Don't randomly init SRAM when testing lightweight "test ROMs" #1407
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korran
requested review from
fdamato,
jlmahowa-amd,
mhatrevi,
jhand2,
ajisaxena,
vsonims,
JohnTraverAmd and
rusty1968
as code owners
To improve verilator times, caliptra-test-harness does not initialize SRAM contents, so we must run our tests with the memory cleared to zeroes, in case the compiler generates a speculative read to uninitialized memory (this is rare, but tricky to debug when it happens). PR chipsalliance#1404 tweaks one of these test binaries enough that the compiler generates a speculative read to uninitialized memory, which intermittently triggers an ECC double-bit error.
jlmahowa-amd
approved these changes
Mar 18, 2024
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To improve verilator times, caliptra-test-harness does not initialize SRAM contents,
PR #1404 tweaks one of these test binaries enough that the compiler generates a speculative read to uninitialized memory, which intermittently triggers an ECC double-bit error.
To prevent this from happening, we must run lightweight tests with the memory cleared to zeroes, in case the compiler generates a speculative read to uninitialized memory (this is rare, but tricky to debug when it happens).