Hyper-V clock/timer code and data structures are currently mixed in with other code in the ISA independent drivers/hv directory as well as the ISA dependent Hyper-V code under arch/x86. Consolidate this code and data structures into a Hyper-V clocksource driver to better follow the Linux model. In doing so, separate out the ISA dependent portions so the new clocksource driver works for x86 and for the in-process Hyper-V on ARM64 code.
To start, move the existing clockevents code to create the new clocksource driver. Update the VMbus driver to call initialization and cleanup routines since the Hyper-V synthetic timers are not independently enumerated in ACPI.
No behavior is changed and no new functionality is added.
Suggested-by: Marc Zyngier marc.zyngier@arm.com Reviewed-by: Vitaly Kuznetsov vkuznets@redhat.com Signed-off-by: Michael Kelley mikelley@microsoft.com --- MAINTAINERS | 2 + arch/x86/include/asm/hyperv-tlfs.h | 6 ++ arch/x86/kernel/cpu/mshyperv.c | 4 +- drivers/clocksource/Makefile | 1 + drivers/clocksource/hyperv_timer.c | 200 +++++++++++++++++++++++++++++++++++++ drivers/hv/Kconfig | 3 + drivers/hv/hv.c | 156 +---------------------------- drivers/hv/hyperv_vmbus.h | 3 - drivers/hv/vmbus_drv.c | 42 ++++---- include/clocksource/hyperv_timer.h | 27 +++++ 10 files changed, 268 insertions(+), 176 deletions(-) create mode 100644 drivers/clocksource/hyperv_timer.c create mode 100644 include/clocksource/hyperv_timer.h
diff --git a/MAINTAINERS b/MAINTAINERS index a281297..bfde42a 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7313,6 +7313,7 @@ F: arch/x86/include/asm/trace/hyperv.h F: arch/x86/include/asm/hyperv-tlfs.h F: arch/x86/kernel/cpu/mshyperv.c F: arch/x86/hyperv +F: drivers/clocksource/hyperv_timer.c F: drivers/hid/hid-hyperv.c F: drivers/hv/ F: drivers/input/serio/hyperv-keyboard.c @@ -7323,6 +7324,7 @@ F: drivers/uio/uio_hv_generic.c F: drivers/video/fbdev/hyperv_fb.c F: drivers/iommu/hyperv_iommu.c F: net/vmw_vsock/hyperv_transport.c +F: include/clocksource/hyperv_timer.h F: include/linux/hyperv.h F: include/uapi/linux/hyperv.h F: tools/hv/ diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h index cdf44aa..af78cd7 100644 --- a/arch/x86/include/asm/hyperv-tlfs.h +++ b/arch/x86/include/asm/hyperv-tlfs.h @@ -401,6 +401,12 @@ enum HV_GENERIC_SET_FORMAT { #define HV_STATUS_INVALID_CONNECTION_ID 18 #define HV_STATUS_INSUFFICIENT_BUFFERS 19
+/* + * The Hyper-V TimeRefCount register and the TSC + * page provide a guest VM clock with 100ns tick rate + */ +#define HV_CLOCK_HZ (NSEC_PER_SEC/100) + typedef struct _HV_REFERENCE_TSC_PAGE { __u32 tsc_sequence; __u32 res1; diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index 7df29f0..1e5f7a0 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -17,6 +17,7 @@ #include <linux/irq.h> #include <linux/kexec.h> #include <linux/i8253.h> +#include <linux/random.h> #include <asm/processor.h> #include <asm/hypervisor.h> #include <asm/hyperv-tlfs.h> @@ -80,6 +81,7 @@ __visible void __irq_entry hv_stimer0_vector_handler(struct pt_regs *regs) inc_irq_stat(hyperv_stimer0_count); if (hv_stimer0_handler) hv_stimer0_handler(); + add_interrupt_randomness(HYPERV_STIMER0_VECTOR, 0); ack_APIC_irq();
exiting_irq(); @@ -89,7 +91,7 @@ __visible void __irq_entry hv_stimer0_vector_handler(struct pt_regs *regs) int hv_setup_stimer0_irq(int *irq, int *vector, void (*handler)(void)) { *vector = HYPERV_STIMER0_VECTOR; - *irq = 0; /* Unused on x86/x64 */ + *irq = -1; /* Unused on x86/x64 */ hv_stimer0_handler = handler; return 0; } diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 236858f..2b65c5f 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -84,3 +84,4 @@ obj-$(CONFIG_ATCPIT100_TIMER) += timer-atcpit100.o obj-$(CONFIG_RISCV_TIMER) += timer-riscv.o obj-$(CONFIG_CSKY_MP_TIMER) += timer-mp-csky.o obj-$(CONFIG_GX6605S_TIMER) += timer-gx6605s.o +obj-$(CONFIG_HYPERV_TIMER) += hyperv_timer.o diff --git a/drivers/clocksource/hyperv_timer.c b/drivers/clocksource/hyperv_timer.c new file mode 100644 index 0000000..68a28af --- /dev/null +++ b/drivers/clocksource/hyperv_timer.c @@ -0,0 +1,200 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Clocksource driver for the synthetic counter and timers + * provided by the Hyper-V hypervisor to guest VMs, as described + * in the Hyper-V Top Level Functional Spec (TLFS). This driver + * is instruction set architecture independent. + * + * Copyright (C) 2019, Microsoft, Inc. + * + * Author: Michael Kelley mikelley@microsoft.com + */ + +#include <linux/percpu.h> +#include <linux/cpumask.h> +#include <linux/clockchips.h> +#include <linux/mm.h> +#include <clocksource/hyperv_timer.h> +#include <asm/hyperv-tlfs.h> +#include <asm/mshyperv.h> + +static struct clock_event_device __percpu *hv_clock_event; + +/* + * If false, we're using the old mechanism for stimer0 interrupts + * where it sends a VMbus message when it expires. The old + * mechanism is used when running on older versions of Hyper-V + * that don't support Direct Mode. While Hyper-V provides + * four stimer's per CPU, Linux uses only stimer0. + */ +static bool direct_mode_enabled; + +static int stimer0_irq; +static int stimer0_vector; +static int stimer0_message_sint; + +/* + * ISR for when stimer0 is operating in Direct Mode. Direct Mode + * does not use VMbus or any VMbus messages, so process here and not + * in the VMbus driver code. + */ +void hv_stimer0_isr(void) +{ + struct clock_event_device *ce; + + ce = this_cpu_ptr(hv_clock_event); + ce->event_handler(ce); +} +EXPORT_SYMBOL_GPL(hv_stimer0_isr); + +static int hv_ce_set_next_event(unsigned long delta, + struct clock_event_device *evt) +{ + u64 current_tick; + + current_tick = hyperv_cs->read(NULL); + current_tick += delta; + hv_init_timer(0, current_tick); + return 0; +} + +static int hv_ce_shutdown(struct clock_event_device *evt) +{ + hv_init_timer(0, 0); + hv_init_timer_config(0, 0); + if (direct_mode_enabled) + hv_disable_stimer0_percpu_irq(stimer0_irq); + + return 0; +} + +static int hv_ce_set_oneshot(struct clock_event_device *evt) +{ + union hv_stimer_config timer_cfg; + + timer_cfg.as_uint64 = 0; + timer_cfg.enable = 1; + timer_cfg.auto_enable = 1; + if (direct_mode_enabled) { + /* + * When it expires, the timer will directly interrupt + * on the specified hardware vector/IRQ. + */ + timer_cfg.direct_mode = 1; + timer_cfg.apic_vector = stimer0_vector; + hv_enable_stimer0_percpu_irq(stimer0_irq); + } else { + /* + * When it expires, the timer will generate a VMbus message, + * to be handled by the normal VMbus interrupt handler. + */ + timer_cfg.direct_mode = 0; + timer_cfg.sintx = stimer0_message_sint; + } + hv_init_timer_config(0, timer_cfg.as_uint64); + return 0; +} + +/* + * hv_stimer_init - Per-cpu initialization of the clockevent + */ +void hv_stimer_init(unsigned int cpu) +{ + struct clock_event_device *ce; + + /* + * Synthetic timers are always available except on old versions of + * Hyper-V on x86. In that case, just return as Linux will use a + * clocksource based on emulated PIT or LAPIC timer hardware. + */ + if (!(ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE)) + return; + + ce = per_cpu_ptr(hv_clock_event, cpu); + ce->name = "Hyper-V clockevent"; + ce->features = CLOCK_EVT_FEAT_ONESHOT; + ce->cpumask = cpumask_of(cpu); + ce->rating = 1000; + ce->set_state_shutdown = hv_ce_shutdown; + ce->set_state_oneshot = hv_ce_set_oneshot; + ce->set_next_event = hv_ce_set_next_event; + + clockevents_config_and_register(ce, + HV_CLOCK_HZ, + HV_MIN_DELTA_TICKS, + HV_MAX_MAX_DELTA_TICKS); +} +EXPORT_SYMBOL_GPL(hv_stimer_init); + +/* + * hv_stimer_cleanup - Per-cpu cleanup of the clockevent + */ +void hv_stimer_cleanup(unsigned int cpu) +{ + struct clock_event_device *ce; + + /* Turn off clockevent device */ + if (ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE) { + ce = per_cpu_ptr(hv_clock_event, cpu); + hv_ce_shutdown(ce); + } +} +EXPORT_SYMBOL_GPL(hv_stimer_cleanup); + +/* hv_stimer_alloc - Global initialization of the clockevent and stimer0 */ +int hv_stimer_alloc(int sint) +{ + int ret; + + hv_clock_event = alloc_percpu(struct clock_event_device); + if (!hv_clock_event) + return -ENOMEM; + + direct_mode_enabled = ms_hyperv.misc_features & + HV_STIMER_DIRECT_MODE_AVAILABLE; + if (direct_mode_enabled) { + ret = hv_setup_stimer0_irq(&stimer0_irq, &stimer0_vector, + hv_stimer0_isr); + if (ret) { + free_percpu(hv_clock_event); + hv_clock_event = NULL; + return ret; + } + } + + stimer0_message_sint = sint; + return 0; +} +EXPORT_SYMBOL_GPL(hv_stimer_alloc); + +/* hv_stimer_free - Free global resources allocated by hv_stimer_alloc() */ +void hv_stimer_free(void) +{ + if (direct_mode_enabled && (stimer0_irq != 0)) { + hv_remove_stimer0_irq(stimer0_irq); + stimer0_irq = 0; + } + free_percpu(hv_clock_event); + hv_clock_event = NULL; +} +EXPORT_SYMBOL_GPL(hv_stimer_free); + +/* + * Do a global cleanup of clockevents for the cases of kexec and + * vmbus exit + */ +void hv_stimer_global_cleanup(void) +{ + int cpu; + struct clock_event_device *ce; + + if (ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE) { + for_each_present_cpu(cpu) { + ce = per_cpu_ptr(hv_clock_event, cpu); + clockevents_unbind_device(ce, cpu); + } + } + hv_stimer_free(); +} +EXPORT_SYMBOL_GPL(hv_stimer_global_cleanup); diff --git a/drivers/hv/Kconfig b/drivers/hv/Kconfig index 1c1a251..c423e57 100644 --- a/drivers/hv/Kconfig +++ b/drivers/hv/Kconfig @@ -10,6 +10,9 @@ config HYPERV Select this option to run Linux as a Hyper-V client operating system.
+config HYPERV_TIMER + def_bool HYPERV + config HYPERV_TSCPAGE def_bool HYPERV && X86_64
diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c index a1ea482..6188fb7 100644 --- a/drivers/hv/hv.c +++ b/drivers/hv/hv.c @@ -16,6 +16,7 @@ #include <linux/version.h> #include <linux/random.h> #include <linux/clockchips.h> +#include <clocksource/hyperv_timer.h> #include <asm/mshyperv.h> #include "hyperv_vmbus.h"
@@ -23,21 +24,6 @@ struct hv_context hv_context;
/* - * If false, we're using the old mechanism for stimer0 interrupts - * where it sends a VMbus message when it expires. The old - * mechanism is used when running on older versions of Hyper-V - * that don't support Direct Mode. While Hyper-V provides - * four stimer's per CPU, Linux uses only stimer0. - */ -static bool direct_mode_enabled; -static int stimer0_irq; -static int stimer0_vector; - -#define HV_TIMER_FREQUENCY (10 * 1000 * 1000) /* 100ns period */ -#define HV_MAX_MAX_DELTA_TICKS 0xffffffff -#define HV_MIN_DELTA_TICKS 1 - -/* * hv_init - Main initialization routine. * * This routine must be called before any other routines in here are called @@ -47,9 +33,6 @@ int hv_init(void) hv_context.cpu_context = alloc_percpu(struct hv_per_cpu_context); if (!hv_context.cpu_context) return -ENOMEM; - - direct_mode_enabled = ms_hyperv.misc_features & - HV_STIMER_DIRECT_MODE_AVAILABLE; return 0; }
@@ -88,89 +71,6 @@ int hv_post_message(union hv_connection_id connection_id, return status & 0xFFFF; }
-/* - * ISR for when stimer0 is operating in Direct Mode. Direct Mode - * does not use VMbus or any VMbus messages, so process here and not - * in the VMbus driver code. - */ - -static void hv_stimer0_isr(void) -{ - struct hv_per_cpu_context *hv_cpu; - - hv_cpu = this_cpu_ptr(hv_context.cpu_context); - hv_cpu->clk_evt->event_handler(hv_cpu->clk_evt); - add_interrupt_randomness(stimer0_vector, 0); -} - -static int hv_ce_set_next_event(unsigned long delta, - struct clock_event_device *evt) -{ - u64 current_tick; - - WARN_ON(!clockevent_state_oneshot(evt)); - - current_tick = hyperv_cs->read(NULL); - current_tick += delta; - hv_init_timer(0, current_tick); - return 0; -} - -static int hv_ce_shutdown(struct clock_event_device *evt) -{ - hv_init_timer(0, 0); - hv_init_timer_config(0, 0); - if (direct_mode_enabled) - hv_disable_stimer0_percpu_irq(stimer0_irq); - - return 0; -} - -static int hv_ce_set_oneshot(struct clock_event_device *evt) -{ - union hv_stimer_config timer_cfg; - - timer_cfg.as_uint64 = 0; - timer_cfg.enable = 1; - timer_cfg.auto_enable = 1; - if (direct_mode_enabled) { - /* - * When it expires, the timer will directly interrupt - * on the specified hardware vector/IRQ. - */ - timer_cfg.direct_mode = 1; - timer_cfg.apic_vector = stimer0_vector; - hv_enable_stimer0_percpu_irq(stimer0_irq); - } else { - /* - * When it expires, the timer will generate a VMbus message, - * to be handled by the normal VMbus interrupt handler. - */ - timer_cfg.direct_mode = 0; - timer_cfg.sintx = VMBUS_MESSAGE_SINT; - } - hv_init_timer_config(0, timer_cfg.as_uint64); - return 0; -} - -static void hv_init_clockevent_device(struct clock_event_device *dev, int cpu) -{ - dev->name = "Hyper-V clockevent"; - dev->features = CLOCK_EVT_FEAT_ONESHOT; - dev->cpumask = cpumask_of(cpu); - dev->rating = 1000; - /* - * Avoid settint dev->owner = THIS_MODULE deliberately as doing so will - * result in clockevents_config_and_register() taking additional - * references to the hv_vmbus module making it impossible to unload. - */ - - dev->set_state_shutdown = hv_ce_shutdown; - dev->set_state_oneshot = hv_ce_set_oneshot; - dev->set_next_event = hv_ce_set_next_event; -} - - int hv_synic_alloc(void) { int cpu; @@ -199,14 +99,6 @@ int hv_synic_alloc(void) tasklet_init(&hv_cpu->msg_dpc, vmbus_on_msg_dpc, (unsigned long) hv_cpu);
- hv_cpu->clk_evt = kzalloc(sizeof(struct clock_event_device), - GFP_KERNEL); - if (hv_cpu->clk_evt == NULL) { - pr_err("Unable to allocate clock event device\n"); - goto err; - } - hv_init_clockevent_device(hv_cpu->clk_evt, cpu); - hv_cpu->synic_message_page = (void *)get_zeroed_page(GFP_ATOMIC); if (hv_cpu->synic_message_page == NULL) { @@ -229,11 +121,6 @@ int hv_synic_alloc(void) INIT_LIST_HEAD(&hv_cpu->chan_list); }
- if (direct_mode_enabled && - hv_setup_stimer0_irq(&stimer0_irq, &stimer0_vector, - hv_stimer0_isr)) - goto err; - return 0; err: /* @@ -252,7 +139,6 @@ void hv_synic_free(void) struct hv_per_cpu_context *hv_cpu = per_cpu_ptr(hv_context.cpu_context, cpu);
- kfree(hv_cpu->clk_evt); free_page((unsigned long)hv_cpu->synic_event_page); free_page((unsigned long)hv_cpu->synic_message_page); free_page((unsigned long)hv_cpu->post_msg_page); @@ -311,36 +197,9 @@ int hv_synic_init(unsigned int cpu)
hv_set_synic_state(sctrl.as_uint64);
- /* - * Register the per-cpu clockevent source. - */ - if (ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE) - clockevents_config_and_register(hv_cpu->clk_evt, - HV_TIMER_FREQUENCY, - HV_MIN_DELTA_TICKS, - HV_MAX_MAX_DELTA_TICKS); - return 0; -} - -/* - * hv_synic_clockevents_cleanup - Cleanup clockevent devices - */ -void hv_synic_clockevents_cleanup(void) -{ - int cpu; + hv_stimer_init(cpu);
- if (!(ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE)) - return; - - if (direct_mode_enabled) - hv_remove_stimer0_irq(stimer0_irq); - - for_each_present_cpu(cpu) { - struct hv_per_cpu_context *hv_cpu - = per_cpu_ptr(hv_context.cpu_context, cpu); - - clockevents_unbind_device(hv_cpu->clk_evt, cpu); - } + return 0; }
/* @@ -388,14 +247,7 @@ int hv_synic_cleanup(unsigned int cpu) if (channel_found && vmbus_connection.conn_state == CONNECTED) return -EBUSY;
- /* Turn off clockevent device */ - if (ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE) { - struct hv_per_cpu_context *hv_cpu - = this_cpu_ptr(hv_context.cpu_context); - - clockevents_unbind_device(hv_cpu->clk_evt, cpu); - hv_ce_shutdown(hv_cpu->clk_evt); - } + hv_stimer_cleanup(cpu);
hv_get_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h index b8e1ff0..362e70e 100644 --- a/drivers/hv/hyperv_vmbus.h +++ b/drivers/hv/hyperv_vmbus.h @@ -138,7 +138,6 @@ struct hv_per_cpu_context { * per-cpu list of the channels based on their CPU affinity. */ struct list_head chan_list; - struct clock_event_device *clk_evt; };
struct hv_context { @@ -176,8 +175,6 @@ extern int hv_post_message(union hv_connection_id connection_id,
extern int hv_synic_cleanup(unsigned int cpu);
-extern void hv_synic_clockevents_cleanup(void); - /* Interface */
void hv_ringbuffer_pre_init(struct vmbus_channel *channel); diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 92b1874..72d5a7c 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -30,6 +30,7 @@ #include <linux/kdebug.h> #include <linux/efi.h> #include <linux/random.h> +#include <clocksource/hyperv_timer.h> #include "hyperv_vmbus.h"
struct vmbus_dynid { @@ -955,17 +956,6 @@ static void vmbus_onmessage_work(struct work_struct *work) kfree(ctx); }
-static void hv_process_timer_expiration(struct hv_message *msg, - struct hv_per_cpu_context *hv_cpu) -{ - struct clock_event_device *dev = hv_cpu->clk_evt; - - if (dev->event_handler) - dev->event_handler(dev); - - vmbus_signal_eom(msg, HVMSG_TIMER_EXPIRED); -} - void vmbus_on_msg_dpc(unsigned long data) { struct hv_per_cpu_context *hv_cpu = (void *)data; @@ -1159,9 +1149,10 @@ static void vmbus_isr(void)
/* Check if there are actual msgs to be processed */ if (msg->header.message_type != HVMSG_NONE) { - if (msg->header.message_type == HVMSG_TIMER_EXPIRED) - hv_process_timer_expiration(msg, hv_cpu); - else + if (msg->header.message_type == HVMSG_TIMER_EXPIRED) { + hv_stimer0_isr(); + vmbus_signal_eom(msg, HVMSG_TIMER_EXPIRED); + } else tasklet_schedule(&hv_cpu->msg_dpc); }
@@ -1263,14 +1254,19 @@ static int vmbus_bus_init(void) ret = hv_synic_alloc(); if (ret) goto err_alloc; + + ret = hv_stimer_alloc(VMBUS_MESSAGE_SINT); + if (ret < 0) + goto err_alloc; + /* - * Initialize the per-cpu interrupt state and - * connect to the host. + * Initialize the per-cpu interrupt state and stimer state. + * Then connect to the host. */ ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "hyperv/vmbus:online", hv_synic_init, hv_synic_cleanup); if (ret < 0) - goto err_alloc; + goto err_cpuhp; hyperv_cpuhp_online = ret;
ret = vmbus_connect(); @@ -1318,6 +1314,8 @@ static int vmbus_bus_init(void)
err_connect: cpuhp_remove_state(hyperv_cpuhp_online); +err_cpuhp: + hv_stimer_free(); err_alloc: hv_synic_free(); hv_remove_vmbus_irq(); @@ -2064,7 +2062,7 @@ static int vmbus_acpi_add(struct acpi_device *device)
static void hv_kexec_handler(void) { - hv_synic_clockevents_cleanup(); + hv_stimer_global_cleanup(); vmbus_initiate_unload(false); vmbus_connection.conn_state = DISCONNECTED; /* Make sure conn_state is set as hv_synic_cleanup checks for it */ @@ -2075,6 +2073,8 @@ static void hv_kexec_handler(void)
static void hv_crash_handler(struct pt_regs *regs) { + int cpu; + vmbus_initiate_unload(true); /* * In crash handler we can't schedule synic cleanup for all CPUs, @@ -2082,7 +2082,9 @@ static void hv_crash_handler(struct pt_regs *regs) * for kdump. */ vmbus_connection.conn_state = DISCONNECTED; - hv_synic_cleanup(smp_processor_id()); + cpu = smp_processor_id(); + hv_stimer_cleanup(cpu); + hv_synic_cleanup(cpu); hyperv_cleanup(); };
@@ -2131,7 +2133,7 @@ static void __exit vmbus_exit(void) hv_remove_kexec_handler(); hv_remove_crash_handler(); vmbus_connection.conn_state = DISCONNECTED; - hv_synic_clockevents_cleanup(); + hv_stimer_global_cleanup(); vmbus_disconnect(); hv_remove_vmbus_irq(); for_each_online_cpu(cpu) { diff --git a/include/clocksource/hyperv_timer.h b/include/clocksource/hyperv_timer.h new file mode 100644 index 0000000..0cd73f7 --- /dev/null +++ b/include/clocksource/hyperv_timer.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* + * Definitions for the clocksource provided by the Hyper-V + * hypervisor to guest VMs, as described in the Hyper-V Top + * Level Functional Spec (TLFS). + * + * Copyright (C) 2019, Microsoft, Inc. + * + * Author: Michael Kelley mikelley@microsoft.com + */ + +#ifndef __CLKSOURCE_HYPERV_TIMER_H +#define __CLKSOURCE_HYPERV_TIMER_H + +#define HV_MAX_MAX_DELTA_TICKS 0xffffffff +#define HV_MIN_DELTA_TICKS 1 + +/* Routines called by the VMbus driver */ +extern int hv_stimer_alloc(int sint); +extern void hv_stimer_free(void); +extern void hv_stimer_init(unsigned int cpu); +extern void hv_stimer_cleanup(unsigned int cpu); +extern void hv_stimer_global_cleanup(void); +extern void hv_stimer0_isr(void); + +#endif