On 29/01/18 18:39, Lorenzo Pieralisi wrote:
> On Mon, Jan 29, 2018 at 05:45:56PM +0000, Marc Zyngier wrote:
>> Since PSCI 1.0 allows the SMCCC version to be (indirectly) probed,
>> let's do that at boot time, and expose the version of the calling
>> convention as part of the psci_ops structure.
>>
>> Signed-off-by: Marc Zyngier <marc.zyng...@arm.com>
>> ---
>> drivers/firmware/psci.c | 21 +++++++++++++++++++++
>> include/linux/psci.h | 6 ++++++
>> 2 files changed, 27 insertions(+)
>>
>> diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c
>> index e9493da2b111..dd035aaa1c33 100644
>> --- a/drivers/firmware/psci.c
>> +++ b/drivers/firmware/psci.c
>> @@ -511,6 +511,26 @@ static void __init psci_init_migrate(void)
>> pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);
>> }
>>
>> +static void __init psci_init_smccc(u32 ver)
>> +{
>> + int feature = PSCI_RET_NOT_SUPPORTED;
>> +
>> + if (PSCI_VERSION_MAJOR(ver) >= 1)
>> + feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);
>> +
>> + if (feature == PSCI_RET_NOT_SUPPORTED) {
>> + psci_ops.variant = SMCCC_VARIANT_1_0;
>> + } else {
>> + ver = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
>> + if (ver != ARM_SMCCC_VERSION_1_1)
>> + psci_ops.variant = SMCCC_VARIANT_1_0;
>> + else
>> + psci_ops.variant = SMCCC_VARIANT_1_1;
>> + }
>> +
>> + pr_info("SMC Calling Convention v1.%d\n", psci_ops.variant);
>> +}
>> +
>> static void __init psci_0_2_set_functions(void)
>> {
>> pr_info("Using standard PSCI v0.2 function IDs\n");
>> @@ -557,6 +577,7 @@ static int __init psci_probe(void)
>> psci_0_2_set_functions();
>>
>> psci_init_migrate();
>> + psci_init_smccc(ver);
>
> Given that SMCCC_VARIANT_1_0 is already the default value (unless you do
> the same we did with the conduit) we can move psci_init_smccc() call
> inside the if below (that is there to detect a callable psci_features())
> and remove the check in psci_init_smccc(), up to you.
Yes, this makes sense.
>
>>
>> if (PSCI_VERSION_MAJOR(ver) >= 1) {
>> psci_init_cpu_suspend();
>> diff --git a/include/linux/psci.h b/include/linux/psci.h
>> index f2679e5faa4f..83fd16a37be3 100644
>> --- a/include/linux/psci.h
>> +++ b/include/linux/psci.h
>> @@ -31,6 +31,11 @@ enum psci_conduit {
>> PSCI_CONDUIT_HVC,
>> };
>>
>> +enum smccc_variant {
>> + SMCCC_VARIANT_1_0,
>> + SMCCC_VARIANT_1_1,
>> +};
>> +
>> struct psci_operations {
>> u32 (*get_version)(void);
>> int (*cpu_suspend)(u32 state, unsigned long entry_point);
>> @@ -41,6 +46,7 @@ struct psci_operations {
>> unsigned long lowest_affinity_level);
>> int (*migrate_info_type)(void);
>> enum psci_conduit conduit;
>> + enum smccc_variant variant;
>
> Nit: I would add an smccc_ prefix to the variant field (or rename it
> to smccc_version).
I've renamed both the field and the enum to smccc_version (as well as
the members of the enum). This is definitely more consistent with the
symbols exposed by arm-smccc.h.
>
> You can add my:
>
> Acked-by: Lorenzo Pieralisi <lorenzo.pieral...@arm.com>
>
Thanks,
M.
--
Jazz is not dead. It just smells funny...
