[v1 2/2] lib: sbi_pmu: Fix the counter info function

[Xiang W]

在 2023-12-05星期二的 17:08 -0800，Atish Patra写道：
> The counter info should only return valid hardware counters for the ones
> set in the counter mask. Otherwise, it will report incorrect number of
> hardware counters to the supervisor if the platform has discontiguous
> counters.
> 
> Fixes: c744ed77b18c ("lib: sbi_pmu: Enable noncontigous hpm event and counters")
> 
> Signed-off-by: Atish Patra <atishp at rivosinc.com>
> ---
>  lib/sbi/sbi_pmu.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/lib/sbi/sbi_pmu.c b/lib/sbi/sbi_pmu.c
> index 185068bb1f43..ac5ae0af7da4 100644
> --- a/lib/sbi/sbi_pmu.c
> +++ b/lib/sbi/sbi_pmu.c
> @@ -885,6 +885,7 @@ int sbi_pmu_ctr_get_info(uint32_t cidx, unsigned long *ctr_info)
>  	int width;
>  	union sbi_pmu_ctr_info cinfo = {0};
>  	struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
> +	unsigned long counter_mask = (unsigned long)sbi_hart_mhpm_mask(scratch) | 0x5;
>  
>  	/* Sanity check. Counter1 is not mapped at all */
>  	if (cidx >= total_ctrs || cidx == 1)
Because counter_mask does not contain counter1, the cidx==1 check can be removed here.

Regards,
Xiang W

> @@ -892,6 +893,8 @@ int sbi_pmu_ctr_get_info(uint32_t cidx, unsigned long *ctr_info)
>  
>  	/* We have 31 HW counters with 31 being the last index(MHPMCOUNTER31) */
>  	if (cidx < num_hw_ctrs) {
> +		if (!(__test_bit(cidx, &counter_mask)))
> +			return SBI_EINVAL;
>  		cinfo.type = SBI_PMU_CTR_TYPE_HW;
>  		cinfo.csr = CSR_CYCLE + cidx;
>  		/* mcycle & minstret are always 64 bit */
> -- 
> 2.34.1
> 
>