Instead of notifying userspace in the end-of-transfer (EOT) interrupt
and program the hardware in the start-of-transfer (SOT) interrupt, we
can do both things in the EOT, allowing us to mask the SOT, and halve
the number of interrupts sent by the HDL core.
Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
---
v2: Make sure cyclic buffers are restarted as well
---
drivers/dma/dma-axi-dmac.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/dma/dma-axi-dmac.c b/drivers/dma/dma-axi-dmac.c
index 5109530b66de..f63acae511fb 100644
--- a/drivers/dma/dma-axi-dmac.c
+++ b/drivers/dma/dma-axi-dmac.c
@@ -411,10 +411,12 @@ static bool axi_dmac_transfer_done(struct axi_dmac_chan *chan,
if (chan->hw_sg) {
if (active->cyclic) {
vchan_cyclic_callback(&active->vdesc);
+ start_next = true;
} else {
list_del(&active->vdesc.node);
vchan_cookie_complete(&active->vdesc);
active = axi_dmac_active_desc(chan);
+ start_next = !!active;
}
} else {
do {
@@ -1000,6 +1002,7 @@ static int axi_dmac_probe(struct platform_device *pdev)
struct axi_dmac *dmac;
struct regmap *regmap;
unsigned int version;
+ u32 irq_mask = 0;
int ret;
dmac = devm_kzalloc(&pdev->dev, sizeof(*dmac), GFP_KERNEL);
@@ -1067,7 +1070,10 @@ static int axi_dmac_probe(struct platform_device *pdev)
dma_dev->copy_align = (dmac->chan.address_align_mask + 1);
- axi_dmac_write(dmac, AXI_DMAC_REG_IRQ_MASK, 0x00);
+ if (dmac->chan.hw_sg)
+ irq_mask |= AXI_DMAC_IRQ_SOT;
+
+ axi_dmac_write(dmac, AXI_DMAC_REG_IRQ_MASK, irq_mask);
if (of_dma_is_coherent(pdev->dev.of_node)) {
ret = axi_dmac_read(dmac, AXI_DMAC_REG_COHERENCY_DESC);
--
2.42.0
