ncr5380: Remove UNSAFE macro
authorFinn Thain <fthain@telegraphics.com.au>
Sun, 3 Jan 2016 05:05:39 +0000 (16:05 +1100)
committerMartin K. Petersen <martin.petersen@oracle.com>
Thu, 7 Jan 2016 02:43:00 +0000 (21:43 -0500)
Configuring core drivers using macros like this one prevents re-unifying
the core driver forks, and prevents implementing the core driver as a
library or a platform driver.

The UNSAFE macro in particular is a poor workaround for the problem of
interrupt latency. Releasing the locks complicates things because then we
would have to handle the possibility of EH handler invocation during a
PDMA transfer.

The comments say that instead of using this macro, "you're going to be
better off twiddling with transfersize". I agree. Remove this stuff.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
drivers/scsi/NCR5380.c
drivers/scsi/dtc.c
drivers/scsi/pas16.c

index 8ff59509585cde89a3edf00b1462d2aaa4639e98..1a6562b94bf75e8fb68452341659bb6d21f3988c 100644 (file)
  *      rely on phase mismatch and EOP interrupts to determine end 
  *      of phase.
  *
- * UNSAFE - leave interrupts enabled during pseudo-DMA transfers.  You
- *          only really want to use this if you're having a problem with
- *          dropped characters during high speed communications, and even
- *          then, you're going to be better off twiddling with transfersize
- *          in the high level code.
- *
  * Defaults for these will be provided although the user may want to adjust 
  * these to allocate CPU resources to the SCSI driver or "real" code.
  * 
@@ -553,9 +547,6 @@ static void prepare_info(struct Scsi_Host *instance)
 #endif
 #ifdef PSEUDO_DMA
                 "PSEUDO_DMA "
-#endif
-#ifdef UNSAFE
-                "UNSAFE "
 #endif
                 "");
 }
@@ -1582,9 +1573,6 @@ static int NCR5380_transfer_dma(struct Scsi_Host *instance, unsigned char *phase
         * before the setting of DMA mode to after transfer of the last byte.
         */
 
-#if defined(PSEUDO_DMA) && defined(UNSAFE)
-       spin_unlock_irq(instance->host_lock);
-#endif
        /* KLL May need eop and parity in 53c400 */
        if (hostdata->flags & FLAG_NCR53C400)
                NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE |
@@ -1793,9 +1781,6 @@ static int NCR5380_transfer_dma(struct Scsi_Host *instance, unsigned char *phase
        *data = d + c;
        *count = 0;
        *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
-#if defined(PSEUDO_DMA) && defined(UNSAFE)
-       spin_lock_irq(instance->host_lock);
-#endif                         /* defined(REAL_DMA_POLL) */
        return foo;
 #endif                         /* def REAL_DMA */
 }
index 010d9b13aae7d20a369ba1158b0d9b09915fccfc..60bffb34ecfba44febfd6fdb047b8d140f95c12b 100644 (file)
@@ -1,7 +1,5 @@
-
 #define PSEUDO_DMA
 #define DONT_USE_INTR
-#define UNSAFE                 /* Leave interrupts enabled during pseudo-dma I/O */
 #define DMA_WORKS_RIGHT
 
 
index 5e57ee01093c12b8ec47f57cd6f47c06c8d65115..4570536187d8a7ec7ab82f104d4da50e3b4a2c29 100644 (file)
@@ -1,5 +1,4 @@
 #define PSEUDO_DMA
-#define UNSAFE  /* Not unsafe for PAS16 -- use it */
 
 /*
  * This driver adapted from Drew Eckhardt's Trantor T128 driver