Re: [PATCH AUTOSEL 5.8 20/20] riscv: Fix Kendryte K210 device tree

[Damien Le Moal]

On 2020/09/21 23:41, Sasha Levin wrote:
> From: Damien Le Moal <damien.lemoal@xxxxxxx>
> 
> [ Upstream commit f025d9d9934b84cd03b7796072d10686029c408e ]
> 
> The Kendryte K210 SoC CLINT is compatible with Sifive clint v0
> (sifive,clint0). Fix the Kendryte K210 device tree clint entry to be
> inline with the sifive timer definition documented in
> Documentation/devicetree/bindings/timer/sifive,clint.yaml.
> The device tree clint entry is renamed similarly to u-boot device tree
> definition to improve compatibility with u-boot defined device tree.
> To ensure correct initialization, the interrup-cells attribute is added
> and the interrupt-extended attribute definition fixed.
> 
> This fixes boot failures with Kendryte K210 SoC boards.
> 
> Note that the clock referenced is kept as K210_CLK_ACLK, which does not
> necessarilly match the clint MTIME increment rate. This however does not
> seem to cause any problem for now.
> 
> Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxx>
> Signed-off-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> ---
>  arch/riscv/boot/dts/kendryte/k210.dtsi | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/riscv/boot/dts/kendryte/k210.dtsi b/arch/riscv/boot/dts/kendryte/k210.dtsi
> index c1df56ccb8d55..d2d0ff6456325 100644
> --- a/arch/riscv/boot/dts/kendryte/k210.dtsi
> +++ b/arch/riscv/boot/dts/kendryte/k210.dtsi
> @@ -95,10 +95,12 @@ sysctl: sysctl@50440000 {
>  			#clock-cells = <1>;
>  		};
>  
> -		clint0: interrupt-controller@2000000 {
> +		clint0: clint@2000000 {
> +			#interrupt-cells = <1>;
>  			compatible = "riscv,clint0";
>  			reg = <0x2000000 0xC000>;
> -			interrupts-extended = <&cpu0_intc 3>,  <&cpu1_intc 3>;
> +			interrupts-extended =  <&cpu0_intc 3 &cpu0_intc 7
> +						&cpu1_intc 3 &cpu1_intc 7>;
>  			clocks = <&sysctl K210_CLK_ACLK>;
>  		};
>  
> 

Sasha,

This is a fix for a problem in 5.9 tree. 5.8 kernel is fine without this patch.
And I think applying it to 5.8 might actually break things since the proper
clint driver was added to kernel 5.9 and does not exist in 5.8.

Best regards.

-- 
Damien Le Moal
Western Digital Research