Re: [PATCH v2 1/4] riscv: dts: Update memory configuration

[Conor Dooley <conor@kernel.org>]

On Fri, Oct 21, 2022 at 12:29:19PM +0530, Padmarao Begari wrote:
> In the v2022.10 Icicle reference design, the seg registers are going to be

Hey Padmarao,
Since the release was done the other day I think that this should be
s/are going to be/have been

> changed, resulting in a required change to the memory map.
> A small 4MB reservation is made at the end of 32-bit DDR to provide some
> memory for the HSS to use, so that it can cache its payload between
> reboots of a specific context.
> 
> Co-developed-by: Conor Dooley <conor.dooley@microchip.com>
> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
> Signed-off-by: Padmarao Begari <padmarao.begari@microchip.com>
> Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
> ---
>  arch/riscv/dts/microchip-mpfs-icicle-kit.dts | 70 ++++----------------
>  1 file changed, 14 insertions(+), 56 deletions(-)
> 
> diff --git a/arch/riscv/dts/microchip-mpfs-icicle-kit.dts b/arch/riscv/dts/microchip-mpfs-icicle-kit.dts
> index 287ef3d23b..876c475069 100644
> --- a/arch/riscv/dts/microchip-mpfs-icicle-kit.dts
> +++ b/arch/riscv/dts/microchip-mpfs-icicle-kit.dts
> @@ -1,6 +1,6 @@
>  // SPDX-License-Identifier: (GPL-2.0+ OR MIT)
>  /*
> - * Copyright (C) 2021 Microchip Technology Inc.
> + * Copyright (C) 2021-2022 Microchip Technology Inc.
>   * Padmarao Begari <padmarao.begari@microchip.com>
>   */
>  
> @@ -28,70 +28,28 @@
>  		timebase-frequency = <RTCCLK_FREQ>;
>  	};

FWIW I think we should add the compatible that the linux dt has,
signifying that this memory layout is compatible with the v2022.10
release and later (w/ appropriate line-wrapping ofc):
compatible = "microchip,mpfs-icicle-reference-rtlv2210", "microchip,mpfs-icicle-kit", "microchip,mpfs";

Other than that:
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>

>  
> -	reserved-memory {
> -		ranges;
> -		#size-cells = <2>;
> -		#address-cells = <2>;
> -
> -		fabricbuf0: fabricbuf@0 {
> -			compatible = "shared-dma-pool";
> -			reg = <0x0 0xae000000 0x0 0x2000000>;
> -			label = "fabricbuf0-ddr-c";
> -		};
> -
> -		fabricbuf1: fabricbuf@1 {
> -			compatible = "shared-dma-pool";
> -			reg = <0x0 0xc0000000 0x0 0x8000000>;
> -			label = "fabricbuf1-ddr-nc";
> -		};
> -
> -		fabricbuf2: fabricbuf@2 {
> -			compatible = "shared-dma-pool";
> -			reg = <0x0 0xd8000000 0x0 0x8000000>;
> -			label = "fabricbuf2-ddr-nc-wcb";
> -		};
> -	};
> -
> -	udmabuf0 {
> -		compatible = "ikwzm,u-dma-buf";
> -		device-name = "udmabuf-ddr-c0";
> -		minor-number = <0>;
> -		size = <0x0 0x2000000>;
> -		memory-region = <&fabricbuf0>;
> -		sync-mode = <3>;
> -	};
> -
> -	udmabuf1 {
> -		compatible = "ikwzm,u-dma-buf";
> -		device-name = "udmabuf-ddr-nc0";
> -		minor-number = <1>;
> -		size = <0x0 0x8000000>;
> -		memory-region = <&fabricbuf1>;
> -		sync-mode = <3>;
> -	};
> -
> -	udmabuf2 {
> -		compatible = "ikwzm,u-dma-buf";
> -		device-name = "udmabuf-ddr-nc-wcb0";
> -		minor-number = <2>;
> -		size = <0x0 0x8000000>;
> -		memory-region = <&fabricbuf2>;
> -		sync-mode = <3>;
> -	};
> -
>  	ddrc_cache_lo: memory@80000000 {
>  		device_type = "memory";
> -		reg = <0x0 0x80000000 0x0 0x2e000000>;
> -		clocks = <&clkcfg CLK_DDRC>;
> +		reg = <0x0 0x80000000 0x0 0x40000000>;
>  		status = "okay";
>  	};
>  
>  	ddrc_cache_hi: memory@1000000000 {
>  		device_type = "memory";
> -		reg = <0x10 0x0 0x0 0x40000000>;
> -		clocks = <&clkcfg CLK_DDRC>;
> +		reg = <0x10 0x40000000 0x0 0x40000000>;
>  		status = "okay";
>  	};
> +
> +	reserved-memory {
> +		#address-cells = <2>;
> +		#size-cells = <2>;
> +		ranges;
> +
> +		hss_payload: region@BFC00000 {
> +			reg = <0x0 0xBFC00000 0x0 0x400000>;
> +			no-map;
> +		};
> +	};
>  };
>  
>  &uart1 {
> -- 
> 2.25.1
>