| Message ID | 20241010-dma3-mp25-updates-v1-6-adf0633981ea@foss.st.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | STM32 DMA3 updates for STM32MP25 | expand |
On Thu, Oct 10, 2024 at 04:27:56PM +0200, Amelie Delaunay wrote: > DMA3 maximum burst length (in unit of beat) may be restricted depending > on bus interconnect. > > As mentionned in STM32MP2 reference manual [1], "the maximum allowed AXI > burst length is 16. The user must set [S|D]BL_1 lower or equal to 15 > if the Source/Destination allocated port is AXI (if [S|D]AP=0)". This should be implied by the SoC specific compatible. > > Introduce st,axi-max-burst-len. If used, it will clamp the burst length > to that value if AXI port is used, if not, the maximum burst length value > supported by DMA3 is used. > > [1] https://www.st.com/resource/en/reference_manual/rm0457-stm32mp2325xx-advanced-armbased-3264bit-mpus-stmicroelectronics.pdf > > Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com> > --- > .../devicetree/bindings/dma/stm32/st,stm32-dma3.yaml | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml > index 38c30271f732e0c8da48199a224a88bb647eeca7..90ad70bb24eb790afe72bf2085478fa4cec60b94 100644 > --- a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml > +++ b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml > @@ -51,6 +51,16 @@ properties: > power-domains: > maxItems: 1 > > + st,axi-max-burst-len: > + description: | > + Restrict AXI burst length in unit of beat by value specified in this property. > + The value specified in this property is clamped to the maximum burst length supported by DMA3. > + If this property is missing, the maximum burst length supported by DMA3 is used. > + $ref: /schemas/types.yaml#/definitions/uint32 > + minimum: 1 > + maximum: 256 > + default: 64 > + > "#dma-cells": > const: 3 > description: | > @@ -137,5 +147,6 @@ examples: > <GIC_SPI 48 IRQ_TYPE_LEVEL_HIGH>; > clocks = <&rcc CK_BUS_HPDMA1>; > #dma-cells = <3>; > + st,axi-max-burst-len = <16>; > }; > ... > > -- > 2.25.1 >
On 10/10/24 20:16, Rob Herring wrote: > On Thu, Oct 10, 2024 at 04:27:56PM +0200, Amelie Delaunay wrote: >> DMA3 maximum burst length (in unit of beat) may be restricted depending >> on bus interconnect. >> >> As mentionned in STM32MP2 reference manual [1], "the maximum allowed AXI >> burst length is 16. The user must set [S|D]BL_1 lower or equal to 15 >> if the Source/Destination allocated port is AXI (if [S|D]AP=0)". > > This should be implied by the SoC specific compatible. > I took an example from snps,dw-axi-dmac.yaml (snps,axi-max-burst-len). But I agree, it will be implied by st,stm32mp25-dma3 compatible in V2. Patch 8/11 will then be dropped. Regards, Amelie >> >> Introduce st,axi-max-burst-len. If used, it will clamp the burst length >> to that value if AXI port is used, if not, the maximum burst length value >> supported by DMA3 is used. >> >> [1] https://www.st.com/resource/en/reference_manual/rm0457-stm32mp2325xx-advanced-armbased-3264bit-mpus-stmicroelectronics.pdf >> >> Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com> >> --- >> .../devicetree/bindings/dma/stm32/st,stm32-dma3.yaml | 11 +++++++++++ >> 1 file changed, 11 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml >> index 38c30271f732e0c8da48199a224a88bb647eeca7..90ad70bb24eb790afe72bf2085478fa4cec60b94 100644 >> --- a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml >> +++ b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml >> @@ -51,6 +51,16 @@ properties: >> power-domains: >> maxItems: 1 >> >> + st,axi-max-burst-len: >> + description: | >> + Restrict AXI burst length in unit of beat by value specified in this property. >> + The value specified in this property is clamped to the maximum burst length supported by DMA3. >> + If this property is missing, the maximum burst length supported by DMA3 is used. >> + $ref: /schemas/types.yaml#/definitions/uint32 >> + minimum: 1 >> + maximum: 256 >> + default: 64 >> + >> "#dma-cells": >> const: 3 >> description: | >> @@ -137,5 +147,6 @@ examples: >> <GIC_SPI 48 IRQ_TYPE_LEVEL_HIGH>; >> clocks = <&rcc CK_BUS_HPDMA1>; >> #dma-cells = <3>; >> + st,axi-max-burst-len = <16>; >> }; >> ... >> >> -- >> 2.25.1 >>
diff --git a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml index 38c30271f732e0c8da48199a224a88bb647eeca7..90ad70bb24eb790afe72bf2085478fa4cec60b94 100644 --- a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml +++ b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml @@ -51,6 +51,16 @@ properties: power-domains: maxItems: 1 + st,axi-max-burst-len: + description: | + Restrict AXI burst length in unit of beat by value specified in this property. + The value specified in this property is clamped to the maximum burst length supported by DMA3. + If this property is missing, the maximum burst length supported by DMA3 is used. + $ref: /schemas/types.yaml#/definitions/uint32 + minimum: 1 + maximum: 256 + default: 64 + "#dma-cells": const: 3 description: | @@ -137,5 +147,6 @@ examples: <GIC_SPI 48 IRQ_TYPE_LEVEL_HIGH>; clocks = <&rcc CK_BUS_HPDMA1>; #dma-cells = <3>; + st,axi-max-burst-len = <16>; }; ...
DMA3 maximum burst length (in unit of beat) may be restricted depending on bus interconnect. As mentionned in STM32MP2 reference manual [1], "the maximum allowed AXI burst length is 16. The user must set [S|D]BL_1 lower or equal to 15 if the Source/Destination allocated port is AXI (if [S|D]AP=0)". Introduce st,axi-max-burst-len. If used, it will clamp the burst length to that value if AXI port is used, if not, the maximum burst length value supported by DMA3 is used. [1] https://www.st.com/resource/en/reference_manual/rm0457-stm32mp2325xx-advanced-armbased-3264bit-mpus-stmicroelectronics.pdf Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com> --- .../devicetree/bindings/dma/stm32/st,stm32-dma3.yaml | 11 +++++++++++ 1 file changed, 11 insertions(+)