esp.h

/* $Id: esp.h,v 1.29 2001/12/11 04:55:47 davem Exp $
 * esp.h:  Defines and structures for the Sparc ESP (Enhanced SCSI
 *         Processor) driver under Linux.
 *
 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
 */

#ifndef _SPARC_ESP_H
#define _SPARC_ESP_H

/* For dvma controller register definitions. */
#include <asm/dma.h>

/* The ESP SCSI controllers have their register sets in three
 * "classes":
 *
 * 1) Registers which are both read and write.
 * 2) Registers which are read only.
 * 3) Registers which are write only.
 *
 * Yet, they all live within the same IO space.
 */

/* All the ESP registers are one byte each and are accessed longwords
 * apart with a big-endian ordering to the bytes.
 */
					/* Access    Description              Offset */
#define ESP_TCLOW	0x00UL		/* rw  Low bits of the transfer count 0x00   */
#define ESP_TCMED	0x04UL		/* rw  Mid bits of the transfer count 0x04   */
#define ESP_FDATA	0x08UL		/* rw  FIFO data bits                 0x08   */
#define ESP_CMD		0x0cUL		/* rw  SCSI command bits              0x0c   */
#define ESP_STATUS	0x10UL		/* ro  ESP status register            0x10   */
#define ESP_BUSID	ESP_STATUS	/* wo  Bus ID for select/reselect     0x10   */
#define ESP_INTRPT	0x14UL		/* ro  Kind of interrupt              0x14   */
#define ESP_TIMEO	ESP_INTRPT	/* wo  Timeout value for select/resel 0x14   */
#define ESP_SSTEP	0x18UL		/* ro  Sequence step register         0x18   */
#define ESP_STP		ESP_SSTEP	/* wo  Transfer period per sync       0x18   */
#define ESP_FFLAGS	0x1cUL		/* ro  Bits of current FIFO info      0x1c   */
#define ESP_SOFF	ESP_FFLAGS	/* wo  Sync offset                    0x1c   */
#define ESP_CFG1	0x20UL		/* rw  First configuration register   0x20   */
#define ESP_CFACT	0x24UL		/* wo  Clock conversion factor        0x24   */
#define ESP_STATUS2	ESP_CFACT	/* ro  HME status2 register           0x24   */
#define ESP_CTEST	0x28UL		/* wo  Chip test register             0x28   */
#define ESP_CFG2	0x2cUL		/* rw  Second configuration register  0x2c   */
#define ESP_CFG3	0x30UL		/* rw  Third configuration register   0x30   */
#define ESP_TCHI	0x38UL		/* rw  High bits of transfer count    0x38   */
#define ESP_UID		ESP_TCHI	/* ro  Unique ID code                 0x38   */
#define FAS_RLO		ESP_TCHI	/* rw  HME extended counter           0x38   */
#define ESP_FGRND	0x3cUL		/* rw  Data base for fifo             0x3c   */
#define FAS_RHI		ESP_FGRND	/* rw  HME extended counter           0x3c   */
#define ESP_REG_SIZE	0x40UL

/* Various revisions of the ESP board. */
enum esp_rev {
	esp100     = 0x00,  /* NCR53C90 - very broken */
	esp100a    = 0x01,  /* NCR53C90A */
	esp236     = 0x02,
	fas236     = 0x03,
	fas100a    = 0x04,
	fast       = 0x05,
	fashme     = 0x06,
	espunknown = 0x07
};

/* We allocate one of these for each scsi device and attach it to
 * SDptr->hostdata for use in the driver
 */
struct esp_device {
  unsigned char sync_min_period;
  unsigned char sync_max_offset;
  unsigned sync:1;
  unsigned wide:1;
  unsigned disconnect:1;
};

struct scsi_cmnd;

/* We get one of these for each ESP probed. */
struct esp {
	void __iomem		*eregs;		/* ESP controller registers */
	void __iomem		*dregs;		/* DMA controller registers */
	struct sbus_dma		*dma;		/* DMA controller sw state */
	struct Scsi_Host	*ehost;		/* Backpointer to SCSI Host */
	struct sbus_dev		*sdev;		/* Pointer to SBus entry */

	/* ESP Configuration Registers */
	u8			config1;	/* Copy of the 1st config register */
	u8			config2;	/* Copy of the 2nd config register */
	u8			config3[16];	/* Copy of the 3rd config register */

	/* The current command we are sending to the ESP chip.  This esp_command
	 * ptr needs to be mapped in DVMA area so we can send commands and read
	 * from the ESP fifo without burning precious CPU cycles.  Programmed I/O
	 * sucks when we have the DVMA to do it for us.  The ESP is stupid and will
	 * only send out 6, 10, and 12 byte SCSI commands, others we need to send
	 * one byte at a time.  esp_slowcmd being set says that we are doing one
	 * of the command types ESP doesn't understand, esp_scmdp keeps track of
	 * which byte we are sending, esp_scmdleft says how many bytes to go.
	 */
	volatile u8		*esp_command;    /* Location of command (CPU view)  */
	__u32			esp_command_dvma;/* Location of command (DVMA view) */
	unsigned char		esp_clen;	 /* Length of this command */
	unsigned char		esp_slowcmd;
	unsigned char		*esp_scmdp;
	unsigned char		esp_scmdleft;

	/* The following are used to determine the cause of an IRQ. Upon every
	 * IRQ entry we synchronize these with the hardware registers.
	 */
	u8			ireg;		/* Copy of ESP interrupt register */
	u8			sreg;		/* Copy of ESP status register */
	u8			seqreg;		/* Copy of ESP sequence step register */
	u8			sreg2;		/* Copy of HME status2 register */

	/* To save register writes to the ESP, which can be expensive, we
	 * keep track of the previous value that various registers had for
	 * the last target we connected to.  If they are the same for the
	 * current target, we skip the register writes as they are not needed.
	 */
	u8			prev_soff, prev_stp;
	u8			prev_cfg3, __cache_pad;

	/* We also keep a cache of the previous FAS/HME DMA CSR register value.  */
	u32			prev_hme_dmacsr;

	/* The HME is the biggest piece of shit I have ever seen. */
	u8			hme_fifo_workaround_buffer[16 * 2];
	u8			hme_fifo_workaround_count;

	/* For each target we keep track of save/restore data
	 * pointer information.  This needs to be updated majorly
	 * when we add support for tagged queueing.  -DaveM
	 */
	struct esp_pointers {
		char			*saved_ptr;
		struct scatterlist	*saved_buffer;
		int			saved_this_residual;
		int			saved_buffers_residual;
	} data_pointers[16] /*XXX [MAX_TAGS_PER_TARGET]*/;

	/* Clock periods, frequencies, synchronization, etc. */
	unsigned int		cfreq;		/* Clock frequency in HZ */
	unsigned int		cfact;		/* Clock conversion factor */
	unsigned int		raw_cfact;	/* Raw copy from probing */
	unsigned int		ccycle;		/* One ESP clock cycle */
	unsigned int		ctick;		/* One ESP clock time */
	unsigned int		radelay;	/* FAST chip req/ack delay */
	unsigned int		neg_defp;	/* Default negotiation period */
	unsigned int		sync_defp;	/* Default sync transfer period */
	unsigned int		max_period;	/* longest our period can be */
	unsigned int		min_period;	/* shortest period we can withstand */

	struct esp		*next;		/* Next ESP we probed or NULL */
	char			prom_name[64];	/* Name of ESP device from prom */
	int			prom_node;	/* Prom node where ESP found */
	int			esp_id;		/* Unique per-ESP ID number */

	/* For slow to medium speed input clock rates we shoot for 5mb/s,
	 * but for high input clock rates we try to do 10mb/s although I
	 * don't think a transfer can even run that fast with an ESP even
	 * with DMA2 scatter gather pipelining.
	 */
#define SYNC_DEFP_SLOW            0x32   /* 5mb/s  */
#define SYNC_DEFP_FAST            0x19   /* 10mb/s */

	unsigned int		snip;		/* Sync. negotiation in progress */
	unsigned int		wnip;		/* WIDE negotiation in progress */
	unsigned int		targets_present;/* targets spoken to before */

	int		current_transfer_size;	/* Set at beginning of data dma */

	u8			espcmdlog[32];	/* Log of current esp cmds sent. */
	u8			espcmdent;	/* Current entry in esp cmd log. */

	/* Misc. info about this ESP */
	enum esp_rev		erev;		/* ESP revision */
	int			irq;		/* SBus IRQ for this ESP */
	int			scsi_id;	/* Who am I as initiator? */
	int			scsi_id_mask;	/* Bitmask of 'me'. */
	int			diff;		/* Differential SCSI bus? */
	int			bursts;		/* Burst sizes our DVMA supports */

	/* Our command queues, only one cmd lives in the current_SC queue. */
	struct scsi_cmnd	*issue_SC;	/* Commands to be issued */
	struct scsi_cmnd	*current_SC;	/* Who is currently working the bus */
	struct scsi_cmnd	*disconnected_SC;/* Commands disconnected from the bus */

	/* Message goo */
	u8			cur_msgout[16];
	u8			cur_msgin[16];
	u8			prevmsgout, prevmsgin;
	u8			msgout_len, msgin_len;
	u8			msgout_ctr, msgin_ctr;

	/* States that we cannot keep in the per cmd structure because they
	 * cannot be assosciated with any specific command.
	 */
	u8			resetting_bus;
	wait_queue_head_t	reset_queue;
};

/* Bitfield meanings for the above registers. */

/* ESP config reg 1, read-write, found on all ESP chips */
#define ESP_CONFIG1_ID        0x07             /* My BUS ID bits */
#define ESP_CONFIG1_CHTEST    0x08             /* Enable ESP chip tests */
#define ESP_CONFIG1_PENABLE   0x10             /* Enable parity checks */
#define ESP_CONFIG1_PARTEST   0x20             /* Parity test mode enabled? */
#define ESP_CONFIG1_SRRDISAB  0x40             /* Disable SCSI reset reports */
#define ESP_CONFIG1_SLCABLE   0x80             /* Enable slow cable mode */

/* ESP config reg 2, read-write, found only on esp100a+esp200+esp236 chips */
#define ESP_CONFIG2_DMAPARITY 0x01             /* enable DMA Parity (200,236) */
#define ESP_CONFIG2_REGPARITY 0x02             /* enable reg Parity (200,236) */
#define ESP_CONFIG2_BADPARITY 0x04             /* Bad parity target abort  */
#define ESP_CONFIG2_SCSI2ENAB 0x08             /* Enable SCSI-2 features (tmode only) */
#define ESP_CONFIG2_HI        0x10             /* High Impedance DREQ ???  */
#define ESP_CONFIG2_HMEFENAB  0x10             /* HME features enable */
#define ESP_CONFIG2_BCM       0x20             /* Enable byte-ctrl (236)   */
#define ESP_CONFIG2_DISPINT   0x20             /* Disable pause irq (hme) */
#define ESP_CONFIG2_FENAB     0x40             /* Enable features (fas100,esp216)      */
#define ESP_CONFIG2_SPL       0x40             /* Enable status-phase latch (esp236)   */
#define ESP_CONFIG2_MKDONE    0x40             /* HME magic feature */
#define ESP_CONFIG2_HME32     0x80             /* HME 32 extended */
#define ESP_CONFIG2_MAGIC     0xe0             /* Invalid bits... */

/* ESP config register 3 read-write, found only esp236+fas236+fas100a+hme chips */
#define ESP_CONFIG3_FCLOCK    0x01             /* FAST SCSI clock rate (esp100a/hme) */
#define ESP_CONFIG3_TEM       0x01             /* Enable thresh-8 mode (esp/fas236)  */
#define ESP_CONFIG3_FAST      0x02             /* Enable FAST SCSI     (esp100a/hme) */
#define ESP_CONFIG3_ADMA      0x02             /* Enable alternate-dma (esp/fas236)  */
#define ESP_CONFIG3_TENB      0x04             /* group2 SCSI2 support (esp100a/hme) */
#define ESP_CONFIG3_SRB       0x04             /* Save residual byte   (esp/fas236)  */
#define ESP_CONFIG3_TMS       0x08             /* Three-byte msg's ok  (esp100a/hme) */
#define ESP_CONFIG3_FCLK      0x08             /* Fast SCSI clock rate (esp/fas236)  */
#define ESP_CONFIG3_IDMSG     0x10             /* ID message checking  (esp100a/hme) */
#define ESP_CONFIG3_FSCSI     0x10             /* Enable FAST SCSI     (esp/fas236)  */
#define ESP_CONFIG3_GTM       0x20             /* group2 SCSI2 support (esp/fas236)  */
#define ESP_CONFIG3_IDBIT3    0x20             /* Bit 3 of HME SCSI-ID (hme)         */
#define ESP_CONFIG3_TBMS      0x40             /* Three-byte msg's ok  (esp/fas236)  */
#define ESP_CONFIG3_EWIDE     0x40             /* Enable Wide-SCSI     (hme)         */
#define ESP_CONFIG3_IMS       0x80             /* ID msg chk'ng        (esp/fas236)  */
#define ESP_CONFIG3_OBPUSH    0x80             /* Push odd-byte to dma (hme)         */

/* ESP command register read-write */
/* Group 1 commands:  These may be sent at any point in time to the ESP
 *                    chip.  None of them can generate interrupts 'cept
 *                    the "SCSI bus reset" command if you have not disabled
 *                    SCSI reset interrupts in the config1 ESP register.
 */
#define ESP_CMD_NULL          0x00             /* Null command, ie. a nop */
#define ESP_CMD_FLUSH         0x01             /* FIFO Flush */
#define ESP_CMD_RC            0x02             /* Chip reset */
#define ESP_CMD_RS            0x03             /* SCSI bus reset */

/* Group 2 commands:  ESP must be an initiator and connected to a target
 *                    for these commands to work.
 */
#define ESP_CMD_TI            0x10             /* Transfer Information */
#define ESP_CMD_ICCSEQ        0x11             /* Initiator cmd complete sequence */
#define ESP_CMD_MOK           0x12             /* Message okie-dokie */
#define ESP_CMD_TPAD          0x18             /* Transfer Pad */
#define ESP_CMD_SATN          0x1a             /* Set ATN */
#define ESP_CMD_RATN          0x1b             /* De-assert ATN */

/* Group 3 commands:  ESP must be in the MSGOUT or MSGIN state and be connected
 *                    to a target as the initiator for these commands to work.
 */
#define ESP_CMD_SMSG          0x20             /* Send message */
#define ESP_CMD_SSTAT         0x21             /* Send status */
#define ESP_CMD_SDATA         0x22             /* Send data */
#define ESP_CMD_DSEQ          0x23             /* Discontinue Sequence */
#define ESP_CMD_TSEQ          0x24             /* Terminate Sequence */
#define ESP_CMD_TCCSEQ        0x25             /* Target cmd cmplt sequence */
#define ESP_CMD_DCNCT         0x27             /* Disconnect */
#define ESP_CMD_RMSG          0x28             /* Receive Message */
#define ESP_CMD_RCMD          0x29             /* Receive Command */
#define ESP_CMD_RDATA         0x2a             /* Receive Data */
#define ESP_CMD_RCSEQ         0x2b             /* Receive cmd sequence */

/* Group 4 commands:  The ESP must be in the disconnected state and must
 *                    not be connected to any targets as initiator for
 *                    these commands to work.
 */
#define ESP_CMD_RSEL          0x40             /* Reselect */
#define ESP_CMD_SEL           0x41             /* Select w/o ATN */
#define ESP_CMD_SELA          0x42             /* Select w/ATN */
#define ESP_CMD_SELAS         0x43             /* Select w/ATN & STOP */
#define ESP_CMD_ESEL          0x44             /* Enable selection */
#define ESP_CMD_DSEL          0x45             /* Disable selections */
#define ESP_CMD_SA3           0x46             /* Select w/ATN3 */
#define ESP_CMD_RSEL3         0x47             /* Reselect3 */

/* This bit enables the ESP's DMA on the SBus */
#define ESP_CMD_DMA           0x80             /* Do DMA? */


/* ESP status register read-only */
#define ESP_STAT_PIO          0x01             /* IO phase bit */
#define ESP_STAT_PCD          0x02             /* CD phase bit */
#define ESP_STAT_PMSG         0x04             /* MSG phase bit */
#define ESP_STAT_PMASK        0x07             /* Mask of phase bits */
#define ESP_STAT_TDONE        0x08             /* Transfer Completed */
#define ESP_STAT_TCNT         0x10             /* Transfer Counter Is Zero */
#define ESP_STAT_PERR         0x20             /* Parity error */
#define ESP_STAT_SPAM         0x40             /* Real bad error */
/* This indicates the 'interrupt pending' condition on esp236, it is a reserved
 * bit on other revs of the ESP.
 */
#define ESP_STAT_INTR         0x80             /* Interrupt */

/* HME only: status 2 register */
#define ESP_STAT2_SCHBIT      0x01 /* Upper bits 3-7 of sstep enabled */
#define ESP_STAT2_FFLAGS      0x02 /* The fifo flags are now latched */
#define ESP_STAT2_XCNT        0x04 /* The transfer counter is latched */
#define ESP_STAT2_CREGA       0x08 /* The command reg is active now */
#define ESP_STAT2_WIDE        0x10 /* Interface on this adapter is wide */
#define ESP_STAT2_F1BYTE      0x20 /* There is one byte at top of fifo */
#define ESP_STAT2_FMSB        0x40 /* Next byte in fifo is most significant */
#define ESP_STAT2_FEMPTY      0x80 /* FIFO is empty */

/* The status register can be masked with ESP_STAT_PMASK and compared
 * with the following values to determine the current phase the ESP
 * (at least thinks it) is in.  For our purposes we also add our own
 * software 'done' bit for our phase management engine.
 */
#define ESP_DOP   (0)                                       /* Data Out  */
#define ESP_DIP   (ESP_STAT_PIO)                            /* Data In   */
#define ESP_CMDP  (ESP_STAT_PCD)                            /* Command   */
#define ESP_STATP (ESP_STAT_PCD|ESP_STAT_PIO)               /* Status    */
#define ESP_MOP   (ESP_STAT_PMSG|ESP_STAT_PCD)              /* Message Out */
#define ESP_MIP   (ESP_STAT_PMSG|ESP_STAT_PCD|ESP_STAT_PIO) /* Message In */

/* ESP interrupt register read-only */
#define ESP_INTR_S            0x01             /* Select w/o ATN */
#define ESP_INTR_SATN         0x02             /* Select w/ATN */
#define ESP_INTR_RSEL         0x04             /* Reselected */
#define ESP_INTR_FDONE        0x08             /* Function done */
#define ESP_INTR_BSERV        0x10             /* Bus service */
#define ESP_INTR_DC           0x20             /* Disconnect */
#define ESP_INTR_IC           0x40             /* Illegal command given */
#define ESP_INTR_SR           0x80             /* SCSI bus reset detected */

/* Interrupt status macros */
#define ESP_SRESET_IRQ(esp)  ((esp)->intreg & (ESP_INTR_SR))
#define ESP_ILLCMD_IRQ(esp)  ((esp)->intreg & (ESP_INTR_IC))
#define ESP_SELECT_WITH_ATN_IRQ(esp)     ((esp)->intreg & (ESP_INTR_SATN))
#define ESP_SELECT_WITHOUT_ATN_IRQ(esp)  ((esp)->intreg & (ESP_INTR_S))
#define ESP_SELECTION_IRQ(esp)  ((ESP_SELECT_WITH_ATN_IRQ(esp)) ||         \
				 (ESP_SELECT_WITHOUT_ATN_IRQ(esp)))
#define ESP_RESELECTION_IRQ(esp)         ((esp)->intreg & (ESP_INTR_RSEL))

/* ESP sequence step register read-only */
#define ESP_STEP_VBITS        0x07             /* Valid bits */
#define ESP_STEP_ASEL         0x00             /* Selection&Arbitrate cmplt */
#define ESP_STEP_SID          0x01             /* One msg byte sent */
#define ESP_STEP_NCMD         0x02             /* Was not in command phase */
#define ESP_STEP_PPC          0x03             /* Early phase chg caused cmnd
                                                * bytes to be lost
                                                */
#define ESP_STEP_FINI4        0x04             /* Command was sent ok */

/* Ho hum, some ESP's set the step register to this as well... */
#define ESP_STEP_FINI5        0x05
#define ESP_STEP_FINI6        0x06
#define ESP_STEP_FINI7        0x07

/* ESP chip-test register read-write */
#define ESP_TEST_TARG         0x01             /* Target test mode */
#define ESP_TEST_INI          0x02             /* Initiator test mode */
#define ESP_TEST_TS           0x04             /* Tristate test mode */

/* ESP unique ID register read-only, found on fas236+fas100a only */
#define ESP_UID_F100A         0x00             /* ESP FAS100A  */
#define ESP_UID_F236          0x02             /* ESP FAS236   */
#define ESP_UID_REV           0x07             /* ESP revision */
#define ESP_UID_FAM           0xf8             /* ESP family   */

/* ESP fifo flags register read-only */
/* Note that the following implies a 16 byte FIFO on the ESP. */
#define ESP_FF_FBYTES         0x1f             /* Num bytes in FIFO */
#define ESP_FF_ONOTZERO       0x20             /* offset ctr not zero (esp100) */
#define ESP_FF_SSTEP          0xe0             /* Sequence step */

/* ESP clock conversion factor register write-only */
#define ESP_CCF_F0            0x00             /* 35.01MHz - 40MHz */
#define ESP_CCF_NEVER         0x01             /* Set it to this and die */
#define ESP_CCF_F2            0x02             /* 10MHz */
#define ESP_CCF_F3            0x03             /* 10.01MHz - 15MHz */
#define ESP_CCF_F4            0x04             /* 15.01MHz - 20MHz */
#define ESP_CCF_F5            0x05             /* 20.01MHz - 25MHz */
#define ESP_CCF_F6            0x06             /* 25.01MHz - 30MHz */
#define ESP_CCF_F7            0x07             /* 30.01MHz - 35MHz */

/* HME only... */
#define ESP_BUSID_RESELID     0x10
#define ESP_BUSID_CTR32BIT    0x40

#define ESP_BUS_TIMEOUT        275             /* In milli-seconds */
#define ESP_TIMEO_CONST       8192
#define ESP_NEG_DEFP(mhz, cfact) \
        ((ESP_BUS_TIMEOUT * ((mhz) / 1000)) / (8192 * (cfact)))
#define ESP_MHZ_TO_CYCLE(mhertz)  ((1000000000) / ((mhertz) / 1000))
#define ESP_TICK(ccf, cycle)  ((7682 * (ccf) * (cycle) / 1000))

#endif /* !(_SPARC_ESP_H) */