Add taxi apb interface

src/peakrdl_busdecoder/__peakrdl__.py

@@ -5,7 +5,7 @@ from peakrdl.config import schema
 from peakrdl.plugins.entry_points import get_entry_points
 from peakrdl.plugins.exporter import ExporterSubcommandPlugin
 
-from .cpuif import BaseCpuif, apb3, apb4, axi4lite
+from .cpuif import BaseCpuif, apb3, apb4, axi4lite, taxi_apb
 from .exporter import BusDecoderExporter
 from .udps import ALL_UDPS
 
@@ -24,6 +24,7 @@ def get_cpuifs(config: list[tuple[str, Any]]) -> dict[str, type[BaseCpuif]]:
         "apb3-flat": apb3.APB3CpuifFlat,
         "apb4": apb4.APB4Cpuif,
         "apb4-flat": apb4.APB4CpuifFlat,
+        "taxi-apb": taxi_apb.TaxiAPBCpuif,
         "axi4-lite": axi4lite.AXI4LiteCpuif,
         "axi4-lite-flat": axi4lite.AXI4LiteCpuifFlat,
     }

src/peakrdl_busdecoder/cpuif/interface.py

@@ -64,17 +64,20 @@ class Interface(ABC):
 class SVInterface(Interface):
     """SystemVerilog interface-based signal handling."""
 
+    slave_modport_name = "slave"
+    master_modport_name = "master"
+
     @property
     def is_interface(self) -> bool:
         return True
 
     def get_port_declaration(self, slave_name: str, master_prefix: str) -> str:
         """Generate SystemVerilog interface port declarations."""
-        slave_ports: list[str] = [f"{self.get_interface_type()}.slave {slave_name}"]
+        slave_ports: list[str] = [f"{self.get_interface_type()}.{self.slave_modport_name} {slave_name}"]
         master_ports: list[str] = []
 
         for child in self.cpuif.addressable_children:
-            base = f"{self.get_interface_type()}.master {master_prefix}{child.inst_name}"
+            base = f"{self.get_interface_type()}.{self.master_modport_name} {master_prefix}{child.inst_name}"
 
             # When unrolled, current_idx is set - append it to the name
             if child.current_idx is not None:

src/peakrdl_busdecoder/cpuif/taxi_apb/__init__.py

@@ -0,0 +1,3 @@
+from .taxi_apb_cpuif import TaxiAPBCpuif
+
+__all__ = ["TaxiAPBCpuif"]

src/peakrdl_busdecoder/cpuif/taxi_apb/taxi_apb_cpuif.py

@@ -0,0 +1,99 @@
+from typing import TYPE_CHECKING, overload
+
+from systemrdl.node import AddressableNode
+
+from ...utils import get_indexed_path
+from ..base_cpuif import BaseCpuif
+from .taxi_apb_interface import TaxiAPBSVInterface
+
+if TYPE_CHECKING:
+    from ...exporter import BusDecoderExporter
+
+
+class TaxiAPBCpuif(BaseCpuif):
+    template_path = "taxi_apb_tmpl.sv"
+
+    def __init__(self, exp: "BusDecoderExporter") -> None:
+        super().__init__(exp)
+        self._interface = TaxiAPBSVInterface(self)
+        self._interface.master_modport_name = "mst"
+        self._interface.slave_modport_name = "slv"
+
+    @property
+    def is_interface(self) -> bool:
+        return self._interface.is_interface
+
+    @property
+    def port_declaration(self) -> str:
+        """Returns the port declaration for the APB4 interface."""
+        return self._interface.get_port_declaration("s_apb", "m_apb_")
+
+    @overload
+    def signal(self, signal: str, node: None = None, indexer: None = None) -> str: ...
+    @overload
+    def signal(self, signal: str, node: AddressableNode, indexer: str) -> str: ...
+    def signal(self, signal: str, node: AddressableNode | None = None, indexer: str | None = None) -> str:
+        return self._interface.signal(signal, node, indexer)
+
+    def fanout(self, node: AddressableNode) -> str:
+        fanout: dict[str, str] = {}
+        fanout[self.signal("psel", node, "gi")] = (
+            f"cpuif_wr_sel.{get_indexed_path(self.exp.ds.top_node, node, 'gi')}|cpuif_rd_sel.{get_indexed_path(self.exp.ds.top_node, node, 'gi')}"
+        )
+        fanout[self.signal("penable", node, "gi")] = self.signal("penable")
+        fanout[self.signal("pwrite", node, "gi")] = (
+            f"cpuif_wr_sel.{get_indexed_path(self.exp.ds.top_node, node, 'gi')}"
+        )
+        fanout[self.signal("paddr", node, "gi")] = self.signal("paddr")
+        fanout[self.signal("pprot", node, "gi")] = self.signal("pprot")
+        fanout[self.signal("pwdata", node, "gi")] = "cpuif_wr_data"
+        fanout[self.signal("pstrb", node, "gi")] = "cpuif_wr_byte_en"
+        # no user?
+
+        return "\n".join(map(lambda kv: f"assign {kv[0]} = {kv[1]};", fanout.items()))
+
+    def fanin(self, node: AddressableNode | None = None) -> str:
+        fanin: dict[str, str] = {}
+        if node is None:
+            fanin["cpuif_rd_ack"] = "'0"
+            fanin["cpuif_rd_err"] = "'0"
+        else:
+            # Use intermediate signals for interface arrays to avoid
+            # non-constant indexing of interface arrays in procedural blocks
+            if self.is_interface and node.is_array and node.array_dimensions:
+                # Generate array index string [i0][i1]... for the intermediate signal
+                array_idx = "".join(f"[i{i}]" for i in range(len(node.array_dimensions)))
+                fanin["cpuif_rd_ack"] = f"{node.inst_name}_fanin_ready{array_idx}"
+                fanin["cpuif_rd_err"] = f"{node.inst_name}_fanin_err{array_idx}"
+            else:
+                fanin["cpuif_rd_ack"] = self.signal("pready", node, "i")
+                fanin["cpuif_rd_err"] = self.signal("pslverr", node, "i")
+
+        # no user?
+        return "\n".join(map(lambda kv: f"{kv[0]} = {kv[1]};", fanin.items()))
+
+    def readback(self, node: AddressableNode | None = None) -> str:
+        fanin: dict[str, str] = {}
+        if node is None:
+            fanin["cpuif_rd_data"] = "'0"
+        else:
+            # Use intermediate signals for interface arrays to avoid
+            # non-constant indexing of interface arrays in procedural blocks
+            if self.is_interface and node.is_array and node.array_dimensions:
+                # Generate array index string [i0][i1]... for the intermediate signal
+                array_idx = "".join(f"[i{i}]" for i in range(len(node.array_dimensions)))
+                fanin["cpuif_rd_data"] = f"{node.inst_name}_fanin_data{array_idx}"
+            else:
+                fanin["cpuif_rd_data"] = self.signal("prdata", node, "i")
+
+        return "\n".join(map(lambda kv: f"{kv[0]} = {kv[1]};", fanin.items()))
+
+    def fanin_intermediate_assignments(
+        self, node: AddressableNode, inst_name: str, array_idx: str, master_prefix: str, indexed_path: str
+    ) -> list[str]:
+        """Generate intermediate signal assignments for APB4 interface arrays."""
+        return [
+            f"assign {inst_name}_fanin_ready{array_idx} = {master_prefix}{indexed_path}.pready;",
+            f"assign {inst_name}_fanin_err{array_idx} = {master_prefix}{indexed_path}.pslverr;",
+            f"assign {inst_name}_fanin_data{array_idx} = {master_prefix}{indexed_path}.prdata;",
+        ]

src/peakrdl_busdecoder/cpuif/taxi_apb/taxi_apb_interface.py

@@ -0,0 +1,16 @@
+"""Taxi APB-specific interface implementations."""
+
+from ..interface import SVInterface
+
+
+class TaxiAPBSVInterface(SVInterface):
+    """Taxi APB SystemVerilog interface."""
+
+    def get_interface_type(self) -> str:
+        return "taxi_apb_if"
+
+    def get_slave_name(self) -> str:
+        return "s_apb"
+
+    def get_master_prefix(self) -> str:
+        return "m_apb_"

src/peakrdl_busdecoder/cpuif/taxi_apb/taxi_apb_tmpl.sv

@@ -0,0 +1,43 @@
+{%- if cpuif.is_interface %}
+`ifndef SYNTHESIS
+    initial begin
+        assert_bad_addr_width: assert($bits({{cpuif.signal("paddr")}}) >= {{ds.package_name}}::{{ds.module_name|upper}}_MIN_ADDR_WIDTH)
+            else $error("Interface address width of %0d is too small. Shall be at least %0d bits", $bits({{cpuif.signal("paddr")}}), {{ds.package_name}}::{{ds.module_name|upper}}_MIN_ADDR_WIDTH);
+        assert_bad_data_width: assert($bits({{cpuif.signal("pwdata")}}) == {{ds.package_name}}::{{ds.module_name|upper}}_DATA_WIDTH)
+            else $error("Interface data width of %0d is incorrect. Shall be %0d bits", $bits({{cpuif.signal("pwdata")}}), {{ds.package_name}}::{{ds.module_name|upper}}_DATA_WIDTH);
+    end
+    assert_wr_sel: assert property (@(posedge {{cpuif.signal("PCLK")}}) {{cpuif.signal("psel")}} && {{cpuif.signal("pwrite")}} |-> ##1 ({{cpuif.signal("pready")}} || {{cpuif.signal("pslverr")}}))
+        else $error("APB4 Slave port SEL implies that cpuif_wr_sel must be one-hot encoded");
+`endif
+{%- endif %}
+
+assign cpuif_req   = {{cpuif.signal("psel")}};
+assign cpuif_wr_en = {{cpuif.signal("pwrite")}};
+assign cpuif_rd_en = !{{cpuif.signal("pwrite")}};
+
+assign cpuif_wr_addr = {{cpuif.signal("paddr")}};
+assign cpuif_rd_addr = {{cpuif.signal("paddr")}};
+
+assign cpuif_wr_data = {{cpuif.signal("pwdata")}};
+assign cpuif_wr_byte_en = {{cpuif.signal("pstrb")}};
+
+assign {{cpuif.signal("prdata")}} = cpuif_rd_data;
+assign {{cpuif.signal("pready")}} = cpuif_rd_ack;
+assign {{cpuif.signal("pslverr")}} = cpuif_rd_err | cpuif_rd_sel.cpuif_err | cpuif_wr_sel.cpuif_err;
+
+//--------------------------------------------------------------------------
+// Fanout CPU Bus interface signals
+//--------------------------------------------------------------------------
+{{fanout|walk(cpuif=cpuif)}}
+{%- if cpuif.is_interface %}
+
+//--------------------------------------------------------------------------
+// Intermediate signals for interface array fanin
+//--------------------------------------------------------------------------
+{{fanin_intermediate|walk(cpuif=cpuif)}}
+{%- endif %}
+
+//--------------------------------------------------------------------------
+// Fanin CPU Bus interface signals
+//--------------------------------------------------------------------------
+{{fanin|walk(cpuif=cpuif)}}