CSR: move custom performance counters off standard HPM space - #281
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The custom counters occupied mhpmcounter addresses. Relocate them to CustomPerfCntBase1 (0x7c0) and CustomPerfCntBase2 (0xbc0) and make them unwritable. Leave mcycle and minstret at the standard addresses as independent registers. A CSR write takes priority over the automatic increment. The pendingSReq update wrote perfCnts(0xb65) from perfCnts(0xb66).
poemonsense
approved these changes
Sep 20, 2026
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The custom counters occupied mhpmcounter addresses. Relocate them to CustomPerfCntBase1 (0x7c0) and CustomPerfCntBase2 (0xbc0) and make them unwritable.
Leave mcycle and minstret at the standard addresses as independent registers. A CSR write takes priority over the automatic increment.
The pendingSReq update wrote perfCnts(0xb65) from perfCnts(0xb66).