nmigen.git
2 years ago*: remove unused imports
Robin Ole Heinemann [Tue, 18 May 2021 18:39:57 +0000 (20:39 +0200)]
*: remove unused imports

2 years agotests.hdl.dsl: add tests for mis-nested Switch/Case and FSM/State statements
Thomas Watson [Tue, 11 May 2021 02:02:29 +0000 (21:02 -0500)]
tests.hdl.dsl: add tests for mis-nested Switch/Case and FSM/State statements

2 years agohdl.dsl: raise SyntaxError for mis-nested If/Elif/Else statements
Thomas Watson [Tue, 11 May 2021 01:59:34 +0000 (20:59 -0500)]
hdl.dsl: raise SyntaxError for mis-nested If/Elif/Else statements

2 years agovendor.lattice_{ecp5,machxo_2_3l}: remove -forceAll from Diamond scripts.
Adam Greig [Mon, 12 Apr 2021 09:48:20 +0000 (10:48 +0100)]
vendor.lattice_{ecp5,machxo_2_3l}: remove -forceAll from Diamond scripts.

Fixes #604.

2 years agoCI: fix sri-csl/formal-methods PPA series.
whitequark [Thu, 18 Mar 2021 23:56:52 +0000 (23:56 +0000)]
CI: fix sri-csl/formal-methods PPA series.

GHA's Ubuntu has been upgraded to Focal.

2 years agohdl.ast: handle int subclasses as slice start/stop values.
whitequark [Thu, 18 Mar 2021 23:52:23 +0000 (23:52 +0000)]
hdl.ast: handle int subclasses as slice start/stop values.

Fixes #601.

2 years agocompat.genlib.roundrobin: fix missing imports
dx-mon [Thu, 4 Feb 2021 03:10:44 +0000 (03:10 +0000)]
compat.genlib.roundrobin: fix missing imports

2 years agovendor.xilinx_7series: fix tool names for symbiflow.
nickoe [Sun, 31 Jan 2021 18:08:44 +0000 (19:08 +0100)]
vendor.xilinx_7series: fix tool names for symbiflow.

Prefix "tools" with symbiflow_ as is done for the QuickLogic Symbiflow
toolchain. Installing symbiflow gives me the tools with the preifx, so I
guess this is the correct way to move forward.

2 years agovendor.lattice_ecp5: correctly generate OE signaling when xdr=0
Katherine Temkin [Mon, 25 Jan 2021 15:41:45 +0000 (08:41 -0700)]
vendor.lattice_ecp5: correctly generate OE signaling when xdr=0

This fixes a logic bug introduced in
6ce2b21e196a0f93b82748ed046098331d20b3bf.

2 years agovendor.lattice_ecp5: replicate OE signal for each output bit.
Adam Greig [Sat, 23 Jan 2021 18:06:52 +0000 (18:06 +0000)]
vendor.lattice_ecp5: replicate OE signal for each output bit.

nextpnr can only pack OE FFs into IOLOGIC when there's one OFS1P3DX per
output, rather than one shared instance.

2 years agodocs: Update up_counter to avoid deprecation warning
Joel Stanley [Fri, 15 Jan 2021 02:58:21 +0000 (13:28 +1030)]
docs: Update up_counter to avoid deprecation warning

nmigen/docs/_code/up_counter.py:44: DeprecationWarning: instead of nmigen.back.pysim.*, use nmigen.sim.*
  from nmigen.back.pysim import Simulator

2 years agovendor.lattice_ecp5: remove outdated comment in ECP5 platform.
Adam Greig [Thu, 14 Jan 2021 11:34:03 +0000 (11:34 +0000)]
vendor.lattice_ecp5: remove outdated comment in ECP5 platform.

Starting with nextpnr c6401413a, nextpnr does pack *FS1P3DX
into IOLOGIC cells.

2 years agolib.fifo.AsyncFIFOBuffered: fix output register accounting
Robin Ole Heinemann [Sat, 2 Jan 2021 23:17:48 +0000 (00:17 +0100)]
lib.fifo.AsyncFIFOBuffered: fix output register accounting

2 years agolib.fifo.AsyncFIFOBuffered: fix FFSynchronizer latency
Robin Ole Heinemann [Sat, 2 Jan 2021 23:14:26 +0000 (00:14 +0100)]
lib.fifo.AsyncFIFOBuffered: fix FFSynchronizer latency

2 years agolib.fifo: use proper clock domains in AsyncFIFO tests
Robin Ole Heinemann [Sat, 2 Jan 2021 23:13:46 +0000 (00:13 +0100)]
lib.fifo: use proper clock domains in AsyncFIFO tests

2 years agolib.fifo.AsyncFIFOBuffered: use FFSynchronizer instead of AsyncFFsynchronizer
Robin Ole Heinemann [Sat, 2 Jan 2021 23:12:31 +0000 (00:12 +0100)]
lib.fifo.AsyncFIFOBuffered: use FFSynchronizer instead of AsyncFFsynchronizer

AsyncFFsynchronizer only synchronizes one edge

2 years agoRevert "vendor.xilinx_7series: byte swap generated bitstream"
whitequark [Sat, 12 Dec 2020 22:08:57 +0000 (22:08 +0000)]
Revert "vendor.xilinx_7series: byte swap generated bitstream"

This reverts commit 14a5c42a8bd425a4882ba566b26e11bd6d1e1721.

2 years agohdl.ast: formatting. NFC.
whitequark [Sat, 12 Dec 2020 14:11:40 +0000 (14:11 +0000)]
hdl.ast: formatting. NFC.

2 years agohdl.ast: normalize case values to two's complement, not signed binary.
whitequark [Sat, 12 Dec 2020 12:42:12 +0000 (12:42 +0000)]
hdl.ast: normalize case values to two's complement, not signed binary.

This was an especially insidious bug because the minus character is
valid in case values but has a completely different meaning (wildcard
rather than sign).

Fixes #559.

2 years agoback.rtlil: give private items an appropriate name. NFCI.
whitequark [Sat, 12 Dec 2020 12:18:59 +0000 (12:18 +0000)]
back.rtlil: give private items an appropriate name. NFCI.

2 years agobuild.plat: make `verbose` work like all other overrides.
whitequark [Tue, 24 Nov 2020 23:07:09 +0000 (23:07 +0000)]
build.plat: make `verbose` work like all other overrides.

Fixes #497.

2 years agovendor.intel: implement `add_settings` (QSF) and `add_constraints` (SDC) overrides.
whitequark [Tue, 24 Nov 2020 20:35:58 +0000 (20:35 +0000)]
vendor.intel: implement `add_settings` (QSF) and `add_constraints` (SDC) overrides.

2 years agovendor.xilinx_spartan_3_6: fix typo.
whitequark [Sun, 22 Nov 2020 00:16:02 +0000 (00:16 +0000)]
vendor.xilinx_spartan_3_6: fix typo.

This was introduced in commit 2f8669ca.

Fixes #549.

2 years agohdl.ast: remove dead code. NFC.
whitequark [Sat, 21 Nov 2020 17:29:55 +0000 (17:29 +0000)]
hdl.ast: remove dead code. NFC.

See #548.

2 years agonmigen.hdl.rec: restore Record.shape().
awygle [Tue, 17 Nov 2020 19:36:58 +0000 (11:36 -0800)]
nmigen.hdl.rec: restore Record.shape().

This method was lost in commit abbebf8e.

2 years agosim._pyrtl: mask Mux selection operand.
Marcelina Kościelnicka [Sat, 14 Nov 2020 15:22:34 +0000 (16:22 +0100)]
sim._pyrtl: mask Mux selection operand.

Otherwise it behaves funny when it's eg. the result of operator ~.

2 years agovendor.quicklogic: enable SoC clock configuration
Jan Kowalewski [Fri, 13 Nov 2020 12:58:11 +0000 (13:58 +0100)]
vendor.quicklogic: enable SoC clock configuration

Signed-off-by: Jan Kowalewski <jkowalewski@antmicro.com>
2 years agovendor.quicklogic: write OpenOCD scripts as part of build process.
whitequark [Fri, 13 Nov 2020 05:44:16 +0000 (05:44 +0000)]
vendor.quicklogic: write OpenOCD scripts as part of build process.

The OpenOCD scripts for EOS-S3 are roughly equivalent to SVF files
for a more traditional FPGA, which we also produce, for some common
"default" configuration, as a part of the build process.

2 years agobuild.plat: TemplatedPlatform.iter_extra_files→Platform.iter_files.
whitequark [Tue, 10 Nov 2020 05:30:21 +0000 (05:30 +0000)]
build.plat: TemplatedPlatform.iter_extra_files→Platform.iter_files.

This function was added in commit 20553b14 in the wrong place, with
the wrong name, and without tests. Fix all that.

2 years agohdl.rec: proxy operators correctly.
awygle [Mon, 9 Nov 2020 20:20:25 +0000 (12:20 -0800)]
hdl.rec: proxy operators correctly.

Commit abbebf8e used __getattr__ to proxy Value methods called on
Record. However, that did not proxy operators like __add__ because
Python looks up the special operator methods directly on the class
and does not run __getattr__ if they are missing.

Instead of using __getattr__, explicitly enumerate and wrap every
Value method that should be proxied. This also ensures backwards
compatibility if more methods are added to Value later.

Fixes #533.

2 years agovendor.intel: add support for Cyclone V internal oscillator
Konrad Beckmann [Fri, 6 Nov 2020 11:35:18 +0000 (12:35 +0100)]
vendor.intel: add support for Cyclone V internal oscillator

When using the default clock "cyclonev_oscillator" on Cyclone V devices,
the internal oscillator will be used.

2 years agohdl.ast: deprecate UserValue in favor of ValueCastable.
whitequark [Fri, 6 Nov 2020 02:21:53 +0000 (02:21 +0000)]
hdl.ast: deprecate UserValue in favor of ValueCastable.

Closes #527.

2 years agosim.pysim: avoid redundant VCD updates.
whitequark [Fri, 6 Nov 2020 02:05:35 +0000 (02:05 +0000)]
sim.pysim: avoid redundant VCD updates.

This commit properly addresses a bug introduced in 2efeb05c and then
temporarily fixed in 58f1d4bc.

Fixes #429.

2 years agoexamples: clean up oudated code.
whitequark [Fri, 6 Nov 2020 01:52:00 +0000 (01:52 +0000)]
examples: clean up oudated code.

2 years agoFix commit 8313d6e7.
whitequark [Fri, 6 Nov 2020 01:54:25 +0000 (01:54 +0000)]
Fix commit 8313d6e7.

2 years agocli: update deprecated import.
whitequark [Fri, 6 Nov 2020 01:39:04 +0000 (01:39 +0000)]
cli: update deprecated import.

2 years agoCI: add CPython 3.9 to test matrix.
whitequark [Fri, 6 Nov 2020 01:41:35 +0000 (01:41 +0000)]
CI: add CPython 3.9 to test matrix.

2 years agoCI: run testsuite with -Werror.
whitequark [Fri, 6 Nov 2020 01:38:03 +0000 (01:38 +0000)]
CI: run testsuite with -Werror.

2 years agovendor.lattice_{ice40,ecp5}: clean up $verilog_initial_trigger wires.
whitequark [Fri, 6 Nov 2020 01:31:14 +0000 (01:31 +0000)]
vendor.lattice_{ice40,ecp5}: clean up $verilog_initial_trigger wires.

These only matter in simulation and after conversion to Verilog.
During synthesis they cause Yosys to produce warnings:

  Warning: Wire $verilog_initial_trigger has an unprocessed 'init' attribute.

2 years agohdl.rec: migrate Record from UserValue to ValueCastable.
awygle [Fri, 6 Nov 2020 01:10:39 +0000 (17:10 -0800)]
hdl.rec: migrate Record from UserValue to ValueCastable.

Closes #528.

2 years agohdl.ast: implement ValueCastable.
awygle [Fri, 6 Nov 2020 00:20:54 +0000 (16:20 -0800)]
hdl.ast: implement ValueCastable.

Closes RFC issue #355.

2 years agovendor.quicklogic: part→package
whitequark [Thu, 5 Nov 2020 07:36:13 +0000 (07:36 +0000)]
vendor.quicklogic: part→package

2 years agovendor.xilinx_7series: byte swap generated bitstream
Norbert Braun [Mon, 2 Nov 2020 21:00:17 +0000 (22:00 +0100)]
vendor.xilinx_7series: byte swap generated bitstream

The Zynq driver in the FPGA Manager framework on Linux expects bitstreams that
are byte swapped with respect to what the Vivado command
`write_bitstream -bin_file` produces. Thus, use the `write_cfgmem` command with
appropriate options to generate the bitstream (.bin file).

Fixes #519.

2 years agolib.fifo: fix {r,w}_level in AsyncFIFOBuffered
Jaro Habiger [Tue, 18 Aug 2020 11:11:30 +0000 (13:11 +0200)]
lib.fifo: fix {r,w}_level in AsyncFIFOBuffered

2 years agolib.fifo: fix level on fifo full
Jaro Habiger [Tue, 3 Nov 2020 09:10:07 +0000 (10:10 +0100)]
lib.fifo: fix level on fifo full

2 years agovendor.lattice_ice40: zero-pad CLKHF_DIV in SB_HFOSC instance.
David Lattimore [Mon, 2 Nov 2020 06:19:47 +0000 (17:19 +1100)]
vendor.lattice_ice40: zero-pad CLKHF_DIV in SB_HFOSC instance.

Fixes #520.

2 years agovendor.quicklogic: utilize internal SoC clock in EOS-S3
Jan Kowalewski [Wed, 21 Oct 2020 12:24:41 +0000 (14:24 +0200)]
vendor.quicklogic: utilize internal SoC clock in EOS-S3

Signed-off-by: Jan Kowalewski <jkowalewski@antmicro.com>
2 years agovendor.quicklogic: fix toolchain nomenclature
Jan Kowalewski [Tue, 20 Oct 2020 10:46:58 +0000 (12:46 +0200)]
vendor.quicklogic: fix toolchain nomenclature

Signed-off-by: Jan Kowalewski <jkowalewski@antmicro.com>
2 years agolib.fifo.AsyncFFSynchronizer: check input and output signal width
Robin Ole Heinemann [Tue, 27 Oct 2020 23:41:01 +0000 (00:41 +0100)]
lib.fifo.AsyncFFSynchronizer: check input and output signal width

2 years agobuild.dsl: clean up inversion logic.
whitequark [Mon, 26 Oct 2020 19:50:21 +0000 (19:50 +0000)]
build.dsl: clean up inversion logic.

  * Add invert= argument to DiffPairs() constructor, like in Pins().
  * Make PinsN() and DiffPairsN() pass invert= to the corresponding
    construtor instead of mutating.

2 years agoback.{verilog,rtlil}: adjust $verilog_initial_trigger insertion.
whitequark [Sun, 25 Oct 2020 01:59:46 +0000 (01:59 +0000)]
back.{verilog,rtlil}: adjust $verilog_initial_trigger insertion.

To track upstream changes.

2 years agoCI: disable codecov project status.
whitequark [Sun, 25 Oct 2020 00:13:39 +0000 (00:13 +0000)]
CI: disable codecov project status.

Every PR should be covered by tests, and codecov patch statuses are
extremely useful. However, codecov project statuses mostly create
noise because project-wide coverage in nMigen is currently primarily
informational.

2 years agolib.fifo.AsyncFIFO: fix incorrect latency of r_level.
anuejn [Sat, 24 Oct 2020 14:58:23 +0000 (16:58 +0200)]
lib.fifo.AsyncFIFO: fix incorrect latency of r_level.

Co-authored-by: Andrew Wygle <awygle@gmail.com>
2 years agotests: make spec directory name unique per test method.
anuejn [Thu, 22 Oct 2020 21:38:44 +0000 (23:38 +0200)]
tests: make spec directory name unique per test method.

2 years agosim._pyrtl: sign extend RHS of assignment.
whitequark [Thu, 22 Oct 2020 16:08:38 +0000 (16:08 +0000)]
sim._pyrtl: sign extend RHS of assignment.

Fixes #502.

2 years agohdl.dsl: error on Elif immediately nested in an If.
whitequark [Thu, 22 Oct 2020 13:23:06 +0000 (13:23 +0000)]
hdl.dsl: error on Elif immediately nested in an If.

I.e. on this code, which is currently not only wrongly accepted but
also results in completely unexpected RTL:

    with m.If(...):
        with m.Elif(...):
            ...

Fixes #500.

2 years agovendor.quicklogic: fix syntax
Jan Kowalewski [Mon, 19 Oct 2020 10:09:50 +0000 (12:09 +0200)]
vendor.quicklogic: fix syntax

Signed-off-by: Jan Kowalewski <jkowalewski@antmicro.com>
2 years agosetup.py: Exclude "tests" package
Luke Kenneth Casson Leighton [Fri, 31 Dec 2021 15:14:37 +0000 (15:14 +0000)]
setup.py: Exclude "tests" package

67b957d moved the tests from nmigen/test/ to tests/, and removed the
exclude= parameter from find_packages() in setup.py. However, even if
the new location is not inside the module tree, it is still found by
find_packages(), resulting in a stray "tests" module on the system.

2 years agohdl.ir: Update error message for Instance arguments
Xiretza [Fri, 16 Oct 2020 16:36:56 +0000 (18:36 +0200)]
hdl.ir: Update error message for Instance arguments

48d4ee4 added the option to specify attributes using Instance arguments,
but the error message wasn't updated accordingly.

2 years agoREADME: Quicklogic EOS S3 is now supported.
whitequark [Thu, 15 Oct 2020 18:10:39 +0000 (18:10 +0000)]
README: Quicklogic EOS S3 is now supported.

2 years agoCI: fix code coverage collection.
whitequark [Thu, 15 Oct 2020 18:09:04 +0000 (18:09 +0000)]
CI: fix code coverage collection.

This has been broken since commit d71e19e2 (2020-07-22).

2 years agovendor.quicklogic: new platform.
Jan Kowalewski [Thu, 15 Oct 2020 18:02:25 +0000 (20:02 +0200)]
vendor.quicklogic: new platform.

Signed-off-by: Kamil Rakoczy <krakoczy@antmicro.com>
Signed-off-by: Jan Kowalewski <jkowalewski@antmicro.com>
Co-authored-by: Kamil Rakoczy <krakoczy@antmicro.com>
2 years agotests: keep comments up to date. NFC.
whitequark [Thu, 15 Oct 2020 17:02:50 +0000 (17:02 +0000)]
tests: keep comments up to date. NFC.

2 years agobuild.plat: avoid type confusion in _check_feature.
whitequark [Thu, 15 Oct 2020 08:54:48 +0000 (08:54 +0000)]
build.plat: avoid type confusion in _check_feature.

Before this commit, `_check_feature(valid_xdrs=0)` would mean that
XDR buffers are not supported. Only `_check_feature(valid_xdrs=())`
was intended to be an indicator of that.

2 years agohdl.mem: document ReadPort and WritePort.
Jean-François Nguyen [Tue, 15 Sep 2020 00:20:35 +0000 (02:20 +0200)]
hdl.mem: document ReadPort and WritePort.

Fixes #496.

2 years agovendor.lattice_{ecp5,machxo_2_3l}: explain how to set up NMIGEN_ENV_Diamond on Windows.
William D. Jones [Sat, 29 Aug 2020 19:34:57 +0000 (15:34 -0400)]
vendor.lattice_{ecp5,machxo_2_3l}: explain how to set up NMIGEN_ENV_Diamond on Windows.

2 years agoback.verilog: use `proc -nomux` if it is available.
whitequark [Thu, 27 Aug 2020 13:03:15 +0000 (13:03 +0000)]
back.verilog: use `proc -nomux` if it is available.

Yosys offers no stability guarantees for individual `proc_*` passes,
though so far it worked out fine. This commit changes the Verilog
backend to use `proc -nomux` instead, which is guaranteed to have
backwards-compatible behavior.

Fixes #479.

2 years agosim: split into base, core, and engines.
whitequark [Thu, 27 Aug 2020 10:17:02 +0000 (10:17 +0000)]
sim: split into base, core, and engines.

Before this commit, each simulation engine (which is only pysim at
the moment, but also cxxsim soon) was a subclass of SimulatorCore,
and every simulation engine module would essentially duplicate
the complete structure of a simulator, with code partially shared.

This was a really bad idea: it was inconvenient to use, with
downstream code having to branch between e.g. PySettle and CxxSettle;
it had no well-defined external interface; it had multiple virtually
identical entry points; and it had no separation between simulation
algorithms and glue code.

This commit completely rearranges simulation code.
  1. sim._base defines internal simulation interfaces. The clarity of
     these internal interfaces is important because simulation
     engines mix and match components to provide a consistent API
     regardless of the chosen engine.
  2. sim.core defines the external simulation interface: the commands
     and the simulator facade. The facade provides a single entry
     point and, when possible, validates or lowers user input.
     It also imports built-in simulation engines by their symbolic
     name, avoiding eager imports of pyvcd or ctypes.
  3. sim.xxxsim (currently, only sim.pysim) defines the simulator
     implementation: time and state management, process scheduling,
     and waveform dumping.

The new simulator structure has none of the downsides of the old one.

See #324.

2 years agosim.pysim: in write_vcd(), close files if an exception is raised.
whitequark [Thu, 27 Aug 2020 08:33:48 +0000 (08:33 +0000)]
sim.pysim: in write_vcd(), close files if an exception is raised.

This also avoids leaving the waveform writer list in an inconsistent
state after an exception.

2 years agosim._pyclock: new type of process.
whitequark [Thu, 27 Aug 2020 07:54:27 +0000 (07:54 +0000)]
sim._pyclock: new type of process.

The overhead of coroutine processes is fairly high. A clock driver
implemented through a coroutine process is mostly overhead. This was
partially addressed in commit 2398b792 by microoptimizing yielding.

This commit eliminates the coroutine process overhead completely by
introducing dedicated clock processes. It also simplifies the logic
to a simple toggle.

This change improves runtime by about 12% on Minerva SRAM SoC.

2 years agosim._pycoro: make src_loc() more robust.
whitequark [Thu, 27 Aug 2020 07:11:14 +0000 (07:11 +0000)]
sim._pycoro: make src_loc() more robust.

  * Guard for finished coroutines.
  * Guard for coroutines yielding from iterators and not generators.

2 years ago_toolchain.cxx: work around PyPy missing LDCXXSHARED sysconfig variable.
whitequark [Thu, 27 Aug 2020 06:53:14 +0000 (06:53 +0000)]
_toolchain.cxx: work around PyPy missing LDCXXSHARED sysconfig variable.

2 years ago_toolchain.cxx: new toolchain.
whitequark [Thu, 27 Aug 2020 06:24:18 +0000 (06:24 +0000)]
_toolchain.cxx: new toolchain.

2 years agohdl.ast: clarify exception message for out of bounds indexing.
whitequark [Thu, 27 Aug 2020 01:14:05 +0000 (01:14 +0000)]
hdl.ast: clarify exception message for out of bounds indexing.

Fixes #488.

2 years agonmigen.test.utils: restore FHDLTestCase to gracefully deprecate it.
whitequark [Thu, 27 Aug 2020 00:46:50 +0000 (00:46 +0000)]
nmigen.test.utils: restore FHDLTestCase to gracefully deprecate it.

Fixes #484.

2 years agoremove exclude tests in setup.py
Luke Kenneth Casson Leighton [Fri, 31 Dec 2021 15:09:50 +0000 (15:09 +0000)]
remove exclude tests in setup.py

2 years agotests: move out of the main package.
whitequark [Thu, 27 Aug 2020 00:33:31 +0000 (00:33 +0000)]
tests: move out of the main package.

Compared to tests in the repository root, tests in the package have
many downsides:
  * Unless explicitly excluded in find_packages(), tests and their
    support code effectively become a part of public API.
    This, unfortunately, happened with FHDLTestCase, which was never
    intended for downstream use.
  * Even if explicitly excluded from the setuptools package, using
    an editable install, or setting PYTHONPATH still allows accessing
    the tests.
  * Having a sub-package that is present in the source tree but not
    exported (or, worse, exported only sometimes) is confusing.
  * The name `nmigen.test` cannot be used for anything else, such as
    testing utilities that *are* intended for downstream use.

2 years agoadd paramiko extras
Luke Kenneth Casson Leighton [Fri, 31 Dec 2021 15:08:09 +0000 (15:08 +0000)]
add paramiko extras

2 years agobuild.run: implement SSH remote builds using Paramiko.
William D. Jones [Wed, 26 Aug 2020 22:49:49 +0000 (18:49 -0400)]
build.run: implement SSH remote builds using Paramiko.

2 years agoback.rtlil: do not squash empty modules.
whitequark [Wed, 26 Aug 2020 22:45:19 +0000 (22:45 +0000)]
back.rtlil: do not squash empty modules.

In commit 9faa1d37, the RTLIL backend was changed to ignore modules
without ports completely, since Yosys would recognize empty modules
as black boxes without explicit `write_verilog -noblackbox` and break
the design. That change had many flaws:
  * It removed instances without ports, which are used in e.g. SoC
    FPGAs to instantiate a dummy CPU.
  * It removed fragments without ports, which can appear in e.g. SoC
    FPGAs in case the fabric is not connected to any I/O ports.
  * Finally, it was just conceptually unjustified.

This commit changes the logic to actually check for empty fragments,
and instead of removing them, it adds a dummy wire inside. It would
be possible to use the Yosys-specific (*noblackbox*) attribute.
However, it would be necessary to strip it for most targets right
away, and also the wire doubles as documentation.

Fixes #441.

2 years agoback.verilog: omit Verilog initial trigger only if Yosys adds it.
whitequark [Wed, 26 Aug 2020 09:01:57 +0000 (09:01 +0000)]
back.verilog: omit Verilog initial trigger only if Yosys adds it.

Verilog has an edge case where an `always @*` process, which is used
to describe a combinatorial function procedurally, may not execute
at time zero because none of the signals in its implicit sensitivity
list change, i.e. when the process doesn't read any signals. This
causes the wires driven by the process to stay undefined.

The workaround to this problem (assuming SystemVerilog `always_comb`
is not available) is to introduce a dummy signal that changes only
at time zero and is optimized out during synthesis. nMigen has had
its own workaround, `$verilog_initial_trigger`, for a while. However,
`proc_prune`, while increasing readability, pulls references to this
signal out of the process. Because of this, a similar workaround was
implemented in Yosys' `write_verilog` itself.

This commit ensures we use our workaround on versions of Yosys
without the updated `write_verilog`, and Yosys' workaround on later
versions.

Fixes #418.

2 years agovendor.xilinx_{7series,ultrascale}: set BUFG* SIM_DEVICE as appropriate.
whitequark [Wed, 26 Aug 2020 10:18:02 +0000 (10:18 +0000)]
vendor.xilinx_{7series,ultrascale}: set BUFG* SIM_DEVICE as appropriate.

Fixes #438 (again).

2 years agovendor.xilinx_7series: unbreak.
whitequark [Wed, 26 Aug 2020 14:57:31 +0000 (14:57 +0000)]
vendor.xilinx_7series: unbreak.

This commit fixes a series of typos introduced in commit 4e208b0a.

2 years agosim._pyrtl: optimize uses of reflexive operators.
whitequark [Wed, 26 Aug 2020 13:26:38 +0000 (13:26 +0000)]
sim._pyrtl: optimize uses of reflexive operators.

When a literal is used on the left-hand side of a numeric operator,
Python is able to constant-fold some expressions:

    >>> dis.dis(lambda x: 0 + 0 + x)
      1           0 LOAD_CONST               1 (0)
                  2 LOAD_FAST                0 (x)
                  4 BINARY_ADD
                  6 RETURN_VALUE

If a literal is used on the right-hand side such that the left-hand
side is variable, this doesn't happen:

    >>> dis.dis(lambda x: x + 0 + 0)
      1           0 LOAD_FAST                0 (x)
                  2 LOAD_CONST               1 (0)
                  4 BINARY_ADD
                  6 LOAD_CONST               1 (0)
                  8 BINARY_ADD
                 10 RETURN_VALUE

PyRTL generates fairly redundant code due to the pervasive masking,
and because of that, transforming expressions into the former form,
where possible, improves runtime by about 10% on Minerva SRAM SoC.

2 years agoback.cxxrtl: actualize Yosys version requirement.
whitequark [Wed, 26 Aug 2020 09:16:46 +0000 (09:16 +0000)]
back.cxxrtl: actualize Yosys version requirement.

2 years agohdl.ast: avoid unnecessary sign padding in ArrayProxy.
whitequark [Wed, 26 Aug 2020 06:58:22 +0000 (06:58 +0000)]
hdl.ast: avoid unnecessary sign padding in ArrayProxy.

Before this commit, ArrayProxy would add sign padding (an extra bit)
a homogeneous array of signed values, or an array where all unsigned
values are smaller than the largest signed one. After this commit,
ArrayProxy would only add padding in arrays with mixed signedness
where all signed values are smaller or equal in size to the largest
unsigned value.

Fixes #476.

Co-authored-by: Pepijn de Vos <pepijndevos@gmail.com>
2 years agosim._pyrtl: fix miscompilation of -(Const(0b11, 2).as_signed()).
whitequark [Wed, 26 Aug 2020 04:15:26 +0000 (04:15 +0000)]
sim._pyrtl: fix miscompilation of -(Const(0b11, 2).as_signed()).

Fixes #473.

2 years agolib.cdc: in AsyncFFSynchronizer(), rename domain= to
Luke Kenneth Casson Leighton [Fri, 31 Dec 2021 15:03:02 +0000 (15:03 +0000)]
lib.cdc: in AsyncFFSynchronizer(), rename domain= to
 o_domain=.

This is for consistency with other synchronizers.

Fixes #467.

2 years agovendor.lattice_machxo_2_3l: add SRAM svf generation
Robin Ole Heinemann [Tue, 4 Aug 2020 15:30:18 +0000 (17:30 +0200)]
vendor.lattice_machxo_2_3l: add SRAM svf generation

2 years agovendor: Add initial support for Symbiflow for Xilinx 7-series
Mariusz Glebocki [Sun, 2 Aug 2020 16:48:26 +0000 (18:48 +0200)]
vendor: Add initial support for Symbiflow for Xilinx 7-series

2 years agovendor.xilinx_7series: add `_part` property getter
Mariusz Glebocki [Mon, 24 Aug 2020 11:03:59 +0000 (13:03 +0200)]
vendor.xilinx_7series: add `_part` property getter

2 years agocli: Improve help texts
Xiretza [Sat, 22 Aug 2020 13:46:58 +0000 (15:46 +0200)]
cli: Improve help texts

545e49c2 added the option to export as CXXRTL, but the help texts for
the CLI options don't reflect this yet.

2 years agodocs/lang: use less confusing placeholder variable names.
whitequark [Sat, 15 Aug 2020 13:00:50 +0000 (13:00 +0000)]
docs/lang: use less confusing placeholder variable names.

Fixes #474.

2 years agolib.fifo: add `r_level` and `w_level` to all FIFOs
awygle [Sat, 15 Aug 2020 08:40:56 +0000 (01:40 -0700)]
lib.fifo: add `r_level` and `w_level` to all FIFOs

2 years agoAdd Linguist tags to .gitattributes.
whitequark [Thu, 13 Aug 2020 03:10:17 +0000 (03:10 +0000)]
Add Linguist tags to .gitattributes.

This should make it possible to navigate to nmigen/vendor/*.py using
GitHub's file finder.

2 years agovendor.lattice_{ecp5,machxo_2_3l}: specify impl-dir correctly
Robin Ole Heinemann [Mon, 10 Aug 2020 15:23:29 +0000 (17:23 +0200)]
vendor.lattice_{ecp5,machxo_2_3l}: specify impl-dir correctly

2 years agobuild,vendor: never carry around parts of differential signals.
whitequark [Fri, 31 Jul 2020 13:17:39 +0000 (13:17 +0000)]
build,vendor: never carry around parts of differential signals.

When a port component is skipped, it should appear neither in the RTL
nor in the constraint file. However, passing around components of
differential ports explicitly makes that harder.

Fixes #456.
Supersedes #457.

Co-authored-by: Jean THOMAS <git0@pub.jeanthomas.me>
2 years agovendor.xilinx_{7series,ultrascale}: use BUFGCTRL rather than BUFGCE.
whitequark [Fri, 31 Jul 2020 14:45:38 +0000 (14:45 +0000)]
vendor.xilinx_{7series,ultrascale}: use BUFGCTRL rather than BUFGCE.

Fixes #438 (again).

2 years agohdl.mem: cast reset value for transparent read ports to integer.
Adam Greig [Thu, 30 Jul 2020 07:05:18 +0000 (08:05 +0100)]
hdl.mem: cast reset value for transparent read ports to integer.

2 years agonmigen.lib.scheduler: add RoundRobin.
Jean THOMAS [Tue, 28 Jul 2020 21:02:01 +0000 (23:02 +0200)]
nmigen.lib.scheduler: add RoundRobin.