Re: [PATCH] riscv: dts: sophgo: reduce SG2042 MSI count to 16

[Chen Wang <unicorn_wang@outlook.com>]

On 4/8/2026 12:01 AM, Icenowy Zheng wrote:
> The SG2042 MSI controller has one 32-bit doorbell register, and each bit
> corresponds to an interrupt. At a glance, it seems that the MSI
> controller can support 32 interrupts; however the PCI MSI capability
> only supports 16-bit messages, which makes the high 16 interrupts
> unusable in such way.
>
> Reduce the MSI count to 16 to prevent producing MSI message values that
> cannot fit 16-bit integers.
>
> Signed-off-by: Icenowy Zheng <zhengxingda@iscas.ac.cn>
> ---
>   arch/riscv/boot/dts/sophgo/sg2042.dtsi | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/riscv/boot/dts/sophgo/sg2042.dtsi b/arch/riscv/boot/dts/sophgo/sg2042.dtsi
> index 9fddf3f0b3b99..9f1820a7b5a9f 100644
> --- a/arch/riscv/boot/dts/sophgo/sg2042.dtsi
> +++ b/arch/riscv/boot/dts/sophgo/sg2042.dtsi
> @@ -234,7 +234,7 @@ msi: msi-controller@7030010304 {
>   			reg-names = "clr", "doorbell";
>   			msi-controller;
>   			#msi-cells = <0>;
> -			msi-ranges = <&intc 64 IRQ_TYPE_EDGE_RISING 32>;
> +			msi-ranges = <&intc 64 IRQ_TYPE_EDGE_RISING 16>;
>   		};
>   
>   		rpgate: clock-controller@7030010368 {

LGTM.

Reviewed-by: Chen Wang <unicorn_wang@outlook.com>

Tested-by: Chen Wang <unicorn_wang@outlook.com> on Pioneerbox.

Thanks,

Chen


Hi, Han,

Will you please run some quick test on EVB boards, I have no such 
hardware in hand, thanks.