Re: [PATCH v3 40/77] ncr5380: Introduce NCR5380_poll_politely2

2015-12-21 Thread Hannes Reinecke 

On 12/22/2015 02:18 AM, Finn Thain wrote:

SCSI bus protocol sometimes requires monitoring two related conditions
simultaneously. Enhance NCR5380_poll_politely() for this purpose, and
put it to use in the arbitration algorithm. It will also find use in
pseudo DMA.

Signed-off-by: Finn Thain 

---
  drivers/scsi/NCR5380.c   |   66 
---
  drivers/scsi/atari_NCR5380.c |   62 
  2 files changed, 75 insertions(+), 53 deletions(-)


Reviewed-by: Hannes Reinecke 

Cheers,

Hannes
--
Dr. Hannes Reinecke   zSeries & Storage
h...@suse.de  +49 911 74053 688
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg
GF: J. Hawn, J. Guild, F. Imendörffer, HRB 16746 (AG Nürnberg)
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[PATCH v3 40/77] ncr5380: Introduce NCR5380_poll_politely2

2015-12-21 Thread Finn Thain 
SCSI bus protocol sometimes requires monitoring two related conditions
simultaneously. Enhance NCR5380_poll_politely() for this purpose, and
put it to use in the arbitration algorithm. It will also find use in
pseudo DMA.

Signed-off-by: Finn Thain 

---
 drivers/scsi/NCR5380.c   |   66 ---
 drivers/scsi/atari_NCR5380.c |   62 
 2 files changed, 75 insertions(+), 53 deletions(-)

Index: linux/drivers/scsi/atari_NCR5380.c
===
--- linux.orig/drivers/scsi/atari_NCR5380.c 2015-12-22 12:16:28.0 
+1100
+++ linux/drivers/scsi/atari_NCR5380.c  2015-12-22 12:16:30.0 +1100
@@ -457,11 +457,14 @@ static inline void initialize_SCp(struct
 }
 
 /**
- * NCR5380_poll_politely - wait for chip register value
+ * NCR5380_poll_politely2 - wait for two chip register values
  * @instance: controller to poll
- * @reg: 5380 register to poll
- * @bit: Bitmask to check
- * @val: Value required to exit
+ * @reg1: 5380 register to poll
+ * @bit1: Bitmask to check
+ * @val1: Expected value
+ * @reg2: Second 5380 register to poll
+ * @bit2: Second bitmask to check
+ * @val2: Second expected value
  * @wait: Time-out in jiffies
  *
  * Polls the chip in a reasonably efficient manner waiting for an
@@ -469,11 +472,12 @@ static inline void initialize_SCp(struct
  * (if possible). In irq contexts the time-out is arbitrarily limited.
  * Callers may hold locks as long as they are held in irq mode.
  *
- * Returns 0 if event occurred otherwise -ETIMEDOUT.
+ * Returns 0 if either or both event(s) occurred otherwise -ETIMEDOUT.
  */
 
-static int NCR5380_poll_politely(struct Scsi_Host *instance,
- int reg, int bit, int val, int wait)
+static int NCR5380_poll_politely2(struct Scsi_Host *instance,
+  int reg1, int bit1, int val1,
+  int reg2, int bit2, int val2, int wait)
 {
struct NCR5380_hostdata *hostdata = shost_priv(instance);
unsigned long deadline = jiffies + wait;
@@ -482,9 +486,11 @@ static int NCR5380_poll_politely(struct
/* Busy-wait for up to 10 ms */
n = min(1U, jiffies_to_usecs(wait));
n *= hostdata->accesses_per_ms;
-   n /= 1000;
+   n /= 2000;
do {
-   if ((NCR5380_read(reg) & bit) == val)
+   if ((NCR5380_read(reg1) & bit1) == val1)
+   return 0;
+   if ((NCR5380_read(reg2) & bit2) == val2)
return 0;
cpu_relax();
} while (n--);
@@ -495,13 +501,22 @@ static int NCR5380_poll_politely(struct
/* Repeatedly sleep for 1 ms until deadline */
while (time_is_after_jiffies(deadline)) {
schedule_timeout_uninterruptible(1);
-   if ((NCR5380_read(reg) & bit) == val)
+   if ((NCR5380_read(reg1) & bit1) == val1)
+   return 0;
+   if ((NCR5380_read(reg2) & bit2) == val2)
return 0;
}
 
return -ETIMEDOUT;
 }
 
+static inline int NCR5380_poll_politely(struct Scsi_Host *instance,
+int reg, int bit, int val, int wait)
+{
+   return NCR5380_poll_politely2(instance, reg, bit, val,
+   reg, bit, val, wait);
+}
+
 #include 
 
 #if NDEBUG
@@ -1348,7 +1363,6 @@ static int NCR5380_select(struct Scsi_Ho
int len;
int err;
unsigned long flags;
-   unsigned long timeout;
 
NCR5380_dprint(NDEBUG_ARBITRATION, instance);
dprintk(NDEBUG_ARBITRATION, "scsi%d: starting arbitration, id = %d\n", 
HOSTNO,
@@ -1378,20 +1392,18 @@ static int NCR5380_select(struct Scsi_Ho
 */
 
local_irq_restore(flags);
-   timeout = jiffies + HZ;
-   while (1) {
-   if (time_is_before_jiffies(timeout)) {
-   NCR5380_write(MODE_REG, MR_BASE);
-   shost_printk(KERN_ERR, instance,
-"select: arbitration timeout\n");
-   return -1;
-   }
-   if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) {
-   /* Reselection interrupt */
-   return -1;
-   }
-   if (NCR5380_read(INITIATOR_COMMAND_REG) & 
ICR_ARBITRATION_PROGRESS)
-   break;
+   err = NCR5380_poll_politely2(instance, MODE_REG, MR_ARBITRATE, 0,
+   INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS,
+  ICR_ARBITRATION_PROGRESS, HZ);
+   if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) {
+   /* Reselection interrupt */
+   return -1;
+   }
+   if (err < 0) {
+   NCR5380_write(MODE_REG, MR_BASE);
+

[PATCH v3 40/77] ncr5380: Introduce NCR5380_poll_politely2

2015-12-21 Thread Finn Thain 
SCSI bus protocol sometimes requires monitoring two related conditions
simultaneously. Enhance NCR5380_poll_politely() for this purpose, and
put it to use in the arbitration algorithm. It will also find use in
pseudo DMA.

Signed-off-by: Finn Thain 

---
 drivers/scsi/NCR5380.c   |   66 ---
 drivers/scsi/atari_NCR5380.c |   62 
 2 files changed, 75 insertions(+), 53 deletions(-)

Index: linux/drivers/scsi/atari_NCR5380.c
===
--- linux.orig/drivers/scsi/atari_NCR5380.c 2015-12-22 12:16:28.0 
+1100
+++ linux/drivers/scsi/atari_NCR5380.c  2015-12-22 12:16:30.0 +1100
@@ -457,11 +457,14 @@ static inline void initialize_SCp(struct
 }
 
 /**
- * NCR5380_poll_politely - wait for chip register value
+ * NCR5380_poll_politely2 - wait for two chip register values
  * @instance: controller to poll
- * @reg: 5380 register to poll
- * @bit: Bitmask to check
- * @val: Value required to exit
+ * @reg1: 5380 register to poll
+ * @bit1: Bitmask to check
+ * @val1: Expected value
+ * @reg2: Second 5380 register to poll
+ * @bit2: Second bitmask to check
+ * @val2: Second expected value
  * @wait: Time-out in jiffies
  *
  * Polls the chip in a reasonably efficient manner waiting for an
@@ -469,11 +472,12 @@ static inline void initialize_SCp(struct
  * (if possible). In irq contexts the time-out is arbitrarily limited.
  * Callers may hold locks as long as they are held in irq mode.
  *
- * Returns 0 if event occurred otherwise -ETIMEDOUT.
+ * Returns 0 if either or both event(s) occurred otherwise -ETIMEDOUT.
  */
 
-static int NCR5380_poll_politely(struct Scsi_Host *instance,
- int reg, int bit, int val, int wait)
+static int NCR5380_poll_politely2(struct Scsi_Host *instance,
+  int reg1, int bit1, int val1,
+  int reg2, int bit2, int val2, int wait)
 {
struct NCR5380_hostdata *hostdata = shost_priv(instance);
unsigned long deadline = jiffies + wait;
@@ -482,9 +486,11 @@ static int NCR5380_poll_politely(struct
/* Busy-wait for up to 10 ms */
n = min(1U, jiffies_to_usecs(wait));
n *= hostdata->accesses_per_ms;
-   n /= 1000;
+   n /= 2000;
do {
-   if ((NCR5380_read(reg) & bit) == val)
+   if ((NCR5380_read(reg1) & bit1) == val1)
+   return 0;
+   if ((NCR5380_read(reg2) & bit2) == val2)
return 0;
cpu_relax();
} while (n--);
@@ -495,13 +501,22 @@ static int NCR5380_poll_politely(struct
/* Repeatedly sleep for 1 ms until deadline */
while (time_is_after_jiffies(deadline)) {
schedule_timeout_uninterruptible(1);
-   if ((NCR5380_read(reg) & bit) == val)
+   if ((NCR5380_read(reg1) & bit1) == val1)
+   return 0;
+   if ((NCR5380_read(reg2) & bit2) == val2)
return 0;
}
 
return -ETIMEDOUT;
 }
 
+static inline int NCR5380_poll_politely(struct Scsi_Host *instance,
+int reg, int bit, int val, int wait)
+{
+   return NCR5380_poll_politely2(instance, reg, bit, val,
+   reg, bit, val, wait);
+}
+
 #include 
 
 #if NDEBUG
@@ -1348,7 +1363,6 @@ static int NCR5380_select(struct Scsi_Ho
int len;
int err;
unsigned long flags;
-   unsigned long timeout;
 
NCR5380_dprint(NDEBUG_ARBITRATION, instance);
dprintk(NDEBUG_ARBITRATION, "scsi%d: starting arbitration, id = %d\n", 
HOSTNO,
@@ -1378,20 +1392,18 @@ static int NCR5380_select(struct Scsi_Ho
 */
 
local_irq_restore(flags);
-   timeout = jiffies + HZ;
-   while (1) {
-   if (time_is_before_jiffies(timeout)) {
-   NCR5380_write(MODE_REG, MR_BASE);
-   shost_printk(KERN_ERR, instance,
-"select: arbitration timeout\n");
-   return -1;
-   }
-   if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) {
-   /* Reselection interrupt */
-   return -1;
-   }
-   if (NCR5380_read(INITIATOR_COMMAND_REG) & 
ICR_ARBITRATION_PROGRESS)
-   break;
+   err = NCR5380_poll_politely2(instance, MODE_REG, MR_ARBITRATE, 0,
+   INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS,
+  ICR_ARBITRATION_PROGRESS, HZ);
+   if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) {
+   /* Reselection interrupt */
+   return -1;
+   }
+   if (err < 0) {
+   NCR5380_write(MODE_REG, MR_BASE);
+

Re: [PATCH v3 40/77] ncr5380: Introduce NCR5380_poll_politely2

2015-12-21 Thread Hannes Reinecke 

On 12/22/2015 02:18 AM, Finn Thain wrote:

SCSI bus protocol sometimes requires monitoring two related conditions
simultaneously. Enhance NCR5380_poll_politely() for this purpose, and
put it to use in the arbitration algorithm. It will also find use in
pseudo DMA.

Signed-off-by: Finn Thain 

---
  drivers/scsi/NCR5380.c   |   66 
---
  drivers/scsi/atari_NCR5380.c |   62 
  2 files changed, 75 insertions(+), 53 deletions(-)


Reviewed-by: Hannes Reinecke 

Cheers,

Hannes
--
Dr. Hannes Reinecke   zSeries & Storage
h...@suse.de  +49 911 74053 688
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg
GF: J. Hawn, J. Guild, F. Imendörffer, HRB 16746 (AG Nürnberg)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/