scsi: mac_scsi: Refactor polling loop

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@vger.kernel.org # 5.15+
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@linux-m68k.org>
Link: https://lore.kernel.org/r/6a5ffabb4290c0d138c6d285fda8fa3902e926f0.1723001788.git.fthain@linux-m68k.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Finn Thain 2024-08-07 13:36:28 +10:00 committed by Martin K. Petersen
parent 5ec4f820cb
commit 5545c3165c

View File

@ -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;
}