aic7xxx_osm.c

来自「linux 内核源代码」· C语言 代码 · 共 2,346 行 · 第 1/5 页

	hscb = scb->hscb;
	cmd->host_scribble = (char *)scb;

	/*
	 * Fill out basics of the HSCB.
	 */
	hscb->control = 0;
	hscb->scsiid = BUILD_SCSIID(ahc, cmd);
	hscb->lun = cmd->device->lun;
	mask = SCB_GET_TARGET_MASK(ahc, scb);
	tinfo = ahc_fetch_transinfo(ahc, SCB_GET_CHANNEL(ahc, scb),
				    SCB_GET_OUR_ID(scb),
				    SCB_GET_TARGET(ahc, scb), &tstate);
	hscb->scsirate = tinfo->scsirate;
	hscb->scsioffset = tinfo->curr.offset;
	if ((tstate->ultraenb & mask) != 0)
		hscb->control |= ULTRAENB;
	
	if ((ahc->user_discenable & mask) != 0)
		hscb->control |= DISCENB;
	
	if ((tstate->auto_negotiate & mask) != 0) {
		scb->flags |= SCB_AUTO_NEGOTIATE;
		scb->hscb->control |= MK_MESSAGE;
	}

	if ((dev->flags & (AHC_DEV_Q_TAGGED|AHC_DEV_Q_BASIC)) != 0) {
		int	msg_bytes;
		uint8_t tag_msgs[2];
		
		msg_bytes = scsi_populate_tag_msg(cmd, tag_msgs);
		if (msg_bytes && tag_msgs[0] != MSG_SIMPLE_TASK) {
			hscb->control |= tag_msgs[0];
			if (tag_msgs[0] == MSG_ORDERED_TASK)
				dev->commands_since_idle_or_otag = 0;
		} else if (dev->commands_since_idle_or_otag == AHC_OTAG_THRESH
				&& (dev->flags & AHC_DEV_Q_TAGGED) != 0) {
			hscb->control |= MSG_ORDERED_TASK;
			dev->commands_since_idle_or_otag = 0;
		} else {
			hscb->control |= MSG_SIMPLE_TASK;
		}
	}

	hscb->cdb_len = cmd->cmd_len;
	if (hscb->cdb_len <= 12) {
		memcpy(hscb->shared_data.cdb, cmd->cmnd, hscb->cdb_len);
	} else {
		memcpy(hscb->cdb32, cmd->cmnd, hscb->cdb_len);
		scb->flags |= SCB_CDB32_PTR;
	}

	scb->platform_data->xfer_len = 0;
	ahc_set_residual(scb, 0);
	ahc_set_sense_residual(scb, 0);
	scb->sg_count = 0;

	nseg = scsi_dma_map(cmd);
	BUG_ON(nseg < 0);
	if (nseg > 0) {
		struct	ahc_dma_seg *sg;
		struct	scatterlist *cur_seg;
		int i;

		/* Copy the segments into the SG list. */
		sg = scb->sg_list;
		/*
		 * The sg_count may be larger than nseg if
		 * a transfer crosses a 32bit page.
		 */
		scsi_for_each_sg(cmd, cur_seg, nseg, i) {
			dma_addr_t addr;
			bus_size_t len;
			int consumed;

			addr = sg_dma_address(cur_seg);
			len = sg_dma_len(cur_seg);
			consumed = ahc_linux_map_seg(ahc, scb,
						     sg, addr, len);
			sg += consumed;
			scb->sg_count += consumed;
		}
		sg--;
		sg->len |= ahc_htole32(AHC_DMA_LAST_SEG);

		/*
		 * Reset the sg list pointer.
		 */
		scb->hscb->sgptr =
			ahc_htole32(scb->sg_list_phys | SG_FULL_RESID);
		
		/*
		 * Copy the first SG into the "current"
		 * data pointer area.
		 */
		scb->hscb->dataptr = scb->sg_list->addr;
		scb->hscb->datacnt = scb->sg_list->len;
	} else {
		scb->hscb->sgptr = ahc_htole32(SG_LIST_NULL);
		scb->hscb->dataptr = 0;
		scb->hscb->datacnt = 0;
		scb->sg_count = 0;
	}

	LIST_INSERT_HEAD(&ahc->pending_scbs, scb, pending_links);
	dev->openings--;
	dev->active++;
	dev->commands_issued++;
	if ((dev->flags & AHC_DEV_PERIODIC_OTAG) != 0)
		dev->commands_since_idle_or_otag++;
	
	scb->flags |= SCB_ACTIVE;
	if (untagged_q) {
		TAILQ_INSERT_TAIL(untagged_q, scb, links.tqe);
		scb->flags |= SCB_UNTAGGEDQ;
	}
	ahc_queue_scb(ahc, scb);
	return 0;
}

/*
 * SCSI controller interrupt handler.
 */
irqreturn_t
ahc_linux_isr(int irq, void *dev_id)
{
	struct	ahc_softc *ahc;
	u_long	flags;
	int	ours;

	ahc = (struct ahc_softc *) dev_id;
	ahc_lock(ahc, &flags); 
	ours = ahc_intr(ahc);
	ahc_unlock(ahc, &flags);
	return IRQ_RETVAL(ours);
}

void
ahc_platform_flushwork(struct ahc_softc *ahc)
{

}

void
ahc_send_async(struct ahc_softc *ahc, char channel,
	       u_int target, u_int lun, ac_code code)
{
	switch (code) {
	case AC_TRANSFER_NEG:
	{
		char	buf[80];
		struct	scsi_target *starget;
		struct	ahc_linux_target *targ;
		struct	info_str info;
		struct	ahc_initiator_tinfo *tinfo;
		struct	ahc_tmode_tstate *tstate;
		int	target_offset;
		unsigned int target_ppr_options;

		BUG_ON(target == CAM_TARGET_WILDCARD);

		info.buffer = buf;
		info.length = sizeof(buf);
		info.offset = 0;
		info.pos = 0;
		tinfo = ahc_fetch_transinfo(ahc, channel,
						channel == 'A' ? ahc->our_id
							       : ahc->our_id_b,
						target, &tstate);

		/*
		 * Don't bother reporting results while
		 * negotiations are still pending.
		 */
		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)
			if (bootverbose == 0)
				break;

		/*
		 * Don't bother reporting results that
		 * are identical to those last reported.
		 */
		target_offset = target;
		if (channel == 'B')
			target_offset += 8;
		starget = ahc->platform_data->starget[target_offset];
		if (starget == NULL)
			break;
		targ = scsi_transport_target_data(starget);

		target_ppr_options =
			(spi_dt(starget) ? MSG_EXT_PPR_DT_REQ : 0)
			+ (spi_qas(starget) ? MSG_EXT_PPR_QAS_REQ : 0)
			+ (spi_iu(starget) ?  MSG_EXT_PPR_IU_REQ : 0);

		if (tinfo->curr.period == spi_period(starget)
		    && tinfo->curr.width == spi_width(starget)
		    && tinfo->curr.offset == spi_offset(starget)
		 && tinfo->curr.ppr_options == target_ppr_options)
			if (bootverbose == 0)
				break;

		spi_period(starget) = tinfo->curr.period;
		spi_width(starget) = tinfo->curr.width;
		spi_offset(starget) = tinfo->curr.offset;
		spi_dt(starget) = tinfo->curr.ppr_options & MSG_EXT_PPR_DT_REQ ? 1 : 0;
		spi_qas(starget) = tinfo->curr.ppr_options & MSG_EXT_PPR_QAS_REQ ? 1 : 0;
		spi_iu(starget) = tinfo->curr.ppr_options & MSG_EXT_PPR_IU_REQ ? 1 : 0;
		spi_display_xfer_agreement(starget);
		break;
	}
        case AC_SENT_BDR:
	{
		WARN_ON(lun != CAM_LUN_WILDCARD);
		scsi_report_device_reset(ahc->platform_data->host,
					 channel - 'A', target);
		break;
	}
        case AC_BUS_RESET:
		if (ahc->platform_data->host != NULL) {
			scsi_report_bus_reset(ahc->platform_data->host,
					      channel - 'A');
		}
                break;
        default:
                panic("ahc_send_async: Unexpected async event");
        }
}

/*
 * Calls the higher level scsi done function and frees the scb.
 */
void
ahc_done(struct ahc_softc *ahc, struct scb *scb)
{
	struct scsi_cmnd *cmd;
	struct	   ahc_linux_device *dev;

	LIST_REMOVE(scb, pending_links);
	if ((scb->flags & SCB_UNTAGGEDQ) != 0) {
		struct scb_tailq *untagged_q;
		int target_offset;

		target_offset = SCB_GET_TARGET_OFFSET(ahc, scb);
		untagged_q = &(ahc->untagged_queues[target_offset]);
		TAILQ_REMOVE(untagged_q, scb, links.tqe);
		BUG_ON(!TAILQ_EMPTY(untagged_q));
	}

	if ((scb->flags & SCB_ACTIVE) == 0) {
		printf("SCB %d done'd twice\n", scb->hscb->tag);
		ahc_dump_card_state(ahc);
		panic("Stopping for safety");
	}
	cmd = scb->io_ctx;
	dev = scb->platform_data->dev;
	dev->active--;
	dev->openings++;
	if ((cmd->result & (CAM_DEV_QFRZN << 16)) != 0) {
		cmd->result &= ~(CAM_DEV_QFRZN << 16);
		dev->qfrozen--;
	}
	ahc_linux_unmap_scb(ahc, scb);

	/*
	 * Guard against stale sense data.
	 * The Linux mid-layer assumes that sense
	 * was retrieved anytime the first byte of
	 * the sense buffer looks "sane".
	 */
	cmd->sense_buffer[0] = 0;
	if (ahc_get_transaction_status(scb) == CAM_REQ_INPROG) {
		uint32_t amount_xferred;

		amount_xferred =
		    ahc_get_transfer_length(scb) - ahc_get_residual(scb);
		if ((scb->flags & SCB_TRANSMISSION_ERROR) != 0) {
#ifdef AHC_DEBUG
			if ((ahc_debug & AHC_SHOW_MISC) != 0) {
				ahc_print_path(ahc, scb);
				printf("Set CAM_UNCOR_PARITY\n");
			}
#endif
			ahc_set_transaction_status(scb, CAM_UNCOR_PARITY);
#ifdef AHC_REPORT_UNDERFLOWS
		/*
		 * This code is disabled by default as some
		 * clients of the SCSI system do not properly
		 * initialize the underflow parameter.  This
		 * results in spurious termination of commands
		 * that complete as expected (e.g. underflow is
		 * allowed as command can return variable amounts
		 * of data.
		 */
		} else if (amount_xferred < scb->io_ctx->underflow) {
			u_int i;

			ahc_print_path(ahc, scb);
			printf("CDB:");
			for (i = 0; i < scb->io_ctx->cmd_len; i++)
				printf(" 0x%x", scb->io_ctx->cmnd[i]);
			printf("\n");
			ahc_print_path(ahc, scb);
			printf("Saw underflow (%ld of %ld bytes). "
			       "Treated as error\n",
				ahc_get_residual(scb),
				ahc_get_transfer_length(scb));
			ahc_set_transaction_status(scb, CAM_DATA_RUN_ERR);
#endif
		} else {
			ahc_set_transaction_status(scb, CAM_REQ_CMP);
		}
	} else if (ahc_get_transaction_status(scb) == CAM_SCSI_STATUS_ERROR) {
		ahc_linux_handle_scsi_status(ahc, cmd->device, scb);
	}

	if (dev->openings == 1
	 && ahc_get_transaction_status(scb) == CAM_REQ_CMP
	 && ahc_get_scsi_status(scb) != SCSI_STATUS_QUEUE_FULL)
		dev->tag_success_count++;
	/*
	 * Some devices deal with temporary internal resource
	 * shortages by returning queue full.  When the queue
	 * full occurrs, we throttle back.  Slowly try to get
	 * back to our previous queue depth.
	 */
	if ((dev->openings + dev->active) < dev->maxtags
	 && dev->tag_success_count > AHC_TAG_SUCCESS_INTERVAL) {
		dev->tag_success_count = 0;
		dev->openings++;
	}

	if (dev->active == 0)
		dev->commands_since_idle_or_otag = 0;

	if ((scb->flags & SCB_RECOVERY_SCB) != 0) {
		printf("Recovery SCB completes\n");
		if (ahc_get_transaction_status(scb) == CAM_BDR_SENT
		 || ahc_get_transaction_status(scb) == CAM_REQ_ABORTED)
			ahc_set_transaction_status(scb, CAM_CMD_TIMEOUT);

		if (ahc->platform_data->eh_done)
			complete(ahc->platform_data->eh_done);
	}

	ahc_free_scb(ahc, scb);
	ahc_linux_queue_cmd_complete(ahc, cmd);
}

static void
ahc_linux_handle_scsi_status(struct ahc_softc *ahc,
			     struct scsi_device *sdev, struct scb *scb)
{
	struct	ahc_devinfo devinfo;
	struct ahc_linux_device *dev = scsi_transport_device_data(sdev);

	ahc_compile_devinfo(&devinfo,
			    ahc->our_id,
			    sdev->sdev_target->id, sdev->lun,
			    sdev->sdev_target->channel == 0 ? 'A' : 'B',
			    ROLE_INITIATOR);
	
	/*
	 * We don't currently trust the mid-layer to
	 * properly deal with queue full or busy.  So,
	 * when one occurs, we tell the mid-layer to
	 * unconditionally requeue the command to us
	 * so that we can retry it ourselves.  We also
	 * implement our own throttling mechanism so
	 * we don't clobber the device with too many
	 * commands.
	 */
	switch (ahc_get_scsi_status(scb)) {
	default:
		break;
	case SCSI_STATUS_CHECK_COND:
	case SCSI_STATUS_CMD_TERMINATED:
	{
		struct scsi_cmnd *cmd;

		/*
		 * Copy sense information to the OS's cmd
		 * structure if it is available.
		 */
		cmd = scb->io_ctx;
		if (scb->flags & SCB_SENSE) {
			u_int sense_size;

			sense_size = min(sizeof(struct scsi_sense_data)
				       - ahc_get_sense_residual(scb),
					 (u_long)sizeof(cmd->sense_buffer));
			memcpy(cmd->sense_buffer,
			       ahc_get_sense_buf(ahc, scb), sense_size);
			if (sense_size < sizeof(cmd->sense_buffer))
				memset(&cmd->sense_buffer[sense_size], 0,
				       sizeof(cmd->sense_buffer) - sense_size);
			cmd->result |= (DRIVER_SENSE << 24);
#ifdef AHC_DEBUG
			if (ahc_debug & AHC_SHOW_SENSE) {
				int i;

				printf("Copied %d bytes of sense data:",
				       sense_size);
				for (i = 0; i < sense_size; i++) {
					if ((i & 0xF) == 0)
						printf("\n");
					printf("0x%x ", cmd->sense_buffer[i]);
				}
				printf("\n");
			}
#endif
		}
		break;
	}
	case SCSI_STATUS_QUEUE_FULL:
	{
		/*
		 * By the time the core driver has returned this
		 * command, all other commands that were queued
		 * to us but not the device have been returned.
		 * This ensures that dev->active is equal to
		 * the number of commands actually queued to
		 * the device.
		 */
		dev->tag_success_count = 0;
		if (dev->active != 0) {
			/*
			 * Drop our opening count to the number
			 * of commands currently outstanding.
			 */
			dev->openings = 0;
/*
			ahc_print_path(ahc, scb);
			printf("Dropping tag count to %d\n", dev->active);
 */
			if (dev->active == dev->tags_on_last_queuefull) {

				dev->last_queuefull_same_count++;
				/*
				 * If we repeatedly see a queue full
				 * at the same queue depth, this
				 * device has a fixed number of tag
				 * slots.  Lock in this tag depth
				 * so we stop seeing queue fulls from
				 * this device.
				 */
				if (dev->last_queuefull_same_count
				 == AHC_LOCK_TAGS_COUNT) {
					dev->maxtags = dev->active;
					ahc_print_path(ahc, scb);
					printf("Locking max tag count at %d\n",
					       dev->active);
				}
			} else {
				dev->tags_on_last_queuefull = dev->active;
				dev->last_queuefull_same_count = 0;
			}
			ahc_set_transaction_status(scb, CAM_REQUEUE_REQ);
			ahc_set_scsi_status(scb, SCSI_STATUS_OK);
			ahc_platform_set_tags(ahc, sdev, &devinfo,
				     (dev->flags & AHC_DEV_Q_BASIC)
				   ? AHC_QUEUE_BASIC : AHC_QUEUE_TAGGED);
			break;
		}
		/*
		 * Drop down to a single opening, and treat this
		 * as if the target returned BUSY SCSI status.