_asr & SBIC_ASR_CIP) \
		; \
} while (0)

/* transmit a byte in programmed I/O mode */
#define SEND_BYTE(regs, ch) do { \
  WAIT_CIP(regs); \
  SET_SBIC_cmd(regs, SBIC_CMD_SBT | SBIC_CMD_XFER_INFO); \
  SBIC_WAIT(regs, SBIC_ASR_DBR, 0); \
  SET_SBIC_data(regs, ch); \
  } while (0)

/* receive a byte in programmed I/O mode */
#define RECV_BYTE(regs, ch) do { \
  WAIT_CIP(regs); \
  SET_SBIC_cmd(regs, SBIC_CMD_SBT | SBIC_CMD_XFER_INFO); \
  SBIC_WAIT(regs, SBIC_ASR_DBR, 0); \
  GET_SBIC_data(regs, ch); \
  } while (0)