| 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, addr: asm_sysvec_acrn_hv_callback); |
| 31 | |
| 32 | x86_platform.calibrate_tsc = acrn_get_tsc_khz; |
| 33 | x86_platform.calibrate_cpu = acrn_get_tsc_khz; |
| 34 | } |
| 35 | |
| 36 | static bool acrn_x2apic_available(void) |
| 37 | { |
| 38 | return boot_cpu_has(X86_FEATURE_X2APIC); |
| 39 | } |
| 40 | |
| 41 | static void (*acrn_intr_handler)(void); |
| 42 | |
| 43 | DEFINE_IDTENTRY_SYSVEC(sysvec_acrn_hv_callback) |
| 44 | { |
| 45 | struct pt_regs *old_regs = set_irq_regs(regs); |
| 46 | |
| 47 | /* |
| 48 | * The hypervisor requires that the APIC EOI should be acked. |
| 49 | * If the APIC EOI is not acked, the APIC ISR bit for the |
| 50 | * HYPERVISOR_CALLBACK_VECTOR will not be cleared and then it |
| 51 | * will block the interrupt whose vector is lower than |
| 52 | * HYPERVISOR_CALLBACK_VECTOR. |
| 53 | */ |
| 54 | apic_eoi(); |
| 55 | inc_irq_stat(irq_hv_callback_count); |
| 56 | |
| 57 | if (acrn_intr_handler) |
| 58 | acrn_intr_handler(); |
| 59 | |
| 60 | set_irq_regs(old_regs); |
| 61 | } |
| 62 | |
| 63 | void acrn_setup_intr_handler(void (*handler)(void)) |
| 64 | { |
| 65 | acrn_intr_handler = handler; |
| 66 | } |
| 67 | EXPORT_SYMBOL_GPL(acrn_setup_intr_handler); |
| 68 | |
| 69 | void acrn_remove_intr_handler(void) |
| 70 | { |
| 71 | acrn_intr_handler = NULL; |
| 72 | } |
| 73 | EXPORT_SYMBOL_GPL(acrn_remove_intr_handler); |
| 74 | |
| 75 | const __initconst struct hypervisor_x86 x86_hyper_acrn = { |
| 76 | .name = "ACRN", |
| 77 | .detect = acrn_detect, |
| 78 | .type = X86_HYPER_ACRN, |
| 79 | .init.init_platform = acrn_init_platform, |
| 80 | .init.x2apic_available = acrn_x2apic_available, |
| 81 | }; |
| 82 |