[PATCH v2 41/72] ncr5380: Replace redundant flags with FLAG_NO_DMA_FIXUP

Finn Thain
2015-12-06T03:44:13Z

[-- Attachment #1: ncr5380-remove-FLAG_NCR53C400 --]
[-- Type: text/plain, Size: 7612 bytes --]

The flags DMA_WORKS_RIGHT, FLAG_NCR53C400 and FLAG_HAS_LAST_BYTE_SENT
all mean the same thing, i.e. the chip is not a 538[01]. (More recent
devices such as the 53C80 have a 'Last Byte Sent' bit in the Target
Command Register as well as other fixes for End-of-DMA errata.)

These flags have no additional meanings since previous cleanup patches
eliminated the NCR53C400 macro, moved g_NCR5380-specific code out of the
core driver and standardized interrupt handling.

Use the FLAG_NO_DMA_FIXUP flag to suppress End-of-DMA errata workarounds,
for those cards and drivers that make use of the TCR_LAST_BYTE_SENT bit.
Remove the old flags.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>

---
drivers/scsi/NCR5380.c | 68 +++++++++++++++--------------------------------
drivers/scsi/NCR5380.h | 4 --
drivers/scsi/dtc.c | 4 --
drivers/scsi/g_NCR5380.c | 2 -
4 files changed, 25 insertions(+), 53 deletions(-)

Index: linux/drivers/scsi/NCR5380.c
===================================================================
--- linux.orig/drivers/scsi/NCR5380.c 2015-12-06 12:30:32.000000000 +1100
+++ linux/drivers/scsi/NCR5380.c 2015-12-06 12:30:34.000000000 +1100
@@ -541,7 +541,7 @@ static void prepare_info(struct Scsi_Hos
instance->base, instance->irq,
instance->can_queue, instance->cmd_per_lun,
instance->sg_tablesize, instance->this_id,
- hostdata->flags & FLAG_NCR53C400 ? "NCR53C400 " : "",
+ hostdata->flags & FLAG_NO_DMA_FIXUP ? "NO_DMA_FIXUP " : "",
hostdata->flags & FLAG_DTC3181E ? "DTC3181E " : "",
hostdata->flags & FLAG_NO_PSEUDO_DMA ? "NO_PSEUDO_DMA " : "",
hostdata->flags & FLAG_TOSHIBA_DELAY ? "TOSHIBA_DELAY " : "",
@@ -702,6 +702,7 @@ static int NCR5380_init(struct Scsi_Host
hostdata->connected = NULL;
hostdata->issue_queue = NULL;
hostdata->disconnected_queue = NULL;
+ hostdata->flags = flags;

INIT_WORK(&hostdata->main_task, NCR5380_main);
hostdata->work_q = alloc_workqueue("ncr5380_%d",
@@ -710,12 +711,6 @@ static int NCR5380_init(struct Scsi_Host
if (!hostdata->work_q)
return -ENOMEM;

- /* The CHECK code seems to break the 53C400. Will check it later maybe */
- if (flags & FLAG_NCR53C400)
- hostdata->flags = FLAG_HAS_LAST_BYTE_SENT | flags;
- else
- hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT | flags;
-
hostdata->host = instance;

prepare_info(instance);
@@ -1609,7 +1604,7 @@ static int NCR5380_transfer_dma(struct S
* before the setting of DMA mode to after transfer of the last byte.
*/

- if (hostdata->flags & FLAG_NCR53C400)
+ if (hostdata->flags & FLAG_NO_DMA_FIXUP)
NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_MONITOR_BSY |
MR_ENABLE_EOP_INTR);
else
@@ -1729,14 +1724,9 @@ static int NCR5380_transfer_dma(struct S
return 0;
#else /* defined(REAL_DMA_POLL) */
if (p & SR_IO) {
-#ifdef DMA_WORKS_RIGHT
- foo = NCR5380_pread(instance, d, c);
-#else
- int diff = 1;
- if (hostdata->flags & FLAG_NCR53C400) {
- diff = 0;
- }
- if (!(foo = NCR5380_pread(instance, d, c - diff))) {
+ 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
@@ -1759,46 +1749,32 @@ static int NCR5380_transfer_dma(struct S
* byte.
*/

- if (!(hostdata->flags & FLAG_NCR53C400)) {
- while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ));
- /* Wait for clean handshake */
- while (NCR5380_read(STATUS_REG) & SR_REQ);
- d[c - 1] = NCR5380_read(INPUT_DATA_REG);
+ if (NCR5380_poll_politely(instance, BUS_AND_STATUS_REG,
+ BASR_DRQ, BASR_DRQ, HZ) < 0) {
+ foo = -1;
+ shost_printk(KERN_ERR, instance, "PDMA read: DRQ timeout\n");
+ }
+ if (NCR5380_poll_politely(instance, STATUS_REG,
+ SR_REQ, 0, HZ) < 0) {
+ foo = -1;
+ shost_printk(KERN_ERR, instance, "PDMA read: !REQ timeout\n");
}
+ d[c - 1] = NCR5380_read(INPUT_DATA_REG);
}
-#endif
} else {
-#ifdef DMA_WORKS_RIGHT
foo = NCR5380_pwrite(instance, d, c);
-#else
- int timeout;
- dprintk(NDEBUG_C400_PWRITE, "About to pwrite %d bytes\n", c);
- if (!(foo = NCR5380_pwrite(instance, d, c))) {
+ if (!foo && !(hostdata->flags & FLAG_NO_DMA_FIXUP)) {
/*
* Wait for the last byte to be sent. If REQ is being asserted for
* the byte we're interested, we'll ACK it and it will go false.
*/
- if (!(hostdata->flags & FLAG_HAS_LAST_BYTE_SENT)) {
- timeout = 20000;
- while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) && (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH));
-
- if (!timeout)
- dprintk(NDEBUG_LAST_BYTE_SENT, "scsi%d : timed out on last byte\n", instance->host_no);
-
- if (hostdata->flags & FLAG_CHECK_LAST_BYTE_SENT) {
- hostdata->flags &= ~FLAG_CHECK_LAST_BYTE_SENT;
- if (NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT) {
- hostdata->flags |= FLAG_HAS_LAST_BYTE_SENT;
- dprintk(NDEBUG_LAST_BYTE_SENT, "scsi%d : last byte sent works\n", instance->host_no);
- }
- }
- } else {
- dprintk(NDEBUG_C400_PWRITE, "Waiting for LASTBYTE\n");
- while (!(NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT));
- dprintk(NDEBUG_C400_PWRITE, "Got LASTBYTE\n");
+ if (NCR5380_poll_politely2(instance,
+ BUS_AND_STATUS_REG, BASR_DRQ, BASR_DRQ,
+ BUS_AND_STATUS_REG, BASR_PHASE_MATCH, 0, HZ) < 0) {
+ foo = -1;
+ shost_printk(KERN_ERR, instance, "PDMA write: DRQ and phase timeout\n");
}
}
-#endif
}
NCR5380_write(MODE_REG, MR_BASE);
NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
Index: linux/drivers/scsi/NCR5380.h
===================================================================
--- linux.orig/drivers/scsi/NCR5380.h 2015-12-06 12:30:27.000000000 +1100
+++ linux/drivers/scsi/NCR5380.h 2015-12-06 12:30:34.000000000 +1100
@@ -226,9 +226,7 @@
#define NO_IRQ 0
#endif

-#define FLAG_HAS_LAST_BYTE_SENT 1 /* NCR53c81 or better */
-#define FLAG_CHECK_LAST_BYTE_SENT 2 /* Only test once */
-#define FLAG_NCR53C400 4 /* NCR53c400 */
+#define FLAG_NO_DMA_FIXUP 1 /* No DMA errata workarounds */
#define FLAG_NO_PSEUDO_DMA 8 /* Inhibit DMA */
#define FLAG_DTC3181E 16 /* DTC3181E */
#define FLAG_LATE_DMA_SETUP 32 /* Setup NCR before DMA H/W */
Index: linux/drivers/scsi/dtc.c
===================================================================
--- linux.orig/drivers/scsi/dtc.c 2015-12-06 12:30:30.000000000 +1100
+++ linux/drivers/scsi/dtc.c 2015-12-06 12:30:34.000000000 +1100
@@ -1,7 +1,5 @@
#define PSEUDO_DMA
#define DONT_USE_INTR
-#define DMA_WORKS_RIGHT
-

/*
* DTC 3180/3280 driver, by
@@ -233,7 +231,7 @@ found:
instance->base = addr;
((struct NCR5380_hostdata *)(instance)->hostdata)->base = base;

- if (NCR5380_init(instance, 0))
+ if (NCR5380_init(instance, FLAG_NO_DMA_FIXUP))
goto out_unregister;

NCR5380_maybe_reset_bus(instance);
Index: linux/drivers/scsi/g_NCR5380.c
===================================================================
--- linux.orig/drivers/scsi/g_NCR5380.c 2015-12-06 12:30:30.000000000 +1100
+++ linux/drivers/scsi/g_NCR5380.c 2015-12-06 12:30:34.000000000 +1100
@@ -321,7 +321,7 @@ static int __init generic_NCR5380_detect
break;
case BOARD_NCR53C400:
#ifdef PSEUDO_DMA
- flags = FLAG_NCR53C400;
+ flags = FLAG_NO_DMA_FIXUP;
#endif
break;
case BOARD_NCR53C400A: