[PATCH 15/44] leon, grspw_pkt: fixed and improved RX/TX wait
Daniel Hellstrom
daniel at gaisler.com
Fri Mar 3 14:56:48 UTC 2017
---
c/src/lib/libbsp/sparc/shared/include/grspw_pkt.h | 6 +-
c/src/lib/libbsp/sparc/shared/spw/grspw_pkt.c | 99 +++++++++++++----------
2 files changed, 61 insertions(+), 44 deletions(-)
diff --git a/c/src/lib/libbsp/sparc/shared/include/grspw_pkt.h b/c/src/lib/libbsp/sparc/shared/include/grspw_pkt.h
index 17bbee8..0bc749f 100644
--- a/c/src/lib/libbsp/sparc/shared/include/grspw_pkt.h
+++ b/c/src/lib/libbsp/sparc/shared/include/grspw_pkt.h
@@ -487,7 +487,7 @@ extern void grspw_dma_tx_count(void *c, int *send, int *sched, int *sent);
#define GRSPW_OP_AND 0
#define GRSPW_OP_OR 1
-/* Block until ready_cnt or fewer packets are Queued in "Send and Scheduled" Q,
+/* Block until send_cnt or fewer packets are Queued in "Send and Scheduled" Q,
* op (AND or OR), sent_cnt or more packet "have been sent" (Sent Q) condition
* is met.
* If a link error occurs and the Stop on Link error is defined, this function
@@ -504,6 +504,7 @@ extern void grspw_dma_tx_count(void *c, int *send, int *sched, int *sent);
* 0 Returing to caller because specified conditions are now fullfilled
* 1 DMA stopped
* 2 Timeout, conditions are not met
+ * 3 Another task is already waiting. Service is Busy.
*/
extern int grspw_dma_tx_wait(void *c, int send_cnt, int op, int sent_cnt, int timeout);
@@ -565,7 +566,7 @@ extern void grspw_dma_rx_count(void *c, int *ready, int *sched, int *recv);
* the other conditions. If timeout is zero, the function will wait forever
* until the condition is satisfied.
*
- * NOTE: if IRQ of TX descriptors are not enabled conditions are never
+ * NOTE: if IRQ of RX descriptors are not enabled conditions are never
* checked, this may hang infinitely unless a timeout has been specified
*
* Return Code
@@ -573,6 +574,7 @@ extern void grspw_dma_rx_count(void *c, int *ready, int *sched, int *recv);
* 0 Returing to caller because specified conditions are now fullfilled
* 1 DMA stopped
* 2 Timeout, conditions are not met
+ * 3 Another task is already waiting. Service is Busy.
*/
extern int grspw_dma_rx_wait(void *c, int recv_cnt, int op, int ready_cnt, int timeout);
diff --git a/c/src/lib/libbsp/sparc/shared/spw/grspw_pkt.c b/c/src/lib/libbsp/sparc/shared/spw/grspw_pkt.c
index ce4012b..359b1ac 100644
--- a/c/src/lib/libbsp/sparc/shared/spw/grspw_pkt.c
+++ b/c/src/lib/libbsp/sparc/shared/spw/grspw_pkt.c
@@ -1926,7 +1926,7 @@ static inline int grspw_tx_wait_eval(struct grspw_dma_priv *dma)
int grspw_dma_tx_wait(void *c, int send_cnt, int op, int sent_cnt, int timeout)
{
struct grspw_dma_priv *dma = c;
- int ret, rc;
+ int ret, rc, initialized = 0;
if (timeout == 0)
timeout = RTEMS_NO_TIMEOUT;
@@ -1941,15 +1941,15 @@ check_condition:
/* Check so that no other thread is waiting, this driver only supports
* one waiter at a time.
*/
- if (dma->tx_wait.waiting) {
- ret = -1;
- goto out;
+ if (initialized == 0 && dma->tx_wait.waiting) {
+ ret = 3;
+ goto out_release;
}
- /* Stop if link error or similar, abort */
+ /* Stop if link error or similar (DMA stopped), abort */
if (dma->started == 0) {
ret = 1;
- goto out;
+ goto out_release;
}
/* Set up Condition */
@@ -1959,6 +1959,7 @@ check_condition:
if (grspw_tx_wait_eval(dma) == 0) {
/* Prepare Wait */
+ initialized = 1;
dma->tx_wait.waiting = 1;
/* Release DMA channel lock */
@@ -1970,27 +1971,34 @@ check_condition:
rc = rtems_semaphore_obtain(dma->tx_wait.sem_wait, RTEMS_WAIT,
timeout);
if (rc == RTEMS_TIMEOUT) {
- dma->tx_wait.waiting = 0;
- return 2;
+ ret = 2;
+ goto out;
} else if (rc == RTEMS_UNSATISFIED ||
rc == RTEMS_OBJECT_WAS_DELETED) {
- dma->tx_wait.waiting = 0;
- return 1; /* sem was flushed/deleted, means DMA stop */
- } else if (rc != RTEMS_SUCCESSFUL)
- return -1;
+ ret = 1; /* sem was flushed/deleted, means DMA stop */
+ goto out;
+ } else if (rc != RTEMS_SUCCESSFUL) {
+ /* Unknown Error */
+ ret = -1;
+ goto out;
+ } else if (dma->started == 0) {
+ ret = 1;
+ goto out;
+ }
/* Check condition once more */
goto check_condition;
- } else {
- /* No Wait needed */
- dma->tx_wait.waiting = 0;
}
ret = 0;
-out:
+
+out_release:
/* Unlock DMA channel */
rtems_semaphore_release(dma->sem_dma);
+out:
+ if (initialized)
+ dma->tx_wait.waiting = 0;
return ret;
}
@@ -2132,7 +2140,7 @@ static inline int grspw_rx_wait_eval(struct grspw_dma_priv *dma)
int grspw_dma_rx_wait(void *c, int recv_cnt, int op, int ready_cnt, int timeout)
{
struct grspw_dma_priv *dma = c;
- int ret, rc;
+ int ret, rc, initialized = 0;
if (timeout == 0)
timeout = RTEMS_NO_TIMEOUT;
@@ -2147,15 +2155,15 @@ check_condition:
/* Check so that no other thread is waiting, this driver only supports
* one waiter at a time.
*/
- if (dma->rx_wait.waiting) {
- ret = -1;
- goto out;
+ if (initialized == 0 && dma->rx_wait.waiting) {
+ ret = 3;
+ goto out_release;
}
- /* Stop if link error or similar (MDA stopped) */
+ /* Stop if link error or similar (DMA stopped), abort */
if (dma->started == 0) {
ret = 1;
- goto out;
+ goto out_release;
}
/* Set up Condition */
@@ -2165,6 +2173,7 @@ check_condition:
if (grspw_rx_wait_eval(dma) == 0) {
/* Prepare Wait */
+ initialized = 1;
dma->rx_wait.waiting = 1;
/* Release channel lock */
@@ -2176,27 +2185,34 @@ check_condition:
rc = rtems_semaphore_obtain(dma->rx_wait.sem_wait, RTEMS_WAIT,
timeout);
if (rc == RTEMS_TIMEOUT) {
- dma->rx_wait.waiting = 0;
- return 2;
+ ret = 2;
+ goto out;
} else if (rc == RTEMS_UNSATISFIED ||
rc == RTEMS_OBJECT_WAS_DELETED) {
- dma->rx_wait.waiting = 0;
- return 1; /* sem was flushed/deleted, means DMA stop */
- } else if (rc != RTEMS_SUCCESSFUL)
- return -1;
+ ret = 1; /* sem was flushed/deleted, means DMA stop */
+ goto out;
+ } else if (rc != RTEMS_SUCCESSFUL) {
+ /* Unknown Error */
+ ret = -1;
+ goto out;
+ } else if (dma->started == 0) {
+ ret = 1;
+ goto out;
+ }
/* Check condition once more */
goto check_condition;
- } else {
- /* No Wait needed */
- dma->rx_wait.waiting = 0;
}
+
ret = 0;
-out:
+out_release:
/* Unlock DMA channel */
rtems_semaphore_release(dma->sem_dma);
+out:
+ if (initialized)
+ dma->rx_wait.waiting = 0;
return ret;
}
@@ -2398,8 +2414,8 @@ static void grspw_work_shutdown_func(struct grspw_priv *priv)
int i;
/* Link is down for some reason, and the user has configured
- * that we stop all DMA channels and throw out all blocked
- * threads.
+ * that we stop all (open) DMA channels and throw out all their
+ * blocked threads.
*/
for (i=0; i<priv->hwsup.ndma_chans; i++)
grspw_dma_stop(&priv->dma[i]);
@@ -2422,6 +2438,10 @@ static void grspw_work_dma_func(struct grspw_dma_priv *dma)
!= RTEMS_SUCCESSFUL)
return;
+ /* If closing DMA channel or just shut down */
+ if (dma->started == 0)
+ goto out;
+
/* Look at cause we were woken up and clear source */
SPIN_LOCK_IRQ(&priv->devlock, irqflags);
ctrl = REG_READ(&dma->regs->ctrl);
@@ -2448,26 +2468,21 @@ static void grspw_work_dma_func(struct grspw_dma_priv *dma)
/* Check to see if condition for waking blocked USER
* task is fullfilled.
*/
- if (dma->rx_wait.waiting) {
+ if (dma->rx_wait.waiting)
rx_cond_true = grspw_rx_wait_eval(dma);
- if (rx_cond_true)
- dma->rx_wait.waiting = 0;
- }
}
if (ctrl & GRSPW_DMACTRL_PS) {
/* Do TX Work */
dma->stats.tx_work_cnt++;
grspw_tx_process_scheduled(dma);
dma->stats.tx_work_enabled += grspw_tx_schedule_send(dma);
- if (dma->tx_wait.waiting) {
+ if (dma->tx_wait.waiting)
tx_cond_true = grspw_tx_wait_eval(dma);
- if (tx_cond_true)
- dma->tx_wait.waiting = 0;
- }
}
} else
SPIN_UNLOCK_IRQ(&priv->devlock, irqflags);
+out:
/* Release lock */
rtems_semaphore_release(dma->sem_dma);
--
2.7.4
More information about the devel
mailing list