From 6b48cb5f8347bc0153ff1d7b075db92e6723ffdb Mon Sep 17 00:00:00 2001 From: "K. Y. Srinivasan" Date: Wed, 16 May 2018 14:53:30 -0700 Subject: X86/Hyper-V: Enlighten APIC access Hyper-V supports MSR based APIC access; implement the enlightenment. Signed-off-by: K. Y. Srinivasan Signed-off-by: Thomas Gleixner Reviewed-by: Michael Kelley Cc: olaf@aepfle.de Cc: sthemmin@microsoft.com Cc: gregkh@linuxfoundation.org Cc: jasowang@redhat.com Cc: Michael.H.Kelley@microsoft.com Cc: hpa@zytor.com Cc: apw@canonical.com Cc: devel@linuxdriverproject.org Cc: vkuznets@redhat.com Link: https://lkml.kernel.org/r/20180516215334.6547-1-kys@linuxonhyperv.com --- arch/x86/hyperv/Makefile | 2 +- arch/x86/hyperv/hv_apic.c | 104 ++++++++++++++++++++++++++++++++++++++++ arch/x86/hyperv/hv_init.c | 5 +- arch/x86/include/asm/mshyperv.h | 4 +- 4 files changed, 112 insertions(+), 3 deletions(-) create mode 100644 arch/x86/hyperv/hv_apic.c diff --git a/arch/x86/hyperv/Makefile b/arch/x86/hyperv/Makefile index 367a8203cfcf..00ce4df01a09 100644 --- a/arch/x86/hyperv/Makefile +++ b/arch/x86/hyperv/Makefile @@ -1 +1 @@ -obj-y := hv_init.o mmu.o +obj-y := hv_init.o mmu.o hv_apic.o diff --git a/arch/x86/hyperv/hv_apic.c b/arch/x86/hyperv/hv_apic.c new file mode 100644 index 000000000000..ca20e31d311c --- /dev/null +++ b/arch/x86/hyperv/hv_apic.c @@ -0,0 +1,104 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Hyper-V specific APIC code. + * + * Copyright (C) 2018, Microsoft, Inc. + * + * Author : K. Y. Srinivasan + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for more + * details. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#ifdef CONFIG_X86_64 +#if IS_ENABLED(CONFIG_HYPERV) + +static u64 hv_apic_icr_read(void) +{ + u64 reg_val; + + rdmsrl(HV_X64_MSR_ICR, reg_val); + return reg_val; +} + +static void hv_apic_icr_write(u32 low, u32 id) +{ + u64 reg_val; + + reg_val = SET_APIC_DEST_FIELD(id); + reg_val = reg_val << 32; + reg_val |= low; + + wrmsrl(HV_X64_MSR_ICR, reg_val); +} + +static u32 hv_apic_read(u32 reg) +{ + u32 reg_val, hi; + + switch (reg) { + case APIC_EOI: + rdmsr(HV_X64_MSR_EOI, reg_val, hi); + return reg_val; + case APIC_TASKPRI: + rdmsr(HV_X64_MSR_TPR, reg_val, hi); + return reg_val; + + default: + return native_apic_mem_read(reg); + } +} + +static void hv_apic_write(u32 reg, u32 val) +{ + switch (reg) { + case APIC_EOI: + wrmsr(HV_X64_MSR_EOI, val, 0); + break; + case APIC_TASKPRI: + wrmsr(HV_X64_MSR_TPR, val, 0); + break; + default: + native_apic_mem_write(reg, val); + } +} + +static void hv_apic_eoi_write(u32 reg, u32 val) +{ + wrmsr(HV_X64_MSR_EOI, val, 0); +} + +void __init hv_apic_init(void) +{ + if (ms_hyperv.hints & HV_X64_APIC_ACCESS_RECOMMENDED) { + pr_info("Hyper-V: Using MSR based APIC access\n"); + apic_set_eoi_write(hv_apic_eoi_write); + apic->read = hv_apic_read; + apic->write = hv_apic_write; + apic->icr_write = hv_apic_icr_write; + apic->icr_read = hv_apic_icr_read; + } +} + +#endif /* CONFIG_HYPERV */ +#endif /* CONFIG_X86_64 */ diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c index cfecc2272f2d..71e50fc2b7ef 100644 --- a/arch/x86/hyperv/hv_init.c +++ b/arch/x86/hyperv/hv_init.c @@ -242,8 +242,9 @@ static int hv_cpu_die(unsigned int cpu) * * 1. Setup the hypercall page. * 2. Register Hyper-V specific clocksource. + * 3. Setup Hyper-V specific APIC entry points. */ -void hyperv_init(void) +void __init hyperv_init(void) { u64 guest_id, required_msrs; union hv_x64_msr_hypercall_contents hypercall_msr; @@ -298,6 +299,8 @@ void hyperv_init(void) hyper_alloc_mmu(); + hv_apic_init(); + /* * Register Hyper-V specific clocksource. */ diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h index b90e79610cf7..162977b82e2e 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -258,7 +258,7 @@ static inline int hv_cpu_number_to_vp_number(int cpu_number) return hv_vp_index[cpu_number]; } -void hyperv_init(void); +void __init hyperv_init(void); void hyperv_setup_mmu_ops(void); void hyper_alloc_mmu(void); void hyperv_report_panic(struct pt_regs *regs, long err); @@ -269,6 +269,7 @@ void hyperv_reenlightenment_intr(struct pt_regs *regs); void set_hv_tscchange_cb(void (*cb)(void)); void clear_hv_tscchange_cb(void); void hyperv_stop_tsc_emulation(void); +void hv_apic_init(void); #else /* CONFIG_HYPERV */ static inline void hyperv_init(void) {} static inline bool hv_is_hyperv_initialized(void) { return false; } @@ -277,6 +278,7 @@ static inline void hyperv_setup_mmu_ops(void) {} static inline void set_hv_tscchange_cb(void (*cb)(void)) {} static inline void clear_hv_tscchange_cb(void) {} static inline void hyperv_stop_tsc_emulation(void) {}; +static inline void hv_apic_init(void) {} static inline struct hv_vp_assist_page *hv_get_vp_assist_page(unsigned int cpu) { return NULL; -- cgit v1.2.3