RISC-V Design · All levels
IOMMU Translation and the DMA Memory View: Software and Programmer View
Software and Programmer View for IOMMU Translation and the DMA Memory View.
Software and programmer view
Software and Programmer View for IOMMU Translation and the DMA Memory View is anchored on DMA translation fault rate, device-TLB miss latency, and end-to-end I/O bandwidth impact with isolation enabled.. Convert observations into mechanism-backed decisions with explicit ownership.
Keep ISA profile, ABI, and extension assumptions explicit.
Validate runtime feature detection against hardware contract.
Correlate compiler output with microarchitectural counters.
Preserve deterministic trap and privilege behavior in all modes.
Decode contract
diagram
DECODE CONTROL MAP - IOMMU Translation and the DMA Memory View
opcode/funct3/funct7 controls asserted
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LUI / AUIPC rd_write, imm_select(U), alu_add_pc
JAL / JALR rd_write, pc_redirect, link_write
BRANCH cmp_enable, branch_type, pc_redirect
LOAD mem_read, rd_write, wb_sel(memory)
STORE mem_write, store_size, addr_calc
OP-IMM alu_enable, imm_select(I), rd_write
OP alu_enable, src2_reg, rd_write
SYSTEM / CSR csr_readwrite, trap_check, privilege_gate
VECTOR (V extension) vdecode, lane_mask, vtype_update