[PATCH v4 03/23] ncr5380: Remove REAL_DMA and REAL_DMA_POLL macros

From: Finn Thain
Date: Wed Mar 23 2016 - 06:21:14 EST

For the NCR5380.c core driver, these macros are never used.
If REAL_DMA were to be defined, compilation would fail.

For the atari_NCR5380.c core driver, REAL_DMA is always defined.

Hence these macros are pointless.

Signed-off-by: Finn Thain <fthain@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Hannes Reinecke <hare@xxxxxxxx>
Tested-by: Michael Schmitz <schmitzmic@xxxxxxxxx>
Tested-by: Ondrej Zary <linux@xxxxxxxxxxxxxxxxxxxx>

---
drivers/scsi/NCR5380.c | 218 +------------------------------------------
drivers/scsi/NCR5380.h | 112 ----------------------
drivers/scsi/atari_NCR5380.c | 62 +-----------
drivers/scsi/atari_scsi.c | 32 ------
drivers/scsi/sun3_scsi.c | 13 --
5 files changed, 22 insertions(+), 415 deletions(-)

Index: linux/drivers/scsi/NCR5380.c
===================================================================
--- linux.orig/drivers/scsi/NCR5380.c 2016-03-23 21:09:20.000000000 +1100
+++ linux/drivers/scsi/NCR5380.c 2016-03-23 21:09:22.000000000 +1100
@@ -35,18 +35,10 @@
* code so that everything does the same thing that's done at the
* end of a pseudo-DMA read operation.
*
- * 2. Fix REAL_DMA (interrupt driven, polled works fine) -
- * basically, transfer size needs to be reduced by one
- * and the last byte read as is done with PSEUDO_DMA.
- *
* 4. Test SCSI-II tagged queueing (I have no devices which support
* tagged queueing)
*/

-#ifndef notyet
-#undef REAL_DMA
-#endif
-
#ifdef BOARD_REQUIRES_NO_DELAY
#define io_recovery_delay(x)
#else
@@ -131,12 +123,6 @@
*
* PSEUDO_DMA - if defined, PSEUDO DMA is used during the data transfer phases.
*
- * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
- *
- * REAL_DMA_POLL - if defined, REAL DMA is used but the driver doesn't
- * rely on phase mismatch and EOP interrupts to determine end
- * of phase.
- *
* These macros MUST be defined :
*
* NCR5380_read(register) - read from the specified register
@@ -147,15 +133,9 @@
* specific implementation of the NCR5380
*
* Either real DMA *or* pseudo DMA may be implemented
- * REAL functions :
- * NCR5380_REAL_DMA should be defined if real DMA is to be used.
* Note that the DMA setup functions should return the number of bytes
* that they were able to program the controller for.
*
- * Also note that generic i386/PC versions of these macros are
- * available as NCR5380_i386_dma_write_setup,
- * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
- *
* NCR5380_dma_write_setup(instance, src, count) - initialize
* NCR5380_dma_read_setup(instance, dst, count) - initialize
* NCR5380_dma_residual(instance); - residual count
@@ -486,12 +466,6 @@ static void prepare_info(struct Scsi_Hos
#ifdef DIFFERENTIAL
"DIFFERENTIAL "
#endif
-#ifdef REAL_DMA
- "REAL_DMA "
-#endif
-#ifdef REAL_DMA_POLL
- "REAL_DMA_POLL "
-#endif
#ifdef PARITY
"PARITY "
#endif
@@ -551,9 +525,8 @@ static int NCR5380_init(struct Scsi_Host
hostdata->id_higher_mask |= i;
for (i = 0; i < 8; ++i)
hostdata->busy[i] = 0;
-#ifdef REAL_DMA
- hostdata->dmalen = 0;
-#endif
+ hostdata->dma_len = 0;
+
spin_lock_init(&hostdata->lock);
hostdata->connected = NULL;
hostdata->sensing = NULL;
@@ -850,11 +823,7 @@ static void NCR5380_main(struct work_str
requeue_cmd(instance, cmd);
}
}
- if (hostdata->connected
-#ifdef REAL_DMA
- && !hostdata->dmalen
-#endif
- ) {
+ if (hostdata->connected && !hostdata->dma_len) {
dsprintk(NDEBUG_MAIN, instance, "main: performing information transfer\n");
NCR5380_information_transfer(instance);
done = 0;
@@ -919,34 +888,6 @@ static irqreturn_t NCR5380_intr(int irq,
dsprintk(NDEBUG_INTR, instance, "IRQ %d, BASR 0x%02x, SR 0x%02x, MR 0x%02x\n",
irq, basr, sr, mr);

-#if defined(REAL_DMA)
- if ((mr & MR_DMA_MODE) || (mr & MR_MONITOR_BSY)) {
- /* Probably End of DMA, Phase Mismatch or Loss of BSY.
- * We ack IRQ after clearing Mode Register. Workarounds
- * for End of DMA errata need to happen in DMA Mode.
- */
-
- dsprintk(NDEBUG_INTR, instance, "interrupt in DMA mode\n");
-
- int transferred;
-
- if (!hostdata->connected)
- panic("scsi%d : DMA interrupt with no connected cmd\n",
- instance->hostno);
-
- transferred = hostdata->dmalen - NCR5380_dma_residual(instance);
- hostdata->connected->SCp.this_residual -= transferred;
- hostdata->connected->SCp.ptr += transferred;
- hostdata->dmalen = 0;
-
- /* FIXME: we need to poll briefly then defer a workqueue task ! */
- NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG, BASR_ACK, 0, 2 * HZ);
-
- NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
- NCR5380_write(MODE_REG, MR_BASE);
- NCR5380_read(RESET_PARITY_INTERRUPT_REG);
- } else
-#endif /* REAL_DMA */
if ((NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_mask) &&
(sr & (SR_SEL | SR_IO | SR_BSY | SR_RST)) == (SR_SEL | SR_IO)) {
/* Probably reselected */
@@ -1495,7 +1436,7 @@ timeout:
return -1;
}

-#if defined(REAL_DMA) || defined(PSEUDO_DMA) || defined (REAL_DMA_POLL)
+#if defined(PSEUDO_DMA)
/*
* Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
* unsigned char *phase, int *count, unsigned char **data)
@@ -1525,34 +1466,14 @@ static int NCR5380_transfer_dma(struct S
register unsigned char *d = *data;
unsigned char tmp;
int foo;
-#if defined(REAL_DMA_POLL)
- int cnt, toPIO;
- unsigned char saved_data = 0, overrun = 0, residue;
-#endif

if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
*phase = tmp;
return -1;
}
-#if defined(REAL_DMA) || defined(REAL_DMA_POLL)
- if (p & SR_IO) {
- if (!(hostdata->flags & FLAG_NO_DMA_FIXUPS))
- c -= 2;
- }
- hostdata->dma_len = (p & SR_IO) ? NCR5380_dma_read_setup(instance, d, c) : NCR5380_dma_write_setup(instance, d, c);
-
- dsprintk(NDEBUG_DMA, instance, "initializing DMA %s: length %d, address %p\n",
- (p & SR_IO) ? "receive" : "send", c, *data);
-#endif

NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));

-#ifdef REAL_DMA
- NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_MONITOR_BSY |
- MR_ENABLE_EOP_INTR);
-#elif defined(REAL_DMA_POLL)
- NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_MONITOR_BSY);
-#else
/*
* Note : on my sample board, watch-dog timeouts occurred when interrupts
* were not disabled for the duration of a single DMA transfer, from
@@ -1564,7 +1485,6 @@ static int NCR5380_transfer_dma(struct S
MR_ENABLE_EOP_INTR);
else
NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_MONITOR_BSY);
-#endif /* def REAL_DMA */

dprintk(NDEBUG_DMA, "scsi%d : mode reg = 0x%X\n", instance->host_no, NCR5380_read(MODE_REG));

@@ -1584,14 +1504,8 @@ static int NCR5380_transfer_dma(struct S
io_recovery_delay(1);
}

-#if defined(REAL_DMA_POLL)
- do {
- tmp = NCR5380_read(BUS_AND_STATUS_REG);
- } while ((tmp & BASR_PHASE_MATCH) && !(tmp & (BASR_BUSY_ERROR | BASR_END_DMA_TRANSFER)));
-
/*
- * At this point, either we've completed DMA, or we have a phase mismatch,
- * or we've unexpectedly lost BUSY (which is a real error).
+ * A note regarding the DMA errata workarounds for early NMOS silicon.
*
* For DMA sends, we want to wait until the last byte has been
* transferred out over the bus before we turn off DMA mode. Alas, there
@@ -1618,79 +1532,18 @@ static int NCR5380_transfer_dma(struct S
* properly, or the target switches to MESSAGE IN phase to signal a
* disconnection (either operation bringing the DMA to a clean halt).
* However, in order to handle scatter-receive, we must work around the
- * problem. The chosen fix is to DMA N-2 bytes, then check for the
+ * problem. The chosen fix is to DMA fewer bytes, then check for the
* condition before taking the NCR5380 out of DMA mode. One or two extra
* bytes are transferred via PIO as necessary to fill out the original
* request.
*/

if (p & SR_IO) {
- if (!(hostdata->flags & FLAG_NO_DMA_FIXUPS)) {
- udelay(10);
- if ((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) ==
- (BASR_PHASE_MATCH | BASR_ACK)) {
- saved_data = NCR5380_read(INPUT_DATA_REGISTER);
- overrun = 1;
- }
- }
- } else {
- int limit = 100;
- while (((tmp = NCR5380_read(BUS_AND_STATUS_REG)) & BASR_ACK) || (NCR5380_read(STATUS_REG) & SR_REQ)) {
- if (!(tmp & BASR_PHASE_MATCH))
- break;
- if (--limit < 0)
- break;
- }
- }
-
- dsprintk(NDEBUG_DMA, "polled DMA transfer complete, basr 0x%02x, sr 0x%02x\n",
- tmp, NCR5380_read(STATUS_REG));
-
- NCR5380_write(MODE_REG, MR_BASE);
- NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
-
- residue = NCR5380_dma_residual(instance);
- c -= residue;
- *count -= c;
- *data += c;
- *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
-
- if (!(hostdata->flags & FLAG_NO_DMA_FIXUPS) &&
- *phase == p && (p & SR_IO) && residue == 0) {
- if (overrun) {
- dprintk(NDEBUG_DMA, "Got an input overrun, using saved byte\n");
- **data = saved_data;
- *data += 1;
- *count -= 1;
- cnt = toPIO = 1;
- } else {
- printk("No overrun??\n");
- cnt = toPIO = 2;
- }
- dprintk(NDEBUG_DMA, "Doing %d-byte PIO to 0x%X\n", cnt, *data);
- NCR5380_transfer_pio(instance, phase, &cnt, data);
- *count -= toPIO - cnt;
- }
-
- dprintk(NDEBUG_DMA, "Return with data ptr = 0x%X, count %d, last 0x%X, next 0x%X\n", *data, *count, *(*data + *count - 1), *(*data + *count));
- return 0;
-
-#elif defined(REAL_DMA)
- return 0;
-#else /* defined(REAL_DMA_POLL) */
- if (p & SR_IO) {
foo = NCR5380_pread(instance, d,
hostdata->flags & FLAG_NO_DMA_FIXUP ? c : c - 1);
if (!foo && !(hostdata->flags & FLAG_NO_DMA_FIXUP)) {
/*
- * We can't disable DMA mode after successfully transferring
- * what we plan to be the last byte, since that would open up
- * a race condition where if the target asserted REQ before
- * we got the DMA mode reset, the NCR5380 would have latched
- * an additional byte into the INPUT DATA register and we'd
- * have dropped it.
- *
- * The workaround was to transfer one fewer bytes than we
+ * The workaround was to transfer fewer bytes than we
* intended to with the pseudo-DMA read function, wait for
* the chip to latch the last byte, read it, and then disable
* pseudo-DMA mode.
@@ -1738,9 +1591,8 @@ static int NCR5380_transfer_dma(struct S
*count = 0;
*phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
return foo;
-#endif /* def REAL_DMA */
}
-#endif /* defined(REAL_DMA) | defined(PSEUDO_DMA) */
+#endif /* PSEUDO_DMA */

/*
* Function : NCR5380_information_transfer (struct Scsi_Host *instance)
@@ -1831,7 +1683,7 @@ static void NCR5380_information_transfer
* in an unconditional loop.
*/

-#if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
+#if defined(PSEUDO_DMA)
transfersize = 0;
if (!cmd->device->borken)
transfersize = NCR5380_dma_xfer_len(instance, cmd, phase);
@@ -1855,7 +1707,7 @@ static void NCR5380_information_transfer
} else
cmd->SCp.this_residual -= transfersize - len;
} else
-#endif /* defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) */
+#endif /* PSEUDO_DMA */
{
/* Break up transfer into 3 ms chunks,
* presuming 6 accesses per handshake.
@@ -2202,52 +2054,6 @@ static void NCR5380_reselect(struct Scsi
scmd_id(tmp), tmp->device->lun, tmp->tag);
}

-/*
- * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
- *
- * Purpose : called by interrupt handler when DMA finishes or a phase
- * mismatch occurs (which would finish the DMA transfer).
- *
- * Inputs : instance - this instance of the NCR5380.
- *
- * Returns : pointer to the scsi_cmnd structure for which the I_T_L
- * nexus has been reestablished, on failure NULL is returned.
- */
-
-#ifdef REAL_DMA
-static void NCR5380_dma_complete(NCR5380_instance * instance) {
- struct NCR5380_hostdata *hostdata = shost_priv(instance);
- int transferred;
-
- /*
- * XXX this might not be right.
- *
- * Wait for final byte to transfer, ie wait for ACK to go false.
- *
- * We should use the Last Byte Sent bit, unfortunately this is
- * not available on the 5380/5381 (only the various CMOS chips)
- *
- * FIXME: timeout, and need to handle long timeout/irq case
- */
-
- NCR5380_poll_politely(instance, BUS_AND_STATUS_REG, BASR_ACK, 0, 5*HZ);
-
- NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
-
- /*
- * The only places we should see a phase mismatch and have to send
- * data from the same set of pointers will be the data transfer
- * phases. So, residual, requested length are only important here.
- */
-
- if (!(hostdata->connected->SCp.phase & SR_CD)) {
- transferred = instance->dmalen - NCR5380_dma_residual();
- hostdata->connected->SCp.this_residual -= transferred;
- hostdata->connected->SCp.ptr += transferred;
- }
-}
-#endif /* def REAL_DMA */
-
/**
* list_find_cmd - test for presence of a command in a linked list
* @haystack: list of commands
@@ -2359,9 +2165,7 @@ static int NCR5380_abort(struct scsi_cmn
if (hostdata->connected == cmd) {
dsprintk(NDEBUG_ABORT, instance, "abort: cmd %p is connected\n", cmd);
hostdata->connected = NULL;
-#ifdef REAL_DMA
hostdata->dma_len = 0;
-#endif
if (do_abort(instance)) {
set_host_byte(cmd, DID_ERROR);
complete_cmd(instance, cmd);
@@ -2464,9 +2268,7 @@ static int NCR5380_bus_reset(struct scsi

for (i = 0; i < 8; ++i)
hostdata->busy[i] = 0;
-#ifdef REAL_DMA
hostdata->dma_len = 0;
-#endif

queue_work(hostdata->work_q, &hostdata->main_task);
spin_unlock_irqrestore(&hostdata->lock, flags);
Index: linux/drivers/scsi/NCR5380.h
===================================================================
--- linux.orig/drivers/scsi/NCR5380.h 2016-03-23 21:05:16.000000000 +1100
+++ linux/drivers/scsi/NCR5380.h 2016-03-23 21:09:22.000000000 +1100
@@ -239,9 +239,7 @@ struct NCR5380_hostdata {
struct Scsi_Host *host; /* Host backpointer */
unsigned char id_mask, id_higher_mask; /* 1 << id, all bits greater */
unsigned char busy[8]; /* index = target, bit = lun */
-#if defined(REAL_DMA) || defined(REAL_DMA_POLL)
int dma_len; /* requested length of DMA */
-#endif
unsigned char last_message; /* last message OUT */
struct scsi_cmnd *connected; /* currently connected cmnd */
struct scsi_cmnd *selecting; /* cmnd to be connected */
@@ -319,118 +317,8 @@ static void NCR5380_main(struct work_str
static const char *NCR5380_info(struct Scsi_Host *instance);
static void NCR5380_reselect(struct Scsi_Host *instance);
static struct scsi_cmnd *NCR5380_select(struct Scsi_Host *, struct scsi_cmnd *);
-#if defined(PSEUDO_DMA) || defined(REAL_DMA) || defined(REAL_DMA_POLL)
static int NCR5380_transfer_dma(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data);
-#endif
static int NCR5380_transfer_pio(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data);

-#if (defined(REAL_DMA) || defined(REAL_DMA_POLL))
-
-#if defined(i386) || defined(__alpha__)
-
-/**
- * NCR5380_pc_dma_setup - setup ISA DMA
- * @instance: adapter to set up
- * @ptr: block to transfer (virtual address)
- * @count: number of bytes to transfer
- * @mode: DMA controller mode to use
- *
- * Program the DMA controller ready to perform an ISA DMA transfer
- * on this chip.
- *
- * Locks: takes and releases the ISA DMA lock.
- */
-
-static __inline__ int NCR5380_pc_dma_setup(struct Scsi_Host *instance, unsigned char *ptr, unsigned int count, unsigned char mode)
-{
- unsigned limit;
- unsigned long bus_addr = virt_to_bus(ptr);
- unsigned long flags;
-
- if (instance->dma_channel <= 3) {
- if (count > 65536)
- count = 65536;
- limit = 65536 - (bus_addr & 0xFFFF);
- } else {
- if (count > 65536 * 2)
- count = 65536 * 2;
- limit = 65536 * 2 - (bus_addr & 0x1FFFF);
- }
-
- if (count > limit)
- count = limit;
-
- if ((count & 1) || (bus_addr & 1))
- panic("scsi%d : attempted unaligned DMA transfer\n", instance->host_no);
-
- flags=claim_dma_lock();
- disable_dma(instance->dma_channel);
- clear_dma_ff(instance->dma_channel);
- set_dma_addr(instance->dma_channel, bus_addr);
- set_dma_count(instance->dma_channel, count);
- set_dma_mode(instance->dma_channel, mode);
- enable_dma(instance->dma_channel);
- release_dma_lock(flags);
-
- return count;
-}
-
-/**
- * NCR5380_pc_dma_write_setup - setup ISA DMA write
- * @instance: adapter to set up
- * @ptr: block to transfer (virtual address)
- * @count: number of bytes to transfer
- *
- * Program the DMA controller ready to perform an ISA DMA write to the
- * SCSI controller.
- *
- * Locks: called routines take and release the ISA DMA lock.
- */
-
-static __inline__ int NCR5380_pc_dma_write_setup(struct Scsi_Host *instance, unsigned char *src, unsigned int count)
-{
- return NCR5380_pc_dma_setup(instance, src, count, DMA_MODE_WRITE);
-}
-
-/**
- * NCR5380_pc_dma_read_setup - setup ISA DMA read
- * @instance: adapter to set up
- * @ptr: block to transfer (virtual address)
- * @count: number of bytes to transfer
- *
- * Program the DMA controller ready to perform an ISA DMA read from the
- * SCSI controller.
- *
- * Locks: called routines take and release the ISA DMA lock.
- */
-
-static __inline__ int NCR5380_pc_dma_read_setup(struct Scsi_Host *instance, unsigned char *src, unsigned int count)
-{
- return NCR5380_pc_dma_setup(instance, src, count, DMA_MODE_READ);
-}
-
-/**
- * NCR5380_pc_dma_residual - return bytes left
- * @instance: adapter
- *
- * Reports the number of bytes left over after the DMA was terminated.
- *
- * Locks: takes and releases the ISA DMA lock.
- */
-
-static __inline__ int NCR5380_pc_dma_residual(struct Scsi_Host *instance)
-{
- unsigned long flags;
- int tmp;
-
- flags = claim_dma_lock();
- clear_dma_ff(instance->dma_channel);
- tmp = get_dma_residue(instance->dma_channel);
- release_dma_lock(flags);
-
- return tmp;
-}
-#endif /* defined(i386) || defined(__alpha__) */
-#endif /* defined(REAL_DMA) */
#endif /* __KERNEL__ */
#endif /* NCR5380_H */
Index: linux/drivers/scsi/atari_NCR5380.c
===================================================================
--- linux.orig/drivers/scsi/atari_NCR5380.c 2016-03-23 21:09:19.000000000 +1100
+++ linux/drivers/scsi/atari_NCR5380.c 2016-03-23 21:09:22.000000000 +1100
@@ -112,15 +112,9 @@
* specific implementation of the NCR5380
*
* Either real DMA *or* pseudo DMA may be implemented
- * REAL functions :
- * NCR5380_REAL_DMA should be defined if real DMA is to be used.
* Note that the DMA setup functions should return the number of bytes
* that they were able to program the controller for.
*
- * Also note that generic i386/PC versions of these macros are
- * available as NCR5380_i386_dma_write_setup,
- * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
- *
* NCR5380_dma_write_setup(instance, src, count) - initialize
* NCR5380_dma_read_setup(instance, dst, count) - initialize
* NCR5380_dma_residual(instance); - residual count
@@ -586,9 +580,6 @@ static void prepare_info(struct Scsi_Hos
#ifdef DIFFERENTIAL
"DIFFERENTIAL "
#endif
-#ifdef REAL_DMA
- "REAL_DMA "
-#endif
#ifdef PARITY
"PARITY "
#endif
@@ -629,9 +620,8 @@ static int __init NCR5380_init(struct Sc
#ifdef SUPPORT_TAGS
init_tags(hostdata);
#endif
-#if defined (REAL_DMA)
hostdata->dma_len = 0;
-#endif
+
spin_lock_init(&hostdata->lock);
hostdata->connected = NULL;
hostdata->sensing = NULL;
@@ -974,11 +964,7 @@ static void NCR5380_main(struct work_str
#endif
}
}
- if (hostdata->connected
-#ifdef REAL_DMA
- && !hostdata->dma_len
-#endif
- ) {
+ if (hostdata->connected && !hostdata->dma_len) {
dsprintk(NDEBUG_MAIN, instance, "main: performing information transfer\n");
NCR5380_information_transfer(instance);
done = 0;
@@ -990,7 +976,6 @@ static void NCR5380_main(struct work_str
}


-#ifdef REAL_DMA
/*
* Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
*
@@ -1071,7 +1056,6 @@ static void NCR5380_dma_complete(struct
}
}
}
-#endif /* REAL_DMA */


/**
@@ -1126,7 +1110,6 @@ static irqreturn_t NCR5380_intr(int irq,
dsprintk(NDEBUG_INTR, instance, "IRQ %d, BASR 0x%02x, SR 0x%02x, MR 0x%02x\n",
irq, basr, sr, mr);

-#if defined(REAL_DMA)
if ((mr & MR_DMA_MODE) || (mr & MR_MONITOR_BSY)) {
/* Probably End of DMA, Phase Mismatch or Loss of BSY.
* We ack IRQ after clearing Mode Register. Workarounds
@@ -1142,9 +1125,7 @@ static irqreturn_t NCR5380_intr(int irq,
NCR5380_write(MODE_REG, MR_BASE);
NCR5380_read(RESET_PARITY_INTERRUPT_REG);
}
- } else
-#endif /* REAL_DMA */
- if ((NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_mask) &&
+ } else if ((NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_mask) &&
(sr & (SR_SEL | SR_IO | SR_BSY | SR_RST)) == (SR_SEL | SR_IO)) {
/* Probably reselected */
NCR5380_write(SELECT_ENABLE_REG, 0);
@@ -1710,7 +1691,7 @@ timeout:
return -1;
}

-#if defined(REAL_DMA)
+
/*
* Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
* unsigned char *phase, int *count, unsigned char **data)
@@ -1819,7 +1800,6 @@ static int NCR5380_transfer_dma(struct S

return 0;
}
-#endif /* defined(REAL_DMA) */

/*
* Function : NCR5380_information_transfer (struct Scsi_Host *instance)
@@ -1866,7 +1846,6 @@ static void NCR5380_information_transfer
}
#if defined(CONFIG_SUN3)
if (phase == PHASE_CMDOUT) {
-#if defined(REAL_DMA)
void *d;
unsigned long count;

@@ -1885,7 +1864,6 @@ static void NCR5380_information_transfer
sun3_dma_setup_done = cmd;
}
}
-#endif
#ifdef SUN3_SCSI_VME
dregs->csr |= CSR_INTR;
#endif
@@ -1943,12 +1921,6 @@ static void NCR5380_information_transfer
* in an unconditional loop.
*/

- /* ++roman: I suggest, this should be
- * #if def(REAL_DMA)
- * instead of leaving REAL_DMA out.
- */
-
-#if defined(REAL_DMA)
#if !defined(CONFIG_SUN3)
transfersize = 0;
if (!cmd->device->borken)
@@ -1972,21 +1944,9 @@ static void NCR5380_information_transfer
do_abort(instance);
cmd->result = DID_ERROR << 16;
/* XXX - need to source or sink data here, as appropriate */
- } else {
-#ifdef REAL_DMA
- /* ++roman: When using real DMA,
- * information_transfer() should return after
- * starting DMA since it has nothing more to
- * do.
- */
+ } else
return;
-#else
- cmd->SCp.this_residual -= transfersize - len;
-#endif
- }
- } else
-#endif /* defined(REAL_DMA) */
- {
+ } else {
/* Break up transfer into 3 ms chunks,
* presuming 6 accesses per handshake.
*/
@@ -1997,7 +1957,7 @@ static void NCR5380_information_transfer
(unsigned char **)&cmd->SCp.ptr);
cmd->SCp.this_residual -= transfersize - len;
}
-#if defined(CONFIG_SUN3) && defined(REAL_DMA)
+#if defined(CONFIG_SUN3)
/* if we had intended to dma that command clear it */
if (sun3_dma_setup_done == cmd)
sun3_dma_setup_done = NULL;
@@ -2305,7 +2265,7 @@ static void NCR5380_reselect(struct Scsi
return;
}

-#if defined(CONFIG_SUN3) && defined(REAL_DMA)
+#if defined(CONFIG_SUN3)
/* acknowledge toggle to MSGIN */
NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(PHASE_MSGIN));

@@ -2392,7 +2352,7 @@ static void NCR5380_reselect(struct Scsi
return;
}

-#if defined(CONFIG_SUN3) && defined(REAL_DMA)
+#if defined(CONFIG_SUN3)
/* engage dma setup for the command we just saw */
{
void *d;
@@ -2555,9 +2515,7 @@ static int NCR5380_abort(struct scsi_cmn
if (hostdata->connected == cmd) {
dsprintk(NDEBUG_ABORT, instance, "abort: cmd %p is connected\n", cmd);
hostdata->connected = NULL;
-#ifdef REAL_DMA
hostdata->dma_len = 0;
-#endif
if (do_abort(instance)) {
set_host_byte(cmd, DID_ERROR);
complete_cmd(instance, cmd);
@@ -2664,9 +2622,7 @@ static int NCR5380_bus_reset(struct scsi
#endif
for (i = 0; i < 8; ++i)
hostdata->busy[i] = 0;
-#ifdef REAL_DMA
hostdata->dma_len = 0;
-#endif

queue_work(hostdata->work_q, &hostdata->main_task);
maybe_release_dma_irq(instance);
Index: linux/drivers/scsi/atari_scsi.c
===================================================================
--- linux.orig/drivers/scsi/atari_scsi.c 2016-03-23 21:05:16.000000000 +1100
+++ linux/drivers/scsi/atari_scsi.c 2016-03-23 21:09:22.000000000 +1100
@@ -85,7 +85,6 @@

/* Definitions for the core NCR5380 driver. */

-#define REAL_DMA
#define SUPPORT_TAGS
#define MAX_TAGS 32
#define DMA_MIN_SIZE 32
@@ -159,14 +158,11 @@ static inline unsigned long SCSI_DMA_GET
return adr;
}

-#ifdef REAL_DMA
static void atari_scsi_fetch_restbytes(void);
-#endif

static unsigned char (*atari_scsi_reg_read)(unsigned char reg);
static void (*atari_scsi_reg_write)(unsigned char reg, unsigned char value);

-#ifdef REAL_DMA
static unsigned long atari_dma_residual, atari_dma_startaddr;
static short atari_dma_active;
/* pointer to the dribble buffer */
@@ -185,7 +181,6 @@ static char *atari_dma_orig_addr;
/* mask for address bits that can't be used with the ST-DMA */
static unsigned long atari_dma_stram_mask;
#define STRAM_ADDR(a) (((a) & atari_dma_stram_mask) == 0)
-#endif

static int setup_can_queue = -1;
module_param(setup_can_queue, int, 0);
@@ -201,8 +196,6 @@ static int setup_toshiba_delay = -1;
module_param(setup_toshiba_delay, int, 0);


-#if defined(REAL_DMA)
-
static int scsi_dma_is_ignored_buserr(unsigned char dma_stat)
{
int i;
@@ -255,12 +248,9 @@ static void scsi_dma_buserr(int irq, voi
}
#endif

-#endif
-

static irqreturn_t scsi_tt_intr(int irq, void *dev)
{
-#ifdef REAL_DMA
struct Scsi_Host *instance = dev;
struct NCR5380_hostdata *hostdata = shost_priv(instance);
int dma_stat;
@@ -342,8 +332,6 @@ static irqreturn_t scsi_tt_intr(int irq,
tt_scsi_dma.dma_ctrl = 0;
}

-#endif /* REAL_DMA */
-
NCR5380_intr(irq, dev);

return IRQ_HANDLED;
@@ -352,7 +340,6 @@ static irqreturn_t scsi_tt_intr(int irq,

static irqreturn_t scsi_falcon_intr(int irq, void *dev)
{
-#ifdef REAL_DMA
struct Scsi_Host *instance = dev;
struct NCR5380_hostdata *hostdata = shost_priv(instance);
int dma_stat;
@@ -405,15 +392,12 @@ static irqreturn_t scsi_falcon_intr(int
atari_dma_orig_addr = NULL;
}

-#endif /* REAL_DMA */
-
NCR5380_intr(irq, dev);

return IRQ_HANDLED;
}


-#ifdef REAL_DMA
static void atari_scsi_fetch_restbytes(void)
{
int nr;
@@ -436,7 +420,6 @@ static void atari_scsi_fetch_restbytes(v
*dst++ = *src++;
}
}
-#endif /* REAL_DMA */


/* This function releases the lock on the DMA chip if there is no
@@ -508,8 +491,6 @@ __setup("atascsi=", atari_scsi_setup);
#endif /* !MODULE */


-#if defined(REAL_DMA)
-
static unsigned long atari_scsi_dma_setup(struct Scsi_Host *instance,
void *data, unsigned long count,
int dir)
@@ -703,9 +684,6 @@ static unsigned long atari_dma_xfer_len(
}


-#endif /* REAL_DMA */
-
-
/* NCR5380 register access functions
*
* There are separate functions for TT and Falcon, because the access
@@ -745,7 +723,6 @@ static int atari_scsi_bus_reset(struct s

local_irq_save(flags);

-#ifdef REAL_DMA
/* Abort a maybe active DMA transfer */
if (IS_A_TT()) {
tt_scsi_dma.dma_ctrl = 0;
@@ -754,7 +731,6 @@ static int atari_scsi_bus_reset(struct s
atari_dma_active = 0;
atari_dma_orig_addr = NULL;
}
-#endif

rv = NCR5380_bus_reset(cmd);

@@ -850,8 +826,6 @@ static int __init atari_scsi_probe(struc
}
}

-
-#ifdef REAL_DMA
/* If running on a Falcon and if there's TT-Ram (i.e., more than one
* memory block, since there's always ST-Ram in a Falcon), then
* allocate a STRAM_BUFFER_SIZE byte dribble buffer for transfers
@@ -867,7 +841,6 @@ static int __init atari_scsi_probe(struc
atari_dma_phys_buffer = atari_stram_to_phys(atari_dma_buffer);
atari_dma_orig_addr = 0;
}
-#endif

instance = scsi_host_alloc(&atari_scsi_template,
sizeof(struct NCR5380_hostdata));
@@ -897,7 +870,7 @@ static int __init atari_scsi_probe(struc
goto fail_irq;
}
tt_mfp.active_edge |= 0x80; /* SCSI int on L->H */
-#ifdef REAL_DMA
+
tt_scsi_dma.dma_ctrl = 0;
atari_dma_residual = 0;

@@ -919,17 +892,14 @@ static int __init atari_scsi_probe(struc

hostdata->read_overruns = 4;
}
-#endif
} else {
/* Nothing to do for the interrupt: the ST-DMA is initialized
* already.
*/
-#ifdef REAL_DMA
atari_dma_residual = 0;
atari_dma_active = 0;
atari_dma_stram_mask = (ATARIHW_PRESENT(EXTD_DMA) ? 0x00000000
: 0xff000000);
-#endif
}

NCR5380_maybe_reset_bus(instance);
Index: linux/drivers/scsi/sun3_scsi.c
===================================================================
--- linux.orig/drivers/scsi/sun3_scsi.c 2016-03-23 21:05:16.000000000 +1100
+++ linux/drivers/scsi/sun3_scsi.c 2016-03-23 21:09:22.000000000 +1100
@@ -38,7 +38,6 @@

/* Definitions for the core NCR5380 driver. */

-#define REAL_DMA
/* #define SUPPORT_TAGS */
/* minimum number of bytes to do dma on */
#define DMA_MIN_SIZE 129
@@ -527,15 +526,9 @@ static int __init sun3_scsi_probe(struct
error = request_irq(instance->irq, scsi_sun3_intr, 0,
"NCR5380", instance);
if (error) {
-#ifdef REAL_DMA
pr_err(PFX "scsi%d: IRQ %d not free, bailing out\n",
instance->host_no, instance->irq);
goto fail_irq;
-#else
- pr_warn(PFX "scsi%d: IRQ %d not free, interrupts disabled\n",
- instance->host_no, instance->irq);
- instance->irq = NO_IRQ;
-#endif
}

dregs->csr = 0;
@@ -565,8 +558,7 @@ static int __init sun3_scsi_probe(struct
return 0;

fail_host:
- if (instance->irq != NO_IRQ)
- free_irq(instance->irq, instance);
+ free_irq(instance->irq, instance);
fail_irq:
NCR5380_exit(instance);
fail_init:
@@ -583,8 +575,7 @@ static int __exit sun3_scsi_remove(struc
struct Scsi_Host *instance = platform_get_drvdata(pdev);

scsi_remove_host(instance);
- if (instance->irq != NO_IRQ)
- free_irq(instance->irq, instance);
+ free_irq(instance->irq, instance);
NCR5380_exit(instance);
scsi_host_put(instance);
if (udc_regs)