Re: [PATCH v5 03/13] dt-bindings: dma: dw-axi-dmac: extend the number of interrupts

Ben Dooks
2022-07-18T15:56:52Z

On 05/07/2022 22:52, Conor Dooley wrote:
> From: Conor Dooley <conor.dooley@microchip.com>
>
> The Canaan k210 apparently has a Sysnopsys Designware AXI DMA
> controller, but according to the documentation & devicetree it has 6
> interrupts rather than the standard one. Support the 6 interrupt
> configuration by unconditionally extending the binding to a maximum of
> 8 per-channel interrupts thereby matching the number of possible
> channels.

I think you can still configure it to produce a single interrupt
even if there are per-channel interrupts available. This is from
my reading of the driver a little while ago so may not be totally
correct now.

Having per-channel irqs might be useful in the future, but as above
I think it'll require the driver to be updated to do it (and possibly
some sort of detection)

> Link: https://canaan-creative.com/wp-content/uploads/2020/03/kendryte_standalone_programming_guide_20190311144158_en.pdf #Page 51
> Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
> Reviewed-by: Rob Herring <robh@kernel.org>
> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
> ---
> .../devicetree/bindings/dma/snps,dw-axi-dmac.yaml | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml b/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml
> index 4324a94b26b2..67aa7bb6d36a 100644
> --- a/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml
> +++ b/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml
> @@ -34,7 +34,12 @@ properties:
> - const: axidma_apb_regs
>
> interrupts:
> - maxItems: 1
> + description:
> + If the IP-core synthesis parameter DMAX_INTR_IO_TYPE is set to 1, this
> + will be per-channel interrupts. Otherwise, this is a single combined IRQ
> + for all channels.
> + minItems: 1
> + maxItems: 8
>
> clocks:
> items:

--
Ben Dooks http://www.codethink.co.uk/
Senior Engineer Codethink - Providing Genius