88 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			88 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
 | |
| 
 | |
| /*
 | |
|  * Core routines for interacting with Microsoft's Hyper-V hypervisor,
 | |
|  * including hypervisor initialization.
 | |
|  *
 | |
|  * Copyright (C) 2021, Microsoft, Inc.
 | |
|  *
 | |
|  * Author : Michael Kelley <mikelley@microsoft.com>
 | |
|  */
 | |
| 
 | |
| #include <linux/types.h>
 | |
| #include <linux/acpi.h>
 | |
| #include <linux/export.h>
 | |
| #include <linux/errno.h>
 | |
| #include <linux/version.h>
 | |
| #include <linux/cpuhotplug.h>
 | |
| #include <asm/mshyperv.h>
 | |
| 
 | |
| static bool hyperv_initialized;
 | |
| 
 | |
| int hv_get_hypervisor_version(union hv_hypervisor_version_info *info)
 | |
| {
 | |
| 	hv_get_vpreg_128(HV_REGISTER_HYPERVISOR_VERSION,
 | |
| 			 (struct hv_get_vp_registers_output *)info);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int __init hyperv_init(void)
 | |
| {
 | |
| 	struct hv_get_vp_registers_output	result;
 | |
| 	u64	guest_id;
 | |
| 	int	ret;
 | |
| 
 | |
| 	/*
 | |
| 	 * Allow for a kernel built with CONFIG_HYPERV to be running in
 | |
| 	 * a non-Hyper-V environment, including on DT instead of ACPI.
 | |
| 	 * In such cases, do nothing and return success.
 | |
| 	 */
 | |
| 	if (acpi_disabled)
 | |
| 		return 0;
 | |
| 
 | |
| 	if (strncmp((char *)&acpi_gbl_FADT.hypervisor_id, "MsHyperV", 8))
 | |
| 		return 0;
 | |
| 
 | |
| 	/* Setup the guest ID */
 | |
| 	guest_id = hv_generate_guest_id(LINUX_VERSION_CODE);
 | |
| 	hv_set_vpreg(HV_REGISTER_GUEST_OS_ID, guest_id);
 | |
| 
 | |
| 	/* Get the features and hints from Hyper-V */
 | |
| 	hv_get_vpreg_128(HV_REGISTER_FEATURES, &result);
 | |
| 	ms_hyperv.features = result.as32.a;
 | |
| 	ms_hyperv.priv_high = result.as32.b;
 | |
| 	ms_hyperv.misc_features = result.as32.c;
 | |
| 
 | |
| 	hv_get_vpreg_128(HV_REGISTER_ENLIGHTENMENTS, &result);
 | |
| 	ms_hyperv.hints = result.as32.a;
 | |
| 
 | |
| 	pr_info("Hyper-V: privilege flags low 0x%x, high 0x%x, hints 0x%x, misc 0x%x\n",
 | |
| 		ms_hyperv.features, ms_hyperv.priv_high, ms_hyperv.hints,
 | |
| 		ms_hyperv.misc_features);
 | |
| 
 | |
| 	ret = hv_common_init();
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	ret = cpuhp_setup_state(CPUHP_AP_HYPERV_ONLINE, "arm64/hyperv_init:online",
 | |
| 				hv_common_cpu_init, hv_common_cpu_die);
 | |
| 	if (ret < 0) {
 | |
| 		hv_common_free();
 | |
| 		return ret;
 | |
| 	}
 | |
| 
 | |
| 	ms_hyperv_late_init();
 | |
| 
 | |
| 	hyperv_initialized = true;
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| early_initcall(hyperv_init);
 | |
| 
 | |
| bool hv_is_hyperv_initialized(void)
 | |
| {
 | |
| 	return hyperv_initialized;
 | |
| }
 | |
| EXPORT_SYMBOL_GPL(hv_is_hyperv_initialized);
 |