[PATCH v4 0/3] Reserve eDMA channels 0-1 for V2X

[PATCH v4 0/3] Reserve eDMA channels 0-1 for V2X

[Joy Zou]

---
Changes in v4:
- add dt-binding patch to document dma-channel-mask usage in the fsl-edma binding.
- Link to v3: https://lore.kernel.org/r/20260130-b4-imx95-v2x-v3-0-95af05bece95@nxp.com

Changes in v3:
- extract the imx95-19x19-evk-sof.dts changes into a separate patch.
- Link to v2: https://lore.kernel.org/r/20260123-b4-imx95-v2x-v2-1-0497a9814668@nxp.com

Changes in v2:
- modify imx95-19x19-evk-sof.dts dma-channel-mask property.
- add comments for mask channel.
- add Reviewed-by and Tested-by tag, tested on MX95-15x15-FRDM, MX95-19x19-EVK.
- Link to v1: https://lore.kernel.org/r/20260120-b4-imx95-v2x-v1-1-52b2025b27a0@nxp.com

---
Joy Zou (3):
      dt-bindings: dma: fsl-edma: add dma-channel-mask property description
      arm64: dts: imx95: Reserve eDMA channels 0-1 for V2X
      arm64: dts: imx95-evk: update the dma-channel-mask property

 Documentation/devicetree/bindings/dma/fsl,edma.yaml   | 9 +++++++++
 arch/arm64/boot/dts/freescale/imx95-19x19-evk-sof.dts | 7 +++++--
 arch/arm64/boot/dts/freescale/imx95.dtsi              | 2 ++
 3 files changed, 16 insertions(+), 2 deletions(-)
---
base-commit: 4c87cdd0328495759f6e9f9f4e1e53ef8032a76f
change-id: 20260120-b4-imx95-v2x-3e01c7bc6881

Best regards,
-- 
Joy Zou <joy.zou@nxp.com>

[PATCH v4 1/3] dt-bindings: dma: fsl-edma: add dma-channel-mask property description

[Joy Zou]

Add documentation for the dma-channel-mask property in the fsl-edma
binding. This property uses an inverted bit definition: bit value 0
indicates the channel is available, while bit value 1 indicates
unavailable.

That was already used widely for i.MX8, i.MX9. Correcting the definition
will break backward compatibility. This reversal only impacts the eDMA
dts node and driver, and doesn't impact DMA consumer. Therefore,
keep the inverted definition.

Also add a note at the top of the binding to highlight this inverted
definition to prevent confusion.

Signed-off-by: Joy Zou <joy.zou@nxp.com>
---
 Documentation/devicetree/bindings/dma/fsl,edma.yaml | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/devicetree/bindings/dma/fsl,edma.yaml b/Documentation/devicetree/bindings/dma/fsl,edma.yaml
index fa4248e2f1b9cecd00f1535744bfe6d9ecdba613..f609038e35ae1836b89c5b4d8a095b15a882fb87 100644
--- a/Documentation/devicetree/bindings/dma/fsl,edma.yaml
+++ b/Documentation/devicetree/bindings/dma/fsl,edma.yaml
@@ -12,6 +12,9 @@ description: |
   DMAMUX0 and DMAMUX1, specific DMA request source can only be multiplexed
   by any channel of certain group, DMAMUX0 or DMAMUX1, but not both.
 
+  This binding has an inverted dma-channel-mask definition compared to
+  the common DMA binding for historical reasons.
+
 maintainers:
   - Peng Fan <peng.fan@nxp.com>
 
@@ -95,6 +98,12 @@ properties:
       eDMA are implemented in big endian mode, otherwise in little mode.
     type: boolean
 
+  dma-channel-mask:
+    description: |
+      Bitmask of available DMA channels (inverted definition).
+      Bit semantics: 0 means channel available, 1 means channel unavailable
+    default: 0
+
 required:
   - "#dma-cells"
   - compatible

-- 
2.37.1

Re: [PATCH v4 1/3] dt-bindings: dma: fsl-edma: add dma-channel-mask property description

[Frank Li]

On Wed, Feb 11, 2026 at 05:28:24PM +0800, Joy Zou wrote:
> Add documentation for the dma-channel-mask property in the fsl-edma
> binding. This property uses an inverted bit definition: bit value 0
> indicates the channel is available, while bit value 1 indicates
> unavailable.
>
> That was already used widely for i.MX8, i.MX9. Correcting the definition
> will break backward compatibility. This reversal only impacts the eDMA
> dts node and driver, and doesn't impact DMA consumer. Therefore,
> keep the inverted definition.
>
> Also add a note at the top of the binding to highlight this inverted
> definition to prevent confusion.
>
> Signed-off-by: Joy Zou <joy.zou@nxp.com>
> ---
Reviewed-by: Frank Li <Frank.Li@nxp.com>
>  Documentation/devicetree/bindings/dma/fsl,edma.yaml | 9 +++++++++
>  1 file changed, 9 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/dma/fsl,edma.yaml b/Documentation/devicetree/bindings/dma/fsl,edma.yaml
> index fa4248e2f1b9cecd00f1535744bfe6d9ecdba613..f609038e35ae1836b89c5b4d8a095b15a882fb87 100644
> --- a/Documentation/devicetree/bindings/dma/fsl,edma.yaml
> +++ b/Documentation/devicetree/bindings/dma/fsl,edma.yaml
> @@ -12,6 +12,9 @@ description: |
>    DMAMUX0 and DMAMUX1, specific DMA request source can only be multiplexed
>    by any channel of certain group, DMAMUX0 or DMAMUX1, but not both.
>
> +  This binding has an inverted dma-channel-mask definition compared to
> +  the common DMA binding for historical reasons.
> +
>  maintainers:
>    - Peng Fan <peng.fan@nxp.com>
>
> @@ -95,6 +98,12 @@ properties:
>        eDMA are implemented in big endian mode, otherwise in little mode.
>      type: boolean
>
> +  dma-channel-mask:
> +    description: |
> +      Bitmask of available DMA channels (inverted definition).
> +      Bit semantics: 0 means channel available, 1 means channel unavailable
> +    default: 0
> +
>  required:
>    - "#dma-cells"
>    - compatible
>
> --
> 2.37.1
>

Re: [PATCH v4 1/3] dt-bindings: dma: fsl-edma: add dma-channel-mask property description

[Rob Herring (Arm)]

On Wed, 11 Feb 2026 17:28:24 +0800, Joy Zou wrote:
> Add documentation for the dma-channel-mask property in the fsl-edma
> binding. This property uses an inverted bit definition: bit value 0
> indicates the channel is available, while bit value 1 indicates
> unavailable.
> 
> That was already used widely for i.MX8, i.MX9. Correcting the definition
> will break backward compatibility. This reversal only impacts the eDMA
> dts node and driver, and doesn't impact DMA consumer. Therefore,
> keep the inverted definition.
> 
> Also add a note at the top of the binding to highlight this inverted
> definition to prevent confusion.
> 
> Signed-off-by: Joy Zou <joy.zou@nxp.com>
> ---
>  Documentation/devicetree/bindings/dma/fsl,edma.yaml | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 

Acked-by: Rob Herring (Arm) <robh@kernel.org>

Re: [PATCH v4 1/3] dt-bindings: dma: fsl-edma: add dma-channel-mask property description

[Laurentiu Mihalcea]

On 2/11/2026 1:28 AM, Joy Zou wrote:
> Add documentation for the dma-channel-mask property in the fsl-edma
> binding. This property uses an inverted bit definition: bit value 0
> indicates the channel is available, while bit value 1 indicates
> unavailable.
> 
> That was already used widely for i.MX8, i.MX9. Correcting the definition
> will break backward compatibility. This reversal only impacts the eDMA
> dts node and driver, and doesn't impact DMA consumer. Therefore,
> keep the inverted definition.
> 
> Also add a note at the top of the binding to highlight this inverted
> definition to prevent confusion.
> 
> Signed-off-by: Joy Zou <joy.zou@nxp.com>
Hi,

I believe this patch hasn't been picked up yet even though it's been ACK'd by one of the
DT binding maintainers.

Frank Li, can you please take it into your tree?


Thanks,
Laurentiu

Re: [PATCH v4 1/3] dt-bindings: dma: fsl-edma: add dma-channel-mask property description

[Frank Li]

On Fri, Jun 05, 2026 at 03:44:23AM -0700, Laurentiu Mihalcea wrote:
>
>
> On 2/11/2026 1:28 AM, Joy Zou wrote:
> > Add documentation for the dma-channel-mask property in the fsl-edma
> > binding. This property uses an inverted bit definition: bit value 0
> > indicates the channel is available, while bit value 1 indicates
> > unavailable.
> >
> > That was already used widely for i.MX8, i.MX9. Correcting the definition
> > will break backward compatibility. This reversal only impacts the eDMA
> > dts node and driver, and doesn't impact DMA consumer. Therefore,
> > keep the inverted definition.
> >
> > Also add a note at the top of the binding to highlight this inverted
> > definition to prevent confusion.
> >
> > Signed-off-by: Joy Zou <joy.zou@nxp.com>
> Hi,
>
> I believe this patch hasn't been picked up yet even though it's been ACK'd by one of the
> DT binding maintainers.
>
> Frank Li, can you please take it into your tree?

I ping vnod in irc yesterday, let wait for few days, if he don't pick, I
will pick it.

Frank
>
>
> Thanks,
> Laurentiu

[PATCH v4 2/3] arm64: dts: imx95: Reserve eDMA channels 0-1 for V2X

[Joy Zou]

Reserve eDMA channels 0 and 1 on the AXI eDMA controller for exclusive
use by V2X (Vehicle-to-Everything) fast hash operations.

Reviewed-by: Laurentiu Mihalcea <laurentiu.mihalcea@nxp.com>
Tested-by: Laurentiu Mihalcea <laurentiu.mihalcea@nxp.com>
Signed-off-by: Joy Zou <joy.zou@nxp.com>
---
 arch/arm64/boot/dts/freescale/imx95.dtsi | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm64/boot/dts/freescale/imx95.dtsi b/arch/arm64/boot/dts/freescale/imx95.dtsi
index 55e2da094c889fc7c1096d0e36f31ae118d2a982..9ac82da2ff440e08ae8378d7ff830a568d50a354 100644
--- a/arch/arm64/boot/dts/freescale/imx95.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx95.dtsi
@@ -631,6 +631,8 @@ edma2: dma-controller@42000000 {
 				reg = <0x42000000 0x210000>;
 				#dma-cells = <3>;
 				dma-channels = <64>;
+				/* channels 0 and 1 reserved for V2X fast hash */
+				dma-channel-mask = <0x3>;
 				interrupts = <GIC_SPI 128 IRQ_TYPE_LEVEL_HIGH>,
 					     <GIC_SPI 128 IRQ_TYPE_LEVEL_HIGH>,
 					     <GIC_SPI 129 IRQ_TYPE_LEVEL_HIGH>,

-- 
2.37.1

[PATCH v4 3/3] arm64: dts: imx95-evk: update the dma-channel-mask property

[Joy Zou]

Have reserved eDMA2 channels 0 and 1 for V2X fast hash in imx95.dtsi.
So update the dma-channel-mask from 0xc0000000 to 0xc0000003 to mark
channels 0, 1, 30, and 31 as reserved.

Signed-off-by: Joy Zou <joy.zou@nxp.com>
---
 arch/arm64/boot/dts/freescale/imx95-19x19-evk-sof.dts | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/freescale/imx95-19x19-evk-sof.dts b/arch/arm64/boot/dts/freescale/imx95-19x19-evk-sof.dts
index 808a9fe3ebb2b9557be9e428583e76c32517de08..264703f6eef64813d64fe07713cf92fd02fa0778 100644
--- a/arch/arm64/boot/dts/freescale/imx95-19x19-evk-sof.dts
+++ b/arch/arm64/boot/dts/freescale/imx95-19x19-evk-sof.dts
@@ -55,8 +55,11 @@ sound-wm8962 {
 };
 
 &edma2 {
-	/* channels 30 and 31 reserved for FW usage */
-	dma-channel-mask = <0xc0000000>, <0x0>;
+	/*
+	 * channels 0 and 1 reserved for V2X fast hash,
+	 * channels 30 and 31 reserved for FW usage
+	 */
+	dma-channel-mask = <0xc0000003>, <0x0>;
 };
 
 &sai3 {

-- 
2.37.1

Re: (subset) [PATCH v4 0/3] Reserve eDMA channels 0-1 for V2X

[Frank Li]

On Wed, 11 Feb 2026 17:28:23 +0800, Joy Zou wrote:
> 
> 

Applied, thanks!

[2/3] arm64: dts: imx95: Reserve eDMA channels 0-1 for V2X
      (no commit info)
[3/3] arm64: dts: imx95-evk: update the dma-channel-mask property
      (no commit info)

Best regards,
--
Frank Li <Frank.Li@nxp.com>