Up to now the SBI specification does not define how unsupported EIDs and
FIDs shall be handled. Require returning error code SBI_ERR_NOT_SUPPORTED.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@...>
=2D--
riscv-sbi.adoc | 3 +++
1 file changed, 3 insertions(+)

diff --git a/riscv-sbi.adoc b/riscv-sbi.adoc
index d7401fa..262248f 100644
=2D-- a/riscv-sbi.adoc
+++ b/riscv-sbi.adoc
@@ -112,6 +112,9 @@ Standard SBI error codes are listed below
| SBI_ERR_ALREADY_AVAILABLE | -6
|=3D=3D=3D

+An `ECALL` with an unsupported SBI extension ID (*EID*) or an unsupported=
SBI
+function ID (*FID*) must return the error code `SBI_ERR_NOT_SUPPORTED`.
+
Every SBI function should prefer `unsigned long` as the data type. It kee=
ps
the specification simple and easily adaptable for all RISC-V ISA types (i=
.e.
RV32, RV64 and RV128). In case the data is defined as 32bit wide, higher
=2D-
2.30.1