From 883a91d37ff3809d3c5a144ec0a59f4f68509acc Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Thu, 12 Apr 2018 12:11:34 +0100 Subject: [PATCH] firmware/psci: Expose SMCCC version through psci_ops From: Marc Zyngier 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 Reviewed-by: Robin Murphy Tested-by: Ard Biesheuvel Signed-off-by: Marc Zyngier Signed-off-by: Catalin Marinas Signed-off-by: Mark Rutland [v4.9 backport] Tested-by: Greg Hackmann Signed-off-by: Greg Kroah-Hartman --- drivers/firmware/psci.c | 27 +++++++++++++++++++++++++++ include/linux/psci.h | 6 ++++++ 2 files changed, 33 insertions(+) diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c index a49196ae0840..79a48c37fb35 100644 --- 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(void) 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(); } diff --git a/include/linux/psci.h b/include/linux/psci.h index 66ff54787d3e..347077cf19c6 100644 --- 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; -- 2.20.1