[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>

1 files changed, 53 insertions, 24 deletions

diff --git a/drivers/scsi/scsi_transport_spi.c b/drivers/scsi/scsi_transport_spi.c
index 67c6cc40ce16..c87ae469d707 100644
--- 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;
         }