Commit 56009f0d authored by Lars-Peter Clausen's avatar Lars-Peter Clausen Committed by Vinod Koul
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dmaengine: axi-dmac: Infer synthesis configuration parameters hardware 



Some synthesis time configuration parameters of the DMA controller can be
inferred from the hardware itself.

Use this information as it is more reliably than the information specified
in the devicetree which might be outdated if the HDL project got changed.

Deprecate the devicetree properties that can be inferred from the hardware
itself.

Signed-off-by: default avatarLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: default avatarAlexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent 38a829a3

Documentation/devicetree/bindings/dma/adi,axi-dmac.txt

+2 −2
Original line number Diff line number Diff line
@@ -18,7 +18,6 @@ Required properties for adi,channels sub-node: 


Required channel sub-node properties:

 - reg: Which channel this node refers to.

 - adi,length-width: Width of the DMA transfer length register.

 - adi,source-bus-width,

   adi,destination-bus-width: Width of the source or destination bus in bits.

 - adi,source-bus-type,
@@ -28,7 +27,8 @@ Required channel sub-node properties: 
	1 (AXI_DMAC_TYPE_AXI_STREAM): Streaming AXI interface

	2 (AXI_DMAC_TYPE_AXI_FIFO): FIFO interface



Optional channel properties:

Deprecated optional channel properties:

 - adi,length-width: Width of the DMA transfer length register.

 - adi,cyclic: Must be set if the channel supports hardware cyclic DMA

   transfers.

 - adi,2d: Must be set if the channel supports hardware 2D DMA transfers.

drivers/dma/dma-axi-dmac.c

+20 −12
Original line number Diff line number Diff line
@@ -618,15 +618,6 @@ static int axi_dmac_parse_chan_dt(struct device_node *of_chan, 
		return ret;

	chan->dest_width = val / 8;



	ret = of_property_read_u32(of_chan, "adi,length-width", &val);

	if (ret)

		return ret;



	if (val >= 32)

		chan->max_length = UINT_MAX;

	else

		chan->max_length = (1ULL << val) - 1;



	chan->align_mask = max(chan->dest_width, chan->src_width) - 1;



	if (axi_dmac_dest_is_mem(chan) && axi_dmac_src_is_mem(chan))
@@ -638,12 +629,27 @@ static int axi_dmac_parse_chan_dt(struct device_node *of_chan, 
	else

		chan->direction = DMA_DEV_TO_DEV;



	chan->hw_cyclic = of_property_read_bool(of_chan, "adi,cyclic");

	chan->hw_2d = of_property_read_bool(of_chan, "adi,2d");



	return 0;

}



static void axi_dmac_detect_caps(struct axi_dmac *dmac)

{

	struct axi_dmac_chan *chan = &dmac->chan;



	axi_dmac_write(dmac, AXI_DMAC_REG_FLAGS, AXI_DMAC_FLAG_CYCLIC);

	if (axi_dmac_read(dmac, AXI_DMAC_REG_FLAGS) == AXI_DMAC_FLAG_CYCLIC)

		chan->hw_cyclic = true;



	axi_dmac_write(dmac, AXI_DMAC_REG_Y_LENGTH, 1);

	if (axi_dmac_read(dmac, AXI_DMAC_REG_Y_LENGTH) == 1)

		chan->hw_2d = true;



	axi_dmac_write(dmac, AXI_DMAC_REG_X_LENGTH, 0xffffffff);

	chan->max_length = axi_dmac_read(dmac, AXI_DMAC_REG_X_LENGTH);

	if (chan->max_length != UINT_MAX)

		chan->max_length++;

}



static int axi_dmac_probe(struct platform_device *pdev)

{

	struct device_node *of_channels, *of_chan;
@@ -716,6 +722,8 @@ static int axi_dmac_probe(struct platform_device *pdev) 
	if (ret < 0)

		return ret;



	axi_dmac_detect_caps(dmac);



	axi_dmac_write(dmac, AXI_DMAC_REG_IRQ_MASK, 0x00);



	ret = dma_async_device_register(dma_dev);

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