diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/Kbuild | 1 | ||||
| -rw-r--r-- | arch/arm64/hyperv/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm64/hyperv/hv_core.c | 129 | ||||
| -rw-r--r-- | arch/arm64/include/asm/hyperv-tlfs.h | 69 | ||||
| -rw-r--r-- | arch/arm64/include/asm/mshyperv.h | 54 |
5 files changed, 255 insertions, 0 deletions
diff --git a/arch/arm64/Kbuild b/arch/arm64/Kbuild index 7b393cfec071..ea7ab4ca81f9 100644 --- a/arch/arm64/Kbuild +++ b/arch/arm64/Kbuild @@ -2,4 +2,5 @@ obj-y += kernel/ mm/ net/ obj-$(CONFIG_KVM) += kvm/ obj-$(CONFIG_XEN) += xen/ +obj-$(subst m,y,$(CONFIG_HYPERV)) += hyperv/ obj-$(CONFIG_CRYPTO) += crypto/ diff --git a/arch/arm64/hyperv/Makefile b/arch/arm64/hyperv/Makefile new file mode 100644 index 000000000000..1697d30ff106 --- /dev/null +++ b/arch/arm64/hyperv/Makefile @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0 +obj-y := hv_core.o diff --git a/arch/arm64/hyperv/hv_core.c b/arch/arm64/hyperv/hv_core.c new file mode 100644 index 000000000000..4c5dc0f51b12 --- /dev/null +++ b/arch/arm64/hyperv/hv_core.c @@ -0,0 +1,129 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Low level utility routines for interacting with Hyper-V. + * + * Copyright (C) 2021, Microsoft, Inc. + * + * Author : Michael Kelley <mikelley@microsoft.com> + */ + +#include <linux/types.h> +#include <linux/export.h> +#include <linux/mm.h> +#include <linux/hyperv.h> +#include <linux/arm-smccc.h> +#include <linux/module.h> +#include <asm-generic/bug.h> +#include <asm/hyperv-tlfs.h> +#include <asm/mshyperv.h> + +/* + * hv_do_hypercall- Invoke the specified hypercall + */ +u64 hv_do_hypercall(u64 control, void *input, void *output) +{ + struct arm_smccc_res res; + u64 input_address; + u64 output_address; + + input_address = input ? virt_to_phys(input) : 0; + output_address = output ? virt_to_phys(output) : 0; + + arm_smccc_1_1_hvc(HV_FUNC_ID, control, + input_address, output_address, &res); + return res.a0; +} +EXPORT_SYMBOL_GPL(hv_do_hypercall); + +/* + * hv_do_fast_hypercall8 -- Invoke the specified hypercall + * with arguments in registers instead of physical memory. + * Avoids the overhead of virt_to_phys for simple hypercalls. + */ + +u64 hv_do_fast_hypercall8(u16 code, u64 input) +{ + struct arm_smccc_res res; + u64 control; + + control = (u64)code | HV_HYPERCALL_FAST_BIT; + + arm_smccc_1_1_hvc(HV_FUNC_ID, control, input, &res); + return res.a0; +} +EXPORT_SYMBOL_GPL(hv_do_fast_hypercall8); + +/* + * Set a single VP register to a 64-bit value. + */ +void hv_set_vpreg(u32 msr, u64 value) +{ + struct arm_smccc_res res; + + arm_smccc_1_1_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, + &res); + + /* + * Something is fundamentally broken in the hypervisor if + * setting a VP register fails. There's really no way to + * continue as a guest VM, so panic. + */ + BUG_ON(!hv_result_success(res.a0)); +} +EXPORT_SYMBOL_GPL(hv_set_vpreg); + +/* + * Get the value of a single VP register. One version + * returns just 64 bits and another returns the full 128 bits. + * The two versions are separate to avoid complicating the + * calling sequence for the more frequently used 64 bit version. + */ + +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); + + /* + * Something is fundamentally broken in the hypervisor if + * getting a VP register fails. There's really no way to + * continue as a guest VM, so panic. + */ + BUG_ON(!hv_result_success(res.a0)); + + result->as64.low = res.a6; + result->as64.high = res.a7; +} +EXPORT_SYMBOL_GPL(hv_get_vpreg_128); + +u64 hv_get_vpreg(u32 msr) +{ + struct hv_get_vp_registers_output output; + + hv_get_vpreg_128(msr, &output); + + return output.as64.low; +} +EXPORT_SYMBOL_GPL(hv_get_vpreg); diff --git a/arch/arm64/include/asm/hyperv-tlfs.h b/arch/arm64/include/asm/hyperv-tlfs.h new file mode 100644 index 000000000000..4d964a7f02ee --- /dev/null +++ b/arch/arm64/include/asm/hyperv-tlfs.h @@ -0,0 +1,69 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* + * This file contains definitions from the Hyper-V Hypervisor Top-Level + * Functional Specification (TLFS): + * https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/reference/tlfs + * + * Copyright (C) 2021, Microsoft, Inc. + * + * Author : Michael Kelley <mikelley@microsoft.com> + */ + +#ifndef _ASM_HYPERV_TLFS_H +#define _ASM_HYPERV_TLFS_H + +#include <linux/types.h> + +/* + * All data structures defined in the TLFS that are shared between Hyper-V + * and a guest VM use Little Endian byte ordering. This matches the default + * byte ordering of Linux running on ARM64, so no special handling is required. + */ + +/* + * These Hyper-V registers provide information equivalent to the CPUID + * instruction on x86/x64. + */ +#define HV_REGISTER_HYPERVISOR_VERSION 0x00000100 /*CPUID 0x40000002 */ +#define HV_REGISTER_FEATURES 0x00000200 /*CPUID 0x40000003 */ +#define HV_REGISTER_ENLIGHTENMENTS 0x00000201 /*CPUID 0x40000004 */ + +/* + * Group C Features. See the asm-generic version of hyperv-tlfs.h + * for a description of Feature Groups. + */ + +/* Crash MSRs available */ +#define HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE BIT(8) + +/* STIMER direct mode is available */ +#define HV_STIMER_DIRECT_MODE_AVAILABLE BIT(13) + +/* + * Synthetic register definitions equivalent to MSRs on x86/x64 + */ +#define HV_REGISTER_CRASH_P0 0x00000210 +#define HV_REGISTER_CRASH_P1 0x00000211 +#define HV_REGISTER_CRASH_P2 0x00000212 +#define HV_REGISTER_CRASH_P3 0x00000213 +#define HV_REGISTER_CRASH_P4 0x00000214 +#define HV_REGISTER_CRASH_CTL 0x00000215 + +#define HV_REGISTER_GUEST_OSID 0x00090002 +#define HV_REGISTER_VP_INDEX 0x00090003 +#define HV_REGISTER_TIME_REF_COUNT 0x00090004 +#define HV_REGISTER_REFERENCE_TSC 0x00090017 + +#define HV_REGISTER_SINT0 0x000A0000 +#define HV_REGISTER_SCONTROL 0x000A0010 +#define HV_REGISTER_SIEFP 0x000A0012 +#define HV_REGISTER_SIMP 0x000A0013 +#define HV_REGISTER_EOM 0x000A0014 + +#define HV_REGISTER_STIMER0_CONFIG 0x000B0000 +#define HV_REGISTER_STIMER0_COUNT 0x000B0001 + +#include <asm-generic/hyperv-tlfs.h> + +#endif diff --git a/arch/arm64/include/asm/mshyperv.h b/arch/arm64/include/asm/mshyperv.h new file mode 100644 index 000000000000..20070a847304 --- /dev/null +++ b/arch/arm64/include/asm/mshyperv.h @@ -0,0 +1,54 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* + * Linux-specific definitions for managing interactions with Microsoft's + * Hyper-V hypervisor. The definitions in this file are specific to + * the ARM64 architecture. See include/asm-generic/mshyperv.h for + * definitions are that architecture independent. + * + * Definitions that are specified in the Hyper-V Top Level Functional + * Spec (TLFS) should not go in this file, but should instead go in + * hyperv-tlfs.h. + * + * Copyright (C) 2021, Microsoft, Inc. + * + * Author : Michael Kelley <mikelley@microsoft.com> + */ + +#ifndef _ASM_MSHYPERV_H +#define _ASM_MSHYPERV_H + +#include <linux/types.h> +#include <linux/arm-smccc.h> +#include <asm/hyperv-tlfs.h> + +/* + * Declare calls to get and set Hyper-V VP register values on ARM64, which + * requires a hypercall. + */ + +void hv_set_vpreg(u32 reg, u64 value); +u64 hv_get_vpreg(u32 reg); +void hv_get_vpreg_128(u32 reg, struct hv_get_vp_registers_output *result); + +static inline void hv_set_register(unsigned int reg, u64 value) +{ + hv_set_vpreg(reg, value); +} + +static inline u64 hv_get_register(unsigned int reg) +{ + return hv_get_vpreg(reg); +} + +/* SMCCC hypercall parameters */ +#define HV_SMCCC_FUNC_NUMBER 1 +#define HV_FUNC_ID ARM_SMCCC_CALL_VAL( \ + ARM_SMCCC_STD_CALL, \ + ARM_SMCCC_SMC_64, \ + ARM_SMCCC_OWNER_VENDOR_HYP, \ + HV_SMCCC_FUNC_NUMBER) + +#include <asm-generic/mshyperv.h> + +#endif |