[PATCH v5 0/3] dmaengine: arm-dma350: support combined IRQ mode with runtime IRQ topology detection

[PATCH v5 0/3] dmaengine: arm-dma350: support combined IRQ mode with runtime IRQ topology detection

[Jun Guo]

DMA-350 can be integrated with either one interrupt per channel or a
single combined interrupt for all channels. This series adds support
for the combined IRQ topology while keeping compatibility with the
per-channel topology.

Patch 1 updates the DT binding to describe both interrupt topologies
(1 combined IRQ or 8 per-channel IRQs).

Patch 2 updates the driver to detect IRQ topology at runtime via
platform_irq_count(), handle both modes in one code path, and enable
DMANSECCTRL.INTREN_ANYCHINTR only in combined IRQ mode.

Patch 3 adds the Sky1 DMA DT node using the combined IRQ topology.

Tested on CIX SKY1 with dmatest:
  % echo 2000 > /sys/module/dmatest/parameters/timeout
  % echo 1 > /sys/module/dmatest/parameters/iterations
  % echo "" > /sys/module/dmatest/parameters/channel
  % echo 1 > /sys/module/dmatest/parameters/run

Changes in v5:
- Fix the formatting issue in the AI tag.
- Remove the unnecessary "cix,sky1-dma-350".

Changes in v4:
- Reword binding text to align with kernel style.
- Revise the AI attribution to the standard format.
- Remove redundant links from the commit log.

Changes in v3:
- Rework binding compatible description to match generic-first model.
- Keep interrupts schema support for both 1-IRQ and 8-IRQ topologies.
- Drop SoC match-data dependency for IRQ mode selection.
- Detect IRQ topology via platform_irq_count() in probe path.
- Refactor IRQ handling into a shared channel handler.
- Enable DMANSECCTRL.INTREN_ANYCHINTR only in combined IRQ mode.

Changes in v2:
- Update to kernel standards, enhance patch description, and refactor
 driver to use match data for hardware differentiation instead of
 compatible strings.

Jun Guo (3):
  dt-bindings: dma: arm-dma350: document combined and per-channel IRQ
    topologies
  dma: arm-dma350: support combined IRQ mode with runtime IRQ topology
    detection
  arm64: dts: cix: add DT nodes for DMA

 .../devicetree/bindings/dma/arm,dma-350.yaml  |  25 ++-
 arch/arm64/boot/dts/cix/sky1.dtsi             |   7 +
 drivers/dma/arm-dma350.c                      | 164 +++++++++++++++---
 3 files changed, 161 insertions(+), 35 deletions(-)

-- 
2.34.1

[PATCH v5 1/3] dt-bindings: dma: arm-dma350: document combined and per-channel IRQ topologies

[Jun Guo]

Document the interrupt topologies supported by DMA-350 integration:
- one combined interrupt for all channels, or
- one interrupt per channel (up to 8 channels).

Assisted-by: Cursor:GPT-5.3-Codex
Signed-off-by: Jun Guo <jun.guo@cixtech.com>
---
 .../devicetree/bindings/dma/arm,dma-350.yaml  | 25 ++++++++++++-------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/Documentation/devicetree/bindings/dma/arm,dma-350.yaml b/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
index 429f682f15d8..bec9dc32541b 100644
--- a/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
+++ b/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
@@ -22,15 +22,22 @@ properties:
 
   interrupts:
     minItems: 1
-    items:
-      - description: Channel 0 interrupt
-      - description: Channel 1 interrupt
-      - description: Channel 2 interrupt
-      - description: Channel 3 interrupt
-      - description: Channel 4 interrupt
-      - description: Channel 5 interrupt
-      - description: Channel 6 interrupt
-      - description: Channel 7 interrupt
+    maxItems: 8
+    description:
+      Either one interrupt per channel (8 interrupts), or one
+      combined interrupt for all channels.
+    oneOf:
+      - items:
+          - description: Channel 0 interrupt
+          - description: Channel 1 interrupt
+          - description: Channel 2 interrupt
+          - description: Channel 3 interrupt
+          - description: Channel 4 interrupt
+          - description: Channel 5 interrupt
+          - description: Channel 6 interrupt
+          - description: Channel 7 interrupt
+      - items:
+          - description: Combined interrupt shared by all channels
 
   "#dma-cells":
     const: 1
-- 
2.34.1

[PATCH v5 2/3] dma: arm-dma350: support combined IRQ mode with runtime IRQ topology detection

[Jun Guo]

DMA-350 can be integrated with either per-channel IRQ lines or a single
combined IRQ line. Add support for both layouts in a unified way.

Detect IRQ topology at probe time via platform_irq_count(), then:
- request one global IRQ and enable DMANSECCTRL.INTREN_ANYCHINTR for
  combined mode, or
- request per-channel IRQs for channel mode.

Refactor IRQ completion/error handling into a shared channel handler
used by both global and per-channel IRQ paths, and guard against IRQs
arriving without an active descriptor.

Assisted-by: Cursor:GPT-5.3-Codex
Signed-off-by: Jun Guo <jun.guo@cixtech.com>
---
 drivers/dma/arm-dma350.c | 164 ++++++++++++++++++++++++++++++++-------
 1 file changed, 138 insertions(+), 26 deletions(-)

diff --git a/drivers/dma/arm-dma350.c b/drivers/dma/arm-dma350.c
index 84220fa83029..9e42c34b74bb 100644
--- a/drivers/dma/arm-dma350.c
+++ b/drivers/dma/arm-dma350.c
@@ -14,6 +14,7 @@
 #include "virt-dma.h"
 
 #define DMAINFO			0x0f00
+#define DRIVER_NAME		"arm-dma350"
 
 #define DMA_BUILDCFG0		0xb0
 #define DMA_CFG_DATA_WIDTH	GENMASK(18, 16)
@@ -142,6 +143,9 @@
 #define LINK_LINKADDR		BIT(30)
 #define LINK_LINKADDRHI		BIT(31)
 
+/* DMA NONSECURE CONTROL REGISTER */
+#define DMANSECCTRL		0x20c
+#define INTREN_ANYCHINTR_EN	BIT(0)
 
 enum ch_ctrl_donetype {
 	CH_CTRL_DONETYPE_NONE = 0,
@@ -192,6 +196,7 @@ struct d350_chan {
 
 struct d350 {
 	struct dma_device dma;
+	void __iomem *base;
 	int nchan;
 	int nreq;
 	struct d350_chan channels[] __counted_by(nchan);
@@ -461,18 +466,40 @@ static void d350_issue_pending(struct dma_chan *chan)
 	spin_unlock_irqrestore(&dch->vc.lock, flags);
 }
 
-static irqreturn_t d350_irq(int irq, void *data)
+static void d350_handle_chan_irq(struct d350_chan *dch, struct device *dev,
+				 int chan_id, u32 ch_status)
 {
-	struct d350_chan *dch = data;
-	struct device *dev = dch->vc.chan.device->dev;
-	struct virt_dma_desc *vd = &dch->desc->vd;
-	u32 ch_status;
+	struct virt_dma_desc *vd;
+	bool intr_done = ch_status & CH_STAT_INTR_DONE;
+	bool intr_err = ch_status & CH_STAT_INTR_ERR;
 
-	ch_status = readl(dch->base + CH_STATUS);
-	if (!ch_status)
-		return IRQ_NONE;
+	if (!intr_done && !intr_err) {
+		if (chan_id >= 0)
+			dev_warn(dev, "Channel %d unexpected IRQ: 0x%08x\n",
+				 chan_id, ch_status);
+		else
+			dev_warn(dev, "Unexpected IRQ source? 0x%08x\n", ch_status);
+		writel_relaxed(ch_status, dch->base + CH_STATUS);
+		return;
+	}
+
+	writel_relaxed(ch_status, dch->base + CH_STATUS);
+
+	spin_lock(&dch->vc.lock);
+	if (!dch->desc) {
+		if (chan_id >= 0)
+			dev_warn(dev,
+				 "Channel %d IRQ without active descriptor: 0x%08x\n",
+				 chan_id, ch_status);
+		else
+			dev_warn(dev, "IRQ without active descriptor: 0x%08x\n",
+				 ch_status);
+		spin_unlock(&dch->vc.lock);
+		return;
+	}
 
-	if (ch_status & CH_STAT_INTR_ERR) {
+	vd = &dch->desc->vd;
+	if (intr_err) {
 		u32 errinfo = readl_relaxed(dch->base + CH_ERRINFO);
 
 		if (errinfo & (CH_ERRINFO_AXIRDPOISERR | CH_ERRINFO_AXIRDRESPERR))
@@ -483,14 +510,10 @@ static irqreturn_t d350_irq(int irq, void *data)
 			vd->tx_result.result = DMA_TRANS_ABORTED;
 
 		vd->tx_result.residue = d350_get_residue(dch);
-	} else if (!(ch_status & CH_STAT_INTR_DONE)) {
-		dev_warn(dev, "Unexpected IRQ source? 0x%08x\n", ch_status);
 	}
-	writel_relaxed(ch_status, dch->base + CH_STATUS);
 
-	spin_lock(&dch->vc.lock);
 	vchan_cookie_complete(vd);
-	if (ch_status & CH_STAT_INTR_DONE) {
+	if (intr_done) {
 		dch->status = DMA_COMPLETE;
 		dch->residue = 0;
 		d350_start_next(dch);
@@ -499,6 +522,44 @@ static irqreturn_t d350_irq(int irq, void *data)
 		dch->residue = vd->tx_result.residue;
 	}
 	spin_unlock(&dch->vc.lock);
+}
+
+static irqreturn_t d350_global_irq(int irq, void *data)
+{
+	struct d350 *dmac = (struct d350 *)data;
+	irqreturn_t ret = IRQ_NONE;
+	int i;
+
+	(void)irq;
+
+	for (i = 0; i < dmac->nchan; i++) {
+		struct d350_chan *dch = &dmac->channels[i];
+		u32 ch_status;
+
+		ch_status = readl(dch->base + CH_STATUS);
+		if (!ch_status)
+			continue;
+
+		ret = IRQ_HANDLED;
+		d350_handle_chan_irq(dch, dmac->dma.dev, i, ch_status);
+	}
+
+	return ret;
+}
+
+static irqreturn_t d350_channel_irq(int irq, void *data)
+{
+	struct d350_chan *dch = data;
+	struct device *dev = dch->vc.chan.device->dev;
+	u32 ch_status;
+
+	(void)irq;
+
+	ch_status = readl(dch->base + CH_STATUS);
+	if (!ch_status)
+		return IRQ_NONE;
+
+	d350_handle_chan_irq(dch, dev, -1, ch_status);
 
 	return IRQ_HANDLED;
 }
@@ -506,10 +567,18 @@ static irqreturn_t d350_irq(int irq, void *data)
 static int d350_alloc_chan_resources(struct dma_chan *chan)
 {
 	struct d350_chan *dch = to_d350_chan(chan);
-	int ret = request_irq(dch->irq, d350_irq, IRQF_SHARED,
-			      dev_name(&dch->vc.chan.dev->device), dch);
-	if (!ret)
-		writel_relaxed(CH_INTREN_DONE | CH_INTREN_ERR, dch->base + CH_INTREN);
+	int ret = 0;
+
+	if (dch->irq >= 0) {
+		ret = request_irq(dch->irq, d350_channel_irq, IRQF_SHARED,
+				  dev_name(&dch->vc.chan.dev->device), dch);
+		if (ret) {
+			dev_err(chan->device->dev, "Failed to request IRQ %d\n", dch->irq);
+			return ret;
+		}
+	}
+
+	writel_relaxed(CH_INTREN_DONE | CH_INTREN_ERR, dch->base + CH_INTREN);
 
 	return ret;
 }
@@ -519,18 +588,21 @@ static void d350_free_chan_resources(struct dma_chan *chan)
 	struct d350_chan *dch = to_d350_chan(chan);
 
 	writel_relaxed(0, dch->base + CH_INTREN);
-	free_irq(dch->irq, dch);
+	if (dch->irq >= 0) {
+		free_irq(dch->irq, dch);
+		dch->irq = -EINVAL;
+	}
 	vchan_free_chan_resources(&dch->vc);
 }
 
 static int d350_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
-	struct d350 *dmac;
+	struct d350 *dmac = NULL;
 	void __iomem *base;
 	u32 reg;
-	int ret, nchan, dw, aw, r, p;
-	bool coherent, memset;
+	int ret, nchan, dw, aw, r, p, irq_count;
+	bool coherent, memset, combined_irq;
 
 	base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(base))
@@ -556,6 +628,7 @@ static int d350_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	dmac->nchan = nchan;
+	dmac->base = base;
 
 	reg = readl_relaxed(base + DMAINFO + DMA_BUILDCFG1);
 	dmac->nreq = FIELD_GET(DMA_CFG_NUM_TRIGGER_IN, reg);
@@ -582,12 +655,46 @@ static int d350_probe(struct platform_device *pdev)
 	dmac->dma.device_issue_pending = d350_issue_pending;
 	INIT_LIST_HEAD(&dmac->dma.channels);
 
+	irq_count = platform_irq_count(pdev);
+	if (irq_count < 0)
+		return dev_err_probe(dev, irq_count,
+				     "Failed to count interrupts\n");
+
+	if (irq_count == 1) {
+		combined_irq = true;
+	} else if (irq_count >= nchan) {
+		combined_irq = false;
+	} else {
+		return dev_err_probe(dev, -EINVAL,
+				     "Invalid IRQ count %d for %d channels\n",
+				     irq_count, nchan);
+	}
+
+	if (combined_irq) {
+		int host_irq = platform_get_irq(pdev, 0);
+
+		if (host_irq < 0)
+			return dev_err_probe(dev, host_irq,
+					     "Failed to get IRQ\n");
+
+		ret = devm_request_irq(&pdev->dev, host_irq, d350_global_irq,
+				       IRQF_SHARED, DRIVER_NAME, dmac);
+		if (ret)
+			return dev_err_probe(
+				dev, ret,
+				"Failed to request the combined IRQ %d\n",
+				host_irq);
+		/* Combined Non-Secure Channel Interrupt Enable */
+		writel_relaxed(INTREN_ANYCHINTR_EN, dmac->base + DMANSECCTRL);
+	}
+
 	/* Would be nice to have per-channel caps for this... */
 	memset = true;
 	for (int i = 0; i < nchan; i++) {
 		struct d350_chan *dch = &dmac->channels[i];
 
 		dch->base = base + DMACH(i);
+		dch->irq = -EINVAL;
 		writel_relaxed(CH_CMD_CLEAR, dch->base + CH_CMD);
 
 		reg = readl_relaxed(dch->base + CH_BUILDCFG1);
@@ -595,10 +702,15 @@ static int d350_probe(struct platform_device *pdev)
 			dev_warn(dev, "No command link support on channel %d\n", i);
 			continue;
 		}
-		dch->irq = platform_get_irq(pdev, i);
-		if (dch->irq < 0)
-			return dev_err_probe(dev, dch->irq,
-					     "Failed to get IRQ for channel %d\n", i);
+
+		if (!combined_irq) {
+			dch->irq = platform_get_irq(pdev, i);
+			if (dch->irq < 0)
+				return dev_err_probe(
+					dev, dch->irq,
+					"Failed to get IRQ for channel %d\n",
+					i);
+		}
 
 		dch->has_wrap = FIELD_GET(CH_CFG_HAS_WRAP, reg);
 		dch->has_trig = FIELD_GET(CH_CFG_HAS_TRIGIN, reg) &
-- 
2.34.1

[PATCH v5 3/3] arm64: dts: cix: add DT nodes for DMA

[Jun Guo]

Add the device tree node for the dma controller of the CIX SKY1 SoC.

Signed-off-by: Jun Guo <jun.guo@cixtech.com>
---
 arch/arm64/boot/dts/cix/sky1.dtsi | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/arm64/boot/dts/cix/sky1.dtsi b/arch/arm64/boot/dts/cix/sky1.dtsi
index 210739beac6d..124a29147c6c 100644
--- a/arch/arm64/boot/dts/cix/sky1.dtsi
+++ b/arch/arm64/boot/dts/cix/sky1.dtsi
@@ -480,6 +480,13 @@ iomuxc: pinctrl@4170000 {
 			reg = <0x0 0x04170000 0x0 0x1000>;
 		};
 
+		fch_dmac: dma-controller@4190000 {
+			compatible = "arm,dma-350";
+			reg = <0x0 0x4190000 0x0 0x10000>;
+			interrupts = <GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>;
+			#dma-cells = <1>;
+		};
+
 		mbox_ap2se: mailbox@5060000 {
 			compatible = "cix,sky1-mbox";
 			reg = <0x0 0x05060000 0x0 0x10000>;
-- 
2.34.1

Re: [PATCH v5 0/3] dmaengine: arm-dma350: support combined IRQ mode with runtime IRQ topology detection

[Robin Murphy]

On 2026-03-24 12:01 pm, Jun Guo wrote:
> DMA-350 can be integrated with either one interrupt per channel or a
> single combined interrupt for all channels. This series adds support
> for the combined IRQ topology while keeping compatibility with the
> per-channel topology.
> 
> Patch 1 updates the DT binding to describe both interrupt topologies
> (1 combined IRQ or 8 per-channel IRQs).
> 
> Patch 2 updates the driver to detect IRQ topology at runtime via
> platform_irq_count(), handle both modes in one code path, and enable
> DMANSECCTRL.INTREN_ANYCHINTR only in combined IRQ mode.
> 
> Patch 3 adds the Sky1 DMA DT node using the combined IRQ topology.
> 
> Tested on CIX SKY1 with dmatest:
>    % echo 2000 > /sys/module/dmatest/parameters/timeout
>    % echo 1 > /sys/module/dmatest/parameters/iterations
>    % echo "" > /sys/module/dmatest/parameters/channel
>    % echo 1 > /sys/module/dmatest/parameters/run
> 
> Changes in v5:
> - Fix the formatting issue in the AI tag.
> - Remove the unnecessary "cix,sky1-dma-350".

Please don't churn reposts of a series so quickly. I've only just had 
time to finish the review of v3 that you posted only 3 working days ago, 
that I already moved over as a reply to yesterday's v4 for visibility...

Thanks,
Robin.

> Changes in v4:
> - Reword binding text to align with kernel style.
> - Revise the AI attribution to the standard format.
> - Remove redundant links from the commit log.
> 
> Changes in v3:
> - Rework binding compatible description to match generic-first model.
> - Keep interrupts schema support for both 1-IRQ and 8-IRQ topologies.
> - Drop SoC match-data dependency for IRQ mode selection.
> - Detect IRQ topology via platform_irq_count() in probe path.
> - Refactor IRQ handling into a shared channel handler.
> - Enable DMANSECCTRL.INTREN_ANYCHINTR only in combined IRQ mode.
> 
> Changes in v2:
> - Update to kernel standards, enhance patch description, and refactor
>   driver to use match data for hardware differentiation instead of
>   compatible strings.
> 
> Jun Guo (3):
>    dt-bindings: dma: arm-dma350: document combined and per-channel IRQ
>      topologies
>    dma: arm-dma350: support combined IRQ mode with runtime IRQ topology
>      detection
>    arm64: dts: cix: add DT nodes for DMA
> 
>   .../devicetree/bindings/dma/arm,dma-350.yaml  |  25 ++-
>   arch/arm64/boot/dts/cix/sky1.dtsi             |   7 +
>   drivers/dma/arm-dma350.c                      | 164 +++++++++++++++---
>   3 files changed, 161 insertions(+), 35 deletions(-)
>