+/* The current supported ISA spec versions. */
+
+enum riscv_isa_spec_class
+{
+ ISA_SPEC_CLASS_NONE,
+
+ ISA_SPEC_CLASS_2P2,
+ ISA_SPEC_CLASS_20190608,
+ ISA_SPEC_CLASS_20191213
+};
+
+/* This structure holds version information for specific ISA. */
+
+struct riscv_ext_version
+{
+ const char *name;
+ enum riscv_isa_spec_class isa_spec_class;
+ unsigned int major_version;
+ unsigned int minor_version;
+};
+
+/* All RISC-V CSR belong to one of these classes. */
+
+enum riscv_csr_class
+{
+ CSR_CLASS_NONE,
+
+ CSR_CLASS_I,
+ CSR_CLASS_I_32, /* rv32 only */
+ CSR_CLASS_F, /* f-ext only */
+};
+
+/* The current supported privilege spec versions. */
+
+enum riscv_priv_spec_class
+{
+ PRIV_SPEC_CLASS_NONE,
+
+ PRIV_SPEC_CLASS_1P9,
+ PRIV_SPEC_CLASS_1P9P1,
+ PRIV_SPEC_CLASS_1P10,
+ PRIV_SPEC_CLASS_1P11,
+ PRIV_SPEC_CLASS_DRAFT
+};
+
+/* This structure holds all restricted conditions for a CSR. */
+
+struct riscv_csr_extra
+{
+ /* Class to which this CSR belongs. Used to decide whether or
+ not this CSR is legal in the current -march context. */
+ enum riscv_csr_class csr_class;
+
+ /* CSR may have differnet numbers in the previous priv spec. */
+ unsigned address;
+
+ /* Record the CSR is defined/valid in which versions. */
+ enum riscv_priv_spec_class define_version;
+
+ /* Record the CSR is aborted/invalid from which versions. If it isn't
+ aborted in the current version, then it should be CSR_CLASS_VDRAFT. */
+ enum riscv_priv_spec_class abort_version;
+
+ /* The CSR may have more than one setting. */
+ struct riscv_csr_extra *next;
+};
+