[RFC PATCH 77/71] ncr5380: Fix wait for 53C80 registers registers after PDMA

From: Ondrej Zary
Date: Thu Dec 03 2015 - 18:03:32 EST


The check for 53C80 registers accessibility was commented out because
it was broken (inverted). Fix and enable it.

Signed-off-by: Ondrej Zary <linux@xxxxxxxxxxxxxxxxxxxx>
---
drivers/scsi/g_NCR5380.c | 35 +++++++----------------------------
1 file changed, 7 insertions(+), 28 deletions(-)

diff --git a/drivers/scsi/g_NCR5380.c b/drivers/scsi/g_NCR5380.c
index 04f6c29..c5cd490 100644
--- a/drivers/scsi/g_NCR5380.c
+++ b/drivers/scsi/g_NCR5380.c
@@ -599,14 +599,10 @@ static inline int NCR5380_pread(struct Scsi_Host *instance, unsigned char *dst,
if (!(NCR5380_read(hostdata->c400_ctl_status) & CSR_GATED_53C80_IRQ))
printk("53C400r: no 53C80 gated irq after transfer");

-#if 0
- /*
- * DON'T DO THIS - THEY NEVER ARRIVE!
- */
- printk("53C400r: Waiting for 53C80 registers\n");
- while (NCR5380_read(hostdata->c400_ctl_status) & CSR_53C80_REG)
+ /* wait for 53C80 registers to be available */
+ while (!(NCR5380_read(hostdata->c400_ctl_status) & CSR_53C80_REG))
;
-#endif
+
if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_END_DMA_TRANSFER))
printk(KERN_ERR "53C400r: no end dma signal\n");

@@ -674,36 +670,19 @@ static inline int NCR5380_pwrite(struct Scsi_Host *instance, unsigned char *src,
blocks--;
}

-#if 0
- printk("53C400w: waiting for registers to be available\n");
- THEY NEVER DO ! while (NCR5380_read(hostdata->c400_ctl_status) & CSR_53C80_REG);
- printk("53C400w: Got em\n");
-#endif
-
- /* Let's wait for this instead - could be ugly */
- /* All documentation says to check for this. Maybe my hardware is too
- * fast. Waiting for it seems to work fine! KLL
- */
while (!(i = NCR5380_read(hostdata->c400_ctl_status) & CSR_GATED_53C80_IRQ)) {
udelay(4); /* DTC436 chip hangs without this */
; // FIXME - no timeout
}

- /*
- * I know. i is certainly != 0 here but the loop is new. See previous
- * comment.
- */
- if (i) {
- if (!((i = NCR5380_read(BUS_AND_STATUS_REG)) & BASR_END_DMA_TRANSFER))
- printk(KERN_ERR "53C400w: No END OF DMA bit - WHOOPS! BASR=%0x\n", i);
- } else
- printk(KERN_ERR "53C400w: no 53C80 gated irq after transfer (last block)\n");
+ /* wait for 53C80 registers to be available */
+ while (!(NCR5380_read(hostdata->c400_ctl_status) & CSR_53C80_REG))
+ ;

-#if 0
if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_END_DMA_TRANSFER)) {
printk(KERN_ERR "53C400w: no end dma signal\n");
}
-#endif
+
while (!(NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT))
; // TIMEOUT
return 0;
--
Ondrej Zary

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/