[PATCH v2 1/5] dmaengine: ti: k3-udma: Remove dma_sync_single calls for descriptors

Peter Ujfalusi
2020-07-07T10:22:56Z

The descriptors are allocated via wither dma_pool or dma_alloc_coherent.

There is no need for the dma_sync_singel_* calls.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
drivers/dma/ti/k3-udma.c | 37 ++-----------------------------------
1 file changed, 2 insertions(+), 35 deletions(-)

diff --git a/drivers/dma/ti/k3-udma.c b/drivers/dma/ti/k3-udma.c
index 6c879a734360..919669634d87 100644
--- a/drivers/dma/ti/k3-udma.c
+++ b/drivers/dma/ti/k3-udma.c
@@ -539,30 +539,6 @@ static bool udma_is_chan_paused(struct udma_chan *uc)
return false;
}

-static void udma_sync_for_device(struct udma_chan *uc, int idx)
-{
- struct udma_desc *d = uc->desc;
-
- if (uc->cyclic && uc->config.pkt_mode) {
- dma_sync_single_for_device(uc->ud->dev,
- d->hwdesc[idx].cppi5_desc_paddr,
- d->hwdesc[idx].cppi5_desc_size,
- DMA_TO_DEVICE);
- } else {
- int i;
-
- for (i = 0; i < d->hwdesc_count; i++) {
- if (!d->hwdesc[i].cppi5_desc_vaddr)
- continue;
-
- dma_sync_single_for_device(uc->ud->dev,
- d->hwdesc[i].cppi5_desc_paddr,
- d->hwdesc[i].cppi5_desc_size,
- DMA_TO_DEVICE);
- }
- }
-}
-
static inline dma_addr_t udma_get_rx_flush_hwdesc_paddr(struct udma_chan *uc)
{
return uc->ud->rx_flush.hwdescs[uc->config.pkt_mode].cppi5_desc_paddr;
@@ -593,7 +569,6 @@ static int udma_push_to_ring(struct udma_chan *uc, int idx)
paddr = udma_curr_cppi5_desc_paddr(d, idx);

wmb(); /* Ensure that writes are not moved over this point */
- udma_sync_for_device(uc, idx);
}

return k3_ringacc_ring_push(ring, &paddr);
@@ -628,12 +603,12 @@ static int udma_pop_from_ring(struct udma_chan *uc, dma_addr_t *addr)
}

if (ring && k3_ringacc_ring_get_occ(ring)) {
- struct udma_desc *d = NULL;
-
ret = k3_ringacc_ring_pop(ring, addr);
if (ret)
return ret;

+ rmb(); /* Ensure that reads are not moved before this point */
+
/* Teardown completion */
if (cppi5_desc_is_tdcm(*addr))
return ret;
@@ -641,14 +616,6 @@ static int udma_pop_from_ring(struct udma_chan *uc, dma_addr_t *addr)
/* Check for flush descriptor */
if (udma_desc_is_rx_flush(uc, *addr))
return -ENOENT;
-
- d = udma_udma_desc_from_paddr(uc, *addr);
-
- if (d)
- dma_sync_single_for_cpu(uc->ud->dev, *addr,
- d->hwdesc[0].cppi5_desc_size,
- DMA_FROM_DEVICE);
- rmb(); /* Ensure that reads are not moved before this point */
}

return ret;