[NFC] Refine assertion to be robust to clk / rst event coincidence#33
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micprog merged 1 commit intopulp-platform:mainfrom Apr 15, 2026
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This patch fixes a reset glitch in the `lock_req` assertion. Previously, the assertion used `lock_d` as an antecedant of the assertion in the next cycle. Since IEEE 1800 does not guarantee the resolution of zero-delay updates, whenever the clock edge of `clk_i` coincides with the deassertion of `rst_ni` `lock_d` might be in any state, since it combinationally depends on inputs of the cache. This can lead to the assertion wrongfully triggering a cycle after reset. To fix this, this patch uses the latched `lock_q` an assumes the antecedant to hold in the same cycle instead. This leads to no functional changes, but avoids the zero-delay issue.
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This patch fixes a reset glitch in the
lock_reqassertion. Previously, the assertion usedlock_das an antecedant of the assertion in the next cycle. Since IEEE 1800 does not guarantee the resolution of zero-delay updates in any particular order, whenever the clock edge ofclk_icoincides with the deassertion ofrst_nilock_dmight be in any state, since it combinationally depends on inputs of the cache. This can lead to the assertion wrongfully triggering a cycle after reset.To fix this, this patch uses the latched
lock_qan assumes the antecedant to hold in the same cycle instead. This leads to no functional changes, but avoids the zero-delay issue.