Add LW instruction

This commit is contained in:
Donald Sebastian Leung 2020-07-31 16:27:36 +08:00
parent 96015ee5d9
commit dc31087f73
1 changed files with 25 additions and 0 deletions

25
insns/insn_lw.py Normal file
View File

@ -0,0 +1,25 @@
from insn_I import *
class rvfi_insn_lw(rvfi_insn_I):
def __init__(self):
super(rvfi_insn_lw, self).__init__()
def ports(self):
return super(rvfi_insn_lw, self).ports()
def elaborate(self, platform):
m = super(rvfi_insn_lw, self).elaborate(platform)
# LW instruction
addr = Signal(32)
m.d.comb += addr.eq(self.rvfi_rs1_rdata + self.insn_imm)
result = Signal(32)
m.d.comb += result.eq(self.rvfi_mem_rdata)
m.d.comb += self.spec_valid.eq(self.rvfi_valid & (self.insn_funct3 == 0b010) & (self.insn_opcode == 0b0000011))
m.d.comb += self.spec_rs1_addr.eq(self.insn_rs1)
m.d.comb += self.spec_rd_addr.eq(self.insn_rd)
m.d.comb += self.spec_mem_addr.eq(addr)
m.d.comb += self.spec_mem_rmask.eq((1 << 4) - 1)
m.d.comb += self.spec_rd_wdata.eq(Mux(self.spec_rd_addr, Value.as_signed(result), 0))
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