[SCSI] hpsa: rename scsi prefetch field

The field contains more bits than just the one
to indicate whether scsi prefetch should be turned on.

Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index f929875..25afeb4 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -4382,15 +4382,15 @@
 	return true;
 }
 
-/* Need to enable prefetch in the SCSI core for 6400 in x86 */
-static inline void hpsa_enable_scsi_prefetch(struct ctlr_info *h)
+static inline void hpsa_set_driver_support_bits(struct ctlr_info *h)
 {
 #ifdef CONFIG_X86
-	u32 prefetch;
+	/* Need to enable prefetch in the SCSI core for 6400 in x86 */
+	u32 driver_support;
 
-	prefetch = readl(&(h->cfgtable->SCSI_Prefetch));
-	prefetch |= 0x100;
-	writel(prefetch, &(h->cfgtable->SCSI_Prefetch));
+	driver_support = readl(&(h->cfgtable->driver_support));
+	driver_support |= ENABLE_SCSI_PREFETCH;
+	writel(driver_support, &(h->cfgtable->driver_support));
 #endif
 }
 
@@ -4501,7 +4501,7 @@
 		err = -ENODEV;
 		goto err_out_free_res;
 	}
-	hpsa_enable_scsi_prefetch(h);
+	hpsa_set_driver_support_bits(h);
 	hpsa_p600_dma_prefetch_quirk(h);
 	err = hpsa_enter_simple_mode(h);
 	if (err)