[SCSI] 53c700: Allow setting burst length
This is a patch, which allows not only disabling bursting but to specify
different burst lenghts. This feature is needed to get the 53c700 driver
working for the onboard SCSI controller of SNI RM machines, which only
work reliably with a 4 word burst length.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/53c700.c b/drivers/scsi/53c700.c
index 68103e5..88e061d 100644
--- a/drivers/scsi/53c700.c
+++ b/drivers/scsi/53c700.c
@@ -667,12 +667,30 @@
__u8 min_xferp = (hostdata->chip710 ? NCR_710_MIN_XFERP : NCR_700_MIN_XFERP);
if(hostdata->chip710) {
- __u8 burst_disable = hostdata->burst_disable
- ? BURST_DISABLE : 0;
+ __u8 burst_disable = 0;
+ __u8 burst_length = 0;
+
+ switch (hostdata->burst_length) {
+ case 1:
+ burst_length = BURST_LENGTH_1;
+ break;
+ case 2:
+ burst_length = BURST_LENGTH_2;
+ break;
+ case 4:
+ burst_length = BURST_LENGTH_4;
+ break;
+ case 8:
+ burst_length = BURST_LENGTH_8;
+ break;
+ default:
+ burst_disable = BURST_DISABLE;
+ break;
+ }
dcntl_extra = COMPAT_700_MODE;
NCR_700_writeb(dcntl_extra, host, DCNTL_REG);
- NCR_700_writeb(BURST_LENGTH_8 | hostdata->dmode_extra,
+ NCR_700_writeb(burst_length | hostdata->dmode_extra,
host, DMODE_710_REG);
NCR_700_writeb(burst_disable | (hostdata->differential ?
DIFF : 0), host, CTEST7_REG);
diff --git a/drivers/scsi/53c700.h b/drivers/scsi/53c700.h
index f38822d..841e1bb 100644
--- a/drivers/scsi/53c700.h
+++ b/drivers/scsi/53c700.h
@@ -203,7 +203,7 @@
__u32 force_le_on_be:1;
#endif
__u32 chip710:1; /* set if really a 710 not 700 */
- __u32 burst_disable:1; /* set to 1 to disable 710 bursting */
+ __u32 burst_length:4; /* set to 0 to disable 710 bursting */
/* NOTHING BELOW HERE NEEDS ALTERING */
__u32 fast:1; /* if we can alter the SCSI bus clock
diff --git a/drivers/scsi/lasi700.c b/drivers/scsi/lasi700.c
index f0871c3..2aae1b08 100644
--- a/drivers/scsi/lasi700.c
+++ b/drivers/scsi/lasi700.c
@@ -123,6 +123,7 @@
hostdata->force_le_on_be = 0;
hostdata->chip710 = 1;
hostdata->dmode_extra = DMODE_FC2;
+ hostdata->burst_length = 8;
}
host = NCR_700_detect(&lasi700_template, hostdata, &dev->dev);
diff --git a/drivers/scsi/sim710.c b/drivers/scsi/sim710.c
index 551bacc..018c65f 100644
--- a/drivers/scsi/sim710.c
+++ b/drivers/scsi/sim710.c
@@ -123,6 +123,7 @@
hostdata->differential = differential;
hostdata->clock = clock;
hostdata->chip710 = 1;
+ hostdata->burst_length = 8;
/* and register the chip */
if((host = NCR_700_detect(&sim710_driver_template, hostdata, dev))
