4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Mark Rutland <[email protected]> From: Marc Zyngier <[email protected]> commit e78eef554a912ef6c1e0bbf97619dafbeae3339f upstream. 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. Acked-by: Lorenzo Pieralisi <[email protected]> Reviewed-by: Robin Murphy <[email protected]> Tested-by: Ard Biesheuvel <[email protected]> Signed-off-by: Marc Zyngier <[email protected]> Signed-off-by: Catalin Marinas <[email protected]> Signed-off-by: Mark Rutland <[email protected]> [v4.9 backport] Tested-by: Greg Hackmann <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/firmware/psci.c | 27 +++++++++++++++++++++++++++ include/linux/psci.h | 6 ++++++ 2 files changed, 33 insertions(+) --- a/drivers/firmware/psci.c +++ b/drivers/firmware/psci.c @@ -61,6 +61,7 @@ bool psci_tos_resident_on(int cpu) struct psci_operations psci_ops = { .conduit = PSCI_CONDUIT_NONE, + .smccc_version = SMCCC_VERSION_1_0, }; typedef unsigned long (psci_fn)(unsigned long, unsigned long, @@ -511,6 +512,31 @@ static void __init psci_init_migrate(voi pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid); } +static void __init psci_init_smccc(void) +{ + u32 ver = ARM_SMCCC_VERSION_1_0; + int feature; + + feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID); + + if (feature != PSCI_RET_NOT_SUPPORTED) { + u32 ret; + ret = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0); + if (ret == ARM_SMCCC_VERSION_1_1) { + psci_ops.smccc_version = SMCCC_VERSION_1_1; + ver = ret; + } + } + + /* + * Conveniently, the SMCCC and PSCI versions are encoded the + * same way. No, this isn't accidental. + */ + pr_info("SMC Calling Convention v%d.%d\n", + PSCI_VERSION_MAJOR(ver), PSCI_VERSION_MINOR(ver)); + +} + static void __init psci_0_2_set_functions(void) { pr_info("Using standard PSCI v0.2 function IDs\n"); @@ -559,6 +585,7 @@ static int __init psci_probe(void) psci_init_migrate(); if (PSCI_VERSION_MAJOR(ver) >= 1) { + psci_init_smccc(); psci_init_cpu_suspend(); psci_init_system_suspend(); } --- a/include/linux/psci.h +++ b/include/linux/psci.h @@ -31,6 +31,11 @@ enum psci_conduit { PSCI_CONDUIT_HVC, }; +enum smccc_version { + SMCCC_VERSION_1_0, + SMCCC_VERSION_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_version smccc_version; }; extern struct psci_operations psci_ops;

