53bb4300a3
Although useful for debugging, most external tools often complain about such attributes (with notable exception of Vivado). As such, it is better to emit Verilog with these attributes into a separate file such as `design.debug.v` and only emit the attributes that were explicitly placed by the user to `design.v`. This still leaves the (*init*) attribute. See #220 for details.
574 lines
23 KiB
Python
574 lines
23 KiB
Python
from abc import abstractproperty
|
|
|
|
from ..hdl import *
|
|
from ..build import *
|
|
|
|
|
|
__all__ = ["LatticeICE40Platform"]
|
|
|
|
|
|
class LatticeICE40Platform(TemplatedPlatform):
|
|
"""
|
|
IceStorm toolchain
|
|
------------------
|
|
|
|
Required tools:
|
|
* ``yosys``
|
|
* ``nextpnr-ice40``
|
|
* ``icepack``
|
|
|
|
The environment is populated by running the script specified in the environment variable
|
|
``NMIGEN_ENV_IceStorm``, if present.
|
|
|
|
Available overrides:
|
|
* ``verbose``: enables logging of informational messages to standard error.
|
|
* ``read_verilog_opts``: adds options for ``read_verilog`` Yosys command.
|
|
* ``synth_opts``: adds options for ``synth_ice40`` Yosys command.
|
|
* ``script_after_read``: inserts commands after ``read_ilang`` in Yosys script.
|
|
* ``script_after_synth``: inserts commands after ``synth_ice40`` in Yosys script.
|
|
* ``yosys_opts``: adds extra options for ``yosys``.
|
|
* ``nextpnr_opts``: adds extra options for ``nextpnr-ice40``.
|
|
* ``add_pre_pack``: inserts commands at the end in pre-pack Python script.
|
|
* ``add_constraints``: inserts commands at the end in the PCF file.
|
|
|
|
Build products:
|
|
* ``{{name}}.rpt``: Yosys log.
|
|
* ``{{name}}.json``: synthesized RTL.
|
|
* ``{{name}}.tim``: nextpnr log.
|
|
* ``{{name}}.asc``: ASCII bitstream.
|
|
* ``{{name}}.bin``: binary bitstream.
|
|
|
|
iCECube2 toolchain
|
|
------------------
|
|
|
|
This toolchain comes in two variants: ``LSE-iCECube2`` and ``Synplify-iCECube2``.
|
|
|
|
Required tools:
|
|
* iCECube2 toolchain
|
|
* ``tclsh``
|
|
|
|
The environment is populated by setting the necessary environment variables based on
|
|
``NMIGEN_ENV_iCECube2``, which must point to the root of the iCECube2 installation, and
|
|
is required.
|
|
|
|
Available overrides:
|
|
* ``verbose``: enables logging of informational messages to standard error.
|
|
* ``lse_opts``: adds options for LSE.
|
|
* ``script_after_add``: inserts commands after ``add_file`` in Synplify Tcl script.
|
|
* ``script_after_options``: inserts commands after ``set_option`` in Synplify Tcl script.
|
|
* ``add_constraints``: inserts commands in SDC file.
|
|
* ``script_after_flow``: inserts commands after ``run_sbt_backend_auto`` in SBT
|
|
Tcl script.
|
|
|
|
Build products:
|
|
* ``{{name}}_lse.log`` (LSE) or ``{{name}}_design/{{name}}.htm`` (Synplify): synthesis log.
|
|
* ``sbt/outputs/router/{{name}}_timing.rpt``: timing report.
|
|
* ``{{name}}.edf``: EDIF netlist.
|
|
* ``{{name}}.bin``: binary bitstream.
|
|
"""
|
|
|
|
toolchain = None # selected when creating platform
|
|
|
|
device = abstractproperty()
|
|
package = abstractproperty()
|
|
|
|
# IceStorm templates
|
|
|
|
_nextpnr_device_options = {
|
|
"iCE40LP384": "--lp384",
|
|
"iCE40LP1K": "--lp1k",
|
|
"iCE40LP4K": "--lp8k",
|
|
"iCE40LP8K": "--lp8k",
|
|
"iCE40HX1K": "--hx1k",
|
|
"iCE40HX4K": "--hx8k",
|
|
"iCE40HX8K": "--hx8k",
|
|
"iCE40UP5K": "--up5k",
|
|
"iCE40UP3K": "--up5k",
|
|
"iCE5LP4K": "--u4k",
|
|
"iCE5LP2K": "--u4k",
|
|
"iCE5LP1K": "--u4k",
|
|
}
|
|
_nextpnr_package_options = {
|
|
"iCE40LP4K": ":4k",
|
|
"iCE40HX4K": ":4k",
|
|
"iCE40UP3K": "",
|
|
"iCE5LP2K": "",
|
|
"iCE5LP1K": "",
|
|
}
|
|
|
|
_icestorm_required_tools = [
|
|
"yosys",
|
|
"nextpnr-ice40",
|
|
"icepack",
|
|
]
|
|
_icestorm_file_templates = {
|
|
**TemplatedPlatform.build_script_templates,
|
|
"{{name}}.il": r"""
|
|
# {{autogenerated}}
|
|
{{emit_rtlil()}}
|
|
""",
|
|
"{{name}}.ys": r"""
|
|
# {{autogenerated}}
|
|
{% for file in platform.iter_extra_files(".v") -%}
|
|
read_verilog {{get_override("read_opts")|options}} {{file}}
|
|
{% endfor %}
|
|
{% for file in platform.iter_extra_files(".sv") -%}
|
|
read_verilog -sv {{get_override("read_opts")|options}} {{file}}
|
|
{% endfor %}
|
|
read_ilang {{name}}.il
|
|
{{get_override("script_after_read")|default("# (script_after_read placeholder)")}}
|
|
synth_ice40 {{get_override("synth_opts")|options}} -top {{name}}
|
|
{{get_override("script_after_synth")|default("# (script_after_synth placeholder)")}}
|
|
write_json {{name}}.json
|
|
""",
|
|
"{{name}}_pre_pack.py": r"""
|
|
# {{autogenerated}}
|
|
{% for signal, frequency in platform.iter_clock_constraints() -%}
|
|
{# Clock in MHz #}
|
|
ctx.addClock("{{signal|hierarchy(".")}}", {{frequency/1000000}})
|
|
{% endfor%}
|
|
{{get_override("add_pre_pack")|default("# (add_pre_pack placeholder)")}}
|
|
""",
|
|
"{{name}}.pcf": r"""
|
|
# {{autogenerated}}
|
|
{% for port_name, pin_name, attrs in platform.iter_port_constraints_bits() -%}
|
|
set_io {{port_name}} {{pin_name}}
|
|
{% endfor %}
|
|
{{get_override("add_constraints")|default("# (add_constraints placeholder)")}}
|
|
""",
|
|
}
|
|
_icestorm_command_templates = [
|
|
r"""
|
|
{{get_tool("yosys")}}
|
|
{{quiet("-q")}}
|
|
{{get_override("yosys_opts")|options}}
|
|
-l {{name}}.rpt
|
|
{{name}}.ys
|
|
""",
|
|
r"""
|
|
{{get_tool("nextpnr-ice40")}}
|
|
{{quiet("--quiet")}}
|
|
{{get_override("nextpnr_opts")|options}}
|
|
--log {{name}}.tim
|
|
{{platform._nextpnr_device_options[platform.device]}}
|
|
--package
|
|
{{platform.package|lower}}{{platform._nextpnr_package_options[platform.device]}}
|
|
--json {{name}}.json
|
|
--pcf {{name}}.pcf
|
|
--pre-pack {{name}}_pre_pack.py
|
|
--asc {{name}}.asc
|
|
""",
|
|
r"""
|
|
{{get_tool("icepack")}}
|
|
{{verbose("-v")}}
|
|
{{name}}.asc
|
|
{{name}}.bin
|
|
"""
|
|
]
|
|
|
|
# iCECube2 templates
|
|
|
|
_icecube2_required_tools = [
|
|
"synthesis",
|
|
"synpwrap",
|
|
"tclsh",
|
|
]
|
|
_icecube2_file_templates = {
|
|
**TemplatedPlatform.build_script_templates,
|
|
"build_{{name}}.sh": r"""
|
|
# {{autogenerated}}
|
|
set -e{{verbose("x")}}
|
|
if [ -n "${{platform._toolchain_env_var}}" ]; then
|
|
# LSE environment
|
|
export LD_LIBRARY_PATH=${{platform._toolchain_env_var}}/LSE/bin/lin64:$LD_LIBRARY_PATH
|
|
export PATH=${{platform._toolchain_env_var}}/LSE/bin/lin64:$PATH
|
|
export FOUNDRY=${{platform._toolchain_env_var}}/LSE
|
|
# Synplify environment
|
|
export LD_LIBRARY_PATH=${{platform._toolchain_env_var}}/sbt_backend/bin/linux/opt/synpwrap:$LD_LIBRARY_PATH
|
|
export PATH=${{platform._toolchain_env_var}}/sbt_backend/bin/linux/opt/synpwrap:$PATH
|
|
export SYNPLIFY_PATH=${{platform._toolchain_env_var}}/synpbase
|
|
# Common environment
|
|
export SBT_DIR=${{platform._toolchain_env_var}}/sbt_backend
|
|
else
|
|
echo "Variable ${{platform._toolchain_env_var}} must be set" >&2; exit 1
|
|
fi
|
|
{{emit_commands("sh")}}
|
|
""",
|
|
"{{name}}.v": r"""
|
|
/* {{autogenerated}} */
|
|
{{emit_verilog()}}
|
|
""",
|
|
"{{name}}.debug.v": r"""
|
|
/* {{autogenerated}} */
|
|
{{emit_debug_verilog()}}
|
|
""",
|
|
"{{name}}_lse.prj": r"""
|
|
# {{autogenerated}}
|
|
-a SBT{{platform.family}}
|
|
-d {{platform.device}}
|
|
-t {{platform.package}}
|
|
{{get_override("lse_opts")|options|default("# (lse_opts placeholder)")}}
|
|
{% for file in platform.iter_extra_files(".v") -%}
|
|
-ver {{file}}
|
|
{% endfor %}
|
|
-ver {{name}}.v
|
|
-sdc {{name}}.sdc
|
|
-top {{name}}
|
|
-output_edif {{name}}.edf
|
|
-logfile {{name}}_lse.log
|
|
""",
|
|
"{{name}}_syn.prj": r"""
|
|
# {{autogenerated}}
|
|
{% for file in platform.iter_extra_files(".v", ".sv", ".vhd", ".vhdl") -%}
|
|
add_file -verilog {{file}}
|
|
{% endfor %}
|
|
add_file -verilog {{name}}.v
|
|
add_file -constraint {{name}}.sdc
|
|
{{get_override("script_after_add")|default("# (script_after_add placeholder)")}}
|
|
impl -add {{name}}_design -type fpga
|
|
set_option -technology SBT{{platform.family}}
|
|
set_option -part {{platform.device}}
|
|
set_option -package {{platform.package}}
|
|
{{get_override("script_after_options")|default("# (script_after_options placeholder)")}}
|
|
project -result_format edif
|
|
project -result_file {{name}}.edf
|
|
impl -active {{name}}_design
|
|
project -run compile
|
|
project -run map
|
|
project -run fpga_mapper
|
|
file copy -force -- {{name}}_design/{{name}}.edf {{name}}.edf
|
|
""",
|
|
"{{name}}.sdc": r"""
|
|
# {{autogenerated}}
|
|
{% for signal, frequency in platform.iter_clock_constraints() -%}
|
|
create_clock -name {{signal.name}} -period {{1000000000/frequency}} [get_nets {{signal|hierarchy("/")}}]
|
|
{% endfor %}
|
|
{{get_override("add_constraints")|default("# (add_constraints placeholder)")}}
|
|
""",
|
|
"{{name}}.tcl": r"""
|
|
# {{autogenerated}}
|
|
set device {{platform.device}}-{{platform.package}}
|
|
set top_module {{name}}
|
|
set proj_dir .
|
|
set output_dir .
|
|
set edif_file {{name}}
|
|
set tool_options ":edifparser -y {{name}}.pcf"
|
|
set sbt_root $::env(SBT_DIR)
|
|
append sbt_tcl $sbt_root "/tcl/sbt_backend_synpl.tcl"
|
|
source $sbt_tcl
|
|
run_sbt_backend_auto $device $top_module $proj_dir $output_dir $tool_options $edif_file
|
|
{{get_override("script_after_file")|default("# (script_after_file placeholder)")}}
|
|
file copy -force -- sbt/outputs/bitmap/{{name}}_bitmap.bin {{name}}.bin
|
|
exit
|
|
""",
|
|
"{{name}}.pcf": r"""
|
|
# {{autogenerated}}
|
|
{% for port_name, pin_name, attrs in platform.iter_port_constraints_bits() -%}
|
|
set_io {{port_name}} {{pin_name}}
|
|
{% endfor %}
|
|
""",
|
|
}
|
|
_lse_icecube2_command_templates = [
|
|
r"""synthesis -f {{name}}_lse.prj""",
|
|
r"""tclsh {{name}}.tcl""",
|
|
]
|
|
_synplify_icecube2_command_templates = [
|
|
r"""synpwrap -prj {{name}}_syn.prj -log {{name}}_syn.log""",
|
|
r"""tclsh {{name}}.tcl""",
|
|
]
|
|
|
|
# Common logic
|
|
|
|
def __init__(self, *, toolchain="IceStorm"):
|
|
super().__init__()
|
|
|
|
assert toolchain in ("IceStorm", "LSE-iCECube2", "Synplify-iCECube2")
|
|
self.toolchain = toolchain
|
|
|
|
@property
|
|
def family(self):
|
|
if self.device.startswith("iCE40"):
|
|
return "iCE40"
|
|
if self.device.startswith("iCE5"):
|
|
return "iCE5"
|
|
assert False
|
|
|
|
@property
|
|
def _toolchain_env_var(self):
|
|
if self.toolchain == "IceStorm":
|
|
return f"NMIGEN_ENV_{self.toolchain}"
|
|
if self.toolchain in ("LSE-iCECube2", "Synplify-iCECube2"):
|
|
return f"NMIGEN_ENV_iCECube2"
|
|
assert False
|
|
|
|
@property
|
|
def required_tools(self):
|
|
if self.toolchain == "IceStorm":
|
|
return self._icestorm_required_tools
|
|
if self.toolchain in ("LSE-iCECube2", "Synplify-iCECube2"):
|
|
return self._icecube2_required_tools
|
|
assert False
|
|
|
|
@property
|
|
def file_templates(self):
|
|
if self.toolchain == "IceStorm":
|
|
return self._icestorm_file_templates
|
|
if self.toolchain in ("LSE-iCECube2", "Synplify-iCECube2"):
|
|
return self._icecube2_file_templates
|
|
assert False
|
|
|
|
@property
|
|
def command_templates(self):
|
|
if self.toolchain == "IceStorm":
|
|
return self._icestorm_command_templates
|
|
if self.toolchain == "LSE-iCECube2":
|
|
return self._lse_icecube2_command_templates
|
|
if self.toolchain == "Synplify-iCECube2":
|
|
return self._synplify_icecube2_command_templates
|
|
assert False
|
|
|
|
def create_missing_domain(self, name):
|
|
# For unknown reasons (no errata was ever published, and no documentation mentions this
|
|
# issue), iCE40 BRAMs read as zeroes for ~3 us after configuration and release of internal
|
|
# global reset. Note that this is a *time-based* delay, generated purely by the internal
|
|
# oscillator, which may not be observed nor influenced directly. For details, see links:
|
|
# * https://github.com/cliffordwolf/icestorm/issues/76#issuecomment-289270411
|
|
# * https://github.com/cliffordwolf/icotools/issues/2#issuecomment-299734673
|
|
#
|
|
# To handle this, it is necessary to have a global reset in any iCE40 design that may
|
|
# potentially instantiate BRAMs, and assert this reset for >3 us after configuration.
|
|
# (We add a margin of 5x to allow for PVT variation.) If the board includes a dedicated
|
|
# reset line, this line is ORed with the power on reset.
|
|
#
|
|
# The power-on reset timer counts up because the vendor tools do not support initialization
|
|
# of flip-flops.
|
|
if name == "sync" and self.default_clk is not None:
|
|
clk_i = self.request(self.default_clk).i
|
|
if self.default_rst is not None:
|
|
rst_i = self.request(self.default_rst).i
|
|
|
|
m = Module()
|
|
# Power-on-reset domain
|
|
m.domains += ClockDomain("por", reset_less=True, local=True)
|
|
delay = int(15e-6 * self.default_clk_frequency)
|
|
timer = Signal(max=delay)
|
|
ready = Signal()
|
|
m.d.comb += ClockSignal("por").eq(clk_i)
|
|
with m.If(timer == delay):
|
|
m.d.por += ready.eq(1)
|
|
with m.Else():
|
|
m.d.por += timer.eq(timer + 1)
|
|
# Primary domain
|
|
m.domains += ClockDomain("sync")
|
|
m.d.comb += ClockSignal("sync").eq(clk_i)
|
|
if self.default_rst is not None:
|
|
m.d.comb += ResetSignal("sync").eq(~ready | rst_i)
|
|
else:
|
|
m.d.comb += ResetSignal("sync").eq(~ready)
|
|
return m
|
|
|
|
def should_skip_port_component(self, port, attrs, component):
|
|
# On iCE40, a differential input is placed by only instantiating an SB_IO primitive for
|
|
# the pin with z=0, which is the non-inverting pin. The pinout unfortunately differs
|
|
# between LP/HX and UP series:
|
|
# * for LP/HX, z=0 is DPxxB (B is non-inverting, A is inverting)
|
|
# * for UP, z=0 is IOB_xxA (A is non-inverting, B is inverting)
|
|
if attrs.get("IO_STANDARD", "SB_LVCMOS") == "SB_LVDS_INPUT" and component == "n":
|
|
return True
|
|
return False
|
|
|
|
def _get_io_buffer(self, m, pin, port, attrs, *, i_invert=False, o_invert=False,
|
|
invert_lut=False):
|
|
def get_dff(clk, d, q):
|
|
m.submodules += Instance("$dff",
|
|
p_CLK_POLARITY=1,
|
|
p_WIDTH=len(d),
|
|
i_CLK=clk,
|
|
i_D=d,
|
|
o_Q=q)
|
|
|
|
def get_ineg(y, invert):
|
|
if invert_lut:
|
|
a = Signal.like(y, name_suffix="_x{}".format(1 if invert else 0))
|
|
for bit in range(len(y)):
|
|
m.submodules += Instance("SB_LUT4",
|
|
p_LUT_INIT=Const(0b01 if invert else 0b10, 16),
|
|
i_I0=a[bit],
|
|
i_I1=Const(0),
|
|
i_I2=Const(0),
|
|
i_I3=Const(0),
|
|
o_O=y[bit])
|
|
return a
|
|
elif invert:
|
|
a = Signal.like(y, name_suffix="_n")
|
|
m.d.comb += y.eq(~a)
|
|
return a
|
|
else:
|
|
return y
|
|
|
|
def get_oneg(a, invert):
|
|
if invert_lut:
|
|
y = Signal.like(a, name_suffix="_x{}".format(1 if invert else 0))
|
|
for bit in range(len(a)):
|
|
m.submodules += Instance("SB_LUT4",
|
|
p_LUT_INIT=Const(0b01 if invert else 0b10, 16),
|
|
i_I0=a[bit],
|
|
i_I1=Const(0),
|
|
i_I2=Const(0),
|
|
i_I3=Const(0),
|
|
o_O=y[bit])
|
|
return y
|
|
elif invert:
|
|
y = Signal.like(a, name_suffix="_n")
|
|
m.d.comb += y.eq(~a)
|
|
return y
|
|
else:
|
|
return a
|
|
|
|
if "GLOBAL" in attrs:
|
|
is_global_input = bool(attrs["GLOBAL"])
|
|
del attrs["GLOBAL"]
|
|
else:
|
|
is_global_input = False
|
|
assert not (is_global_input and i_invert)
|
|
|
|
if "i" in pin.dir:
|
|
if pin.xdr < 2:
|
|
pin_i = get_ineg(pin.i, i_invert)
|
|
elif pin.xdr == 2:
|
|
pin_i0 = get_ineg(pin.i0, i_invert)
|
|
pin_i1 = get_ineg(pin.i1, i_invert)
|
|
if "o" in pin.dir:
|
|
if pin.xdr < 2:
|
|
pin_o = get_oneg(pin.o, o_invert)
|
|
elif pin.xdr == 2:
|
|
pin_o0 = get_oneg(pin.o0, o_invert)
|
|
pin_o1 = get_oneg(pin.o1, o_invert)
|
|
|
|
if "i" in pin.dir and pin.xdr == 2:
|
|
i0_ff = Signal.like(pin_i0, name_suffix="_ff")
|
|
i1_ff = Signal.like(pin_i1, name_suffix="_ff")
|
|
get_dff(pin.i_clk, i0_ff, pin_i0)
|
|
get_dff(pin.i_clk, i1_ff, pin_i1)
|
|
if "o" in pin.dir and pin.xdr == 2:
|
|
o1_ff = Signal.like(pin_o1, name_suffix="_ff")
|
|
get_dff(pin.o_clk, pin_o1, o1_ff)
|
|
|
|
for bit in range(len(port)):
|
|
io_args = [
|
|
("io", "PACKAGE_PIN", port[bit]),
|
|
*(("p", key, value) for key, value in attrs.items()),
|
|
]
|
|
|
|
if "i" not in pin.dir:
|
|
# If no input pin is requested, it is important to use a non-registered input pin
|
|
# type, because an output-only pin would not have an input clock, and if its input
|
|
# is configured as registered, this would prevent a co-located input-capable pin
|
|
# from using an input clock.
|
|
i_type = 0b01 # PIN_INPUT
|
|
elif pin.xdr == 0:
|
|
i_type = 0b01 # PIN_INPUT
|
|
elif pin.xdr > 0:
|
|
i_type = 0b00 # PIN_INPUT_REGISTERED aka PIN_INPUT_DDR
|
|
if "o" not in pin.dir:
|
|
o_type = 0b0000 # PIN_NO_OUTPUT
|
|
elif pin.xdr == 0 and pin.dir == "o":
|
|
o_type = 0b0110 # PIN_OUTPUT
|
|
elif pin.xdr == 0:
|
|
o_type = 0b1010 # PIN_OUTPUT_TRISTATE
|
|
elif pin.xdr == 1 and pin.dir == "o":
|
|
o_type = 0b0101 # PIN_OUTPUT_REGISTERED
|
|
elif pin.xdr == 1:
|
|
o_type = 0b1101 # PIN_OUTPUT_REGISTERED_ENABLE_REGISTERED
|
|
elif pin.xdr == 2 and pin.dir == "o":
|
|
o_type = 0b0100 # PIN_OUTPUT_DDR
|
|
elif pin.xdr == 2:
|
|
o_type = 0b1100 # PIN_OUTPUT_DDR_ENABLE_REGISTERED
|
|
io_args.append(("p", "PIN_TYPE", C((o_type << 2) | i_type, 6)))
|
|
|
|
if hasattr(pin, "i_clk"):
|
|
io_args.append(("i", "INPUT_CLK", pin.i_clk))
|
|
if hasattr(pin, "o_clk"):
|
|
io_args.append(("i", "OUTPUT_CLK", pin.o_clk))
|
|
|
|
if "i" in pin.dir:
|
|
if pin.xdr == 0 and is_global_input:
|
|
io_args.append(("o", "GLOBAL_BUFFER_OUTPUT", pin.i[bit]))
|
|
elif pin.xdr < 2:
|
|
io_args.append(("o", "D_IN_0", pin_i[bit]))
|
|
elif pin.xdr == 2:
|
|
# Re-register both inputs before they enter fabric. This increases hold time
|
|
# to an entire cycle, and adds one cycle of latency.
|
|
io_args.append(("o", "D_IN_0", i0_ff[bit]))
|
|
io_args.append(("o", "D_IN_1", i1_ff[bit]))
|
|
if "o" in pin.dir:
|
|
if pin.xdr < 2:
|
|
io_args.append(("i", "D_OUT_0", pin_o[bit]))
|
|
elif pin.xdr == 2:
|
|
# Re-register negedge output after it leaves fabric. This increases setup time
|
|
# to an entire cycle, and doesn't add latency.
|
|
io_args.append(("i", "D_OUT_0", pin_o0[bit]))
|
|
io_args.append(("i", "D_OUT_1", o1_ff[bit]))
|
|
|
|
if pin.dir in ("oe", "io"):
|
|
io_args.append(("i", "OUTPUT_ENABLE", pin.oe))
|
|
|
|
if is_global_input:
|
|
m.submodules["{}_{}".format(pin.name, bit)] = Instance("SB_GB_IO", *io_args)
|
|
else:
|
|
m.submodules["{}_{}".format(pin.name, bit)] = Instance("SB_IO", *io_args)
|
|
|
|
def get_input(self, pin, port, attrs, invert):
|
|
self._check_feature("single-ended input", pin, attrs,
|
|
valid_xdrs=(0, 1, 2), valid_attrs=True)
|
|
m = Module()
|
|
self._get_io_buffer(m, pin, port, attrs, i_invert=invert)
|
|
return m
|
|
|
|
def get_output(self, pin, port, attrs, invert):
|
|
self._check_feature("single-ended output", pin, attrs,
|
|
valid_xdrs=(0, 1, 2), valid_attrs=True)
|
|
m = Module()
|
|
self._get_io_buffer(m, pin, port, attrs, o_invert=invert)
|
|
return m
|
|
|
|
def get_tristate(self, pin, port, attrs, invert):
|
|
self._check_feature("single-ended tristate", pin, attrs,
|
|
valid_xdrs=(0, 1, 2), valid_attrs=True)
|
|
m = Module()
|
|
self._get_io_buffer(m, pin, port, attrs, o_invert=invert)
|
|
return m
|
|
|
|
def get_input_output(self, pin, port, attrs, invert):
|
|
self._check_feature("single-ended input/output", pin, attrs,
|
|
valid_xdrs=(0, 1, 2), valid_attrs=True)
|
|
m = Module()
|
|
self._get_io_buffer(m, pin, port, attrs, i_invert=invert, o_invert=invert)
|
|
return m
|
|
|
|
def get_diff_input(self, pin, p_port, n_port, attrs, invert):
|
|
self._check_feature("differential input", pin, attrs,
|
|
valid_xdrs=(0, 1, 2), valid_attrs=True)
|
|
m = Module()
|
|
# See comment in should_skip_port_component above.
|
|
self._get_io_buffer(m, pin, p_port, attrs, i_invert=invert)
|
|
return m
|
|
|
|
def get_diff_output(self, pin, p_port, n_port, attrs, invert):
|
|
self._check_feature("differential output", pin, attrs,
|
|
valid_xdrs=(0, 1, 2), valid_attrs=True)
|
|
m = Module()
|
|
# Note that the non-inverting output pin is not driven the same way as a regular
|
|
# output pin. The inverter introduces a delay, so for a non-inverting output pin,
|
|
# an identical delay is introduced by instantiating a LUT. This makes the waveform
|
|
# perfectly symmetric in the xdr=0 case.
|
|
self._get_io_buffer(m, pin, p_port, attrs, o_invert= invert, invert_lut=True)
|
|
self._get_io_buffer(m, pin, n_port, attrs, o_invert=not invert, invert_lut=True)
|
|
return m
|
|
|
|
# Tristate and bidirectional buffers are not supported on iCE40 because it requires external
|
|
# termination, which is incompatible for input and output differential I/Os.
|
|
|
|
# CDC primitives are not currently specialized for iCE40. It is not known if iCECube2 supports
|
|
# the necessary attributes; nextpnr-ice40 does not.
|