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Generally, hardware performance counters can only be started, stopped, or configured from machine-mode using mcountinhibit and mhpmeventX CSRs. Also, in opensbi only sbi_pmu_ctr_cfg_match() managed mhpmeventX. But in generic Linux driver, when perf starts, Linux calls both sbi_pmu_ctr_cfg_match() and sbi_pmu_ctr_start(), while after hart suspend only sbi_pmu_ctr_start() command called through SBI interface. This doesn't work properly in case when suspend state resets HPM registers. In order to keep counter integrity, sbi_pmu_ctr_start() modified. First, we're saving hw_counters_data, and after hart suspend this value is restored if event is currently active. Signed-off-by: Alexander Chuprunov <alexander.chuprunov@syntacore.com> Reviewed-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20250918090706.2217603-2-alexander.chuprunov@syntacore.com Signed-off-by: Anup Patel <anup@brainfault.org>