diff mbox series

[07/28] 53c700: improve non-coherent DMA handling

Message ID 20200819065555.1802761-8-hch@lst.de (mailing list archive)
State Not Applicable
Headers show
Series [01/28] mm: turn alloc_pages into an inline function | expand

Commit Message

Christoph Hellwig Aug. 19, 2020, 6:55 a.m. UTC 
Switch the 53c700 driver to only use non-coherent descriptor memory if it
really has to because dma_alloc_coherent fails.  This doesn't matter for
any of the platforms it runs on currently, but that will change soon.

To help with this two new helpers to transfer ownership to and from the
device are added that abstract the syncing of the non-coherent memory.
The two current bidirectional cases are mapped to transfers to the
device, as that appears to what they are used for.  Note that for parisc,
which is the only architecture this driver needs to use non-coherent
memory on, the direction argument of dma_cache_sync is ignored, so this
will not change behavior in any way.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/scsi/53c700.c | 113 +++++++++++++++++++++++-------------------
 drivers/scsi/53c700.h |   9 ++--
 2 files changed, 68 insertions(+), 54 deletions(-)

Comments

James Bottomley Sept. 1, 2020, 2:52 p.m. UTC | #1 
On Wed, 2020-08-19 at 08:55 +0200, Christoph Hellwig wrote:
> Switch the 53c700 driver to only use non-coherent descriptor memory
> if it really has to because dma_alloc_coherent fails.  This doesn't
> matter for any of the platforms it runs on currently, but that will
> change soon.
> 
> To help with this two new helpers to transfer ownership to and from
> the device are added that abstract the syncing of the non-coherent
> memory. The two current bidirectional cases are mapped to transfers
> to the device, as that appears to what they are used for.  Note that
> for parisc, which is the only architecture this driver needs to use
> non-coherent memory on, the direction argument of dma_cache_sync is
> ignored, so this will not change behavior in any way.

I think this looks mostly OK, except for one misnamed parameter below. 
Unfortunately, the last non-coherent parisc was the 700 series and I no
longer own a box, so I can't test that part of it (I can fire up the
C360 to test it on a coherent arch).

[...]
> diff --git a/drivers/scsi/53c700.h b/drivers/scsi/53c700.h
> index 05fe439b66afe5..0f545b05fe611d 100644
> --- a/drivers/scsi/53c700.h
> +++ b/drivers/scsi/53c700.h
> @@ -209,6 +209,7 @@ struct NCR_700_Host_Parameters {
>  #endif
>  	__u32	chip710:1;	/* set if really a 710 not
> 700 */
>  	__u32	burst_length:4;	/* set to 0 to disable
> 710 bursting */
> +	__u32	noncoherent:1;	/* needs to use non-
> coherent DMA */
>  
>  	/* NOTHING BELOW HERE NEEDS ALTERING */
>  	__u32	fast:1;		/* if we can alter the
> SCSI bus clock
> @@ -429,7 +430,7 @@ struct NCR_700_Host_Parameters {
>  	for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32));
> i++) { \
>  		__u32 val =
> bS_to_cpu((script)[A_##symbol##_used[i]]) + da; \
>  		(script)[A_##symbol##_used[i]] = bS_to_host(val); \
> -		dma_cache_sync((dev),
> &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
> +		dma_sync_to_dev((dev),
> &(script)[A_##symbol##_used[i]], 4); \
>  		DEBUG((" script, patching %s at %d to %pad\n", \
>  		       #symbol, A_##symbol##_used[i], &da)); \
>  	} \
> @@ -441,7 +442,7 @@ struct NCR_700_Host_Parameters {
>  	dma_addr_t da = value; \
>  	for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32));
> i++) { \
>  		(script)[A_##symbol##_used[i]] = bS_to_host(da); \
> -		dma_cache_sync((dev),
> &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
> +		dma_sync_to_dev((dev),
> &(script)[A_##symbol##_used[i]], 4); \
>  		DEBUG((" script, patching %s at %d to %pad\n", \
>  		       #symbol, A_##symbol##_used[i], &da)); \
>  	} \
> @@ -456,7 +457,7 @@ struct NCR_700_Host_Parameters {
>  		val &= 0xff00ffff; \
>  		val |= ((value) & 0xff) << 16; \
>  		(script)[A_##symbol##_used[i]] = bS_to_host(val); \
> -		dma_cache_sync((dev),
> &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
> +		dma_sync_to_dev((dev),
> &(script)[A_##symbol##_used[i]], 4); \
>  		DEBUG((" script, patching ID field %s at %d to
> 0x%x\n", \
>  		       #symbol, A_##symbol##_used[i], val)); \
>  	} \
> @@ -470,7 +471,7 @@ struct NCR_700_Host_Parameters {
>  		val &= 0xffff0000; \
>  		val |= ((value) & 0xffff); \
>  		(script)[A_##symbol##_used[i]] = bS_to_host(val); \
> -		dma_cache_sync((dev),
> &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
> +		dma_sync_to_dev((dev),
> &(script)[A_##symbol##_used[i]], 4); \
>  		DEBUG((" script, patching short field %s at %d to
> 0x%x\n", \
>  		       #symbol, A_##symbol##_used[i], val)); \
>  	} \

These macro arguments need updating.  Since you changed the input from
hostdata->dev to hostdata, leaving the macro argument as dev is simply
misleading.  It needs to become hostdata or h.

James
Matthew Wilcox Sept. 1, 2020, 3:05 p.m. UTC | #2 
On Tue, Sep 01, 2020 at 07:52:40AM -0700, James Bottomley wrote:
> I think this looks mostly OK, except for one misnamed parameter below. 
> Unfortunately, the last non-coherent parisc was the 700 series and I no
> longer own a box, so I can't test that part of it (I can fire up the
> C360 to test it on a coherent arch).

I have a 715/50 that probably hasn't been powered on in 15 years if you
need something that old to test on (I believe the 725/100 uses the 7100LC
and so is coherent).  I'll need to set up a cross-compiler ...
James Bottomley Sept. 1, 2020, 3:22 p.m. UTC | #3 
On Tue, 2020-09-01 at 16:05 +0100, Matthew Wilcox wrote:
> On Tue, Sep 01, 2020 at 07:52:40AM -0700, James Bottomley wrote:
> > I think this looks mostly OK, except for one misnamed parameter
> > below. Unfortunately, the last non-coherent parisc was the 700
> > series and I no longer own a box, so I can't test that part of it
> > (I can fire up the C360 to test it on a coherent arch).
> 
> I have a 715/50 that probably hasn't been powered on in 15 years if
> you need something that old to test on (I believe the 725/100 uses
> the 7100LC and so is coherent).  I'll need to set up a cross-compiler 
> ...

I'm not going to say no to actual testing, but it's going to be a world
of pain getting something so old going.  I do have a box of older
systems I keep for architectural testing that I need to rummage around
in ... I just have a vague memory that my 715 actually caught fire a
decade ago and had to be disposed of.

James
Helge Deller Sept. 1, 2020, 4:21 p.m. UTC | #4 
On 01.09.20 17:22, James Bottomley wrote:
> On Tue, 2020-09-01 at 16:05 +0100, Matthew Wilcox wrote:
>> On Tue, Sep 01, 2020 at 07:52:40AM -0700, James Bottomley wrote:
>>> I think this looks mostly OK, except for one misnamed parameter
>>> below. Unfortunately, the last non-coherent parisc was the 700
>>> series and I no longer own a box, so I can't test that part of it
>>> (I can fire up the C360 to test it on a coherent arch).
>>
>> I have a 715/50 that probably hasn't been powered on in 15 years if
>> you need something that old to test on (I believe the 725/100 uses
>> the 7100LC and so is coherent).  I'll need to set up a cross-compiler
>> ...
>
> I'm not going to say no to actual testing, but it's going to be a world
> of pain getting something so old going.  I do have a box of older
> systems I keep for architectural testing that I need to rummage around
> in ... I just have a vague memory that my 715 actually caught fire a
> decade ago and had to be disposed of.

I still have a zoo of machines running for such testing, including a
715/64 and two 730.
I'm going to test this git tree on the 715/64:
git://git.infradead.org/users/hch/misc.git dma_alloc_pages

Helge
Helge Deller Sept. 1, 2020, 4:41 p.m. UTC | #5 
On 01.09.20 18:21, Helge Deller wrote:
> On 01.09.20 17:22, James Bottomley wrote:
>> On Tue, 2020-09-01 at 16:05 +0100, Matthew Wilcox wrote:
>>> On Tue, Sep 01, 2020 at 07:52:40AM -0700, James Bottomley wrote:
>>>> I think this looks mostly OK, except for one misnamed parameter
>>>> below. Unfortunately, the last non-coherent parisc was the 700
>>>> series and I no longer own a box, so I can't test that part of it
>>>> (I can fire up the C360 to test it on a coherent arch).
>>>
>>> I have a 715/50 that probably hasn't been powered on in 15 years if
>>> you need something that old to test on (I believe the 725/100 uses
>>> the 7100LC and so is coherent).  I'll need to set up a cross-compiler
>>> ...
>>
>> I'm not going to say no to actual testing, but it's going to be a world
>> of pain getting something so old going.  I do have a box of older
>> systems I keep for architectural testing that I need to rummage around
>> in ... I just have a vague memory that my 715 actually caught fire a
>> decade ago and had to be disposed of.
>
> I still have a zoo of machines running for such testing, including a
> 715/64 and two 730.
> I'm going to test this git tree on the 715/64:
> git://git.infradead.org/users/hch/misc.git dma_alloc_pages

This tree boots nicely (up to a command prompt with i82596 nic working):

53c700: Version 2.8 By James.Bottomley@HansenPartnership.com
scsi0: 53c710 rev 2
scsi host0: LASI SCSI 53c700
scsi 0:0:6:0: Direct-Access     QUANTUM  FIREBALL_TM3200S 300X PQ: 0 ANSI: 2
scsi target0:0:6: Beginning Domain Validation
scsi 0:0:6:0: tag#56 Enabling Tag Command Queuing
scsi target0:0:6: asynchronous
scsi target0:0:6: FAST-10 SCSI 10.0 MB/s ST (100 ns, offset 8)
scsi target0:0:6: Domain Validation skipping write tests
scsi target0:0:6: Ending Domain Validation
scsi 0:0:6:1: tag#63 Disabling Tag Command Queuing
st: Version 20160209, fixed bufsize 32768, s/g segs 256
sd 0:0:6:0: Power-on or device reset occurred
sd 0:0:6:0: Attached scsi generic sg0 type 0
LASI 82596 driver - Revision: 1.30
Found i82596 at 0xf0107000, IRQ 17
eth0: 82596 at 0xf0107000, 08:00:09:c2:9e:60 IRQ 17.
sd 0:0:6:0: [sda] 6281856 512-byte logical blocks: (3.22 GB/3.00 GiB)
sd 0:0:6:0: [sda] Write Protect is off

Christoph, you may add a
Tested-by: Helge Deller <deller@gmx.de> # parisc
to the series.

Helge
Matthew Wilcox Sept. 1, 2020, 4:53 p.m. UTC | #6 
On Tue, Sep 01, 2020 at 06:41:12PM +0200, Helge Deller wrote:
> > I still have a zoo of machines running for such testing, including a
> > 715/64 and two 730.
> > I'm going to test this git tree on the 715/64:

The 715/64 is a 7100LC machine though.  I think you need to boot on
the 730 to test the non-coherent path.
Helge Deller Sept. 2, 2020, 3 p.m. UTC | #7 
Hi Willy,

On 01.09.20 18:53, Matthew Wilcox wrote:
> On Tue, Sep 01, 2020 at 06:41:12PM +0200, Helge Deller wrote:
>>> I still have a zoo of machines running for such testing, including a
>>> 715/64 and two 730.
>>> I'm going to test this git tree on the 715/64:
>
> The 715/64 is a 7100LC machine though.  I think you need to boot on
> the 730 to test the non-coherent path.

Just tested the 730, and it works as well.

Helge
diff mbox series

Patch

diff --git a/drivers/scsi/53c700.c b/drivers/scsi/53c700.c
index 461b3babb601ef..b197ed9399e2e0 100644
--- a/drivers/scsi/53c700.c
+++ b/drivers/scsi/53c700.c
@@ -269,6 +269,20 @@  NCR_700_get_SXFER(struct scsi_device *SDp)
 					      spi_period(SDp->sdev_target));
 }
 
+static inline void dma_sync_to_dev(struct NCR_700_Host_Parameters *h,
+		void *addr, size_t size)
+{
+	if (h->noncoherent)
+		dma_cache_sync(h->dev, addr, size, DMA_TO_DEVICE);
+}
+
+static inline void dma_sync_from_dev(struct NCR_700_Host_Parameters *h,
+		void *addr, size_t size)
+{
+	if (h->noncoherent)
+		dma_cache_sync(h->dev, addr, size, DMA_FROM_DEVICE);
+}
+
 struct Scsi_Host *
 NCR_700_detect(struct scsi_host_template *tpnt,
 	       struct NCR_700_Host_Parameters *hostdata, struct device *dev)
@@ -283,9 +297,13 @@  NCR_700_detect(struct scsi_host_template *tpnt,
 	if(tpnt->sdev_attrs == NULL)
 		tpnt->sdev_attrs = NCR_700_dev_attrs;
 
-	memory = dma_alloc_attrs(dev, TOTAL_MEM_SIZE, &pScript,
-				 GFP_KERNEL, DMA_ATTR_NON_CONSISTENT);
-	if(memory == NULL) {
+	memory = dma_alloc_coherent(dev, TOTAL_MEM_SIZE, &pScript, GFP_KERNEL);
+	if (!memory) {
+		hostdata->noncoherent = 1;
+		memory = dma_alloc_attrs(dev, TOTAL_MEM_SIZE, &pScript,
+					 GFP_KERNEL, DMA_ATTR_NON_CONSISTENT);
+	}
+	if (!memory) {
 		printk(KERN_ERR "53c700: Failed to allocate memory for driver, detaching\n");
 		return NULL;
 	}
@@ -339,11 +357,11 @@  NCR_700_detect(struct scsi_host_template *tpnt,
 	for (j = 0; j < PATCHES; j++)
 		script[LABELPATCHES[j]] = bS_to_host(pScript + SCRIPT[LABELPATCHES[j]]);
 	/* now patch up fixed addresses. */
-	script_patch_32(hostdata->dev, script, MessageLocation,
+	script_patch_32(hostdata, script, MessageLocation,
 			pScript + MSGOUT_OFFSET);
-	script_patch_32(hostdata->dev, script, StatusAddress,
+	script_patch_32(hostdata, script, StatusAddress,
 			pScript + STATUS_OFFSET);
-	script_patch_32(hostdata->dev, script, ReceiveMsgAddress,
+	script_patch_32(hostdata, script, ReceiveMsgAddress,
 			pScript + MSGIN_OFFSET);
 
 	hostdata->script = script;
@@ -395,8 +413,12 @@  NCR_700_release(struct Scsi_Host *host)
 	struct NCR_700_Host_Parameters *hostdata = 
 		(struct NCR_700_Host_Parameters *)host->hostdata[0];
 
-	dma_free_attrs(hostdata->dev, TOTAL_MEM_SIZE, hostdata->script,
-		       hostdata->pScript, DMA_ATTR_NON_CONSISTENT);
+	if (hostdata->noncoherent)
+		dma_free_attrs(hostdata->dev, TOTAL_MEM_SIZE, hostdata->script,
+			       hostdata->pScript, DMA_ATTR_NON_CONSISTENT);
+	else
+		dma_free_coherent(hostdata->dev, TOTAL_MEM_SIZE,
+				  hostdata->script, hostdata->pScript);
 	return 1;
 }
 
@@ -804,8 +826,8 @@  process_extended_message(struct Scsi_Host *host,
 			shost_printk(KERN_WARNING, host,
 				"Unexpected SDTR msg\n");
 			hostdata->msgout[0] = A_REJECT_MSG;
-			dma_cache_sync(hostdata->dev, hostdata->msgout, 1, DMA_TO_DEVICE);
-			script_patch_16(hostdata->dev, hostdata->script,
+			dma_sync_to_dev(hostdata, hostdata->msgout, 1);
+			script_patch_16(hostdata, hostdata->script,
 			                MessageCount, 1);
 			/* SendMsgOut returns, so set up the return
 			 * address */
@@ -817,9 +839,8 @@  process_extended_message(struct Scsi_Host *host,
 		printk(KERN_INFO "scsi%d: (%d:%d), Unsolicited WDTR after CMD, Rejecting\n",
 		       host->host_no, pun, lun);
 		hostdata->msgout[0] = A_REJECT_MSG;
-		dma_cache_sync(hostdata->dev, hostdata->msgout, 1, DMA_TO_DEVICE);
-		script_patch_16(hostdata->dev, hostdata->script, MessageCount,
-		                1);
+		dma_sync_to_dev(hostdata, hostdata->msgout, 1);
+		script_patch_16(hostdata, hostdata->script, MessageCount, 1);
 		resume_offset = hostdata->pScript + Ent_SendMessageWithATN;
 
 		break;
@@ -832,9 +853,8 @@  process_extended_message(struct Scsi_Host *host,
 		printk("\n");
 		/* just reject it */
 		hostdata->msgout[0] = A_REJECT_MSG;
-		dma_cache_sync(hostdata->dev, hostdata->msgout, 1, DMA_TO_DEVICE);
-		script_patch_16(hostdata->dev, hostdata->script, MessageCount,
-		                1);
+		dma_sync_to_dev(hostdata, hostdata->msgout, 1);
+		script_patch_16(hostdata, hostdata->script, MessageCount, 1);
 		/* SendMsgOut returns, so set up the return
 		 * address */
 		resume_offset = hostdata->pScript + Ent_SendMessageWithATN;
@@ -917,9 +937,8 @@  process_message(struct Scsi_Host *host,	struct NCR_700_Host_Parameters *hostdata
 		printk("\n");
 		/* just reject it */
 		hostdata->msgout[0] = A_REJECT_MSG;
-		dma_cache_sync(hostdata->dev, hostdata->msgout, 1, DMA_TO_DEVICE);
-		script_patch_16(hostdata->dev, hostdata->script, MessageCount,
-		                1);
+		dma_sync_to_dev(hostdata, hostdata->msgout, 1);
+		script_patch_16(hostdata, hostdata->script, MessageCount, 1);
 		/* SendMsgOut returns, so set up the return
 		 * address */
 		resume_offset = hostdata->pScript + Ent_SendMessageWithATN;
@@ -928,7 +947,7 @@  process_message(struct Scsi_Host *host,	struct NCR_700_Host_Parameters *hostdata
 	}
 	NCR_700_writel(temp, host, TEMP_REG);
 	/* set us up to receive another message */
-	dma_cache_sync(hostdata->dev, hostdata->msgin, MSG_ARRAY_SIZE, DMA_FROM_DEVICE);
+	dma_sync_from_dev(hostdata, hostdata->msgin, MSG_ARRAY_SIZE);
 	return resume_offset;
 }
 
@@ -1008,8 +1027,8 @@  process_script_interrupt(__u32 dsps, __u32 dsp, struct scsi_cmnd *SCp,
 				slot->SG[1].ins = bS_to_host(SCRIPT_RETURN);
 				slot->SG[1].pAddr = 0;
 				slot->resume_offset = hostdata->pScript;
-				dma_cache_sync(hostdata->dev, slot->SG, sizeof(slot->SG[0])*2, DMA_TO_DEVICE);
-				dma_cache_sync(hostdata->dev, SCp->sense_buffer, SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
+				dma_sync_to_dev(hostdata, slot->SG, sizeof(slot->SG[0])*2);
+				dma_sync_from_dev(hostdata, SCp->sense_buffer, SCSI_SENSE_BUFFERSIZE);
 
 				/* queue the command for reissue */
 				slot->state = NCR_700_SLOT_QUEUED;
@@ -1129,11 +1148,11 @@  process_script_interrupt(__u32 dsps, __u32 dsp, struct scsi_cmnd *SCp,
 			hostdata->cmd = slot->cmnd;
 
 			/* re-patch for this command */
-			script_patch_32_abs(hostdata->dev, hostdata->script,
+			script_patch_32_abs(hostdata, hostdata->script,
 			                    CommandAddress, slot->pCmd);
-			script_patch_16(hostdata->dev, hostdata->script,
+			script_patch_16(hostdata, hostdata->script,
 					CommandCount, slot->cmnd->cmd_len);
-			script_patch_32_abs(hostdata->dev, hostdata->script,
+			script_patch_32_abs(hostdata, hostdata->script,
 			                    SGScriptStartAddress,
 					    to32bit(&slot->pSG[0].ins));
 
@@ -1144,14 +1163,14 @@  process_script_interrupt(__u32 dsps, __u32 dsp, struct scsi_cmnd *SCp,
 			 * should therefore always clear ACK */
 			NCR_700_writeb(NCR_700_get_SXFER(hostdata->cmd->device),
 				       host, SXFER_REG);
-			dma_cache_sync(hostdata->dev, hostdata->msgin,
-				       MSG_ARRAY_SIZE, DMA_FROM_DEVICE);
-			dma_cache_sync(hostdata->dev, hostdata->msgout,
-				       MSG_ARRAY_SIZE, DMA_TO_DEVICE);
+			dma_sync_from_dev(hostdata, hostdata->msgin,
+				       MSG_ARRAY_SIZE);
+			dma_sync_to_dev(hostdata, hostdata->msgout,
+				       MSG_ARRAY_SIZE);
 			/* I'm just being paranoid here, the command should
 			 * already have been flushed from the cache */
-			dma_cache_sync(hostdata->dev, slot->cmnd->cmnd,
-				       slot->cmnd->cmd_len, DMA_TO_DEVICE);
+			dma_sync_to_dev(hostdata, slot->cmnd->cmnd,
+				       slot->cmnd->cmd_len);
 
 
 			
@@ -1214,8 +1233,7 @@  process_script_interrupt(__u32 dsps, __u32 dsp, struct scsi_cmnd *SCp,
 		hostdata->reselection_id = reselection_id;
 		/* just in case we have a stale simple tag message, clear it */
 		hostdata->msgin[1] = 0;
-		dma_cache_sync(hostdata->dev, hostdata->msgin,
-			       MSG_ARRAY_SIZE, DMA_BIDIRECTIONAL);
+		dma_sync_to_dev(hostdata, hostdata->msgin, MSG_ARRAY_SIZE);
 		if(hostdata->tag_negotiated & (1<<reselection_id)) {
 			resume_offset = hostdata->pScript + Ent_GetReselectionWithTag;
 		} else {
@@ -1329,8 +1347,7 @@  process_selection(struct Scsi_Host *host, __u32 dsp)
 	hostdata->cmd = NULL;
 	/* clear any stale simple tag message */
 	hostdata->msgin[1] = 0;
-	dma_cache_sync(hostdata->dev, hostdata->msgin, MSG_ARRAY_SIZE,
-		       DMA_BIDIRECTIONAL);
+	dma_sync_to_dev(hostdata, hostdata->msgin, MSG_ARRAY_SIZE);
 
 	if(id == 0xff) {
 		/* Selected as target, Ignore */
@@ -1427,30 +1444,26 @@  NCR_700_start_command(struct scsi_cmnd *SCp)
 		NCR_700_set_flag(SCp->device, NCR_700_DEV_BEGIN_SYNC_NEGOTIATION);
 	}
 
-	script_patch_16(hostdata->dev, hostdata->script, MessageCount, count);
-
+	script_patch_16(hostdata, hostdata->script, MessageCount, count);
 
-	script_patch_ID(hostdata->dev, hostdata->script,
-			Device_ID, 1<<scmd_id(SCp));
+	script_patch_ID(hostdata, hostdata->script, Device_ID, 1<<scmd_id(SCp));
 
-	script_patch_32_abs(hostdata->dev, hostdata->script, CommandAddress,
+	script_patch_32_abs(hostdata, hostdata->script, CommandAddress,
 			    slot->pCmd);
-	script_patch_16(hostdata->dev, hostdata->script, CommandCount,
-	                SCp->cmd_len);
+	script_patch_16(hostdata, hostdata->script, CommandCount, SCp->cmd_len);
 	/* finally plumb the beginning of the SG list into the script
 	 * */
-	script_patch_32_abs(hostdata->dev, hostdata->script,
+	script_patch_32_abs(hostdata, hostdata->script,
 	                    SGScriptStartAddress, to32bit(&slot->pSG[0].ins));
 	NCR_700_clear_fifo(SCp->device->host);
 
 	if(slot->resume_offset == 0)
 		slot->resume_offset = hostdata->pScript;
 	/* now perform all the writebacks and invalidates */
-	dma_cache_sync(hostdata->dev, hostdata->msgout, count, DMA_TO_DEVICE);
-	dma_cache_sync(hostdata->dev, hostdata->msgin, MSG_ARRAY_SIZE,
-		       DMA_FROM_DEVICE);
-	dma_cache_sync(hostdata->dev, SCp->cmnd, SCp->cmd_len, DMA_TO_DEVICE);
-	dma_cache_sync(hostdata->dev, hostdata->status, 1, DMA_FROM_DEVICE);
+	dma_sync_to_dev(hostdata, hostdata->msgout, count);
+	dma_sync_from_dev(hostdata, hostdata->msgin, MSG_ARRAY_SIZE);
+	dma_sync_to_dev(hostdata, SCp->cmnd, SCp->cmd_len);
+	dma_sync_from_dev(hostdata, hostdata->status, 1);
 
 	/* set the synchronous period/offset */
 	NCR_700_writeb(NCR_700_get_SXFER(SCp->device),
@@ -1626,7 +1639,7 @@  NCR_700_intr(int irq, void *dev_id)
 					slot->SG[i].ins = bS_to_host(SCRIPT_NOP);
 					slot->SG[i].pAddr = 0;
 				}
-				dma_cache_sync(hostdata->dev, slot->SG, sizeof(slot->SG), DMA_TO_DEVICE);
+				dma_sync_to_dev(hostdata, slot->SG, sizeof(slot->SG));
 				/* and pretend we disconnected after
 				 * the command phase */
 				resume_offset = hostdata->pScript + Ent_MsgInDuringData;
@@ -1878,7 +1891,7 @@  NCR_700_queuecommand_lck(struct scsi_cmnd *SCp, void (*done)(struct scsi_cmnd *)
 		}
 		slot->SG[i].ins = bS_to_host(SCRIPT_RETURN);
 		slot->SG[i].pAddr = 0;
-		dma_cache_sync(hostdata->dev, slot->SG, sizeof(slot->SG), DMA_TO_DEVICE);
+		dma_sync_to_dev(hostdata, slot->SG, sizeof(slot->SG));
 		DEBUG((" SETTING %p to %x\n",
 		       (&slot->pSG[i].ins),
 		       slot->SG[i].ins));
diff --git a/drivers/scsi/53c700.h b/drivers/scsi/53c700.h
index 05fe439b66afe5..0f545b05fe611d 100644
--- a/drivers/scsi/53c700.h
+++ b/drivers/scsi/53c700.h
@@ -209,6 +209,7 @@  struct NCR_700_Host_Parameters {
 #endif
 	__u32	chip710:1;	/* set if really a 710 not 700 */
 	__u32	burst_length:4;	/* set to 0 to disable 710 bursting */
+	__u32	noncoherent:1;	/* needs to use non-coherent DMA */
 
 	/* NOTHING BELOW HERE NEEDS ALTERING */
 	__u32	fast:1;		/* if we can alter the SCSI bus clock
@@ -429,7 +430,7 @@  struct NCR_700_Host_Parameters {
 	for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32)); i++) { \
 		__u32 val = bS_to_cpu((script)[A_##symbol##_used[i]]) + da; \
 		(script)[A_##symbol##_used[i]] = bS_to_host(val); \
-		dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
+		dma_sync_to_dev((dev), &(script)[A_##symbol##_used[i]], 4); \
 		DEBUG((" script, patching %s at %d to %pad\n", \
 		       #symbol, A_##symbol##_used[i], &da)); \
 	} \
@@ -441,7 +442,7 @@  struct NCR_700_Host_Parameters {
 	dma_addr_t da = value; \
 	for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32)); i++) { \
 		(script)[A_##symbol##_used[i]] = bS_to_host(da); \
-		dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
+		dma_sync_to_dev((dev), &(script)[A_##symbol##_used[i]], 4); \
 		DEBUG((" script, patching %s at %d to %pad\n", \
 		       #symbol, A_##symbol##_used[i], &da)); \
 	} \
@@ -456,7 +457,7 @@  struct NCR_700_Host_Parameters {
 		val &= 0xff00ffff; \
 		val |= ((value) & 0xff) << 16; \
 		(script)[A_##symbol##_used[i]] = bS_to_host(val); \
-		dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
+		dma_sync_to_dev((dev), &(script)[A_##symbol##_used[i]], 4); \
 		DEBUG((" script, patching ID field %s at %d to 0x%x\n", \
 		       #symbol, A_##symbol##_used[i], val)); \
 	} \
@@ -470,7 +471,7 @@  struct NCR_700_Host_Parameters {
 		val &= 0xffff0000; \
 		val |= ((value) & 0xffff); \
 		(script)[A_##symbol##_used[i]] = bS_to_host(val); \
-		dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
+		dma_sync_to_dev((dev), &(script)[A_##symbol##_used[i]], 4); \
 		DEBUG((" script, patching short field %s at %d to 0x%x\n", \
 		       #symbol, A_##symbol##_used[i], val)); \
 	} \