17. RISC-V Specific Information¶
17.1. Calling Conventions¶
Please refer to the RISC-V ELF psABI specification.
17.2. Multilibs¶
The GCC for RISC-V can generate code for several 32-bit and 64-bit ISA/ABI variants. The following multilibs are available:
.: The default multilib ISA is RV32IMAFDC with ABI ILP32D.rv32i/ilp32: ISA RV32I with ABI ILP32.rv32im/ilp32: ISA RV32IM with ABI ILP32.rv32imafd/ilp32d: ISA RV32IMAFD with ABI ILP32D.rv32iac/ilp32: ISA RV32IAC with ABI ILP32.rv32imac/ilp32: ISA RV32IMAC with ABI ILP32.rv32imafc/ilp32f: ISA RV32IMAFC with ABI ILP32F.rv64imafd/lp64d: ISA RV64IMAFD with ABI LP64D and code model medlow.rv64imafd/lp64d/medany: ISA RV64IMAFD with ABI LP64D and code model medany.rv64imac/lp64: ISA RV64IMAC with ABI LP64 and code model medlow.rv64imac/lp64/medany: ISA RV64IMAC with ABI LP64 and code model medany.rv64imafdc/lp64d: ISA RV64IMAFDC with ABI LP64D and code model medlow.rv64imafdc/lp64d/medany: ISA RV64IMAFDC with ABI LP64D and code model medany.
17.3. Interrupt Processing¶
Interrupt exceptions are handled via the interrupt extensions API. All other exceptions end up in a fatal error (RTEMS_FATAL_SOURCE_EXCEPTION).
17.3.1. Interrupt Levels¶
There are exactly two interrupt levels on RISC-V with respect to RTEMS. Level zero corresponds to machine interrupts enabled. Level one corresponds to machine interrupts disabled.
17.3.2. Interrupt Stack¶
The memory region for the interrupt stack is defined by the BSP.
17.4. Symmetric Multiprocessing¶
SMP is supported.
17.5. Thread-Local Storage¶
Thread-local storage is supported.