WIP Compressed bitstream support - #1
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Signed-off-by: Hans Baier <hansfbaier@gmail.com>
Signed-off-by: Hans Baier <hansfbaier@gmail.com>
…duces specimens to 40 Signed-off-by: Hans Baier <hansfbaier@gmail.com>
…e banks Signed-off-by: Hans Baier <hansfbaier@gmail.com>
Signed-off-by: Hans Baier <hansfbaier@gmail.com>
…4pga#2075) Bumps [third_party/abseil-cpp](https://github.com/abseil/abseil-cpp) from `522606b` to `71927b4`. - [Release notes](https://github.com/abseil/abseil-cpp/releases) - [Commits](abseil/abseil-cpp@522606b...71927b4) --- updated-dependencies: - dependency-name: third_party/abseil-cpp dependency-type: direct:production ... Signed-off-by: dependabot[bot] <support@github.com> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
…4pga#2074) Bumps [third_party/googletest](https://github.com/google/googletest) from `1f643f7` to `3fa7f98`. - [Release notes](https://github.com/google/googletest/releases) - [Commits](google/googletest@1f643f7...3fa7f98) --- updated-dependencies: - dependency-name: third_party/googletest dependency-type: direct:production ... Signed-off-by: dependabot[bot] <support@github.com> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
various fixes for 030-iob18
…a#2079) Bumps [third_party/yosys](https://github.com/YosysHQ/yosys) from `7ad7b55` to `3ebc50d`. - [Release notes](https://github.com/YosysHQ/yosys/releases) - [Commits](YosysHQ/yosys@7ad7b55...3ebc50d) --- updated-dependencies: - dependency-name: third_party/yosys dependency-type: direct:production ... Signed-off-by: dependabot[bot] <support@github.com> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
…4pga#2081) Bumps [third_party/abseil-cpp](https://github.com/abseil/abseil-cpp) from `71927b4` to `6abc195`. - [Release notes](https://github.com/abseil/abseil-cpp/releases) - [Commits](abseil/abseil-cpp@71927b4...6abc195) --- updated-dependencies: - dependency-name: third_party/abseil-cpp dependency-type: direct:production ... Signed-off-by: dependabot[bot] <support@github.com> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Bumps [third_party/sanitizers-cmake](https://github.com/arsenm/sanitizers-cmake) from `99e159e` to `a6748f4`. - [Release notes](https://github.com/arsenm/sanitizers-cmake/releases) - [Commits](arsenm/sanitizers-cmake@99e159e...a6748f4) --- updated-dependencies: - dependency-name: third_party/sanitizers-cmake dependency-type: direct:production ... Signed-off-by: dependabot[bot] <support@github.com> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
…a#2083) Bumps [third_party/yosys](https://github.com/YosysHQ/yosys) from `3ebc50d` to `f2c6894`. - [Release notes](https://github.com/YosysHQ/yosys/releases) - [Commits](YosysHQ/yosys@3ebc50d...f2c6894) --- updated-dependencies: - dependency-name: third_party/yosys dependency-type: direct:production ... Signed-off-by: dependabot[bot] <support@github.com> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
…4pga#2085) Bumps [third_party/abseil-cpp](https://github.com/abseil/abseil-cpp) from `6abc195` to `625a180`. - [Release notes](https://github.com/abseil/abseil-cpp/releases) - [Commits](abseil/abseil-cpp@6abc195...625a180) --- updated-dependencies: - dependency-name: third_party/abseil-cpp dependency-type: direct:production ... Signed-off-by: dependabot[bot] <support@github.com> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
…a#2088) Bumps [third_party/yosys](https://github.com/YosysHQ/yosys) from `f2c6894` to `956c4e4`. - [Release notes](https://github.com/YosysHQ/yosys/releases) - [Commits](YosysHQ/yosys@f2c6894...956c4e4) --- updated-dependencies: - dependency-name: third_party/yosys dependency-type: direct:production ... Signed-off-by: dependabot[bot] <support@github.com> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
…4pga#2087) Bumps [third_party/googletest](https://github.com/google/googletest) from `3fa7f98` to `356fc30`. - [Release notes](https://github.com/google/googletest/releases) - [Commits](google/googletest@3fa7f98...356fc30) --- updated-dependencies: - dependency-name: third_party/googletest dependency-type: direct:production ... Signed-off-by: dependabot[bot] <support@github.com> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
…4pga#2086) Bumps [third_party/abseil-cpp](https://github.com/abseil/abseil-cpp) from `625a180` to `bb63a76`. - [Release notes](https://github.com/abseil/abseil-cpp/releases) - [Commits](abseil/abseil-cpp@625a180...bb63a76) --- updated-dependencies: - dependency-name: third_party/abseil-cpp dependency-type: direct:production ... Signed-off-by: dependabot[bot] <support@github.com> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
…a#2092) Bumps [third_party/yosys](https://github.com/YosysHQ/yosys) from `956c4e4` to `611f71c`. - [Release notes](https://github.com/YosysHQ/yosys/releases) - [Commits](YosysHQ/yosys@956c4e4...611f71c) --- updated-dependencies: - dependency-name: third_party/yosys dependency-type: direct:production ... Signed-off-by: dependabot[bot] <support@github.com> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
…4pga#2091) Bumps [third_party/googletest](https://github.com/google/googletest) from `356fc30` to `ec25eea`. - [Release notes](https://github.com/google/googletest/releases) - [Commits](google/googletest@356fc30...ec25eea) --- updated-dependencies: - dependency-name: third_party/googletest dependency-type: direct:production ... Signed-off-by: dependabot[bot] <support@github.com> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
…4pga#2090) Bumps [third_party/abseil-cpp](https://github.com/abseil/abseil-cpp) from `bb63a76` to `4eef161`. - [Release notes](https://github.com/abseil/abseil-cpp/releases) - [Commits](abseil/abseil-cpp@bb63a76...4eef161) --- updated-dependencies: - dependency-name: third_party/abseil-cpp dependency-type: direct:production ... Signed-off-by: dependabot[bot] <support@github.com> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Signed-off-by: Lakira Ashley <lakridesagain@gmail.com>
Signed-off-by: Lakira Ashley <lakridesagain@gmail.com>
Signed-off-by: Lakira Ashley <lakridesagain@gmail.com>
Signed-off-by: Lakira Ashley <lakridesagain@gmail.com>
colin-rushton-qss
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Aug 15, 2026
Every full bitstream this writer emits is a CRC-DISABLED bitstream, and
nothing said so. createConfigurationPackage()'s finalization sequence puts
two CMD:RCRC writes in the two positions where a Vivado full bitstream puts
two writes to the CRC register:
... frame data ... CRC <= v1 CMD:GRESTORE CMD:DGHIGH
CMD:START FAR <= 0x03be0000 MASK CTL0 CRC <= v2 CMD:DESYNC
Read out of Vivado 2025.2's own pt_v2_soc_fn.bit for 7a100tfgg484: two CRC
words, 0x10c41b1c and 0x615009a6, in exactly those two slots. Substituting
CMD:RCRC for each is not a different stream shape -- it is bit-for-bit what
BITSTREAM.GENERAL.CRC=DISABLE does, the same two-word substitution the
partial path already documents (0x30000001,<crc> <-> 0x30008001,0x00000007).
So the device's own configuration-integrity check never runs on anything
this tool writes, and the cost of that is measured rather than argued. On
an XC7A100T (Alchitry Pt V2, fgg484), a single flipped configuration bit in
a 3.8 MB stream -- one byte, one bit, with the frame ECC left stale --
loaded to DONE=1 with "No CRC error" and "No ID error", and the resulting
design ran at 11,525.6 B/s against a same-board control of 292.5 B/s. One
bit, accepted, 39x wrong.
--emit_crc replaces each of those two CMD:RCRC writes, in place, with a
Type-1 write of computeStreamCrc() over everything that precedes it.
computeStreamCrc() is the existing Series7 model added for the partial path:
reflected CRC-32C (0x82F63B78), data[31:0] then addr[4:0] LSB-first, every
register write accumulated except a write to the CRC register, a CRC write
resets the accumulator, CMD:RCRC resets and consumes its own write. It is
called at the moment of emission rather than precomputed, because a CRC
write is itself a reset and the second value therefore covers only what
follows the first.
Evidence that the value is right and not merely plausible: the same model,
replayed by an independent implementation, reproduces BOTH of Vivado's own
full-bitstream CRC words on this die (2/2) and its partial-bitstream CRC on
three reference modules (1/1 in 3 of 3). Emitting a 3.8 MB bitstream with
--emit_crc and replaying it gives 2 CRC words, 2/2 observed == computed;
flipping one configuration bit in the frame data gives 1/2, with the first
CRC mismatching and the second -- which accumulates nothing before it --
still matching.
OFF BY DEFAULT, and that is a decision rather than caution. Turning it on
changes the payload of every full bitstream the toolchain builds, and
hundreds of recorded payload hashes identify artefacts by exactly that
payload. Measured: without the flag, this build reproduces an existing
3,825,977-byte artefact byte-for-byte from the sync word
(bde03029d76fcff4cbdcf8c0ffbfd010e1493f3df40adba98a7b0bc3ebf292a3); with
it, 4 of 956,435 payload words move and they are the two substitutions.
--crc {compute,disable} keeps steering the PARTIAL path only and its help
text now says so. --emit_crc together with --partial_bitstream is refused
rather than ignored: a flag that silently does nothing is a check that
never runs.
createConfigurationPackage() gains a `bool emit_crc` parameter on all four
architecture specializations. xc7patch passes false, so its output does not
move.
Three tests, in lib/xilinx/tests/xc7series/configuration_test.cc:
FullPackageCrcEmissionIsATwoWordSubstitution -- with and against without,
exactly 2 register-sequence entries differ, each CRC against
CMD:RCRC; the CRC-disabled package still carries 3 CMD:RCRC writes
and the CRC-enabled one carries 1.
FullPackageCrcIsTheAccumulatorAtEachWrite -- each emitted CRC equals
computeStreamCrc() of the packets that precede it, there are exactly
two, and they differ from each other.
FullPackageCrcMovesWhenOneFrameWordMoves -- flip one bit of frame data:
CRC openXC7#1 must move and CRC openXC7#2 must not.
The last two were seen to FAIL, not merely to pass: replacing the computed
value with a constant leaves the substitution test green and turns both of
the others red, which is the split of duties they were written to have.
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This is a temporary PR to run the CI for f4pga#2060