aic79xx_core.c

这个linux源代码是很全面的~基本完整了~使用c编译的~由于时间问题我没有亲自测试~但就算用来做参考资料也是非常好的

		for (i = 0; i < ahd->num_critical_sections; i++, cs++) {
			
			if (cs->begin < seqaddr && cs->end >= seqaddr)
				break;
		}

		if (i == ahd->num_critical_sections)
			break;

		if (steps > AHD_MAX_STEPS) {
			printf("%s: Infinite loop in critical section\n",
			       ahd_name(ahd));
			ahd_dump_card_state(ahd);
			panic("critical section loop");
		}

		steps++;
		if (stepping == FALSE) {

			/*
			 * Disable all interrupt sources so that the
			 * sequencer will not be stuck by a pausing
			 * interrupt condition while we attempt to
			 * leave a critical section.
			 */
			ahd_set_modes(ahd, AHD_MODE_CFG, AHD_MODE_CFG);
			simode0 = ahd_inb(ahd, SIMODE0);
			simode3 = ahd_inb(ahd, SIMODE3);
			lqimode0 = ahd_inb(ahd, LQIMODE0);
			lqimode1 = ahd_inb(ahd, LQIMODE1);
			lqomode0 = ahd_inb(ahd, LQOMODE0);
			lqomode1 = ahd_inb(ahd, LQOMODE1);
			ahd_outb(ahd, SIMODE0, 0);
			ahd_outb(ahd, SIMODE3, 0);
			ahd_outb(ahd, LQIMODE0, 0);
			ahd_outb(ahd, LQIMODE1, 0);
			ahd_outb(ahd, LQOMODE0, 0);
			ahd_outb(ahd, LQOMODE1, 0);
			ahd_set_modes(ahd, AHD_MODE_SCSI, AHD_MODE_SCSI);
			simode1 = ahd_inb(ahd, SIMODE1);
			ahd_outb(ahd, SIMODE1, 0);
			ahd_outb(ahd, CLRINT, CLRSCSIINT);
			ahd_outb(ahd, SEQCTL0, ahd_inb(ahd, SEQCTL0) | STEP);
			stepping = TRUE;
		}
		ahd_set_modes(ahd, ahd->saved_src_mode, ahd->saved_dst_mode);
		ahd_outb(ahd, HCNTRL, ahd->unpause);
		do {
			ahd_delay(200);
		} while (!ahd_is_paused(ahd));
		ahd_update_modes(ahd);
	}
	if (stepping) {
		ahd_set_modes(ahd, AHD_MODE_CFG, AHD_MODE_CFG);
		ahd_outb(ahd, SIMODE0, simode0);
		ahd_outb(ahd, SIMODE3, simode3);
		ahd_outb(ahd, LQIMODE0, lqimode0);
		ahd_outb(ahd, LQIMODE1, lqimode1);
		ahd_outb(ahd, LQOMODE0, lqomode0);
		ahd_outb(ahd, LQOMODE1, lqomode1);
		ahd_set_modes(ahd, AHD_MODE_SCSI, AHD_MODE_SCSI);
		ahd_outb(ahd, SIMODE1, simode1);
		ahd_outb(ahd, SEQCTL0, ahd_inb(ahd, SEQCTL0) & ~STEP);
	}
	ahd_restore_modes(ahd, saved_modes);
}

/*
 * Clear any pending interrupt status.
 */
void
ahd_clear_intstat(struct ahd_softc *ahd)
{
	/* Clear any interrupt conditions this may have caused */
	ahd_outb(ahd, CLRSINT1, CLRSELTIMEO|CLRATNO|CLRSCSIRSTI
				|CLRBUSFREE|CLRSCSIPERR|CLRREQINIT);
	ahd_outb(ahd, CLRSINT0, CLRSELDO|CLRSELDI|CLRSELINGO|CLRIOERR);
	ahd_outb(ahd, CLRINT, CLRSCSIINT);
}

/**************************** Debugging Routines ******************************/
#ifdef AHD_DEBUG
uint32_t ahd_debug = AHD_DEBUG;
#endif
void
ahd_print_scb(struct scb *scb)
{
	struct hardware_scb *hscb;
	int i;

	hscb = scb->hscb;
	printf("scb:%p control:0x%x scsiid:0x%x lun:%d cdb_len:%d\n",
	       (void *)scb,
	       hscb->control,
	       hscb->scsiid,
	       hscb->lun,
	       hscb->cdb_len);
	printf("Shared Data: ");
	for (i = 0; i < sizeof(hscb->shared_data.idata.cdb); i++)
		printf("%#02x", hscb->shared_data.idata.cdb[i]);
	printf("        dataptr:%#x%x datacnt:%#x sgptr:%#x tag:%#x\n",
	       (uint32_t)((ahd_le64toh(hscb->dataptr) >> 32) & 0xFFFFFFFF),
	       (uint32_t)(ahd_le64toh(hscb->dataptr) & 0xFFFFFFFF),
	       ahd_le32toh(hscb->datacnt),
	       ahd_le32toh(hscb->sgptr),
	       SCB_GET_TAG(scb));
	ahd_dump_sglist(scb);
}

void
ahd_dump_sglist(struct scb *scb)
{
	int i;

	if (scb->sg_count > 0) {
		if ((scb->ahd_softc->flags & AHD_64BIT_ADDRESSING) != 0) {
			struct ahd_dma64_seg *sg_list;

			sg_list = (struct ahd_dma64_seg*)scb->sg_list;
			for (i = 0; i < scb->sg_count; i++) {
				uint64_t addr;

				addr = ahd_le64toh(sg_list[i].addr);
				printf("sg[%d] - Addr 0x%x%x : Length %d\n",
				       i,
				       (uint32_t)((addr >> 32) & 0xFFFFFFFF),
				       (uint32_t)(addr & 0xFFFFFFFF),
				       ahd_le32toh(sg_list[i].len));
			}
		} else {
			struct ahd_dma_seg *sg_list;

			sg_list = (struct ahd_dma_seg*)scb->sg_list;
			for (i = 0; i < scb->sg_count; i++) {
				printf("sg[%d] - Addr 0x%x%x : Length %d\n",
				       i,
				       (ahd_le32toh(sg_list[i].len) >> 24
				        & SG_HIGH_ADDR_BITS),
				       ahd_le32toh(sg_list[i].addr),
				       ahd_le32toh(sg_list[i].len)
				       & AHD_SG_LEN_MASK);
			}
		}
	}
}

/************************* Transfer Negotiation *******************************/
/*
 * Allocate per target mode instance (ID we respond to as a target)
 * transfer negotiation data structures.
 */
static struct ahd_tmode_tstate *
ahd_alloc_tstate(struct ahd_softc *ahd, u_int scsi_id, char channel)
{
	struct ahd_tmode_tstate *master_tstate;
	struct ahd_tmode_tstate *tstate;
	int i;

	master_tstate = ahd->enabled_targets[ahd->our_id];
	if (ahd->enabled_targets[scsi_id] != NULL
	 && ahd->enabled_targets[scsi_id] != master_tstate)
		panic("%s: ahd_alloc_tstate - Target already allocated",
		      ahd_name(ahd));
	tstate = malloc(sizeof(*tstate), M_DEVBUF, M_NOWAIT);
	if (tstate == NULL)
		return (NULL);

	/*
	 * If we have allocated a master tstate, copy user settings from
	 * the master tstate (taken from SRAM or the EEPROM) for this
	 * channel, but reset our current and goal settings to async/narrow
	 * until an initiator talks to us.
	 */
	if (master_tstate != NULL) {
		memcpy(tstate, master_tstate, sizeof(*tstate));
		memset(tstate->enabled_luns, 0, sizeof(tstate->enabled_luns));
		for (i = 0; i < 16; i++) {
			memset(&tstate->transinfo[i].curr, 0,
			      sizeof(tstate->transinfo[i].curr));
			memset(&tstate->transinfo[i].goal, 0,
			      sizeof(tstate->transinfo[i].goal));
		}
	} else
		memset(tstate, 0, sizeof(*tstate));
	ahd->enabled_targets[scsi_id] = tstate;
	return (tstate);
}

#ifdef AHD_TARGET_MODE
/*
 * Free per target mode instance (ID we respond to as a target)
 * transfer negotiation data structures.
 */
static void
ahd_free_tstate(struct ahd_softc *ahd, u_int scsi_id, char channel, int force)
{
	struct ahd_tmode_tstate *tstate;

	/*
	 * Don't clean up our "master" tstate.
	 * It has our default user settings.
	 */
	if (scsi_id == ahd->our_id
	 && force == FALSE)
		return;

	tstate = ahd->enabled_targets[scsi_id];
	if (tstate != NULL)
		free(tstate, M_DEVBUF);
	ahd->enabled_targets[scsi_id] = NULL;
}
#endif

/*
 * Called when we have an active connection to a target on the bus,
 * this function finds the nearest period to the input period limited
 * by the capabilities of the bus connectivity of and sync settings for
 * the target.
 */
void
ahd_devlimited_syncrate(struct ahd_softc *ahd,
			struct ahd_initiator_tinfo *tinfo,
			u_int *period, u_int *ppr_options, role_t role)
{
	struct	ahd_transinfo *transinfo;
	u_int	maxsync;

	if ((ahd_inb(ahd, SBLKCTL) & ENAB40) != 0
	 && (ahd_inb(ahd, SSTAT2) & EXP_ACTIVE) == 0) {
		maxsync = AHD_SYNCRATE_PACED;
	} else {
		maxsync = AHD_SYNCRATE_ULTRA;
		/* Can't do DT related options on an SE bus */
		*ppr_options &= MSG_EXT_PPR_QAS_REQ;
	}
	/*
	 * Never allow a value higher than our current goal
	 * period otherwise we may allow a target initiated
	 * negotiation to go above the limit as set by the
	 * user.  In the case of an initiator initiated
	 * sync negotiation, we limit based on the user
	 * setting.  This allows the system to still accept
	 * incoming negotiations even if target initiated
	 * negotiation is not performed.
	 */
	if (role == ROLE_TARGET)
		transinfo = &tinfo->user;
	else 
		transinfo = &tinfo->goal;
	*ppr_options &= (transinfo->ppr_options|MSG_EXT_PPR_PCOMP_EN);
	if (transinfo->period == 0) {
		*period = 0;
		*ppr_options = 0;
	} else {
		*period = MAX(*period, transinfo->period);
		ahd_find_syncrate(ahd, period, ppr_options, maxsync);
	}
}

/*
 * Look up the valid period to SCSIRATE conversion in our table.
 * Return the period and offset that should be sent to the target
 * if this was the beginning of an SDTR.
 */
void
ahd_find_syncrate(struct ahd_softc *ahd, u_int *period,
		  u_int *ppr_options, u_int maxsync)
{
	/* Skip all PACED only entries if IU is not available */
	if ((*ppr_options & MSG_EXT_PPR_IU_REQ) == 0
	 && maxsync < AHD_SYNCRATE_DT)
		maxsync = AHD_SYNCRATE_DT;

	/* Skip all DT only entries if DT is not available */
	if ((*ppr_options & MSG_EXT_PPR_DT_REQ) == 0
	 && maxsync < AHD_SYNCRATE_ULTRA2)
		maxsync = AHD_SYNCRATE_ULTRA2;
	
	if (*period < maxsync)
		*period = maxsync;

	if ((*ppr_options & MSG_EXT_PPR_DT_REQ) != 0
	 && *period > AHD_SYNCRATE_MIN_DT)
		*ppr_options &= ~MSG_EXT_PPR_DT_REQ;
		
	if (*period > AHD_SYNCRATE_MIN)
		*period = 0;

	/* Honor PPR option conformance rules. */
	if ((*ppr_options & MSG_EXT_PPR_IU_REQ) == 0)
		*ppr_options &= (MSG_EXT_PPR_DT_REQ|MSG_EXT_PPR_QAS_REQ);

	if ((*ppr_options & MSG_EXT_PPR_DT_REQ) == 0)
		*ppr_options &= MSG_EXT_PPR_QAS_REQ;
}

/*
 * Truncate the given synchronous offset to a value the
 * current adapter type and syncrate are capable of.
 */
void
ahd_validate_offset(struct ahd_softc *ahd,
		    struct ahd_initiator_tinfo *tinfo,
		    u_int period, u_int *offset, int wide,
		    role_t role)
{
	u_int maxoffset;

	/* Limit offset to what we can do */
	if (period == 0)
		maxoffset = 0;
	else if (period <= AHD_SYNCRATE_PACED)
		maxoffset = MAX_OFFSET_PACED;
	else
		maxoffset = MAX_OFFSET;
	*offset = MIN(*offset, maxoffset);
	if (tinfo != NULL) {
		if (role == ROLE_TARGET)
			*offset = MIN(*offset, tinfo->user.offset);
		else
			*offset = MIN(*offset, tinfo->goal.offset);
	}
}

/*
 * Truncate the given transfer width parameter to a value the
 * current adapter type is capable of.
 */
void
ahd_validate_width(struct ahd_softc *ahd, struct ahd_initiator_tinfo *tinfo,
		   u_int *bus_width, role_t role)
{
	switch (*bus_width) {
	default:
		if (ahd->features & AHD_WIDE) {
			/* Respond Wide */
			*bus_width = MSG_EXT_WDTR_BUS_16_BIT;
			break;
		}
		/* FALLTHROUGH */
	case MSG_EXT_WDTR_BUS_8_BIT:
		*bus_width = MSG_EXT_WDTR_BUS_8_BIT;
		break;
	}
	if (tinfo != NULL) {
		if (role == ROLE_TARGET)
			*bus_width = MIN(tinfo->user.width, *bus_width);
		else
			*bus_width = MIN(tinfo->goal.width, *bus_width);
	}
}

/*
 * Update the bitmask of targets for which the controller should
 * negotiate with at the next convenient oportunity.  This currently
 * means the next time we send the initial identify messages for
 * a new transaction.
 */
int
ahd_update_neg_request(struct ahd_softc *ahd, struct ahd_devinfo *devinfo,
		       struct ahd_tmode_tstate *tstate,
		       struct ahd_initiator_tinfo *tinfo, int force)
{
	u_int auto_negotiate_orig;

	auto_negotiate_orig = tstate->auto_negotiate;
	if (tinfo->curr.period != tinfo->goal.period
	 || tinfo->curr.width != tinfo->goal.width
	 || tinfo->curr.offset != tinfo->goal.offset
	 || tinfo->curr.ppr_options != tinfo->goal.ppr_options
	 || (force
	  && (tinfo->goal.period != 0
	   || tinfo->goal.width != MSG_EXT_WDTR_BUS_8_BIT
	   || tinfo->goal.ppr_options != 0)))
		tstate->auto_negotiate |= devinfo->target_mask;
	else
		tstate->auto_negotiate &= ~devinfo->target_mask;

	return (auto_negotiate_orig != tstate->auto_negotiate);
}

/*
 * Update the user/goal/curr tables of synchronous negotiation
 * parameters as well as, in the case of a current or active update,
 * any data structures on the host controller.  In the case of an
 * active update, the specified target is currently talking to us on
 * the bus, so the transfer parameter update must take effect
 * immediately.
 */
void
ahd_set_syncrate(struct ahd_softc *ahd, struct ahd_devinfo *devinfo,
		 u_int period, u_int offset, u_int ppr_options,
		 u_int type, int paused)
{
	struct	ahd_initiator_tinfo *tinfo;
	struct	ahd_tmode_tstate *tstate;
	u_int	old_period;
	u_int	old_offset;
	u_int	old_ppr;
	int	active;
	int	update_needed;

	active = (type & AHD_TRANS_ACTIVE) == AHD_TRANS_ACTIVE;
	update_needed = 0;

	if (period == 0 || offset == 0) {
		period = 0;
		offset = 0;
	}

	tinfo = ahd_fetch_transinfo(ahd, devinfo->channel, devinfo->our_scsiid,
				    devinfo->target, &tstate);

	if ((type & AHD_TRANS_USER) != 0) {
		tinfo->user.period = period;
		tinfo->user.offset = offset;
		tinfo->user.ppr_options = ppr_options;
	}

	if ((type & AHD_TRANS_GOAL) != 0) {
		tinfo->goal.period = period;
		tinfo->goal.offset = offset;
		tinfo->goal.ppr_options = ppr_options;
	}

	old_period = tinfo->curr.period;
	old_offset = tinfo->curr.offset;
	old_ppr	   = tinfo->curr.ppr_options;

	if ((type & AHD_TRANS_CUR) != 0
	 && (old_period != period
	  || old_offset != offset
	  || old_ppr != ppr_options)) {

		update_nee