SystemVerilog Bindings¶

ml-hpi produces two distinct SystemVerilog outputs from a single spec:

Interface class declarations (GenSVInterface) – the SV-native hierarchical API.
DPI glue package (GenSV) – a flat DPI bridge that lets C code call into the SV interface hierarchy.

This page documents both.

Interface Class Generator¶

GenSVInterface emits one .sv file per package containing interface class declarations. Each ml-hpi interface becomes a SystemVerilog interface class; methods become pure virtual function or pure virtual task declarations; members become accessor methods.

Generated Artifacts¶

For a spec whose interfaces share the package prefix pkg, the generator produces pkg.sv:

$ python -m ml_hpi generate --spec spec.yaml --outdir gen/ --lang sv

Output structure:

package pkg;
  interface class RegIf;
    pure virtual task write32(longint unsigned addr, int unsigned data);
    pure virtual task read32(output int unsigned rval, input longint unsigned addr);
    pure virtual function void reset();
  endclass

  interface class BusIf;
    pure virtual function RegIf regs();
    pure virtual function RegIf ports_at(int idx);
    pure virtual function int ports_size();
  endclass

  interface class ExtRegIf extends RegIf;
    pure virtual function void configure(int unsigned mode);
  endclass
endpackage

Method Mapping¶

ml-hpi construct	SystemVerilog output
Method (non-blocking)	`pure virtual function {rtype} {name}({params});`
Method (blocking, void return)	`pure virtual task {name}({params});`
Method (blocking, non-void return)	`pure virtual task {name}(output {rtype} rval, input {params});`
Member (field)	`pure virtual function {IfType} {name}();`
Member (array)	`pure virtual function {IfType} {name}_at(int idx);` `pure virtual function int {name}_size();`
Inheritance	`interface class Derived extends Base;`

Type Mapping¶

ml-hpi	SystemVerilog
`void`	`void`
`bool`	`bit`
`int8`	`byte`
`uint8`	`byte unsigned`
`int16`	`shortint`
`uint16`	`shortint unsigned`
`int32`	`int`
`uint32`	`int unsigned`
`int64`	`longint`
`uint64`	`longint unsigned`
`addr` / `addr32`	`int unsigned`
`addr` / `addr64`	`longint unsigned`
`uintptr`	`chandle`

DPI Glue Generator¶

GenSV produces a DPI bridge package that allows C code to invoke SV interface methods through the DPI-C mechanism. It emits a root registry class, a navigate() function, and DPI export wrappers.

This generator requires a --root-if argument identifying the root interface of the hierarchy:

$ python -m ml_hpi generate --spec spec.yaml --outdir gen/ --lang sv \
    --root-if pkg.RegIf

See the C bindings page for the matching C header.

SV Parser¶

ParseSV uses pyslang to parse interface class declarations back to an MlHpiDoc.

$ python -m ml_hpi parse --lang sv --input pkg.sv --output recovered.yaml

Limitations:

target / solve attributes are not expressible in SV interface class syntax and default to unset in the parsed output. Add // ml-hpi:target=true pragma comments to preserve them.
addr64 vs uint64 ambiguity: the parser defaults to uint64.
pyslang is a hard requirement; no fallback parser is provided.