Re: git: 6cf00ef80c20 - main - arm64: enablement for ARM64 in Hyper-V (Part 1)

From: Andrew Turner <andrew_at_fubar.geek.nz>
Date: Thu, 29 Sep 2022 14:12:58 UTC
It looks like you have the contents of sys/dev/hyperv/vmbus/aarch64/hyperv_aarch64.c duplicated.

Andrew

> On 29 Sep 2022, at 11:19, Wei Hu <whu@FreeBSD.org> wrote:
> 
> The branch main has been updated by whu:
> 
> URL: https://cgit.FreeBSD.org/src/commit/?id=6cf00ef80c2014811bb6ce35e969b95dfe574793
> 
> commit 6cf00ef80c2014811bb6ce35e969b95dfe574793
> Author:     Souradeep Chakrabarti <schakrabarti@microsoft.com>
> AuthorDate: 2022-09-29 09:57:46 +0000
> Commit:     Wei Hu <whu@FreeBSD.org>
> CommitDate: 2022-09-29 10:14:41 +0000
> 
>    arm64: enablement for ARM64 in Hyper-V (Part 1)
> 
>    The changes are to refactor the code of vmbus.c and hyperv.c to keep minimal
>    arch specific codes there and have them in separate files in x86/ arm64/ .
>    x86 is a new directory, which contains codes for x86 / x86_64. Instead of
>    repeating the same codes in existing amd64/ and i386/, this approach reduced
>    the repetition. This is first of three patches for Hyper-V enablement.
> 
>    Reviewed by:    whu
>    Tested by:      Souradeep Chakrabarti <schakrabarti@microsoft.com>
>    Sponsored by:   Microsoft
>    Differential Revision:  https://reviews.freebsd.org/D36466
> ---
> sys/dev/hyperv/vmbus/aarch64/hyperv_aarch64.c | 190 +++++++++++++
> sys/dev/hyperv/vmbus/aarch64/hyperv_machdep.c | 103 +++++++
> sys/dev/hyperv/vmbus/aarch64/hyperv_machdep.h |  59 ++++
> sys/dev/hyperv/vmbus/aarch64/hyperv_reg.h     | 386 ++++++++++++++++++++++++++
> sys/dev/hyperv/vmbus/aarch64/vmbus_aarch64.c  | 314 +++++++++++++++++++++
> 5 files changed, 1052 insertions(+)
> 
> diff --git a/sys/dev/hyperv/vmbus/aarch64/hyperv_aarch64.c b/sys/dev/hyperv/vmbus/aarch64/hyperv_aarch64.c
> new file mode 100644
> index 000000000000..6104e88130db
> --- /dev/null
> +++ b/sys/dev/hyperv/vmbus/aarch64/hyperv_aarch64.c
> @@ -0,0 +1,190 @@
> +/*- SPDX-License-Identifier: BSD-2-Clause-FreeBSD
> + * Copyright (c) 2009-2012,2016-2017, 2022 Microsoft Corp.
> + * Copyright (c) 2012 NetApp Inc.
> + * Copyright (c) 2012 Citrix Inc.
> + * All rights reserved.
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions
> + * are met:
> + * 1. Redistributions of source code must retain the above copyright
> + *    notice unmodified, this list of conditions, and the following
> + *    disclaimer.
> + * 2. Redistributions in binary form must reproduce the above copyright
> + *    notice, this list of conditions and the following disclaimer in the
> + *    documentation and/or other materials provided with the distribution.
> + *
> + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
> + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
> + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
> + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
> + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
> + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + */
> +
> +/**
> + * Implements low-level interactions with Hyper-V/Azure
> + */
> +
> +#include <sys/cdefs.h>
> +__FBSDID("$FreeBSD$");
> +
> +#include <sys/param.h>
> +#include <sys/systm.h>
> +#include <sys/kernel.h>
> +#include <sys/malloc.h>
> +#include <sys/timetc.h>
> +
> +#include <vm/vm.h>
> +#include <vm/pmap.h>
> +#include <vm/vm_extern.h>
> +#include <vm/vm_kern.h>
> +
> +#include <dev/hyperv/include/hyperv.h>
> +#include <dev/hyperv/include/hyperv_busdma.h>
> +#include <dev/hyperv/vmbus/aarch64/hyperv_machdep.h>
> +#include <dev/hyperv/vmbus/aarch64/hyperv_reg.h>
> +#include <dev/hyperv/vmbus/hyperv_var.h>
> +
> +void hyperv_init_tc(void);
> +int hypercall_page_setup(vm_paddr_t);
> +void hypercall_disable(void);
> +bool hyperv_identify_features(void);
> +
> +u_int hyperv_ver_major;
> +u_int hyperv_features;
> +u_int hyperv_recommends;
> +
> +hyperv_tc64_t hyperv_tc64;
> +
> +void
> +hyperv_init_tc(void)
> +{
> +	hyperv_tc64 = NULL;
> +}
> +
> +int
> +hypercall_page_setup(vm_paddr_t hc)
> +{
> +	return (0);
> +}
> +
> +void
> +hypercall_disable(void)
> +{
> +	return;
> +}
> +
> +bool
> +hyperv_identify_features(void)
> +{
> +	struct hv_get_vp_registers_output result;
> +	vm_guest = VM_GUEST_HV;
> +
> +	hv_get_vpreg_128(CPUID_LEAF_HV_FEATURES, &result);
> +	hyperv_features = result.as32.a;
> +	hv_get_vpreg_128(CPUID_LEAF_HV_IDENTITY, &result);
> +	hyperv_ver_major = result.as32.b >> 16;
> +	hv_get_vpreg_128(CPUID_LEAF_HV_RECOMMENDS, &result);
> +	hyperv_recommends = result.as32.a;
> +	return (true);
> +}
> +/*- SPDX-License-Identifier: BSD-2-Clause-FreeBSD
> + * Copyright (c) 2009-2012,2016-2017, 2022 Microsoft Corp.
> + * Copyright (c) 2012 NetApp Inc.
> + * Copyright (c) 2012 Citrix Inc.
> + * All rights reserved.
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions
> + * are met:
> + * 1. Redistributions of source code must retain the above copyright
> + *    notice unmodified, this list of conditions, and the following
> + *    disclaimer.
> + * 2. Redistributions in binary form must reproduce the above copyright
> + *    notice, this list of conditions and the following disclaimer in the
> + *    documentation and/or other materials provided with the distribution.
> + *
> + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
> + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
> + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
> + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
> + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
> + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + */
> +
> +/**
> + * Implements low-level interactions with Hyper-V/Azure
> + */
> +
> +#include <sys/cdefs.h>
> +__FBSDID("$FreeBSD$");
> +
> +#include <sys/param.h>
> +#include <sys/systm.h>
> +#include <sys/kernel.h>
> +#include <sys/malloc.h>
> +#include <sys/timetc.h>
> +
> +#include <vm/vm.h>
> +#include <vm/pmap.h>
> +#include <vm/vm_extern.h>
> +#include <vm/vm_kern.h>
> +
> +#include <dev/hyperv/include/hyperv.h>
> +#include <dev/hyperv/include/hyperv_busdma.h>
> +#include <dev/hyperv/vmbus/aarch64/hyperv_machdep.h>
> +#include <dev/hyperv/vmbus/aarch64/hyperv_reg.h>
> +#include <dev/hyperv/vmbus/hyperv_var.h>
> +
> +void hyperv_init_tc(void);
> +int hypercall_page_setup(vm_paddr_t);
> +void hypercall_disable(void);
> +bool hyperv_identify_features(void);
> +
> +u_int hyperv_ver_major;
> +u_int hyperv_features;
> +u_int hyperv_recommends;
> +
> +hyperv_tc64_t hyperv_tc64;
> +
> +void
> +hyperv_init_tc(void)
> +{
> +	hyperv_tc64 = NULL;
> +}
> +
> +int
> +hypercall_page_setup(vm_paddr_t hc)
> +{
> +	return (0);
> +}
> +
> +void
> +hypercall_disable(void)
> +{
> +	return;
> +}
> +
> +bool
> +hyperv_identify_features(void)
> +{
> +	struct hv_get_vp_registers_output result;
> +	vm_guest = VM_GUEST_HV;
> +
> +	hv_get_vpreg_128(CPUID_LEAF_HV_FEATURES, &result);
> +	hyperv_features = result.as32.a;
> +	hv_get_vpreg_128(CPUID_LEAF_HV_IDENTITY, &result);
> +	hyperv_ver_major = result.as32.b >> 16;
> +	hv_get_vpreg_128(CPUID_LEAF_HV_RECOMMENDS, &result);
> +	hyperv_recommends = result.as32.a;
> +	return (true);
> +}
> diff --git a/sys/dev/hyperv/vmbus/aarch64/hyperv_machdep.c b/sys/dev/hyperv/vmbus/aarch64/hyperv_machdep.c
> new file mode 100644
> index 000000000000..9bfe34044335
> --- /dev/null
> +++ b/sys/dev/hyperv/vmbus/aarch64/hyperv_machdep.c
> @@ -0,0 +1,103 @@
> +/*- SPDX-License-Identifier: BSD-2-Clause-FreeBSD
> + *
> + * Copyright (c) 2016-2017,2022 Microsoft Corp.
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions
> + * are met:
> + * 1. Redistributions of source code must retain the above copyright
> + *    notice unmodified, this list of conditions, and the following
> + *    disclaimer.
> + * 2. Redistributions in binary form must reproduce the above copyright
> + *    notice, this list of conditions and the following disclaimer in the
> + *    documentation and/or other materials provided with the distribution.
> + *
> + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
> + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
> + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
> + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
> + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
> + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + */
> +
> +#include <sys/cdefs.h>
> +__FBSDID("$FreeBSD$");
> +
> +#include <dev/hyperv/include/hyperv.h>
> +#include <dev/hyperv/include/hyperv_busdma.h>
> +#include <dev/hyperv/vmbus/aarch64/hyperv_machdep.h>
> +#include <dev/hyperv/vmbus/aarch64/hyperv_reg.h>
> +#include <dev/hyperv/vmbus/hyperv_var.h>
> +#include <dev/psci/smccc.h>
> +
> +#define HVCALL_SET_VP_REGISTERS 0x0051
> +#define HVCALL_GET_VP_REGISTERS 0x0050
> +#define BIT(A) (1 << (A))
> +#define HV_HYPERCALL_FAST_BIT BIT(16)
> +#define BIT_ULL(a) (1ULL << (a))
> +#define HV_HYPERCALL_REP_COMP_1 BIT_ULL(32)
> +#define HV_PARTITION_ID_SELF ((u64)-1)
> +#define HV_VP_INDEX_SELF ((u32)-2)
> +#define HV_SMCCC_FUNC_NUMBER 1
> +
> +#define HV_FUNC_ID                                           \
> +	SMCCC_FUNC_ID(SMCCC_YIELDING_CALL, SMCCC_64BIT_CALL, \
> +	    SMCCC_VENDOR_HYP_SERVICE_CALLS, HV_SMCCC_FUNC_NUMBER)
> +
> +void
> +arm_hv_set_vreg(u32 msr, u64 value)
> +{
> +	arm_smccc_hvc(HV_FUNC_ID,
> +	    HVCALL_SET_VP_REGISTERS | HV_HYPERCALL_FAST_BIT |
> +		HV_HYPERCALL_REP_COMP_1,
> +	    HV_PARTITION_ID_SELF, HV_VP_INDEX_SELF, msr, 0, value, 0, NULL);
> +}
> +
> +void
> +hv_get_vpreg_128(u32 msr, struct hv_get_vp_registers_output *result)
> +{
> +	struct arm_smccc_1_2_regs args;
> +	struct arm_smccc_1_2_regs res;
> +
> +	args.a0 = HV_FUNC_ID;
> +	args.a1 = HVCALL_GET_VP_REGISTERS | HV_HYPERCALL_FAST_BIT |
> +	    HV_HYPERCALL_REP_COMP_1;
> +	args.a2 = HV_PARTITION_ID_SELF;
> +	args.a3 = HV_VP_INDEX_SELF;
> +	args.a4 = msr;
> +
> +	/*
> +	 * Use the SMCCC 1.2 interface because the results are in registers
> +	 * beyond X0-X3.
> +	 */
> +	arm_smccc_1_2_hvc(&args, &res);
> +
> +	result->as64.low = res.a6;
> +	result->as64.high = res.a7;
> +}
> +
> +u64
> +arm_hv_get_vreg(u32 msr)
> +{
> +	struct hv_get_vp_registers_output output;
> +
> +	hv_get_vpreg_128(msr, &output);
> +
> +	return (output.as64.low);
> +}
> +
> +uint64_t
> +hypercall_md(volatile void *hc_addr, uint64_t in_val, uint64_t in_paddr,
> +    uint64_t out_paddr)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_hvc(HV_FUNC_ID, in_val, in_paddr, out_paddr, 0, 0, 0, 0,
> +	    &res);
> +
> +	return (res.a0);
> +}
> diff --git a/sys/dev/hyperv/vmbus/aarch64/hyperv_machdep.h b/sys/dev/hyperv/vmbus/aarch64/hyperv_machdep.h
> new file mode 100644
> index 000000000000..b017fdbc14c9
> --- /dev/null
> +++ b/sys/dev/hyperv/vmbus/aarch64/hyperv_machdep.h
> @@ -0,0 +1,59 @@
> +/*- SPDX-License-Identifier: BSD-2-Clause-FreeBSD
> + *
> + * Copyright (c) 2022 Microsoft Corp.
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions
> + * are met:
> + * 1. Redistributions of source code must retain the above copyright
> + *    notice unmodified, this list of conditions, and the following
> + *    disclaimer.
> + * 2. Redistributions in binary form must reproduce the above copyright
> + *    notice, this list of conditions and the following disclaimer in the
> + *    documentation and/or other materials provided with the distribution.
> + *
> + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
> + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
> + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
> + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
> + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
> + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + *
> + * $FreeBSD$
> + */
> +
> +#ifndef _HYPERV_MACHDEP_H_
> +#define _HYPERV_MACHDEP_H_
> +
> +#include <sys/param.h>
> +
> +typedef uint32_t u32;
> +typedef uint64_t u64;
> +struct hv_get_vp_registers_output {
> +	union {
> +		struct {
> +			u32 a;
> +			u32 b;
> +			u32 c;
> +			u32 d;
> +		} as32 __packed;
> +		struct {
> +			u64 low;
> +			u64 high;
> +		} as64 __packed;
> +	};
> +};
> +
> +uint64_t hypercall_md(volatile void *hc_addr, u64 in_val,
> +    u64 in_paddr, u64 out_paddr);
> +void hv_get_vpreg_128(u32, struct hv_get_vp_registers_output *);
> +void arm_hv_set_vreg(u32 msr, u64 val);
> +#define WRMSR(msr, val) arm_hv_set_vreg(msr, val)
> +u64 arm_hv_get_vreg(u32 msr);
> +#define RDMSR(msr) arm_hv_get_vreg(msr)
> +
> +#endif /* !_HYPERV_MACHDEP_H_ */
> diff --git a/sys/dev/hyperv/vmbus/aarch64/hyperv_reg.h b/sys/dev/hyperv/vmbus/aarch64/hyperv_reg.h
> new file mode 100644
> index 000000000000..132b40768790
> --- /dev/null
> +++ b/sys/dev/hyperv/vmbus/aarch64/hyperv_reg.h
> @@ -0,0 +1,386 @@
> +/*- SPDX-License-Identifier: BSD-2-Clause-FreeBSD
> + * Copyright (c) 2022 Microsoft Corp.
> + * All rights reserved.
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions
> + * are met:
> + * 1. Redistributions of source code must retain the above copyright
> + *    notice unmodified, this list of conditions, and the following
> + *    disclaimer.
> + * 2. Redistributions in binary form must reproduce the above copyright
> + *    notice, this list of conditions and the following disclaimer in the
> + *    documentation and/or other materials provided with the distribution.
> + *
> + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
> + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
> + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
> + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
> + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
> + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + *
> + * $FreeBSD$
> + */
> +
> +#ifndef _HYPERV_REG_H_
> +#define _HYPERV_REG_H_
> +
> +#include <sys/param.h>
> +#include <sys/systm.h>
> +
> +/*
> + * Hyper-V Synthetic MSRs
> + */
> +
> +#define MSR_HV_GUEST_OS_ID		0x00090002
> +#define MSR_HV_GUESTID_BUILD_MASK	0xffffULL
> +#define MSR_HV_GUESTID_VERSION_MASK	0x0000ffffffff0000ULL
> +#define MSR_HV_GUESTID_VERSION_SHIFT	16
> +#define MSR_HV_GUESTID_OSID_MASK	0x00ff000000000000ULL
> +#define MSR_HV_GUESTID_OSID_SHIFT	48
> +#define MSR_HV_GUESTID_OSTYPE_MASK	0x7f00000000000000ULL
> +#define MSR_HV_GUESTID_OSTYPE_SHIFT	56
> +#define MSR_HV_GUESTID_OPENSRC		0x8000000000000000ULL
> +#define MSR_HV_GUESTID_OSTYPE_LINUX	\
> +	((0x01ULL << MSR_HV_GUESTID_OSTYPE_SHIFT) | MSR_HV_GUESTID_OPENSRC)
> +#define MSR_HV_GUESTID_OSTYPE_FREEBSD	\
> +	((0x02ULL << MSR_HV_GUESTID_OSTYPE_SHIFT) | MSR_HV_GUESTID_OPENSRC)
> +
> +#define MSR_HV_HYPERCALL		0x40000001
> +#define MSR_HV_HYPERCALL_ENABLE		0x0001ULL
> +#define MSR_HV_HYPERCALL_RSVD_MASK	0x0ffeULL
> +#define MSR_HV_HYPERCALL_PGSHIFT	12
> +
> +#define MSR_HV_VP_INDEX			0x00090003
> +
> +#define MSR_HV_REFERENCE_TSC		0x40000021
> +#define MSR_HV_REFTSC_ENABLE		0x0001ULL
> +#define MSR_HV_REFTSC_RSVD_MASK		0x0ffeULL
> +#define MSR_HV_REFTSC_PGSHIFT		12
> +
> +#define MSR_HV_SCONTROL			0x000A0010
> +#define MSR_HV_SCTRL_ENABLE		0x0001ULL
> +#define MSR_HV_SCTRL_RSVD_MASK		0xfffffffffffffffeULL
> +
> +#define MSR_HV_SIEFP			0x000A0012
> +#define MSR_HV_SIEFP_ENABLE		0x0001ULL
> +#define MSR_HV_SIEFP_RSVD_MASK		0x0ffeULL
> +#define MSR_HV_SIEFP_PGSHIFT		12
> +
> +#define MSR_HV_SIMP			0x000A0013
> +#define MSR_HV_SIMP_ENABLE		0x0001ULL
> +#define MSR_HV_SIMP_RSVD_MASK		0x0ffeULL
> +#define MSR_HV_SIMP_PGSHIFT		12
> +
> +#define MSR_HV_EOM			0x000A0014
> +
> +#define MSR_HV_SINT0			0x000A0000
> +#define MSR_HV_SINT_VECTOR_MASK		0x00ffULL
> +#define MSR_HV_SINT_RSVD1_MASK		0xff00ULL
> +#define MSR_HV_SINT_MASKED		0x00010000ULL
> +#define MSR_HV_SINT_AUTOEOI		0x00000000ULL
> +#define MSR_HV_SINT_RSVD2_MASK		0xfffffffffffc0000ULL
> +#define MSR_HV_SINT_RSVD_MASK		(MSR_HV_SINT_RSVD1_MASK |	\
> +					 MSR_HV_SINT_RSVD2_MASK)
> +
> +#define MSR_HV_STIMER0_CONFIG		0x400000b0
> +#define MSR_HV_STIMER_CFG_ENABLE	0x0001ULL
> +#define MSR_HV_STIMER_CFG_PERIODIC	0x0002ULL
> +#define MSR_HV_STIMER_CFG_LAZY		0x0004ULL
> +#define MSR_HV_STIMER_CFG_AUTOEN	0x0008ULL
> +#define MSR_HV_STIMER_CFG_SINT_MASK	0x000f0000ULL
> +#define MSR_HV_STIMER_CFG_SINT_SHIFT	16
> +
> +#define MSR_HV_STIMER0_COUNT		0x400000b1
> +
> +/*
> + * CPUID leaves
> + */
> +
> +#define CPUID_LEAF_HV_MAXLEAF		0x40000000
> +
> +#define CPUID_LEAF_HV_INTERFACE		0x40000001
> +#define CPUID_HV_IFACE_HYPERV		0x31237648	/* HV#1 */
> +
> +#define CPUID_LEAF_HV_IDENTITY		0x00000100
> +
> +#define CPUID_LEAF_HV_FEATURES		0x00000200
> +/* EAX: features include/hyperv.h CPUID_HV_MSR */
> +/* ECX: power management features */
> +#define CPUPM_HV_CSTATE_MASK		0x000f	/* deepest C-state */
> +#define CPUPM_HV_C3_HPET		0x0010	/* C3 requires HPET */
> +#define CPUPM_HV_CSTATE(f)		((f) & CPUPM_HV_CSTATE_MASK)
> +/* EDX: features3 */
> +#define CPUID3_HV_MWAIT			0x0001	/* MWAIT */
> +#define CPUID3_HV_XMM_HYPERCALL		0x0010	/* Hypercall input through
> +						 * XMM regs */
> +#define CPUID3_HV_GUEST_IDLE		0x0020	/* guest idle */
> +#define CPUID3_HV_NUMA			0x0080	/* NUMA distance query */
> +#define CPUID3_HV_TIME_FREQ		0x0100	/* timer frequency query
> +						 * (TSC, LAPIC) */
> +#define CPUID3_HV_MSR_CRASH		0x0400	/* MSRs for guest crash */
> +
> +#define CPUID_LEAF_HV_RECOMMENDS	0x00000201
> +#define CPUID_LEAF_HV_LIMITS		0x40000005
> +#define CPUID_LEAF_HV_HWFEATURES	0x40000006
> +
> +/*
> + * Hyper-V Monitor Notification Facility
> + */
> +struct hyperv_mon_param {
> +	uint32_t	mp_connid;
> +	uint16_t	mp_evtflag_ofs;
> +	uint16_t	mp_rsvd;
> +} __packed;
> +
> +/*
> + * Hyper-V message types
> + */
> +#define HYPERV_MSGTYPE_NONE		0
> +#define HYPERV_MSGTYPE_CHANNEL		1
> +#define HYPERV_MSGTYPE_TIMER_EXPIRED	0x80000010
> +
> +/*
> + * Hypercall status codes
> + */
> +#define HYPERCALL_STATUS_SUCCESS	0x0000
> +
> +/*
> + * Hypercall input values
> + */
> +#define HYPERCALL_POST_MESSAGE		0x005c
> +#define HYPERCALL_SIGNAL_EVENT		0x005d
> +
> +/*
> + * Hypercall input parameters
> + */
> +#define HYPERCALL_PARAM_ALIGN		8
> +#if 0
> +/*
> + * XXX
> + * <<Hypervisor Top Level Functional Specification 4.0b>> requires
> + * input parameters size to be multiple of 8, however, many post
> + * message input parameters do _not_ meet this requirement.
> + */
> +#define HYPERCALL_PARAM_SIZE_ALIGN	8
> +#endif
> +
> +/*
> + * HYPERCALL_POST_MESSAGE
> + */
> +#define HYPERCALL_POSTMSGIN_DSIZE_MAX	240
> +#define HYPERCALL_POSTMSGIN_SIZE	256
> +
> +struct hypercall_postmsg_in {
> +	uint32_t	hc_connid;
> +	uint32_t	hc_rsvd;
> +	uint32_t	hc_msgtype;	/* HYPERV_MSGTYPE_ */
> +	uint32_t	hc_dsize;
> +	uint8_t		hc_data[HYPERCALL_POSTMSGIN_DSIZE_MAX];
> +} __packed;
> +CTASSERT(sizeof(struct hypercall_postmsg_in) == HYPERCALL_POSTMSGIN_SIZE);
> +
> +/*
> + * HYPERCALL_SIGNAL_EVENT
> + *
> + * struct hyperv_mon_param.
> + */
> +
> +#endif	/* !_HYPERV_REG_H_ */
> +/*- SPDX-License-Identifier: BSD-2-Clause-FreeBSD
> + * Copyright (c) 2022 Microsoft Corp.
> + * All rights reserved.
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions
> + * are met:
> + * 1. Redistributions of source code must retain the above copyright
> + *    notice unmodified, this list of conditions, and the following
> + *    disclaimer.
> + * 2. Redistributions in binary form must reproduce the above copyright
> + *    notice, this list of conditions and the following disclaimer in the
> + *    documentation and/or other materials provided with the distribution.
> + *
> + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
> + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
> + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
> + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
> + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
> + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + *
> + * $FreeBSD$
> + */
> +
> +#ifndef _HYPERV_REG_H_
> +#define _HYPERV_REG_H_
> +
> +#include <sys/param.h>
> +#include <sys/systm.h>
> +
> +/*
> + * Hyper-V Synthetic MSRs
> + */
> +
> +#define MSR_HV_GUEST_OS_ID		0x00090002
> +#define MSR_HV_GUESTID_BUILD_MASK	0xffffULL
> +#define MSR_HV_GUESTID_VERSION_MASK	0x0000ffffffff0000ULL
> +#define MSR_HV_GUESTID_VERSION_SHIFT	16
> +#define MSR_HV_GUESTID_OSID_MASK	0x00ff000000000000ULL
> +#define MSR_HV_GUESTID_OSID_SHIFT	48
> +#define MSR_HV_GUESTID_OSTYPE_MASK	0x7f00000000000000ULL
> +#define MSR_HV_GUESTID_OSTYPE_SHIFT	56
> +#define MSR_HV_GUESTID_OPENSRC		0x8000000000000000ULL
> +#define MSR_HV_GUESTID_OSTYPE_LINUX	\
> +	((0x01ULL << MSR_HV_GUESTID_OSTYPE_SHIFT) | MSR_HV_GUESTID_OPENSRC)
> +#define MSR_HV_GUESTID_OSTYPE_FREEBSD	\
> +	((0x02ULL << MSR_HV_GUESTID_OSTYPE_SHIFT) | MSR_HV_GUESTID_OPENSRC)
> +
> +#define MSR_HV_HYPERCALL		0x40000001
> +#define MSR_HV_HYPERCALL_ENABLE		0x0001ULL
> +#define MSR_HV_HYPERCALL_RSVD_MASK	0x0ffeULL
> +#define MSR_HV_HYPERCALL_PGSHIFT	12
> +
> +#define MSR_HV_VP_INDEX			0x00090003
> +
> +#define MSR_HV_REFERENCE_TSC		0x40000021
> +#define MSR_HV_REFTSC_ENABLE		0x0001ULL
> +#define MSR_HV_REFTSC_RSVD_MASK		0x0ffeULL
> +#define MSR_HV_REFTSC_PGSHIFT		12
> +
> +#define MSR_HV_SCONTROL			0x000A0010
> +#define MSR_HV_SCTRL_ENABLE		0x0001ULL
> +#define MSR_HV_SCTRL_RSVD_MASK		0xfffffffffffffffeULL
> +
> +#define MSR_HV_SIEFP			0x000A0012
> +#define MSR_HV_SIEFP_ENABLE		0x0001ULL
> +#define MSR_HV_SIEFP_RSVD_MASK		0x0ffeULL
> +#define MSR_HV_SIEFP_PGSHIFT		12
> +
> +#define MSR_HV_SIMP			0x000A0013
> +#define MSR_HV_SIMP_ENABLE		0x0001ULL
> +#define MSR_HV_SIMP_RSVD_MASK		0x0ffeULL
> +#define MSR_HV_SIMP_PGSHIFT		12
> +
> +#define MSR_HV_EOM			0x000A0014
> +
> +#define MSR_HV_SINT0			0x000A0000
> +#define MSR_HV_SINT_VECTOR_MASK		0x00ffULL
> +#define MSR_HV_SINT_RSVD1_MASK		0xff00ULL
> +#define MSR_HV_SINT_MASKED		0x00010000ULL
> +#define MSR_HV_SINT_AUTOEOI		0x00000000ULL
> +#define MSR_HV_SINT_RSVD2_MASK		0xfffffffffffc0000ULL
> +#define MSR_HV_SINT_RSVD_MASK		(MSR_HV_SINT_RSVD1_MASK |	\
> +					 MSR_HV_SINT_RSVD2_MASK)
> +
> +#define MSR_HV_STIMER0_CONFIG		0x400000b0
> +#define MSR_HV_STIMER_CFG_ENABLE	0x0001ULL
> +#define MSR_HV_STIMER_CFG_PERIODIC	0x0002ULL
> +#define MSR_HV_STIMER_CFG_LAZY		0x0004ULL
> +#define MSR_HV_STIMER_CFG_AUTOEN	0x0008ULL
> +#define MSR_HV_STIMER_CFG_SINT_MASK	0x000f0000ULL
> +#define MSR_HV_STIMER_CFG_SINT_SHIFT	16
> +
> +#define MSR_HV_STIMER0_COUNT		0x400000b1
> +
> +/*
> + * CPUID leaves
> + */
> +
> +#define CPUID_LEAF_HV_MAXLEAF		0x40000000
> +
> +#define CPUID_LEAF_HV_INTERFACE		0x40000001
> +#define CPUID_HV_IFACE_HYPERV		0x31237648	/* HV#1 */
> +
> +#define CPUID_LEAF_HV_IDENTITY		0x00000100
> +
> +#define CPUID_LEAF_HV_FEATURES		0x00000200
> +/* EAX: features include/hyperv.h CPUID_HV_MSR */
> +/* ECX: power management features */
> +#define CPUPM_HV_CSTATE_MASK		0x000f	/* deepest C-state */
> +#define CPUPM_HV_C3_HPET		0x0010	/* C3 requires HPET */
> +#define CPUPM_HV_CSTATE(f)		((f) & CPUPM_HV_CSTATE_MASK)
> +/* EDX: features3 */
> +#define CPUID3_HV_MWAIT			0x0001	/* MWAIT */
> +#define CPUID3_HV_XMM_HYPERCALL		0x0010	/* Hypercall input through
> +						 * XMM regs */
> +#define CPUID3_HV_GUEST_IDLE		0x0020	/* guest idle */
> +#define CPUID3_HV_NUMA			0x0080	/* NUMA distance query */
> +#define CPUID3_HV_TIME_FREQ		0x0100	/* timer frequency query
> +						 * (TSC, LAPIC) */
> +#define CPUID3_HV_MSR_CRASH		0x0400	/* MSRs for guest crash */
> +
> +#define CPUID_LEAF_HV_RECOMMENDS	0x00000201
> +#define CPUID_LEAF_HV_LIMITS		0x40000005
> +#define CPUID_LEAF_HV_HWFEATURES	0x40000006
> +
> +/*
> + * Hyper-V Monitor Notification Facility
> + */
> +struct hyperv_mon_param {
> +	uint32_t	mp_connid;
> +	uint16_t	mp_evtflag_ofs;
> +	uint16_t	mp_rsvd;
> +} __packed;
> +
> +/*
> + * Hyper-V message types
> + */
> +#define HYPERV_MSGTYPE_NONE		0
> +#define HYPERV_MSGTYPE_CHANNEL		1
> +#define HYPERV_MSGTYPE_TIMER_EXPIRED	0x80000010
> +
> +/*
> + * Hypercall status codes
> + */
> +#define HYPERCALL_STATUS_SUCCESS	0x0000
> +
> +/*
> + * Hypercall input values
> + */
> +#define HYPERCALL_POST_MESSAGE		0x005c
> +#define HYPERCALL_SIGNAL_EVENT		0x005d
> +
> +/*
> + * Hypercall input parameters
> + */
> +#define HYPERCALL_PARAM_ALIGN		8
> +#if 0
> +/*
> + * XXX
> + * <<Hypervisor Top Level Functional Specification 4.0b>> requires
> + * input parameters size to be multiple of 8, however, many post
> + * message input parameters do _not_ meet this requirement.
> + */
> +#define HYPERCALL_PARAM_SIZE_ALIGN	8
> +#endif
> +
> +/*
> + * HYPERCALL_POST_MESSAGE
> + */
> +#define HYPERCALL_POSTMSGIN_DSIZE_MAX	240
> +#define HYPERCALL_POSTMSGIN_SIZE	256
> +
> +struct hypercall_postmsg_in {
> +	uint32_t	hc_connid;
> +	uint32_t	hc_rsvd;
> +	uint32_t	hc_msgtype;	/* HYPERV_MSGTYPE_ */
> +	uint32_t	hc_dsize;
> +	uint8_t		hc_data[HYPERCALL_POSTMSGIN_DSIZE_MAX];
> +} __packed;
> +CTASSERT(sizeof(struct hypercall_postmsg_in) == HYPERCALL_POSTMSGIN_SIZE);
> +
> +/*
> + * HYPERCALL_SIGNAL_EVENT
> + *
> + * struct hyperv_mon_param.
> + */
> +
> +#endif	/* !_HYPERV_REG_H_ */
> diff --git a/sys/dev/hyperv/vmbus/aarch64/vmbus_aarch64.c b/sys/dev/hyperv/vmbus/aarch64/vmbus_aarch64.c
> new file mode 100644
> index 000000000000..ba4d8c9bc36e
> --- /dev/null
> +++ b/sys/dev/hyperv/vmbus/aarch64/vmbus_aarch64.c
> @@ -0,0 +1,314 @@
> +/*- SPDX-License-Identifier: BSD-2-Clause-FreeBSD
> + * Copyright (c) 2009-2012,2016-2017, 2022 Microsoft Corp.
> + * Copyright (c) 2012 NetApp Inc.
> + * Copyright (c) 2012 Citrix Inc.
> + * All rights reserved.
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions
> + * are met:
> + * 1. Redistributions of source code must retain the above copyright
> + *    notice unmodified, this list of conditions, and the following
> + *    disclaimer.
> + * 2. Redistributions in binary form must reproduce the above copyright
> + *    notice, this list of conditions and the following disclaimer in the
> + *    documentation and/or other materials provided with the distribution.
> + *
> + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
> + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
> + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
> + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
> + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
> + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + */
> +
> +/*
> + * VM Bus Driver Implementation
> + */
> +
> +#include <sys/cdefs.h>
> +__FBSDID("$FreeBSD$");
> +
> +#include <sys/param.h>
> +#include <sys/bus.h>
> +#include <sys/kernel.h>
> +#include <sys/linker.h>
> +#include <sys/lock.h>
> +#include <sys/malloc.h>
> +#include <sys/module.h>
> +#include <sys/mutex.h>
> +#include <sys/sbuf.h>
> +#include <sys/smp.h>
> +#include <sys/sysctl.h>
> +#include <sys/systm.h>
> +#include <sys/taskqueue.h>
> +
> +#include <vm/vm.h>
> +#include <vm/vm_param.h>
> +#include <vm/pmap.h>
> +
> +#include <machine/bus.h>
> +#include <machine/metadata.h>
> +#include <machine/md_var.h>
> +#include <machine/resource.h>
> +#include <contrib/dev/acpica/include/acpi.h>
> +#include <dev/acpica/acpivar.h>
> +
> +#include <dev/hyperv/include/hyperv.h>
> +#include <dev/hyperv/include/vmbus_xact.h>
> +#include <dev/hyperv/vmbus/hyperv_var.h>
> +#include <dev/hyperv/vmbus/vmbus_reg.h>
> +#include <dev/hyperv/vmbus/vmbus_var.h>
> +#include <dev/hyperv/vmbus/vmbus_chanvar.h>
> +#include <dev/hyperv/vmbus/aarch64/hyperv_machdep.h>
> +#include <dev/hyperv/vmbus/aarch64/hyperv_reg.h>
> +#include "acpi_if.h"
> +#include "pcib_if.h"
> +#include "vmbus_if.h"
> +
> +static int vmbus_handle_intr_new(void *);
> +
> +void vmbus_handle_timer_intr1(struct vmbus_message *msg_base,
> +    struct trapframe *frame);
> +void vmbus_synic_setup1(void *xsc);
> +void vmbus_synic_teardown1(void);
> +int vmbus_setup_intr1(struct vmbus_softc *sc);
> +void vmbus_intr_teardown1(struct vmbus_softc *sc);
> +
> +void
> +vmbus_handle_timer_intr1(struct vmbus_message *msg_base,
> +    struct trapframe *frame)
> +{
> +	// do nothing for arm64, as we are using generic timer
> +	return;
> +}
> +
> +static int
> +vmbus_handle_intr_new(void *arg)
> +{
> +	vmbus_handle_intr(NULL);
> +	return (FILTER_HANDLED);
> +}
> +
> +void
> +vmbus_synic_setup1(void *xsc)
> +{
> +	return;
> +}
> +
> +void
> +vmbus_synic_teardown1(void)
> +{
> +	return;
> +}
> +
> +int
> +vmbus_setup_intr1(struct vmbus_softc *sc)
> +{
> +	int err;
> +	struct intr_map_data_acpi *irq_data;
> +
> +	sc->ires = bus_alloc_resource_any(device_get_parent(sc->vmbus_dev),
> +	    SYS_RES_IRQ, &sc->vector, RF_ACTIVE | RF_SHAREABLE);
> +	if (sc->ires == NULL) {
> +		device_printf(sc->vmbus_dev, "bus_alloc_resouce_any failed\n");
> +		return (ENXIO);
> +	} else {
> +		device_printf(sc->vmbus_dev, "irq 0x%lx, vector %d end 0x%lx\n",
> +		    (uint64_t)rman_get_start(sc->ires), sc->vector,
> +		    (uint64_t)rman_get_end(sc->ires));
> +	}
> +	err = bus_setup_intr(sc->vmbus_dev, sc->ires, INTR_TYPE_MISC,
> +	    vmbus_handle_intr_new, NULL, sc, &sc->icookie);
> +	if (err) {
> +		device_printf(sc->vmbus_dev, "failed to setup IRQ %d\n", err);
> +		return (err);
> +	}
> +	irq_data = (struct intr_map_data_acpi *)rman_get_virtual(sc->ires);
> +	device_printf(sc->vmbus_dev, "the irq %u\n", irq_data->irq);
> +	sc->vmbus_idtvec = irq_data->irq;
> +	return 0;
> +}
> +
> +void
> +vmbus_intr_teardown1(struct vmbus_softc *sc)
> +{
> +	int cpu;
> +
> +	sc->vmbus_idtvec = -1;
> +	bus_teardown_intr(sc->vmbus_dev, sc->ires, sc->icookie);
> +
> +	CPU_FOREACH(cpu) {
> +		if (VMBUS_PCPU_GET(sc, event_tq, cpu) != NULL) {
> +			taskqueue_free(VMBUS_PCPU_GET(sc, event_tq, cpu));
> +			VMBUS_PCPU_GET(sc, event_tq, cpu) = NULL;
> +		}
> +		if (VMBUS_PCPU_GET(sc, message_tq, cpu) != NULL) {
> +			taskqueue_drain(VMBUS_PCPU_GET(sc, message_tq, cpu),
> +			    VMBUS_PCPU_PTR(sc, message_task, cpu));
> +			taskqueue_free(VMBUS_PCPU_GET(sc, message_tq, cpu));
> +			VMBUS_PCPU_GET(sc, message_tq, cpu) = NULL;
> +		}
> +	}
> +}
> +/*- SPDX-License-Identifier: BSD-2-Clause-FreeBSD
> + * Copyright (c) 2009-2012,2016-2017, 2022 Microsoft Corp.
> + * Copyright (c) 2012 NetApp Inc.
> + * Copyright (c) 2012 Citrix Inc.
> + * All rights reserved.
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions
> + * are met:
> + * 1. Redistributions of source code must retain the above copyright
> + *    notice unmodified, this list of conditions, and the following
> + *    disclaimer.
> + * 2. Redistributions in binary form must reproduce the above copyright
> + *    notice, this list of conditions and the following disclaimer in the
> + *    documentation and/or other materials provided with the distribution.
> + *
> + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
> + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
> + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
> + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
> + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
> + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + */
> +
> +/*
> + * VM Bus Driver Implementation
> + */
> +
> *** 125 LINES SKIPPED ***
>