"Zicsr" isa extension has been separated from "I" extension.
This patch add the isa requirement of "Zicsr" extension in
platform requirements documentation.
Signed-off-by: Yangjie Zhang <jay1273062855@outlook.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
The base RISC-V platform requirements for OpenSBI are as follows:
-1. At least rv32ima or rv64ima required on all HARTs
+1. At least rv32ima_zicsr or rv64ima_zicsr required on all HARTs
2. At least one HART should have S-mode support because:
* SBI calls are meant for RISC-V S-mode (Supervisor mode)
6. Hardware support for injecting M-mode software interrupts on
a multi-HART platform
-The RISC-V extensions not covered by rv32ima or rv64ima are optional
+The RISC-V extensions not covered by rv32ima_zicsr or rv64ima_zicsr are optional
for OpenSBI. Although, OpenSBI will detect and handle some of these
optional RISC-V extensions at runtime.