Commit 238f68a0 authored by Paul Cercueil's avatar Paul Cercueil Committed by Vinod Koul
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dmaengine: axi-dmac: Use only EOT interrupts when doing scatter-gather 



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: default avatarPaul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20231215131313.23840-5-paul@crapouillou.net


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent e97dc743

drivers/dma/dma-axi-dmac.c

+7 −1
Original line number Diff line number Diff line
@@ -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);