// SPDX-License-Identifier: GPL-2.0 /* * ACRN detection support * * Copyright (C) 2019 Intel Corporation. All rights reserved. * * Jason Chen CJ <jason.cj.chen@intel.com> * Zhao Yakui <yakui.zhao@intel.com> * */ #include <linux/interrupt.h> #include <asm/apic.h> #include <asm/desc.h> #include <asm/hypervisor.h> #include <asm/idtentry.h> #include <asm/irq_regs.h> static uint32_t __init acrn_detect(void) { return hypervisor_cpuid_base("ACRNACRNACRN\0\0", 0); } static void __init acrn_init_platform(void) { /* Setup the IDT for ACRN hypervisor callback */ alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_acrn_hv_callback); } static bool acrn_x2apic_available(void) { /* * x2apic is not supported for now. Future enablement will have to check * X86_FEATURE_X2APIC to determine whether x2apic is supported in the * guest. */ return false; } static void (*acrn_intr_handler)(void); DEFINE_IDTENTRY_SYSVEC(sysvec_acrn_hv_callback) { struct pt_regs *old_regs = set_irq_regs(regs); /* * The hypervisor requires that the APIC EOI should be acked. * If the APIC EOI is not acked, the APIC ISR bit for the * HYPERVISOR_CALLBACK_VECTOR will not be cleared and then it * will block the interrupt whose vector is lower than * HYPERVISOR_CALLBACK_VECTOR. */ ack_APIC_irq(); inc_irq_stat(irq_hv_callback_count); if (acrn_intr_handler) acrn_intr_handler(); set_irq_regs(old_regs); } const __initconst struct hypervisor_x86 x86_hyper_acrn = { .name = "ACRN", .detect = acrn_detect, .type = X86_HYPER_ACRN, .init.init_platform = acrn_init_platform, .init.x2apic_available = acrn_x2apic_available, };