1 // SPDX-License-Identifier: GPL-2.0 2 3 #define pr_fmt(fmt) "smccc: KVM: " fmt 4 5 #include <linux/arm-smccc.h> 6 #include <linux/bitmap.h> 7 #include <linux/kernel.h> 8 #include <linux/string.h> 9 10 #include <asm/hypervisor.h> 11 12 static DECLARE_BITMAP(__kvm_arm_hyp_services, ARM_SMCCC_KVM_NUM_FUNCS) __ro_after_init = { }; 13 14 void __init kvm_init_hyp_services(void) 15 { 16 struct arm_smccc_res res; 17 u32 val[4]; 18 19 if (arm_smccc_1_1_get_conduit() != SMCCC_CONDUIT_HVC) 20 return; 21 22 arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID, &res); 23 if (res.a0 != ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_0 || 24 res.a1 != ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_1 || 25 res.a2 != ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_2 || 26 res.a3 != ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_3) 27 return; 28 29 memset(&res, 0, sizeof(res)); 30 arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID, &res); 31 32 val[0] = lower_32_bits(res.a0); 33 val[1] = lower_32_bits(res.a1); 34 val[2] = lower_32_bits(res.a2); 35 val[3] = lower_32_bits(res.a3); 36 37 bitmap_from_arr32(__kvm_arm_hyp_services, val, ARM_SMCCC_KVM_NUM_FUNCS); 38 39 pr_info("hypervisor services detected (0x%08lx 0x%08lx 0x%08lx 0x%08lx)\n", 40 res.a3, res.a2, res.a1, res.a0); 41 } 42 43 bool kvm_arm_hyp_service_available(u32 func_id) 44 { 45 if (func_id >= ARM_SMCCC_KVM_NUM_FUNCS) 46 return false; 47 48 return test_bit(func_id, __kvm_arm_hyp_services); 49 } 50 EXPORT_SYMBOL_GPL(kvm_arm_hyp_service_available); 51