On 22/03/2025 13:14, Andrew Jones wrote:
> On Mon, Mar 17, 2025 at 06:06:10PM +0100, Clément Léger wrote:
>> Add FWFT extension calls. This will be ratified in SBI V3.0 hence, it is
>> provided as a separate commit that can be left out if needed.
>>
>> Signed-off-by: Clément Léger <cleger@xxxxxxxxxxxx>
>> ---
>> arch/riscv/kernel/sbi.c | 30 ++++++++++++++++++++++++++++--
>> 1 file changed, 28 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/riscv/kernel/sbi.c b/arch/riscv/kernel/sbi.c
>> index d41a5642be24..54d9ceb7b723 100644
>> --- a/arch/riscv/kernel/sbi.c
>> +++ b/arch/riscv/kernel/sbi.c
>> @@ -299,6 +299,8 @@ static int __sbi_rfence_v02(int fid, const struct cpumask *cpu_mask,
>> return 0;
>> }
>>
>> +static bool sbi_fwft_supported;
>> +
>> /**
>> * sbi_fwft_get() - Get a feature for the local hart
>> * @feature: The feature ID to be set
>> @@ -308,7 +310,15 @@ static int __sbi_rfence_v02(int fid, const struct cpumask *cpu_mask,
>> */
>> int sbi_fwft_get(u32 feature, unsigned long *value)
>> {
>> - return -EOPNOTSUPP;
>> + struct sbiret ret;
>> +
>> + if (!sbi_fwft_supported)
>> + return -EOPNOTSUPP;
>> +
>> + ret = sbi_ecall(SBI_EXT_FWFT, SBI_EXT_FWFT_GET,
>> + feature, 0, 0, 0, 0, 0);
>
> We're missing the
>
> if (!ret)
> *value = ret.value;
>
> part.
Damn, and even worse it isn't used at all. I'll probably remove it
entirely and keep the strict minimum for this series.
Thanks,
Clément
>
>> +
>> + return sbi_err_map_linux_errno(ret.error);
>> }
>>
>> /**
>> @@ -321,7 +331,15 @@ int sbi_fwft_get(u32 feature, unsigned long *value)
>> */
>> int sbi_fwft_set(u32 feature, unsigned long value, unsigned long flags)
>> {
>> - return -EOPNOTSUPP;
>> + struct sbiret ret;
>> +
>> + if (!sbi_fwft_supported)
>> + return -EOPNOTSUPP;
>> +
>> + ret = sbi_ecall(SBI_EXT_FWFT, SBI_EXT_FWFT_SET,
>> + feature, value, flags, 0, 0, 0);
>> +
>> + return sbi_err_map_linux_errno(ret.error);
>> }
>>
>> struct fwft_set_req {
>> @@ -360,6 +378,9 @@ int sbi_fwft_local_set_cpumask(const cpumask_t *mask, u32 feature,
>> .error = ATOMIC_INIT(0),
>> };
>>
>> + if (!sbi_fwft_supported)
>> + return -EOPNOTSUPP;
>> +
>> if (feature & SBI_FWFT_GLOBAL_FEATURE_BIT)
>> return -EINVAL;
>>
>> @@ -691,6 +712,11 @@ void __init sbi_init(void)
>> pr_info("SBI DBCN extension detected\n");
>> sbi_debug_console_available = true;
>> }
>> + if ((sbi_spec_version >= sbi_mk_version(3, 0)) &&
>> + (sbi_probe_extension(SBI_EXT_FWFT) > 0)) {
>> + pr_info("SBI FWFT extension detected\n");
>> + sbi_fwft_supported = true;
>> + }
>> } else {
>> __sbi_set_timer = __sbi_set_timer_v01;
>> __sbi_send_ipi = __sbi_send_ipi_v01;
>> --
>> 2.47.2
>>
>
> Thanks,
> drew
