Re: [PATCH 5/6] common: kconfig: raise SYS_CBSIZE default to 1024 for FSL_LSCH2/LSCH3

On Mon, Aug 24, 2026 at 03:28:24PM +0300, Vladimir Oltean wrote:
>The 512-byte console input buffer limit for Layerscape SoCs originates
>from copy-pasted boilerplate in the original LS2085A board support added
>in commit f749db3a75ec ("ARMv8/ls2085a_emu: Add LS2085A emulator and
>simulator board support"). No rationale was given for the 512-byte
>choice; every subsequent FSL_LSCH2 and FSL_LSCH3 common header
>(ls1043a, ls1046a, ls1088a, lx2160a, ...) inherited it by convention.
>
>When CONFIG_SYS_CBSIZE was moved to Kconfig in commit d31466b382dd
>("Convert CONFIG_SYS_CBSIZE to Kconfig"), the existing 512-byte values
>were transcribed mechanically into Kconfig defaults, cementing the
>limit without re-examining its validity.
>
>The practical consequence is that environment variables holding
>multi-step boot scripts are silently truncated at 510 usable characters
>on all Layerscape boards, making it impossible to store commands such
>as combined TFTP+flash sequences in a single variable.
>
>The same problem was already identified and fixed for i.MX6 and i.MX7
>in commit f7b237b81e5a ("MLK-24380 imx6: Enlarge the console I/O buffer
nit:

This is a downstream commit.

Regards
Peng