litex/mibuild/generic_platform.py

244 lines
7.1 KiB
Python

from copy import copy
import os, argparse
from migen.fhdl.std import *
from migen.genlib.record import Record
from migen.fhdl import verilog
from mibuild import tools
class ConstraintError(Exception):
pass
class Pins:
def __init__(self, *identifiers):
self.identifiers = []
for i in identifiers:
self.identifiers += i.split()
class IOStandard:
def __init__(self, name):
self.name = name
class Drive:
def __init__(self, strength):
self.strength = strength
class Misc:
def __init__(self, misc):
self.misc = misc
class Subsignal:
def __init__(self, name, *constraints):
self.name = name
self.constraints = list(constraints)
class PlatformInfo:
def __init__(self, info):
self.info = info
def _lookup(description, name, number):
for resource in description:
if resource[0] == name and (number is None or resource[1] == number):
return resource
raise ConstraintError("Resource not found: " + name + ":" + str(number))
def _resource_type(resource):
t = None
for element in resource[2:]:
if isinstance(element, Pins):
assert(t is None)
t = len(element.identifiers)
elif isinstance(element, Subsignal):
if t is None:
t = []
assert(isinstance(t, list))
n_bits = None
for c in element.constraints:
if isinstance(c, Pins):
assert(n_bits is None)
n_bits = len(c.identifiers)
t.append((element.name, n_bits))
return t
def _separate_pins(constraints):
pins = None
others = []
for c in constraints:
if isinstance(c, Pins):
assert(pins is None)
pins = c.identifiers
else:
others.append(c)
return pins, others
class ConstraintManager:
def __init__(self, description):
self.available = list(description)
self.matched = []
self.platform_commands = []
def request(self, name, number=None):
resource = _lookup(self.available, name, number)
rt = _resource_type(resource)
if isinstance(rt, int):
obj = Signal(rt, name_override=resource[0])
else:
obj = Record(rt, name=resource[0])
for element in resource[2:]:
if isinstance(element, PlatformInfo):
obj.platform_info = element.info
break
self.available.remove(resource)
self.matched.append((resource, obj))
return obj
def lookup_request(self, name, number=None):
for resource, obj in self.matched:
if resource[0] == name and (number is None or resource[1] == number):
return obj
raise ConstraintError("Resource not found: " + name + ":" + str(number))
def add_platform_command(self, command, **signals):
self.platform_commands.append((command, signals))
def get_io_signals(self):
r = set()
for resource, obj in self.matched:
if isinstance(obj, Signal):
r.add(obj)
else:
r.update(obj.flatten())
return r
def get_sig_constraints(self):
r = []
for resource, obj in self.matched:
name = resource[0]
number = resource[1]
has_subsignals = False
top_constraints = []
for element in resource[2:]:
if isinstance(element, Subsignal):
has_subsignals = True
else:
top_constraints.append(element)
if has_subsignals:
for element in resource[2:]:
if isinstance(element, Subsignal):
sig = getattr(obj, element.name)
pins, others = _separate_pins(top_constraints + element.constraints)
r.append((sig, pins, others, (name, number, element.name)))
else:
pins, others = _separate_pins(top_constraints)
r.append((obj, pins, others, (name, number, None)))
return r
def get_platform_commands(self):
return self.platform_commands
def save(self):
return copy(self.available), copy(self.matched), copy(self.platform_commands)
def restore(self, backup):
self.available, self.matched, self.platform_commands = backup
class GenericPlatform:
def __init__(self, device, io, default_crg_factory=None, name=None):
self.device = device
self.constraint_manager = ConstraintManager(io)
self.default_crg_factory = default_crg_factory
if name is None:
name = self.__module__.split(".")[-1]
self.name = name
self.sources = []
self.finalized = False
def request(self, *args, **kwargs):
return self.constraint_manager.request(*args, **kwargs)
def lookup_request(self, *args, **kwargs):
return self.constraint_manager.lookup_request(*args, **kwargs)
def add_platform_command(self, *args, **kwargs):
return self.constraint_manager.add_platform_command(*args, **kwargs)
def finalize(self, fragment, *args, **kwargs):
if self.finalized:
raise ConstraintError("Already finalized")
self.do_finalize(fragment, *args, **kwargs)
self.finalized = True
def do_finalize(self, fragment, *args, **kwargs):
"""overload this and e.g. add_platform_command()'s after the
modules had their say"""
pass
def add_source(self, filename, language=None):
if language is None:
language = tools.language_by_filename(filename)
if language is None:
language = "verilog" # default to Verilog
filename = os.path.abspath(filename)
self.sources.append((filename, language))
def add_sources(self, path, *filenames, language=None):
for f in filenames:
self.add_source(os.path.join(path, f), language)
def add_source_dir(self, path):
for root, dirs, files in os.walk(path):
for filename in files:
language = tools.language_by_filename(filename)
if language is not None:
self.add_source(os.path.join(root, filename), language)
def get_verilog(self, fragment, **kwargs):
if not isinstance(fragment, Fragment):
fragment = fragment.get_fragment()
# We may create a temporary clock/reset generator that would request pins.
# Save the constraint manager state so that such pin requests disappear
# at the end of this function.
backup = self.constraint_manager.save()
try:
# if none exists, create a default clock domain and drive it
if not fragment.clock_domains:
if self.default_crg_factory is None:
raise NotImplementedError("No clock/reset generator defined by either platform or user")
crg = self.default_crg_factory(self)
frag = fragment + crg.get_fragment()
else:
frag = fragment
# finalize
self.finalize(fragment)
# generate Verilog
src, vns = verilog.convert(frag, self.constraint_manager.get_io_signals(),
return_ns=True, create_clock_domains=False, **kwargs)
# resolve signal names in constraints
sc = self.constraint_manager.get_sig_constraints()
named_sc = [(vns.get_name(sig), pins, others, resource) for sig, pins, others, resource in sc]
# resolve signal names in platform commands
pc = self.constraint_manager.get_platform_commands()
named_pc = []
for template, args in pc:
name_dict = dict((k, vns.get_name(sig)) for k, sig in args.items())
named_pc.append(template.format(**name_dict))
finally:
self.constraint_manager.restore(backup)
return src, named_sc, named_pc
def build(self, fragment):
raise NotImplementedError("GenericPlatform.build must be overloaded")
def add_arguments(self, parser):
pass # default: no arguments
def build_arg_ns(self, ns, *args, **kwargs):
self.build(*args, **kwargs)
def build_cmdline(self, *args, **kwargs):
parser = argparse.ArgumentParser(description="FPGA bitstream build system")
self.add_arguments(parser)
ns = parser.parse_args()
self.build_arg_ns(ns, *args, **kwargs)