[PATCH v4 0/3] riscv: sophgo: allow DMA multiplexer set channel number for DMA controller

[PATCH v4 0/3] riscv: sophgo: allow DMA multiplexer set channel number for DMA controller

[Inochi Amaoto]

As the DMA controller on Sophgo CV1800 series SoC only has 8 channels,
the SoC provides a dma multiplexer to reuse the DMA channel. However,
the dma multiplexer also controlls the DMA interrupt multiplexer, which
means that the dma multiplexer needs to know the channel number.

Change the DMA phandle args parsing logic so it can use handshake
number as channel number if necessary.

Change from v3:
- https://lore.kernel.org/all/20260120013706.436742-1-inochiama@gmail.com/
1. rebase to v7.0-rc1
2. patch 1: Apply Conor's tag
3. patch 2: Apply Frank's tag

Change from v2:
- https://lore.kernel.org/all/20251214224601.598358-1-inochiama@gmail.com/
1. patch 2: rename "AXI_DMA_FLAG_HANDSHAKE_AS_CHAN" to "ARG0_AS_CHAN"

Change from v1:
- https://lore.kernel.org/all/20251212020504.915616-1-inochiama@gmail.com/
1. rebase to v6.19-rc1
2. patch 1: remove a comment placed in wrong place.
3. patch 2: fix typo in comments.
4. patch 2: initialize chan as NULL in dw_axi_dma_of_xlate.

Inochi Amaoto (3):
  dt-bindings: dma: snps,dw-axi-dmac: Add CV1800B compatible
  dmaengine: dw-axi-dmac: Add support for CV1800B DMA
  riscv: dts: sophgo: cv180x: Allow the DMA multiplexer to set channel
    number for DMA controller

 .../bindings/dma/snps,dw-axi-dmac.yaml        |  1 +
 arch/riscv/boot/dts/sophgo/cv180x.dtsi        |  2 +-
 .../dma/dw-axi-dmac/dw-axi-dmac-platform.c    | 25 ++++++++++++++++---
 drivers/dma/dw-axi-dmac/dw-axi-dmac.h         |  1 +
 4 files changed, 24 insertions(+), 5 deletions(-)

--
2.53.0

[PATCH v4 1/3] dt-bindings: dma: snps,dw-axi-dmac: Add CV1800B compatible

[Inochi Amaoto]

The DMA controller on CV1800B needs to use the DMA phandle args
as the channel number instead of hardware handshake number, so
add a new compatible for the DMA controller on CV1800B.

Signed-off-by: Inochi Amaoto <inochiama@gmail.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
---
 Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml b/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml
index 216cda21c538..96b0233d9b1b 100644
--- a/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml
+++ b/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml
@@ -21,6 +21,7 @@ properties:
       - enum:
           - snps,axi-dma-1.01a
           - intel,kmb-axi-dma
+          - sophgo,cv1800b-axi-dma
           - starfive,jh7110-axi-dma
           - starfive,jh8100-axi-dma
       - items:
-- 
2.53.0

[PATCH v4 2/3] dmaengine: dw-axi-dmac: Add support for CV1800B DMA

[Inochi Amaoto]

As the DMA controller on Sophgo CV1800 series SoC only has 8 channels,
the SoC provides a dma multiplexer to reuse the DMA channel. However,
the dma multiplexer also controls the DMA interrupt multiplexer, which
means that the dma multiplexer needs to know the channel number.

Allow the driver to use DMA phandle args as the channel number, so the
DMA multiplexer can route the DMA interrupt correctly.

Signed-off-by: Inochi Amaoto <inochiama@gmail.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
---
 .../dma/dw-axi-dmac/dw-axi-dmac-platform.c    | 25 ++++++++++++++++---
 drivers/dma/dw-axi-dmac/dw-axi-dmac.h         |  1 +
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index 5d74bc29cf89..ada6dfc9b673 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -50,6 +50,7 @@
 #define AXI_DMA_FLAG_HAS_APB_REGS	BIT(0)
 #define AXI_DMA_FLAG_HAS_RESETS		BIT(1)
 #define AXI_DMA_FLAG_USE_CFG2		BIT(2)
+#define AXI_DMA_FLAG_ARG0_AS_CHAN	BIT(3)
 
 static inline void
 axi_dma_iowrite32(struct axi_dma_chip *chip, u32 reg, u32 val)
@@ -1358,16 +1359,27 @@ static int __maybe_unused axi_dma_runtime_resume(struct device *dev)
 static struct dma_chan *dw_axi_dma_of_xlate(struct of_phandle_args *dma_spec,
 					    struct of_dma *ofdma)
 {
+	unsigned int handshake = dma_spec->args[0];
 	struct dw_axi_dma *dw = ofdma->of_dma_data;
-	struct axi_dma_chan *chan;
+	struct axi_dma_chan *chan = NULL;
 	struct dma_chan *dchan;
 
-	dchan = dma_get_any_slave_channel(&dw->dma);
+	if (dw->hdata->use_handshake_as_channel_number) {
+		if (handshake >= dw->hdata->nr_channels)
+			return NULL;
+
+		chan = &dw->chan[handshake];
+		dchan = dma_get_slave_channel(&chan->vc.chan);
+	} else {
+		dchan = dma_get_any_slave_channel(&dw->dma);
+	}
+
 	if (!dchan)
 		return NULL;
 
-	chan = dchan_to_axi_dma_chan(dchan);
-	chan->hw_handshake_num = dma_spec->args[0];
+	if (!chan)
+		chan = dchan_to_axi_dma_chan(dchan);
+	chan->hw_handshake_num = handshake;
 	return dchan;
 }
 
@@ -1506,6 +1518,8 @@ static int dw_probe(struct platform_device *pdev)
 			return ret;
 	}
 
+	chip->dw->hdata->use_handshake_as_channel_number = !!(flags & AXI_DMA_FLAG_ARG0_AS_CHAN);
+
 	chip->dw->hdata->use_cfg2 = !!(flags & AXI_DMA_FLAG_USE_CFG2);
 
 	chip->core_clk = devm_clk_get(chip->dev, "core-clk");
@@ -1661,6 +1675,9 @@ static const struct of_device_id dw_dma_of_id_table[] = {
 	}, {
 		.compatible = "intel,kmb-axi-dma",
 		.data = (void *)AXI_DMA_FLAG_HAS_APB_REGS,
+	}, {
+		.compatible = "sophgo,cv1800b-axi-dma",
+		.data = (void *)AXI_DMA_FLAG_ARG0_AS_CHAN,
 	}, {
 		.compatible = "starfive,jh7110-axi-dma",
 		.data = (void *)(AXI_DMA_FLAG_HAS_RESETS | AXI_DMA_FLAG_USE_CFG2),
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
index b842e6a8d90d..67cc199e24d1 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
@@ -34,6 +34,7 @@ struct dw_axi_dma_hcfg {
 	bool	reg_map_8_channels;
 	bool	restrict_axi_burst_len;
 	bool	use_cfg2;
+	bool	use_handshake_as_channel_number;
 };
 
 struct axi_dma_chan {
-- 
2.53.0

[PATCH v4 3/3] riscv: dts: sophgo: cv180x: Allow the DMA multiplexer to set channel number for DMA controller

[Inochi Amaoto]

Change the DMA controller compatible to the sophgo,cv1800b-axi-dma,
which supports setting DMA channel number in DMA phandle args.

Fixes: 514951a81a5e ("riscv: dts: sophgo: cv18xx: add DMA controller")
Reported-by: Anton D. Stavinskii <stavinsky@gmail.com>
Closes: https://github.com/sophgo/linux/issues/9
Signed-off-by: Inochi Amaoto <inochiama@gmail.com>
Tested-by: Anton D. Stavinskii <stavinsky@gmail.com>
---
 arch/riscv/boot/dts/sophgo/cv180x.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/boot/dts/sophgo/cv180x.dtsi b/arch/riscv/boot/dts/sophgo/cv180x.dtsi
index 06b0ce5a2db7..8446b4dfe1a1 100644
--- a/arch/riscv/boot/dts/sophgo/cv180x.dtsi
+++ b/arch/riscv/boot/dts/sophgo/cv180x.dtsi
@@ -417,7 +417,7 @@ sdhci1: mmc@4320000 {
 		};
 
 		dmac: dma-controller@4330000 {
-			compatible = "snps,axi-dma-1.01a";
+			compatible = "sophgo,cv1800b-axi-dma";
 			reg = <0x04330000 0x1000>;
 			interrupts = <SOC_PERIPHERAL_IRQ(13) IRQ_TYPE_LEVEL_HIGH>;
 			clocks = <&clk CLK_SDMA_AXI>, <&clk CLK_SDMA_AXI>;
-- 
2.53.0

Re: (subset) [PATCH v4 0/3] riscv: sophgo: allow DMA multiplexer set channel number for DMA controller

[Inochi Amaoto]

On Wed, 25 Feb 2026 18:40:38 +0800, Inochi Amaoto wrote:
> As the DMA controller on Sophgo CV1800 series SoC only has 8 channels,
> the SoC provides a dma multiplexer to reuse the DMA channel. However,
> the dma multiplexer also controlls the DMA interrupt multiplexer, which
> means that the dma multiplexer needs to know the channel number.
> 
> Change the DMA phandle args parsing logic so it can use handshake
> number as channel number if necessary.
> 
> [...]

Applied to dt/riscv, thanks!

[3/3] riscv: dts: sophgo: cv180x: Allow the DMA multiplexer to set channel number for DMA controller
      https://github.com/sophgo/linux/commit/7b159ed9c81cf7e0d0b75666e6548ceface2e1b5

Thanks,
Inochi