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lib: dma: simplify DMAC search and fix users to max channels #687

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Merged
lgirdwood merged 1 commit into from
Dec 17, 2018
Merged

lib: dma: simplify DMAC search and fix users to max channels #687

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76 changes: 48 additions & 28 deletions src/lib/dma.c
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Original file line number Diff line number Diff line change
Expand Up @@ -56,9 +56,11 @@ struct dma *dma_get(uint32_t dir, uint32_t cap, uint32_t dev, uint32_t flags)
struct dma *d = NULL, *dmin = NULL;

if (!lib_dma.num_dmas) {
trace_error(TRACE_CLASS_DMA, "dma_get(): No DMAs installed");
trace_error(TRACE_CLASS_DMA, "dma_get(): No DMACs installed");
return NULL;
}

/* find DMAC with free channels that matches request */
for (d = lib_dma.dma_array; d < lib_dma.dma_array + lib_dma.num_dmas;
d++) {
/* skip if this DMAC does not support the requested dir */
Expand All @@ -73,6 +75,11 @@ struct dma *dma_get(uint32_t dir, uint32_t cap, uint32_t dev, uint32_t flags)
if (dev && (d->plat_data.devs & dev) == 0)
continue;

/* skip if this DMAC has 1 user per avail channel */
/* TODO: this should be fixed in dai.c to allow more users */
if (d->sref >= d->plat_data.channels)
continue;

/* if exclusive access is requested */
if (flags & DMA_ACCESS_EXCLUSIVE) {

Expand All @@ -92,37 +99,50 @@ struct dma *dma_get(uint32_t dir, uint32_t cap, uint32_t dev, uint32_t flags)
}
}

if (!dmin) {
trace_error(TRACE_CLASS_DMA, "No DMAC dir %d caps 0x%x dev 0x%x flags 0x%x",
dir, cap, dev, flags);

for (d = lib_dma.dma_array; d < lib_dma.dma_array + lib_dma.num_dmas;
d++) {
trace_error(TRACE_CLASS_DMA, " DMAC ID %d users %d busy channels %d",
d->plat_data.id, d->sref,
atomic_read(&d->num_channels_busy));
trace_error(TRACE_CLASS_DMA, " caps 0x%x dev 0x%x",
d->plat_data.caps, d->plat_data.devs);
}
return NULL;
}

/* return DMAC */
if (dmin) {
tracev_event(TRACE_CLASS_DMA, "dma_get(), dma-probe id = %d",
dmin->plat_data.id);
/* Shared DMA controllers with multiple channels
* may be requested many times, let the probe()
* do on-first-use initialization.
*/
spin_lock(&dmin->lock);
ret = 0;
if (dmin->sref == 0) {
ret = dma_probe(dmin);
if (ret < 0) {
trace_error(TRACE_CLASS_DMA,
"dma_get() error: dma-probe failed"
" id = %d, ret = %d",
dmin->plat_data.id, ret);
}
tracev_event(TRACE_CLASS_DMA, "dma_get(), dma-probe id = %d",
dmin->plat_data.id);

/* Shared DMA controllers with multiple channels
* may be requested many times, let the probe()
* do on-first-use initialization.
*/
spin_lock(&dmin->lock);

ret = 0;
if (dmin->sref == 0) {
ret = dma_probe(dmin);
if (ret < 0) {
trace_error(TRACE_CLASS_DMA,
"dma_get() error: dma-probe failed"
" id = %d, ret = %d",
dmin->plat_data.id, ret);
}
if (!ret)
dmin->sref++;
trace_event(TRACE_CLASS_DMA, "dma_get(), dmin = %p, sref = %d",
(uintptr_t)dmin, dmin->sref);
spin_unlock(&dmin->lock);
return !ret ? dmin : NULL;
}
if (!ret)
dmin->sref++;

trace_event(TRACE_CLASS_DMA, "dma_get() ID %d sref = %d busy channels %d",
dmin->plat_data.id, dmin->sref,
atomic_read(&dmin->num_channels_busy));

trace_error(TRACE_CLASS_DMA,
"dma_get() error: dir = 0x%x, cap = 0x%x, dev = 0x%x, "
"flags = 0x%x not found", dir, cap, dev, flags);
return NULL;
spin_unlock(&dmin->lock);
return !ret ? dmin : NULL;
}

void dma_put(struct dma *dma)
Expand Down