From: Marc Zyngier marc.zyngier@arm.com
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 lorenzo.pieralisi@arm.com Reviewed-by: Robin Murphy robin.murphy@arm.com Tested-by: Ard Biesheuvel ard.biesheuvel@linaro.org Signed-off-by: Marc Zyngier marc.zyngier@arm.com Signed-off-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Mark Rutland mark.rutland@arm.com [v4.9 backport] Tested-by: Greg Hackmann ghackmann@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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 @@ -57,6 +57,7 @@ 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, @@ -339,6 +340,31 @@ 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"); @@ -385,6 +411,7 @@ 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 @@ -30,6 +30,11 @@ enum psci_conduit { PSCI_CONDUIT_HVC, };
+enum smccc_version { + SMCCC_VERSION_1_0, + SMCCC_VERSION_1_1, +}; + struct psci_operations { int (*cpu_suspend)(u32 state, unsigned long entry_point); int (*cpu_off)(u32 state); @@ -39,6 +44,7 @@ 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;