[OpenWrt-Devel] [PATCH 2/3] ath79: add support for Netgear WNDR4300 v2

David Bauer mail at david-bauer.net
Sat Dec 21 11:52:18 EST 2019


Hello Michal,

On 12/21/19 2:54 PM, Michal Cieslakiewicz wrote:
> 1. NAND Flash (128 MiB) layout under OpenWrt is changed as follows:
>    all space is assigned to 'firmware' partition which is divided into
>    2 MiB kernel and 126 MiB UBI areas; vendor partitions (language and
>    mtdoops) are removed; kernel space size can be increased if needed;
>    maximum image size is set to 25600k for compatibility and can also
>    be increased.

Do you know if there is a hard limit to the kernel size? OpenWrt does not support
relocation of UBI as doing so would interfere with wear leveling.
This means the kernel size is more or less fixed if we want to be able to use sysupgrade.

I personally would prefer to allocate 4 (or even 8) megabytes to the kernel partition.
This would give us a lot more flexibility (ath79 kernel is already at ~1.8MB the last time
I've checked.

> +	flash at 1 {
> +		compatible = "spi-nand";
> +		reg = <1>;
> +		spi-max-frequency = <25000000>;
> +
> +		partitions {
> +			compatible = "fixed-partitions";
> +			#address-cells = <1>;
> +			#size-cells = <1>;
> +
> +			partition at 0 {
> +				label = "firmware";
> +				reg = <0x0 0x8000000>;
> +				compatible = "netgear,uimage";
> +			};
> +
> +			kernel at 0 {
> +				label = "kernel";
> +				reg = <0x0 0x200000>;
> +			};
> +
> +			ubi at 200000 {
> +				label = "ubi";
> +				reg = <0x200000 0x7e00000>;
> +			};
> +		};
> +	};

The firmware node can be dropped, as kernel and UBI partitions are fixed.

Best wishes
David

_______________________________________________
openwrt-devel mailing list
openwrt-devel at lists.openwrt.org
https://lists.openwrt.org/mailman/listinfo/openwrt-devel



More information about the openwrt-devel mailing list