Re: [PATCH 0/4] g_NCR5380: PDMA fixes and cleanup
From: Finn Thain
Date: Fri Jun 23 2017 - 07:01:38 EST
On Fri, 23 Jun 2017, I wrote:
>
> Does this patch help? It should be applied on top of this series of 4.
>
Sorry, I sent the wrong diff. Please try this patch instead.
diff --git a/drivers/scsi/g_NCR5380.c b/drivers/scsi/g_NCR5380.c
index e9a942d86865..95ae8edbecbc 100644
--- a/drivers/scsi/g_NCR5380.c
+++ b/drivers/scsi/g_NCR5380.c
@@ -481,6 +481,30 @@ static void generic_NCR5380_release_resources(struct Scsi_Host *instance)
release_mem_region(base, region_size);
}
+/* wait_for_53c80_access - wait for 53C80 registers to become accessible
+ * @hostdata: scsi host private data
+ *
+ * The registers within the 53C80 logic block are inaccessible until
+ * bit 7 in the 53C400 control status register gets asserted.
+ */
+
+static int wait_for_53c80_access(struct NCR5380_hostdata *hostdata)
+{
+ int count = 10000;
+
+ do {
+ udelay(4); /* DTC436 chip hangs without this */
+ if (NCR5380_read(hostdata->c400_ctl_status) & CSR_53C80_REG)
+ return 0;
+ } while (--count > 0);
+
+ scmd_printk(KERN_ERR, hostdata->connected,
+ "53c80 registers not accessible, device will be reset\n");
+ NCR5380_write(hostdata->c400_ctl_status, CSR_RESET);
+ NCR5380_write(hostdata->c400_ctl_status, CSR_BASE);
+ return -1;
+}
+
/**
* generic_NCR5380_pread - pseudo DMA receive
* @hostdata: scsi host private data
@@ -493,18 +517,19 @@ static void generic_NCR5380_release_resources(struct Scsi_Host *instance)
static inline int generic_NCR5380_pread(struct NCR5380_hostdata *hostdata,
unsigned char *dst, int len)
{
- int blocks = len / 128;
- int start = 0;
+ int result;
+ int start;
NCR5380_write(hostdata->c400_ctl_status, CSR_BASE | CSR_TRANS_DIR);
- NCR5380_write(hostdata->c400_blk_cnt, blocks);
- while (1) {
- if (NCR5380_read(hostdata->c400_blk_cnt) == 0)
+ NCR5380_write(hostdata->c400_blk_cnt, len / 128);
+
+ for (start = 0; start < len; start += 128) {
+ if (NCR5380_poll_politely2(hostdata, hostdata->c400_ctl_status,
+ CSR_HOST_BUF_NOT_RDY, 0,
+ hostdata->c400_ctl_status,
+ CSR_GATED_53C80_IRQ,
+ CSR_GATED_53C80_IRQ, HZ / 64) < 0)
break;
- if (NCR5380_read(hostdata->c400_ctl_status) & CSR_GATED_53C80_IRQ)
- goto out_wait;
- while (NCR5380_read(hostdata->c400_ctl_status) & CSR_HOST_BUF_NOT_RDY)
- ; /* FIXME - no timeout */
if (hostdata->io_port && hostdata->io_width == 2)
insw(hostdata->io_port + hostdata->c400_host_buf,
@@ -515,43 +540,16 @@ static inline int generic_NCR5380_pread(struct NCR5380_hostdata *hostdata,
else
memcpy_fromio(dst + start,
hostdata->io + NCR53C400_host_buffer, 128);
-
- start += 128;
- blocks--;
- }
-
- if (blocks) {
- while (NCR5380_read(hostdata->c400_ctl_status) & CSR_HOST_BUF_NOT_RDY)
- ; /* FIXME - no timeout */
-
- if (hostdata->io_port && hostdata->io_width == 2)
- insw(hostdata->io_port + hostdata->c400_host_buf,
- dst + start, 64);
- else if (hostdata->io_port)
- insb(hostdata->io_port + hostdata->c400_host_buf,
- dst + start, 128);
- else
- memcpy_fromio(dst + start,
- hostdata->io + NCR53C400_host_buffer, 128);
-
- start += 128;
- blocks--;
}
- if (!(NCR5380_read(hostdata->c400_ctl_status) & CSR_GATED_53C80_IRQ))
- printk("53C400r: no 53C80 gated irq after transfer");
-
-out_wait:
- /* wait for 53C80 registers to be available */
- while (!(NCR5380_read(hostdata->c400_ctl_status) & CSR_53C80_REG))
- ;
+ result = wait_for_53c80_access(hostdata);
if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_END_DMA_TRANSFER))
pr_err("%s: No end dma signal (%d/%d)\n", __func__, start, len);
- hostdata->pdma_residual = len - start;
+ hostdata->pdma_residual = NCR5380_read(hostdata->c400_blk_cnt) * 128;
- return 0;
+ return result;
}
/**
@@ -566,36 +564,19 @@ static inline int generic_NCR5380_pread(struct NCR5380_hostdata *hostdata,
static inline int generic_NCR5380_pwrite(struct NCR5380_hostdata *hostdata,
unsigned char *src, int len)
{
- int blocks = len / 128;
- int start = 0;
+ int result;
+ int start;
NCR5380_write(hostdata->c400_ctl_status, CSR_BASE);
- NCR5380_write(hostdata->c400_blk_cnt, blocks);
- while (1) {
- if (NCR5380_read(hostdata->c400_ctl_status) & CSR_GATED_53C80_IRQ)
- goto out_wait;
-
- if (NCR5380_read(hostdata->c400_blk_cnt) == 0)
+ NCR5380_write(hostdata->c400_blk_cnt, len / 128);
+
+ for (start = 0; start < len; start += 128) {
+ if (NCR5380_poll_politely2(hostdata, hostdata->c400_ctl_status,
+ CSR_HOST_BUF_NOT_RDY, 0,
+ hostdata->c400_ctl_status,
+ CSR_GATED_53C80_IRQ,
+ CSR_GATED_53C80_IRQ, HZ / 64) < 0)
break;
- while (NCR5380_read(hostdata->c400_ctl_status) & CSR_HOST_BUF_NOT_RDY)
- ; // FIXME - timeout
-
- if (hostdata->io_port && hostdata->io_width == 2)
- outsw(hostdata->io_port + hostdata->c400_host_buf,
- src + start, 64);
- else if (hostdata->io_port)
- outsb(hostdata->io_port + hostdata->c400_host_buf,
- src + start, 128);
- else
- memcpy_toio(hostdata->io + NCR53C400_host_buffer,
- src + start, 128);
-
- start += 128;
- blocks--;
- }
- if (blocks) {
- while (NCR5380_read(hostdata->c400_ctl_status) & CSR_HOST_BUF_NOT_RDY)
- ; // FIXME - no timeout
if (hostdata->io_port && hostdata->io_width == 2)
outsw(hostdata->io_port + hostdata->c400_host_buf,
@@ -606,26 +587,23 @@ static inline int generic_NCR5380_pwrite(struct NCR5380_hostdata *hostdata,
else
memcpy_toio(hostdata->io + NCR53C400_host_buffer,
src + start, 128);
-
- start += 128;
- blocks--;
}
-out_wait:
- /* wait for 53C80 registers to be available */
- while (!(NCR5380_read(hostdata->c400_ctl_status) & CSR_53C80_REG)) {
- udelay(4); /* DTC436 chip hangs without this */
- /* FIXME - no timeout */
- }
+ result = wait_for_53c80_access(hostdata);
if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_END_DMA_TRANSFER))
pr_err("%s: No end dma signal (%d/%d)\n", __func__, start, len);
- hostdata->pdma_residual = len - start;
+ hostdata->pdma_residual = NCR5380_read(hostdata->c400_blk_cnt) * 128;
- while (!(NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT))
- ; // TIMEOUT
- return 0;
+ if (hostdata->pdma_residual == 0 &&
+ NCR5380_poll_politely(hostdata, TARGET_COMMAND_REG,
+ TCR_LAST_BYTE_SENT, TCR_LAST_BYTE_SENT,
+ HZ / 64) < 0)
+ scmd_printk(KERN_ERR, hostdata->connected,
+ "%s: Last Byte Sent timeout\n", __func__);
+
+ return result;
}
static int generic_NCR5380_dma_xfer_len(struct NCR5380_hostdata *hostdata,