[SCSI] update spi transport class so that u320 Domain Validation works

There are several extra things that have to be considered when running
Domain Validation on a u320 target (notably how you fall back).

Hopefully this should help us when someone adds this transport class to
aic79xx.

I've tested this on the lsi1030, so I know it works correctly up to
u320.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

diff --git a/drivers/scsi/scsi_transport_spi.c b/drivers/scsi/scsi_transport_spi.c
index 67c6cc4..c87ae46 100644 (file)
--- a/drivers/scsi/scsi_transport_spi.c
+++ b/drivers/scsi/scsi_transport_spi.c
@@ -669,6 +669,7 @@ spi_dv_retrain(struct scsi_request *sreq, u8 *buffer, u8 *ptr,
 {
        struct spi_internal *i = to_spi_internal(sreq->sr_host->transportt);
        struct scsi_device *sdev = sreq->sr_device;
+       struct scsi_target *starget = sdev->sdev_target;
        int period = 0, prevperiod = 0; 
        enum spi_compare_returns retval;
 
@@ -682,24 +683,40 @@ spi_dv_retrain(struct scsi_request *sreq, u8 *buffer, u8 *ptr,
                        break;
 
                /* OK, retrain, fallback */
+               if (i->f->get_iu)
+                       i->f->get_iu(starget);
+               if (i->f->get_qas)
+                       i->f->get_qas(starget);
                if (i->f->get_period)
                        i->f->get_period(sdev->sdev_target);
-               newperiod = spi_period(sdev->sdev_target);
-               period = newperiod > period ? newperiod : period;
-               if (period < 0x0d)
-                       period++;
-               else
-                       period += period >> 1;
-
-               if (unlikely(period > 0xff || period == prevperiod)) {
-                       /* Total failure; set to async and return */
-                       SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Domain Validation Failure, dropping back to Asynchronous\n");
-                       DV_SET(offset, 0);
-                       return SPI_COMPARE_FAILURE;
+
+               /* Here's the fallback sequence; first try turning off
+                * IU, then QAS (if we can control them), then finally
+                * fall down the periods */
+               if (i->f->set_iu && spi_iu(starget)) {
+                       SPI_PRINTK(starget, KERN_ERR, "Domain Validation Disabing Information Units\n");
+                       DV_SET(iu, 0);
+               } else if (i->f->set_qas && spi_qas(starget)) {
+                       SPI_PRINTK(starget, KERN_ERR, "Domain Validation Disabing Quick Arbitration and Selection\n");
+                       DV_SET(qas, 0);
+               } else {
+                       newperiod = spi_period(starget);
+                       period = newperiod > period ? newperiod : period;
+                       if (period < 0x0d)
+                               period++;
+                       else
+                               period += period >> 1;
+
+                       if (unlikely(period > 0xff || period == prevperiod)) {
+                               /* Total failure; set to async and return */
+                               SPI_PRINTK(starget, KERN_ERR, "Domain Validation Failure, dropping back to Asynchronous\n");
+                               DV_SET(offset, 0);
+                               return SPI_COMPARE_FAILURE;
+                       }
+                       SPI_PRINTK(starget, KERN_ERR, "Domain Validation detected failure, dropping back\n");
+                       DV_SET(period, period);
+                       prevperiod = period;
                }
-               SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Domain Validation detected failure, dropping back\n");
-               DV_SET(period, period);
-               prevperiod = period;
        }
        return retval;
 }
@@ -768,23 +785,21 @@ spi_dv_device_internal(struct scsi_request *sreq, u8 *buffer)
        
        if (spi_dv_device_compare_inquiry(sreq, buffer, buffer, DV_LOOPS)
            != SPI_COMPARE_SUCCESS) {
-               SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Domain Validation Initial Inquiry Failed\n");
+               SPI_PRINTK(starget, KERN_ERR, "Domain Validation Initial Inquiry Failed\n");
                /* FIXME: should probably offline the device here? */
                return;
        }
 
        /* test width */
        if (i->f->set_width && spi_max_width(starget) && sdev->wdtr) {
-               i->f->set_width(sdev->sdev_target, 1);
-
-               printk("WIDTH IS %d\n", spi_max_width(starget));
+               i->f->set_width(starget, 1);
 
                if (spi_dv_device_compare_inquiry(sreq, buffer,
                                                   buffer + len,
                                                   DV_LOOPS)
                    != SPI_COMPARE_SUCCESS) {
-                       SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Wide Transfers Fail\n");
-                       i->f->set_width(sdev->sdev_target, 0);
+                       SPI_PRINTK(starget, KERN_ERR, "Wide Transfers Fail\n");
+                       i->f->set_width(starget, 0);
                }
        }
 
@@ -792,7 +807,7 @@ spi_dv_device_internal(struct scsi_request *sreq, u8 *buffer)
                return;
 
        /* device can't handle synchronous */
-       if(!sdev->ppr && !sdev->sdtr)
+       if (!sdev->ppr && !sdev->sdtr)
                return;
 
        /* see if the device has an echo buffer.  If it does we can
@@ -807,16 +822,30 @@ spi_dv_device_internal(struct scsi_request *sreq, u8 *buffer)
        /* now set up to the maximum */
        DV_SET(offset, spi_max_offset(starget));
        DV_SET(period, spi_min_period(starget));
+       /* try QAS requests; this should be harmless to set if the
+        * target supports it */
+       DV_SET(qas, 1);
+       /* Also try IU transfers */
+       DV_SET(iu, 1);
+       if (spi_min_period(starget) < 9) {
+               /* This u320 (or u640). Ignore the coupled parameters
+                * like DT and IU, but set the optional ones */
+               DV_SET(rd_strm, 1);
+               DV_SET(wr_flow, 1);
+               DV_SET(rti, 1);
+               if (spi_min_period(starget) == 8)
+                       DV_SET(pcomp_en, 1);
+       }
 
        if (len == 0) {
-               SPI_PRINTK(sdev->sdev_target, KERN_INFO, "Domain Validation skipping write tests\n");
+               SPI_PRINTK(starget, KERN_INFO, "Domain Validation skipping write tests\n");
                spi_dv_retrain(sreq, buffer, buffer + len,
                               spi_dv_device_compare_inquiry);
                return;
        }
 
        if (len > SPI_MAX_ECHO_BUFFER_SIZE) {
-               SPI_PRINTK(sdev->sdev_target, KERN_WARNING, "Echo buffer size %d is too big, trimming to %d\n", len, SPI_MAX_ECHO_BUFFER_SIZE);
+               SPI_PRINTK(starget, KERN_WARNING, "Echo buffer size %d is too big, trimming to %d\n", len, SPI_MAX_ECHO_BUFFER_SIZE);
                len = SPI_MAX_ECHO_BUFFER_SIZE;
        }