From 0f71c1dad106802865bea370b8a0ec801f4f0693 Mon Sep 17 00:00:00 2001 From: Donald Sebastian Leung Date: Tue, 11 Aug 2020 14:00:04 +0800 Subject: [PATCH] Add RV32I S-Type Instruction Format --- insns/InsnRV32ISType.py | 46 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 insns/InsnRV32ISType.py diff --git a/insns/InsnRV32ISType.py b/insns/InsnRV32ISType.py new file mode 100644 index 0000000..089173f --- /dev/null +++ b/insns/InsnRV32ISType.py @@ -0,0 +1,46 @@ +from Insn import * + +""" +RV32I S-Type Instruction +""" + +class InsnRV32ISType(Insn): + def __init__(self, RISCV_FORMAL_ILEN, RISCV_FORMAL_XLEN, RISCV_FORMAL_CSR_MISA, RISCV_FORMAL_COMPRESSED, RISCV_FORMAL_ALIGNED_MEM, funct3, mask_shift): + super().__init__(RISCV_FORMAL_ILEN, RISCV_FORMAL_XLEN, RISCV_FORMAL_CSR_MISA, RISCV_FORMAL_COMPRESSED) + self.RISCV_FORMAL_ALIGNED_MEM = RISCV_FORMAL_ALIGNED_MEM + self.funct3 = funct3 + self.mask_shift = mask_shift + self.addr = Signal(self.RISCV_FORMAL_XLEN) + def elaborate(self, platform): + m = super().elaborate(platform) + + m.d.comb += self.insn_imm.eq(Value.as_signed(Cat(self.rvfi_insn[7:12], self.rvfi_insn[25:32]))) + + if self.RISCV_FORMAL_CSR_MISA: + m.d.comb += self.misa_ok.eq((self.rvfi_csr_misa_rdata & 0) == 0) + m.d.comb += self.spec_csr_misa_rmask.eq(0) + else: + m.d.comb += self.misa_ok.eq(1) + + if self.RISCV_FORMAL_ALIGNED_MEM: + m.d.comb += self.addr.eq(self.rvfi_rs1_rdata + self.insn_imm) + m.d.comb += self.spec_valid.eq(self.rvfi_valid & (~self.insn_padding) & (self.insn_funct3 == self.funct3) & (self.insn_opcode == 0b0100011)) + m.d.comb += self.spec_rs1_addr.eq(self.insn_rs1) + m.d.comb += self.spec_rs2_addr.eq(self.insn_rs2) + m.d.comb += self.spec_mem_addr.eq(self.addr & ~(int(self.RISCV_FORMAL_XLEN // 8) - 1)) + m.d.comb += self.spec_mem_wmask.eq(((1 << self.mask_shift) - 1) << (self.addr - self.spec_mem_addr)) + m.d.comb += self.spec_mem_wdata.eq(self.rvfi_rs2_rdata << (8 * (self.addr - self.spec_mem_addr))) + m.d.comb += self.spec_pc_wdata.eq(self.rvfi_pc_rdata + 4) + m.d.comb += self.spec_trap.eq(((self.addr & (self.mask_shift - 1)) != 0) | ~self.misa_ok) + else: + m.d.comb += self.addr.eq(self.rvfi_rs1_rdata + self.insn_imm) + m.d.comb += self.spec_valid.eq(self.rvfi_valid & (~self.insn_padding) & (self.insn_funct3 == self.funct3) & (self.insn_opcode == 0b0100011)) + m.d.comb += self.spec_rs1_addr.eq(self.insn_rs1) + m.d.comb += self.spec_rs2_addr.eq(self.insn_rs2) + m.d.comb += self.spec_mem_addr.eq(self.addr) + m.d.comb += self.spec_mem_wmask.eq((1 << self.mask_shift) - 1) + m.d.comb += self.spec_mem_wdata.eq(self.rvfi_rs2_rdata) + m.d.comb += self.spec_pc_wdata.eq(self.rvfi_pc_rdata + 4) + m.d.comb += self.spec_trap.eq(~self.misa_ok) + + return m