Before the error handling can be revised, some preparation is needed.
Refactor the polling loop with a new function, macscsi_wait_for_drq().
This function will gain more call sites in the next patch.
Cc: stable@xxxxxxxxxxxxxxx # 5.15+
Tested-by: Stan Johnson <userm57@xxxxxxxxx>
Signed-off-by: Finn Thain <fthain@xxxxxxxxxxxxxx>
---
This is not really a bug fix, but has been sent to @stable because it is a
prerequisite for the bug fixes which follow.
---
drivers/scsi/mac_scsi.c | 80 +++++++++++++++++++++--------------------
1 file changed, 42 insertions(+), 38 deletions(-)
diff --git a/drivers/scsi/mac_scsi.c b/drivers/scsi/mac_scsi.c
index 5ae8f4a1e9ca..39814c841113 100644
--- a/drivers/scsi/mac_scsi.c
+++ b/drivers/scsi/mac_scsi.c
@@ -208,8 +208,6 @@ __setup("mac5380=", mac_scsi_setup);
".previous \n" \
: "+a" (addr), "+r" (n), "+r" (result) : "a" (io))
-#define MAC_PDMA_DELAY 32
-
static inline int mac_pdma_recv(void __iomem *io, unsigned char *start, int n)
{
unsigned char *addr = start;
@@ -274,6 +272,36 @@ static inline void write_ctrl_reg(struct NCR5380_hostdata *hostdata, u32 value)
out_be32(hostdata->io + (CTRL_REG << 4), value);
}
+static inline int macscsi_wait_for_drq(struct NCR5380_hostdata *hostdata)
+{
+ unsigned int n = 1; /* effectively multiplies NCR5380_REG_POLL_TIME */
+ unsigned char basr;
+
+again:
+ basr = NCR5380_read(BUS_AND_STATUS_REG);
+
+ if (!(basr & BASR_PHASE_MATCH))
+ return 1;
+
+ if (basr & BASR_IRQ)
+ return -1;
+
+ if (basr & BASR_DRQ)
+ return 0;
+
+ if (n-- == 0) {
+ NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
+ dsprintk(NDEBUG_PSEUDO_DMA, hostdata->host,
+ "%s: DRQ timeout\n", __func__);
+ return -1;
+ }
+
+ NCR5380_poll_politely2(hostdata,
+ BUS_AND_STATUS_REG, BASR_DRQ, BASR_DRQ,
+ BUS_AND_STATUS_REG, BASR_PHASE_MATCH, 0, 0);
+ goto again;
+}
+
static inline int macscsi_pread(struct NCR5380_hostdata *hostdata,
unsigned char *dst, int len)
{
@@ -283,9 +311,7 @@ static inline int macscsi_pread(struct NCR5380_hostdata *hostdata,
hostdata->pdma_residual = len;
- while (!NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
- BASR_DRQ | BASR_PHASE_MATCH,
- BASR_DRQ | BASR_PHASE_MATCH, 0)) {
+ while (macscsi_wait_for_drq(hostdata) == 0) {
int bytes, chunk_bytes;
if (macintosh_config->ident == MAC_MODEL_IIFX)
@@ -295,19 +321,16 @@ static inline int macscsi_pread(struct NCR5380_hostdata *hostdata,
chunk_bytes = min(hostdata->pdma_residual, 512);
bytes = mac_pdma_recv(s, d, chunk_bytes);
+ if (macintosh_config->ident == MAC_MODEL_IIFX)
+ write_ctrl_reg(hostdata, CTRL_INTERRUPTS_ENABLE);
+
if (bytes > 0) {
d += bytes;
hostdata->pdma_residual -= bytes;
}
if (hostdata->pdma_residual == 0)
- goto out;
-
- if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH))
- goto out;
-
- if (bytes == 0)
- udelay(MAC_PDMA_DELAY);
+ break;
if (bytes > 0)
continue;
@@ -321,16 +344,9 @@ static inline int macscsi_pread(struct NCR5380_hostdata *hostdata,
continue;
result = -1;
- goto out;
+ break;
}
- scmd_printk(KERN_ERR, hostdata->connected,
- "%s: phase mismatch or !DRQ\n", __func__);
- NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
- result = -1;
-out:
- if (macintosh_config->ident == MAC_MODEL_IIFX)
- write_ctrl_reg(hostdata, CTRL_INTERRUPTS_ENABLE);
return result;
}
@@ -343,9 +359,7 @@ static inline int macscsi_pwrite(struct NCR5380_hostdata *hostdata,
hostdata->pdma_residual = len;
- while (!NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
- BASR_DRQ | BASR_PHASE_MATCH,
- BASR_DRQ | BASR_PHASE_MATCH, 0)) {
+ while (macscsi_wait_for_drq(hostdata) == 0) {
int bytes, chunk_bytes;
if (macintosh_config->ident == MAC_MODEL_IIFX)
@@ -355,6 +369,9 @@ static inline int macscsi_pwrite(struct NCR5380_hostdata *hostdata,
chunk_bytes = min(hostdata->pdma_residual, 512);
bytes = mac_pdma_send(s, d, chunk_bytes);
+ if (macintosh_config->ident == MAC_MODEL_IIFX)
+ write_ctrl_reg(hostdata, CTRL_INTERRUPTS_ENABLE);
+
if (bytes > 0) {
s += bytes;
hostdata->pdma_residual -= bytes;
@@ -369,15 +386,9 @@ static inline int macscsi_pwrite(struct NCR5380_hostdata *hostdata,
"%s: Last Byte Sent timeout\n", __func__);
result = -1;
}
- goto out;
+ break;
}
- if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH))
- goto out;
-
- if (bytes == 0)
- udelay(MAC_PDMA_DELAY);
-
if (bytes > 0)
continue;
@@ -390,16 +401,9 @@ static inline int macscsi_pwrite(struct NCR5380_hostdata *hostdata,
continue;
result = -1;
- goto out;
+ break;
}
- scmd_printk(KERN_ERR, hostdata->connected,
- "%s: phase mismatch or !DRQ\n", __func__);
- NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
- result = -1;
-out:
- if (macintosh_config->ident == MAC_MODEL_IIFX)
- write_ctrl_reg(hostdata, CTRL_INTERRUPTS_ENABLE);
return result;
}
--
2.39.5
