The address bus on Agilex5 is limited to 40 bits. When SMMU is enable this
will cause address truncation and translation faults. Hence introducing
"altr,agilex5-axi-dma" to enable platform specific configuration to
configure the dma addressable bit mask.
Add a fallback capability for the compatible property to allow driver to
probe and initialize with a newly added compatible string without requiring
additional entry in the driver.
Signed-off-by: Khairul Anuar Romli <khairul.anuar.romli@altera.com>
---
.../devicetree/bindings/dma/snps,dw-axi-dmac.yaml | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)
diff --git a/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml b/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml
index a393a33c8908..db89ebf2b006 100644
--- a/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml
+++ b/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml
@@ -17,11 +17,15 @@ allOf:
properties:
compatible:
- enum:
- - snps,axi-dma-1.01a
- - intel,kmb-axi-dma
- - starfive,jh7110-axi-dma
- - starfive,jh8100-axi-dma
+ oneOf:
+ - enum:
+ - snps,axi-dma-1.01a
+ - intel,kmb-axi-dma
+ - starfive,jh7110-axi-dma
+ - starfive,jh8100-axi-dma
+ - items:
+ - const: altr,agilex5-axi-dma
+ - const: snps,axi-dma-1.01a
reg:
minItems: 1
--
2.43.7On Thu, Nov 20, 2025 at 07:31:10PM +0800, Khairul Anuar Romli wrote: > The address bus on Agilex5 is limited to 40 bits. When SMMU is enable this > will cause address truncation and translation faults. Hence introducing > "altr,agilex5-axi-dma" to enable platform specific configuration to > configure the dma addressable bit mask. That's likely a bus limitation, not an IP limitation. So that should be handled with dma-ranges. However, adding a specific compatible is perfectly fine. > > Add a fallback capability for the compatible property to allow driver to > probe and initialize with a newly added compatible string without requiring > additional entry in the driver. > > Signed-off-by: Khairul Anuar Romli <khairul.anuar.romli@altera.com> > --- > .../devicetree/bindings/dma/snps,dw-axi-dmac.yaml | 14 +++++++++----- > 1 file changed, 9 insertions(+), 5 deletions(-) > > diff --git a/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml b/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml > index a393a33c8908..db89ebf2b006 100644 > --- a/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml > +++ b/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml > @@ -17,11 +17,15 @@ allOf: > > properties: > compatible: > - enum: > - - snps,axi-dma-1.01a > - - intel,kmb-axi-dma > - - starfive,jh7110-axi-dma > - - starfive,jh8100-axi-dma > + oneOf: > + - enum: > + - snps,axi-dma-1.01a > + - intel,kmb-axi-dma > + - starfive,jh7110-axi-dma > + - starfive,jh8100-axi-dma > + - items: > + - const: altr,agilex5-axi-dma > + - const: snps,axi-dma-1.01a > > reg: > minItems: 1 > -- > 2.43.7 >
On 21/11/2025 1:36 am, Rob Herring wrote: > On Thu, Nov 20, 2025 at 07:31:10PM +0800, Khairul Anuar Romli wrote: >> The address bus on Agilex5 is limited to 40 bits. When SMMU is enable this >> will cause address truncation and translation faults. Hence introducing >> "altr,agilex5-axi-dma" to enable platform specific configuration to >> configure the dma addressable bit mask. > > That's likely a bus limitation, not an IP limitation. So that should be > handled with dma-ranges. > > However, adding a specific compatible is perfectly fine. > Would it be okay if I rephrase and send the next version with a correction in the commit message body as your comment in this version? Thanks. Regards, Khairul >> >> Add a fallback capability for the compatible property to allow driver to >> probe and initialize with a newly added compatible string without requiring >> additional entry in the driver. >> >> Signed-off-by: Khairul Anuar Romli <khairul.anuar.romli@altera.com> >> --- >> .../devicetree/bindings/dma/snps,dw-axi-dmac.yaml | 14 +++++++++----- >> 1 file changed, 9 insertions(+), 5 deletions(-) >> >> diff --git a/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml b/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml >> index a393a33c8908..db89ebf2b006 100644 >> --- a/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml >> +++ b/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml >> @@ -17,11 +17,15 @@ allOf: >> >> properties: >> compatible: >> - enum: >> - - snps,axi-dma-1.01a >> - - intel,kmb-axi-dma >> - - starfive,jh7110-axi-dma >> - - starfive,jh8100-axi-dma >> + oneOf: >> + - enum: >> + - snps,axi-dma-1.01a >> + - intel,kmb-axi-dma >> + - starfive,jh7110-axi-dma >> + - starfive,jh8100-axi-dma >> + - items: >> + - const: altr,agilex5-axi-dma >> + - const: snps,axi-dma-1.01a >> >> reg: >> minItems: 1 >> -- >> 2.43.7 >>
On Wed, Nov 26, 2025 at 07:43:42AM +0000, Romli, Khairul Anuar wrote: > On 21/11/2025 1:36 am, Rob Herring wrote: > > On Thu, Nov 20, 2025 at 07:31:10PM +0800, Khairul Anuar Romli wrote: > >> The address bus on Agilex5 is limited to 40 bits. When SMMU is enable this > >> will cause address truncation and translation faults. Hence introducing > >> "altr,agilex5-axi-dma" to enable platform specific configuration to > >> configure the dma addressable bit mask. > > > > That's likely a bus limitation, not an IP limitation. So that should be > > handled with dma-ranges. > > > > However, adding a specific compatible is perfectly fine. > > > Would it be okay if I rephrase and send the next version with a > correction in the commit message body as your comment in this version? Yes and your DTS patch might need changes - include proper dma-ranges. I also do not see how separate compatible without any driver change solved your case. That's a no-op patch from Linux driver point of view. See also submitting patches in DT dir about the process how patches are grouped together. Best regards, Krzysztof
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