core: riscv: Fix initial value of a0 in "detect_csr" ASM macro

To set initial value of the register a0 to 1, the assembly code should
be "li a0, 1" instead of "addi a0, a0, 1".

Signed-off-by: Alvin

core: riscv: Fix initial value of a0 in "detect_csr" ASM macro

To set initial value of the register a0 to 1, the assembly code should
be "li a0, 1" instead of "addi a0, a0, 1".

Signed-off-by: Alvin Chang <alvinga@andestech.com>
Reviewed-by: Yu-Chien Peter Lin <peterlin@andestech.com>
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>

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core: riscv: Add seed CSR detection helper

Any attempted access to unimplemented or restricted CSRs will
raise an illegal instruction, so we can set up a temporary
trap handler to validate if the us

core: riscv: Add seed CSR detection helper

Any attempted access to unimplemented or restricted CSRs will
raise an illegal instruction, so we can set up a temporary
trap handler to validate if the use of CSRs is allowed in
the privileged mode where OP-TEE OS is running. Add a helper
for this specific purpose.

Signed-off-by: Alvin Chang <alvinga@andestech.com>
Reviewed-by: Yu Chien Peter Lin <peterlin@andestech.com>
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>

show more ...