[PATCH] at91: sam9x5 dt: add usart dma definitions to dt

[Ludovic Desroches]

Hi,

On Fri, Oct 10, 2014 at 08:35:56AM +0200, Jiri Prchal wrote:
> This patch adds usart dma definitions to both dtsi for sam9x5 chips. Without
> usage of dma it's unable to catch all bytes on usart receiver.
> 

Adding DMA configuration is a good idea. But I think we will have an
issue because we have too many requested channels for DMA0.

Adding usart0, 9 dma channels will be requested. So a choice has to be
done. On DMA0 we have:
- 2 channels for SSC,
- 1 channel for MMC,
- 2 channels for I2C0,
- 2 channels for SPI0,
- 2 channels for USART0.

I have only mentionned enabled devices.

Regards

Ludovic


> Signed-off-by: Jiri Prchal <jiri.prchal at aksignal.cz>
> ---
>  arch/arm/boot/dts/at91sam9x5.dtsi        | 20 ++++++++++++++++++++
>  arch/arm/boot/dts/at91sam9x5_usart3.dtsi |  5 +++++
>  2 files changed, 25 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/at91sam9x5.dtsi b/arch/arm/boot/dts/at91sam9x5.dtsi
> index 726274f..f9acf6d 100644
> --- a/arch/arm/boot/dts/at91sam9x5.dtsi
> +++ b/arch/arm/boot/dts/at91sam9x5.dtsi
> @@ -860,6 +860,11 @@
>  				interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
>  				pinctrl-names = "default";
>  				pinctrl-0 = <&pinctrl_dbgu>;
> +				atmel,use-dma-tx;
> +				atmel,use-dma-rx;
> +				dmas = <&dma1 1 AT91_DMA_CFG_PER_ID(8)>,
> +				       <&dma1 1 (AT91_DMA_CFG_PER_ID(9) | AT91_DMA_CFG_FIFOCFG_ASAP)>;
> +				dma-names = "tx", "rx";
>  				clocks = <&mck>;
>  				clock-names = "usart";
>  				status = "disabled";
> @@ -871,6 +876,11 @@
>  				interrupts = <5 IRQ_TYPE_LEVEL_HIGH 5>;
>  				pinctrl-names = "default";
>  				pinctrl-0 = <&pinctrl_usart0>;
> +				atmel,use-dma-rx;
> +				atmel,use-dma-tx;
> +				dmas = <&dma0 1 AT91_DMA_CFG_PER_ID(3)>,
> +				       <&dma0 1 (AT91_DMA_CFG_PER_ID(4) | AT91_DMA_CFG_FIFOCFG_ASAP)>;
> +				dma-names = "tx", "rx";
>  				clocks = <&usart0_clk>;
>  				clock-names = "usart";
>  				status = "disabled";
> @@ -882,6 +892,11 @@
>  				interrupts = <6 IRQ_TYPE_LEVEL_HIGH 5>;
>  				pinctrl-names = "default";
>  				pinctrl-0 = <&pinctrl_usart1>;
> +				atmel,use-dma-rx;
> +				atmel,use-dma-tx;
> +				dmas = <&dma0 1 AT91_DMA_CFG_PER_ID(5)>,
> +				       <&dma0 1 (AT91_DMA_CFG_PER_ID(6) | AT91_DMA_CFG_FIFOCFG_ASAP)>;
> +				dma-names = "tx", "rx";
>  				clocks = <&usart1_clk>;
>  				clock-names = "usart";
>  				status = "disabled";
> @@ -893,6 +908,11 @@
>  				interrupts = <7 IRQ_TYPE_LEVEL_HIGH 5>;
>  				pinctrl-names = "default";
>  				pinctrl-0 = <&pinctrl_usart2>;
> +				atmel,use-dma-rx;
> +				atmel,use-dma-tx;
> +				dmas = <&dma1 1 AT91_DMA_CFG_PER_ID(12)>,
> +				       <&dma1 1 (AT91_DMA_CFG_PER_ID(13) | AT91_DMA_CFG_FIFOCFG_ASAP)>;
> +				dma-names = "tx", "rx";
>  				clocks = <&usart2_clk>;
>  				clock-names = "usart";
>  				status = "disabled";
> diff --git a/arch/arm/boot/dts/at91sam9x5_usart3.dtsi b/arch/arm/boot/dts/at91sam9x5_usart3.dtsi
> index 140217a5..731da0e 100644
> --- a/arch/arm/boot/dts/at91sam9x5_usart3.dtsi
> +++ b/arch/arm/boot/dts/at91sam9x5_usart3.dtsi
> @@ -57,6 +57,11 @@
>  				interrupts = <8 IRQ_TYPE_LEVEL_HIGH 5>;
>  				pinctrl-names = "default";
>  				pinctrl-0 = <&pinctrl_usart3>;
> +				atmel,use-dma-rx;
> +				atmel,use-dma-tx;
> +				dmas = <&dma1 1 AT91_DMA_CFG_PER_ID(14)>,
> +				       <&dma1 1 (AT91_DMA_CFG_PER_ID(15) | AT91_DMA_CFG_FIFOCFG_ASAP)>;
> +				dma-names = "tx", "rx";
>  				clocks = <&usart3_clk>;
>  				clock-names = "usart";
>  				status = "disabled";
> --
> 1.9.1
> 
> 
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