tc_sram: Guard simulation-only random init from synthesis#46
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The `random_init_word` function uses `$urandom`, which synthesis tools cannot elaborate inside a function body (e.g. Synopsys DC fails with VER-110). Move the `init_val` declaration out so it stays visible as the SRAM reset value, and guard the function and the init process with `pragma translate_off`/`translate_on`. Simulators ignore the pragma, so simulation behavior is unchanged.
Collaborator
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What exactly is the scenario where one would synthesize the generic tc_sram? |
Author
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Sorry for the confusion, it's not actually synthesized. Our DC flow only passes |
Collaborator
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We would have to test if this works properly (it should) but maybe we could guard a |
Author
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Yes that would be great! |
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#44 moved the random initialization into the
random_init_wordfunction, so$urandomis now elaborated by synthesis tools. In AXI, when Bender automatically updatestech_cells_generictov0.2.14, Synopsys DC fails with VER-110.This PR moves the
init_valdeclaration out so it stays visible as the SRAM reset value, and guards the function and the init process withpragma translate_off/translate_on. Simulators ignore the pragma, so simulation behavior should be unchanged.This PR is verified in the AXI CI, with DC elaborating
tc_sramcleanly again, and the Questasim simulation passed.