Philippe Mathieu-Daudé <phi...@linaro.org> writes:
> Some CPU features aren't strictly required to run guest code (such > debugging features), so we don't model them. To prevent the guest > to access non-existent system registers, we disable the feature bit > in the ID registers (see commit 7d8c283e10 "target/arm: Suppress more > TCG unimplemented features in ID registers"). > > Since it might be useful to know when a CPU supposed to implement a > feature has it disabled in QEMU, provide the ability to log disabled > features at the UNIMP level: > > $ qemu-system-aarch64 -M virt -d unimp -S -cpu neoverse-v1 > QEMU 8.0.92 monitor - type 'help' for more information > CPU#0: Disabling unimplemented feature 'FEAT_SPE (Statistical Profiling > Extension)' for neoverse-v1 > CPU#0: Disabling unimplemented feature 'FEAT_TRF (Self-hosted Trace > Extension)' for neoverse-v1 > CPU#0: Disabling unimplemented feature 'FEAT_TRF (Self-hosted Trace > Extension)' for neoverse-v1 > CPU#0: Disabling unimplemented feature 'Trace Macrocell system register > access' for neoverse-v1 > CPU#0: Disabling unimplemented feature 'Trace Macrocell system register > access' for neoverse-v1 > CPU#0: Disabling unimplemented feature 'Memory-mapped Trace' for > neoverse-v1 Don't these also depend on FEAT_? Otherwise: Reviewed-by: Alex Bennée <alex.ben...@linaro.org> -- Alex Bennée Virtualisation Tech Lead @ Linaro
