[S] Change in coreboot[main]: arch/riscv/payload: Replace old RISC-V CSR names with their values

[Maximilian Brune (Code Review)]

Attention is currently required from: Philipp Hug, Zebreus, ron minnich.

Maximilian Brune has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/79364?usp=email )

Change subject: arch/riscv/payload: Replace old RISC-V CSR names with their values
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Patch Set 3:

(1 comment)

File src/arch/riscv/payload.c:

https://review.coreboot.org/c/coreboot/+/79364/comment/1082f13f_f4c88c44 :
PS3, Line 49: 		write_csr(0x0004, 0);
I would just remove the code altogether.
Like you said its not part of the RISC-V ISA Manual Privileged Specification anymore and as far as I know it is also not part of any other ratified extension.
It is not used by any code in coreboot and will therefore not break anything.
Also I would like to avoid using CSRs that are not part of the base specification inside architecture code. If there is a use case for a platform in coreboot that needs this (maybe M-U mode only platforms?) we can worry about it then.