[rtl] Reduce the lockstep delay to 1 cycle#2363
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nasahlpa wants to merge 4 commits intolowRISC:masterfrom
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[rtl] Reduce the lockstep delay to 1 cycle#2363nasahlpa wants to merge 4 commits intolowRISC:masterfrom
nasahlpa wants to merge 4 commits intolowRISC:masterfrom
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Move and reword this comment as it makes more sense at the line where we actually enable the lockstep comparison. Signed-off-by: Pascal Nasahl <nasahlpa@lowrisc.org>
This enables us to switch between different lockstep delays more easily. Signed-off-by: Pascal Nasahl <nasahlpa@lowrisc.org>
This commit reduces the lockstep delay from two cycles to one cycle to reduce the area overhead of the lockstep. For this, the RTL is adapted such that `LockstepOffset = 1` works, which was not the case before. Signed-off-by: Pascal Nasahl <nasahlpa@lowrisc.org>
Two fixes: - When `LockstepOffset = 1`, the `u_rst_shadow_cnt` instance does not exist. - Fix the `u_rst_shadow_cnt` instance path as it is now in `gen_reset_counter`. Signed-off-by: Pascal Nasahl <nasahlpa@lowrisc.org>
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Before this PR, a lockstep delay of 2 cycles was used when the lockstep mechanism was active (which is the case when
SecureIbex = 1). This PR reduces the delay to 1 cycle to save area.