By introducing a spearate RX and TX DMA channel semaphore RX
operations and TX operations does not block each other. Stopping
a DMA channel needs now to take both RX and TX semaphores to
block out both RX and TX tasks.
---
c/src/lib/libbsp/sparc/shared/spw/grspw_pkt.c | 148 ++++++++++++++++----------
1 file changed, 94 insertions(+), 54 deletions(-)
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 ddde100..60aa68f 100644
--- a/c/src/lib/libbsp/sparc/shared/spw/grspw_pkt.c
+++ b/c/src/lib/libbsp/sparc/shared/spw/grspw_pkt.c
@@ -376,7 +376,8 @@ struct grspw_dma_priv {
int index; /* DMA Channel Index @ GRSPW core */
int open; /* DMA Channel opened by user */
int started; /* DMA Channel activity (start|stop) */
- rtems_id sem_dma; /* DMA Channel Semaphore */
+ rtems_id sem_rxdma; /* DMA Channel RX Semaphore */
+ rtems_id sem_txdma; /* DMA Channel TX Semaphore */
struct grspw_dma_stats stats; /* DMA Channel Statistics */
struct grspw_dma_config cfg; /* DMA Channel Configuration */
@@ -1657,18 +1658,27 @@ void *grspw_dma_open(void *d, int chan_no)
dma->cfg.flags = DMAFLAG_NO_SPILL;
/* set to NULL so that error exit works correctly */
- dma->sem_dma = RTEMS_ID_NONE;
+ dma->sem_rxdma = RTEMS_ID_NONE;
+ dma->sem_txdma = RTEMS_ID_NONE;
dma->rx_wait.sem_wait = RTEMS_ID_NONE;
dma->tx_wait.sem_wait = RTEMS_ID_NONE;
dma->rx_ring_base = NULL;
/* DMA Channel Semaphore created with count = 1 */
if (rtems_semaphore_create(
- rtems_build_name('S', 'D', '0' + priv->index, '0' + chan_no), 1,
+ rtems_build_name('S', 'D', '0' + priv->index, '0' + chan_no*2), 1,
RTEMS_FIFO | RTEMS_SIMPLE_BINARY_SEMAPHORE | \
RTEMS_NO_INHERIT_PRIORITY | RTEMS_LOCAL | \
- RTEMS_NO_PRIORITY_CEILING, 0, &dma->sem_dma) != RTEMS_SUCCESSFUL) {
- dma->sem_dma = RTEMS_ID_NONE;
+ RTEMS_NO_PRIORITY_CEILING, 0, &dma->sem_rxdma) != RTEMS_SUCCESSFUL)
{
+ dma->sem_rxdma = RTEMS_ID_NONE;
+ goto err;
+ }
+ if (rtems_semaphore_create(
+ rtems_build_name('S', 'D', '0' + priv->index, '0' + chan_no*2+1), 1,
+ RTEMS_FIFO | RTEMS_SIMPLE_BINARY_SEMAPHORE | \
+ RTEMS_NO_INHERIT_PRIORITY | RTEMS_LOCAL | \
+ RTEMS_NO_PRIORITY_CEILING, 0, &dma->sem_txdma) != RTEMS_SUCCESSFUL)
{
+ dma->sem_txdma = RTEMS_ID_NONE;
goto err;
}
@@ -1710,8 +1720,10 @@ out:
/* initialization error happended */
err:
- if (dma->sem_dma != RTEMS_ID_NONE)
- rtems_semaphore_delete(dma->sem_dma);
+ if (dma->sem_rxdma != RTEMS_ID_NONE)
+ rtems_semaphore_delete(dma->sem_rxdma);
+ if (dma->sem_txdma != RTEMS_ID_NONE)
+ rtems_semaphore_delete(dma->sem_txdma);
if (dma->rx_wait.sem_wait != RTEMS_ID_NONE)
rtems_semaphore_delete(dma->rx_wait.sem_wait);
if (dma->tx_wait.sem_wait != RTEMS_ID_NONE)
@@ -1764,15 +1776,21 @@ int grspw_dma_close(void *c)
return 0;
/* Take device lock - Wait until we get semaphore */
- if (rtems_semaphore_obtain(dma->sem_dma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
+ if (rtems_semaphore_obtain(dma->sem_rxdma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
!= RTEMS_SUCCESSFUL)
return -1;
+ if (rtems_semaphore_obtain(dma->sem_txdma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
+ != RTEMS_SUCCESSFUL) {
+ rtems_semaphore_release(dma->sem_rxdma);
+ return -1;
+ }
/* Can not close active DMA channel. User must stop DMA and make sure
* no threads are active/blocked within driver.
*/
if (dma->started || dma->rx_wait.waiting || dma->tx_wait.waiting) {
- rtems_semaphore_release(dma->sem_dma);
+ rtems_semaphore_release(dma->sem_txdma);
+ rtems_semaphore_release(dma->sem_rxdma);
return 1;
}
@@ -1780,8 +1798,10 @@ int grspw_dma_close(void *c)
rtems_semaphore_delete(dma->rx_wait.sem_wait);
rtems_semaphore_delete(dma->tx_wait.sem_wait);
/* Release and delete lock. Operations requiring lock will fail */
- rtems_semaphore_delete(dma->sem_dma);
- dma->sem_dma = RTEMS_ID_NONE;
+ rtems_semaphore_delete(dma->sem_txdma);
+ rtems_semaphore_delete(dma->sem_rxdma);
+ dma->sem_txdma = RTEMS_ID_NONE;
+ dma->sem_rxdma = RTEMS_ID_NONE;
/* Free memory */
if (dma->rx_ring_base)
@@ -1806,7 +1826,7 @@ int grspw_dma_tx_send(void *c, int opts, struct
grspw_list *pkts, int count)
int ret;
/* Take DMA channel lock */
- if (rtems_semaphore_obtain(dma->sem_dma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
+ if (rtems_semaphore_obtain(dma->sem_txdma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
!= RTEMS_SUCCESSFUL)
return -1;
@@ -1834,7 +1854,7 @@ int grspw_dma_tx_send(void *c, int opts, struct
grspw_list *pkts, int count)
out:
/* Unlock DMA channel */
- rtems_semaphore_release(dma->sem_dma);
+ rtems_semaphore_release(dma->sem_txdma);
return ret;
}
@@ -1846,7 +1866,7 @@ int grspw_dma_tx_reclaim(void *c, int opts, struct
grspw_list *pkts, int *count)
int cnt, started;
/* Take DMA channel lock */
- if (rtems_semaphore_obtain(dma->sem_dma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
+ if (rtems_semaphore_obtain(dma->sem_txdma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
!= RTEMS_SUCCESSFUL)
return -1;
@@ -1891,7 +1911,7 @@ int grspw_dma_tx_reclaim(void *c, int opts, struct
grspw_list *pkts, int *count)
grspw_tx_schedule_send(dma);
/* Unlock DMA channel */
- rtems_semaphore_release(dma->sem_dma);
+ rtems_semaphore_release(dma->sem_txdma);
return (~started) & 1; /* signal DMA has been stopped */
}
@@ -1908,7 +1928,7 @@ void grspw_dma_tx_count(void *c, int *send, int *sched,
int *sent, int *hw)
* and that DMA descriptor table and tx_ring_tail is not being updated
* during HW counter processing in this function.
*/
- if (rtems_semaphore_obtain(dma->sem_dma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
+ if (rtems_semaphore_obtain(dma->sem_txdma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
!= RTEMS_SUCCESSFUL)
return;
@@ -1938,7 +1958,7 @@ void grspw_dma_tx_count(void *c, int *send, int *sched,
int *sent, int *hw)
}
/* Unlock DMA channel */
- rtems_semaphore_release(dma->sem_dma);
+ rtems_semaphore_release(dma->sem_txdma);
}
static inline int grspw_tx_wait_eval(struct grspw_dma_priv *dma)
@@ -1979,7 +1999,7 @@ int grspw_dma_tx_wait(void *c, int send_cnt, int op, int
sent_cnt, int timeout)
check_condition:
/* Take DMA channel lock */
- if (rtems_semaphore_obtain(dma->sem_dma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
+ if (rtems_semaphore_obtain(dma->sem_txdma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
!= RTEMS_SUCCESSFUL)
return -1;
@@ -2008,7 +2028,7 @@ check_condition:
dma->tx_wait.waiting = 1;
/* Release DMA channel lock */
- rtems_semaphore_release(dma->sem_dma);
+ rtems_semaphore_release(dma->sem_txdma);
/* Try to take Wait lock, if this fail link may have gone down
* or user stopped this DMA channel
@@ -2039,7 +2059,7 @@ check_condition:
out_release:
/* Unlock DMA channel */
- rtems_semaphore_release(dma->sem_dma);
+ rtems_semaphore_release(dma->sem_txdma);
out:
if (initialized)
@@ -2054,7 +2074,7 @@ int grspw_dma_rx_recv(void *c, int opts, struct
grspw_list *pkts, int *count)
int cnt, started;
/* Take DMA channel lock */
- if (rtems_semaphore_obtain(dma->sem_dma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
+ if (rtems_semaphore_obtain(dma->sem_rxdma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
!= RTEMS_SUCCESSFUL)
return -1;
@@ -2099,7 +2119,7 @@ int grspw_dma_rx_recv(void *c, int opts, struct
grspw_list *pkts, int *count)
grspw_rx_schedule_ready(dma);
/* Unlock DMA channel */
- rtems_semaphore_release(dma->sem_dma);
+ rtems_semaphore_release(dma->sem_rxdma);
return (~started) & 1;
}
@@ -2110,7 +2130,7 @@ int grspw_dma_rx_prepare(void *c, int opts, struct
grspw_list *pkts, int count)
int ret;
/* Take DMA channel lock */
- if (rtems_semaphore_obtain(dma->sem_dma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
+ if (rtems_semaphore_obtain(dma->sem_rxdma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
!= RTEMS_SUCCESSFUL)
return -1;
@@ -2138,7 +2158,7 @@ int grspw_dma_rx_prepare(void *c, int opts, struct
grspw_list *pkts, int count)
ret = 0;
out:
/* Unlock DMA channel */
- rtems_semaphore_release(dma->sem_dma);
+ rtems_semaphore_release(dma->sem_rxdma);
return ret;
}
@@ -2155,7 +2175,7 @@ void grspw_dma_rx_count(void *c, int *ready, int *sched,
int *recv, int *hw)
* and that DMA descriptor table and rx_ring_tail is not being updated
* during HW counter processing in this function.
*/
- if (rtems_semaphore_obtain(dma->sem_dma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
+ if (rtems_semaphore_obtain(dma->sem_rxdma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
!= RTEMS_SUCCESSFUL)
return;
@@ -2185,7 +2205,7 @@ void grspw_dma_rx_count(void *c, int *ready, int *sched,
int *recv, int *hw)
}
/* Unlock DMA channel */
- rtems_semaphore_release(dma->sem_dma);
+ rtems_semaphore_release(dma->sem_rxdma);
}
static inline int grspw_rx_wait_eval(struct grspw_dma_priv *dma)
@@ -2226,7 +2246,7 @@ int grspw_dma_rx_wait(void *c, int recv_cnt, int op, int
ready_cnt, int timeout)
check_condition:
/* Take DMA channel lock */
- if (rtems_semaphore_obtain(dma->sem_dma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
+ if (rtems_semaphore_obtain(dma->sem_rxdma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
!= RTEMS_SUCCESSFUL)
return -1;
@@ -2255,7 +2275,7 @@ check_condition:
dma->rx_wait.waiting = 1;
/* Release channel lock */
- rtems_semaphore_release(dma->sem_dma);
+ rtems_semaphore_release(dma->sem_rxdma);
/* Try to take Wait lock, if this fail link may have gone down
* or user stopped this DMA channel
@@ -2286,7 +2306,7 @@ check_condition:
out_release:
/* Unlock DMA channel */
- rtems_semaphore_release(dma->sem_dma);
+ rtems_semaphore_release(dma->sem_rxdma);
out:
if (initialized)
@@ -2481,13 +2501,19 @@ void grspw_dma_stop(void *c)
return;
/* Take DMA Channel lock */
- if (rtems_semaphore_obtain(dma->sem_dma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
+ if (rtems_semaphore_obtain(dma->sem_rxdma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
!= RTEMS_SUCCESSFUL)
return;
+ if (rtems_semaphore_obtain(dma->sem_txdma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
+ != RTEMS_SUCCESSFUL) {
+ rtems_semaphore_release(dma->sem_rxdma);
+ return;
+ }
grspw_dma_stop_locked(dma);
- rtems_semaphore_release(dma->sem_dma);
+ rtems_semaphore_release(dma->sem_txdma);
+ rtems_semaphore_release(dma->sem_rxdma);
}
/* Do general work, invoked indirectly from ISR */
@@ -2519,24 +2545,19 @@ static void grspw_work_dma_func(struct grspw_dma_priv
*dma)
tx_cond_true = 0;
dma->stats.irq_cnt++;
- /* Take DMA channel lock */
- if (rtems_semaphore_obtain(dma->sem_dma, RTEMS_WAIT, RTEMS_NO_TIMEOUT)
- != 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);
+ if (dma->started == 0) {
+ SPIN_UNLOCK_IRQ(&priv->devlock, irqflags);
+ return;
+ }
ctrl = REG_READ(&dma->regs->ctrl);
/* Read/Write DMA error ? */
if (ctrl & GRSPW_DMA_STATUS_ERROR) {
/* DMA error -> Stop DMA channel (both RX and TX) */
SPIN_UNLOCK_IRQ(&priv->devlock, irqflags);
- grspw_dma_stop_locked(dma);
+ grspw_dma_stop(dma);
} else if (ctrl & (GRSPW_DMACTRL_PR | GRSPW_DMACTRL_PS)) {
/* DMA has finished a TX/RX packet */
ctrl &= ~GRSPW_DMACTRL_AT;
@@ -2550,30 +2571,49 @@ static void grspw_work_dma_func(struct grspw_dma_priv
*dma)
SPIN_UNLOCK_IRQ(&priv->devlock, irqflags);
if (ctrl & GRSPW_DMACTRL_PR) {
/* Do RX Work */
+
+ /* Take DMA channel RX lock */
+ if (rtems_semaphore_obtain(dma->sem_rxdma, RTEMS_WAIT,
RTEMS_NO_TIMEOUT)
+ != RTEMS_SUCCESSFUL)
+ return;
+
dma->stats.rx_work_cnt++;
grspw_rx_process_scheduled(dma);
- dma->stats.rx_work_enabled +=
grspw_rx_schedule_ready(dma);
- /* Check to see if condition for waking blocked USER
- * task is fullfilled.
- */
- if (dma->rx_wait.waiting)
- rx_cond_true = grspw_rx_wait_eval(dma);
+ if (dma->started) {
+ dma->stats.rx_work_enabled +=
+ grspw_rx_schedule_ready(dma);
+ /* Check to see if condition for waking blocked
+ * USER task is fullfilled.
+ */
+ if (dma->rx_wait.waiting)
+ rx_cond_true = grspw_rx_wait_eval(dma);
+ }
+ rtems_semaphore_release(dma->sem_rxdma);
}
if (ctrl & GRSPW_DMACTRL_PS) {
/* Do TX Work */
+
+ /* Take DMA channel TX lock */
+ if (rtems_semaphore_obtain(dma->sem_txdma, RTEMS_WAIT,
RTEMS_NO_TIMEOUT)
+ != RTEMS_SUCCESSFUL)
+ return;
+
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)
- tx_cond_true = grspw_tx_wait_eval(dma);
+ if (dma->started) {
+ dma->stats.tx_work_enabled +=
+ grspw_tx_schedule_send(dma);
+ /* Check to see if condition for waking blocked
+ * USER task is fullfilled.
+ */
+ if (dma->tx_wait.waiting)
+ tx_cond_true = grspw_tx_wait_eval(dma);
+ }
+ rtems_semaphore_release(dma->sem_txdma);
}
} else
SPIN_UNLOCK_IRQ(&priv->devlock, irqflags);
-out:
- /* Release lock */
- rtems_semaphore_release(dma->sem_dma);
-
if (rx_cond_true)
rtems_semaphore_release(dma->rx_wait.sem_wait);
--
2.7.4
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