1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * ACRN detection support 4 * 5 * Copyright (C) 2019 Intel Corporation. All rights reserved. 6 * 7 * Jason Chen CJ <jason.cj.chen@intel.com> 8 * Zhao Yakui <yakui.zhao@intel.com> 9 * 10 */ 11 12 #include <linux/interrupt.h> 13 14 #include <asm/acrn.h> 15 #include <asm/apic.h> 16 #include <asm/cpufeatures.h> 17 #include <asm/desc.h> 18 #include <asm/hypervisor.h> 19 #include <asm/idtentry.h> 20 #include <asm/irq_regs.h> 21 22 static u32 __init acrn_detect(void) 23 { 24 return acrn_cpuid_base(); 25 } 26 27 static void __init acrn_init_platform(void) 28 { 29 /* Setup the IDT for ACRN hypervisor callback */ 30 alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_acrn_hv_callback); 31 } 32 33 static bool acrn_x2apic_available(void) 34 { 35 return boot_cpu_has(X86_FEATURE_X2APIC); 36 } 37 38 static void (*acrn_intr_handler)(void); 39 40 DEFINE_IDTENTRY_SYSVEC(sysvec_acrn_hv_callback) 41 { 42 struct pt_regs *old_regs = set_irq_regs(regs); 43 44 /* 45 * The hypervisor requires that the APIC EOI should be acked. 46 * If the APIC EOI is not acked, the APIC ISR bit for the 47 * HYPERVISOR_CALLBACK_VECTOR will not be cleared and then it 48 * will block the interrupt whose vector is lower than 49 * HYPERVISOR_CALLBACK_VECTOR. 50 */ 51 ack_APIC_irq(); 52 inc_irq_stat(irq_hv_callback_count); 53 54 if (acrn_intr_handler) 55 acrn_intr_handler(); 56 57 set_irq_regs(old_regs); 58 } 59 60 void acrn_setup_intr_handler(void (*handler)(void)) 61 { 62 acrn_intr_handler = handler; 63 } 64 EXPORT_SYMBOL_GPL(acrn_setup_intr_handler); 65 66 void acrn_remove_intr_handler(void) 67 { 68 acrn_intr_handler = NULL; 69 } 70 EXPORT_SYMBOL_GPL(acrn_remove_intr_handler); 71 72 const __initconst struct hypervisor_x86 x86_hyper_acrn = { 73 .name = "ACRN", 74 .detect = acrn_detect, 75 .type = X86_HYPER_ACRN, 76 .init.init_platform = acrn_init_platform, 77 .init.x2apic_available = acrn_x2apic_available, 78 }; 79