[topgen] Cleanup PLIC Source/Interrupt Mapping Logic
Signed-off-by: Sam Elliott <selliott@lowrisc.org>
diff --git a/util/topgen/c.py b/util/topgen/c.py
index 3d202c0..9455a68 100644
--- a/util/topgen/c.py
+++ b/util/topgen/c.py
@@ -5,11 +5,13 @@
`top_{name}.h`.
"""
+from collections import OrderedDict
+
from mako.template import Template
class Name(object):
- """We often need to format names in specific ways, this class does so."""
+ """We often need to format names in specific ways; this class does so."""
def __add__(self, other):
return Name(self.parts + other.parts)
@@ -77,6 +79,8 @@
self.constants.append((full_name, value, docstring))
+ return full_name
+
def add_last_constant(self, docstring=""):
assert not self.finalized
@@ -96,11 +100,114 @@
return Template(template).render(enum=self)
+class CArrayMapping(object):
+ def __init__(self, name, output_type_name):
+ self.name = name
+ self.output_type_name = output_type_name
+
+ self.mapping = OrderedDict()
+
+ def add_entry(self, in_name, out_name):
+ self.mapping[in_name] = out_name
+
+ def render_declaration(self):
+ template = (
+ "extern const ${mapping.output_type_name.as_c_type()}\n"
+ " ${mapping.name.as_snake_case()}[${len(mapping.mapping)}];")
+ return Template(template).render(mapping=self)
+
+ def render_definition(self):
+ template = (
+ "const ${mapping.output_type_name.as_c_type()}\n"
+ " ${mapping.name.as_snake_case()}[${len(mapping.mapping)}] = {\n"
+ "% for in_name, out_name in mapping.mapping.items():\n"
+ " [${in_name.as_c_enum()}] = ${out_name.as_c_enum()},\n"
+ "% endfor\n"
+ "};\n")
+ return Template(template).render(mapping=self)
+
+
class TopGenC(object):
def __init__(self, top_info):
self.top = top_info
self._top_name = Name(["top"]) + Name.from_snake_case(top_info["name"])
+ self._init_plic_targets()
+ self._init_plic_mapping()
+
+ def _init_plic_targets(self):
+ enum = CEnum(self._top_name + Name(["plic", "target"]))
+
+ for core_id in range(int(self.top["num_cores"])):
+ enum.add_constant(Name(["ibex", str(core_id)]),
+ docstring="Ibex Core {}".format(core_id))
+
+ enum.add_last_constant("Final PLIC target")
+
+ self.plic_targets = enum
+
+ def _init_plic_mapping(self):
+ """We eventually want to generate a mapping from interrupt id to the
+ source peripheral.
+
+ In order to do so, we generate two enums, and store the generated names
+ in a dictionary that represents the mapping.
+
+ Plic Interrupt ID 0 corresponds to no interrupt, and so no peripheral,
+ so we encode that in the enum as "unknown".
+
+ The interrupts have to be added in order, with "none" first, to ensure
+ that they get the correct mapping to their PLIC id, which is used for
+ addressing the right registers and bits.
+ """
+ sources = CEnum(self._top_name + Name(["plic", "peripheral"]))
+ interrupts = CEnum(self._top_name + Name(["plic", "irq", "id"]))
+ plic_mapping = CArrayMapping(
+ self._top_name + Name(["plic", "interrupt", "for", "peripheral"]),
+ sources.name)
+
+ unknown_source = sources.add_constant(Name(["unknown"]),
+ docstring="Unknown Peripheral")
+ none_irq_id = interrupts.add_constant(Name(["none"]),
+ docstring="No Interrupt")
+ plic_mapping.add_entry(none_irq_id, unknown_source)
+
+ # When we generate the `interrupts` enum, the only info we have about
+ # the source is the module name. We'll use `source_name_map` to map a
+ # short module name to the full name object used for the enum constant.
+ source_name_map = {}
+
+ for name in self.top["interrupt_module"]:
+ source_name = sources.add_constant(Name.from_snake_case(name),
+ docstring=name)
+ source_name_map[name] = source_name
+
+ sources.add_last_constant("Final PLIC peripheral")
+
+ for intr in self.top["interrupt"]:
+ # Some interrupts are multiple bits wide. Here we deal with that by
+ # adding a bit-index suffix
+ if "width" in intr and int(intr["width"]) != 1:
+ for i in range(int(intr["width"])):
+ name = Name.from_snake_case(
+ intr["name"]) + Name([str(i)])
+ irq_id = interrupts.add_constant(name,
+ docstring="{} {}".format(
+ intr["name"], i))
+ source_name = source_name_map[intr["module_name"]]
+ plic_mapping.add_entry(irq_id, source_name)
+ else:
+ name = Name.from_snake_case(intr["name"])
+ irq_id = interrupts.add_constant(name, docstring=intr["name"])
+ source_name = source_name_map[intr["module_name"]]
+ plic_mapping.add_entry(irq_id, source_name)
+
+ interrupts.add_last_constant("The Last Valid Interrupt ID.")
+
+ self.plic_sources = sources
+ self.plic_interrupts = interrupts
+ self.plic_mapping = plic_mapping
+
def modules(self):
return [(m["name"],
MemoryRegion(self._top_name + Name.from_snake_case(m["name"]),
@@ -112,14 +219,3 @@
MemoryRegion(self._top_name + Name.from_snake_case(m["name"]),
m["base_addr"], m["size"]))
for m in self.top["memory"]]
-
- def plic_targets(self):
- enum = CEnum(self._top_name + Name(["plic", "target"]))
-
- for core_id in range(int(self.top["num_cores"])):
- enum.add_constant(Name(["ibex", str(core_id)]),
- docstring="Ibex Core {}".format(core_id))
-
- enum.add_last_constant("Final PLIC target")
-
- return enum
