diff --git a/arch/arm64/kvm/hyp/nvhe/ffa.c b/arch/arm64/kvm/hyp/nvhe/ffa.c index 02746f9d0980f..c8ab51c331f00 100644 --- a/arch/arm64/kvm/hyp/nvhe/ffa.c +++ b/arch/arm64/kvm/hyp/nvhe/ffa.c @@ -67,6 +67,9 @@ struct kvm_ffa_buffers { */ static struct kvm_ffa_buffers hyp_buffers; static struct kvm_ffa_buffers host_buffers; +static u32 hyp_ffa_version; +static bool has_version_negotiated; +static hyp_spinlock_t version_lock; static void ffa_to_smccc_error(struct arm_smccc_res *res, u64 ffa_errno) { @@ -639,6 +642,83 @@ static bool do_ffa_features(struct arm_smccc_res *res, return true; } +static int hyp_ffa_post_init(void) +{ + size_t min_rxtx_sz; + struct arm_smccc_res res; + + arm_smccc_1_1_smc(FFA_ID_GET, 0, 0, 0, 0, 0, 0, 0, &res); + if (res.a0 != FFA_SUCCESS) + return -EOPNOTSUPP; + + if (res.a2 != HOST_FFA_ID) + return -EINVAL; + + arm_smccc_1_1_smc(FFA_FEATURES, FFA_FN64_RXTX_MAP, + 0, 0, 0, 0, 0, 0, &res); + if (res.a0 != FFA_SUCCESS) + return -EOPNOTSUPP; + + switch (res.a2) { + case FFA_FEAT_RXTX_MIN_SZ_4K: + min_rxtx_sz = SZ_4K; + break; + case FFA_FEAT_RXTX_MIN_SZ_16K: + min_rxtx_sz = SZ_16K; + break; + case FFA_FEAT_RXTX_MIN_SZ_64K: + min_rxtx_sz = SZ_64K; + break; + default: + return -EINVAL; + } + + if (min_rxtx_sz > PAGE_SIZE) + return -EOPNOTSUPP; + + return 0; +} + +static void do_ffa_version(struct arm_smccc_res *res, + struct kvm_cpu_context *ctxt) +{ + DECLARE_REG(u32, ffa_req_version, ctxt, 1); + + if (FFA_MAJOR_VERSION(ffa_req_version) != 1) { + res->a0 = FFA_RET_NOT_SUPPORTED; + return; + } + + hyp_spin_lock(&version_lock); + if (has_version_negotiated) { + res->a0 = hyp_ffa_version; + goto unlock; + } + + /* + * If the client driver tries to downgrade the version, we need to ask + * first if TEE supports it. + */ + if (FFA_MINOR_VERSION(ffa_req_version) < FFA_MINOR_VERSION(hyp_ffa_version)) { + arm_smccc_1_1_smc(FFA_VERSION, ffa_req_version, 0, + 0, 0, 0, 0, 0, + res); + if (res->a0 == FFA_RET_NOT_SUPPORTED) + goto unlock; + + hyp_ffa_version = ffa_req_version; + } + + if (hyp_ffa_post_init()) + res->a0 = FFA_RET_NOT_SUPPORTED; + else { + has_version_negotiated = true; + res->a0 = hyp_ffa_version; + } +unlock: + hyp_spin_unlock(&version_lock); +} + bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id) { struct arm_smccc_res res; @@ -659,6 +739,11 @@ bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id) if (!is_ffa_call(func_id)) return false; + if (!has_version_negotiated && func_id != FFA_VERSION) { + ffa_to_smccc_error(&res, FFA_RET_INVALID_PARAMETERS); + goto out_handled; + } + switch (func_id) { case FFA_FEATURES: if (!do_ffa_features(&res, host_ctxt)) @@ -685,6 +770,9 @@ bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id) case FFA_MEM_FRAG_TX: do_ffa_mem_frag_tx(&res, host_ctxt); goto out_handled; + case FFA_VERSION: + do_ffa_version(&res, host_ctxt); + goto out_handled; } if (ffa_call_supported(func_id)) @@ -699,7 +787,6 @@ bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id) int hyp_ffa_init(void *pages) { struct arm_smccc_res res; - size_t min_rxtx_sz; void *tx, *rx; if (kvm_host_psci_config.smccc_version < ARM_SMCCC_VERSION_1_2) @@ -725,35 +812,7 @@ int hyp_ffa_init(void *pages) if (FFA_MAJOR_VERSION(res.a0) != 1) return -EOPNOTSUPP; - arm_smccc_1_1_smc(FFA_ID_GET, 0, 0, 0, 0, 0, 0, 0, &res); - if (res.a0 != FFA_SUCCESS) - return -EOPNOTSUPP; - - if (res.a2 != HOST_FFA_ID) - return -EINVAL; - - arm_smccc_1_1_smc(FFA_FEATURES, FFA_FN64_RXTX_MAP, - 0, 0, 0, 0, 0, 0, &res); - if (res.a0 != FFA_SUCCESS) - return -EOPNOTSUPP; - - switch (res.a2) { - case FFA_FEAT_RXTX_MIN_SZ_4K: - min_rxtx_sz = SZ_4K; - break; - case FFA_FEAT_RXTX_MIN_SZ_16K: - min_rxtx_sz = SZ_16K; - break; - case FFA_FEAT_RXTX_MIN_SZ_64K: - min_rxtx_sz = SZ_64K; - break; - default: - return -EINVAL; - } - - if (min_rxtx_sz > PAGE_SIZE) - return -EOPNOTSUPP; - + hyp_ffa_version = FFA_VERSION_1_0; tx = pages; pages += KVM_FFA_MBOX_NR_PAGES * PAGE_SIZE; rx = pages; @@ -775,5 +834,6 @@ int hyp_ffa_init(void *pages) .lock = __HYP_SPIN_LOCK_UNLOCKED, }; + version_lock = __HYP_SPIN_LOCK_UNLOCKED; return 0; }