Add ARM64-specific code to set up and handle the interrupts
generated by Hyper-V for VMbus messages and for stimer expiration.
This code is architecture dependent and is mostly driven by
architecture independent code in the VMbus driver and the
Hyper-V timer clocksource driver.
This code is built only when CONFIG_HYPERV is enabled.
Signed-off-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
---
arch/arm64/hyperv/Makefile | 2 +-
arch/arm64/hyperv/mshyperv.c | 133 ++++++++++++++++++++++++++++++++++++++
arch/arm64/include/asm/mshyperv.h | 70 ++++++++++++++++++++
3 files changed, 204 insertions(+), 1 deletion(-)
create mode 100644 arch/arm64/hyperv/mshyperv.c
diff --git a/arch/arm64/hyperv/Makefile b/arch/arm64/hyperv/Makefile
index 1697d30..87c31c0 100644
--- a/arch/arm64/hyperv/Makefile
+++ b/arch/arm64/hyperv/Makefile
@@ -1,2 +1,2 @@
# SPDX-License-Identifier: GPL-2.0
-obj-y := hv_core.o
+obj-y := hv_core.o mshyperv.o
diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c
new file mode 100644
index 0000000..be2cd2f
--- /dev/null
+++ b/arch/arm64/hyperv/mshyperv.c
@@ -0,0 +1,133 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Core routines for interacting with Microsoft's Hyper-V hypervisor,
+ * including setting up VMbus and STIMER interrupts, and handling
+ * crashes and kexecs. These interactions are through a set of
+ * static "handler" variables set by the architecture independent
+ * VMbus and STIMER drivers.
+ *
+ * Copyright (C) 2019, Microsoft, Inc.
+ *
+ * Author : Michael Kelley <mikelley@xxxxxxxxxxxxx>
+ */
+
+#include <linux/types.h>
+#include <linux/export.h>
+#include <linux/interrupt.h>
+#include <linux/kexec.h>
+#include <linux/acpi.h>
+#include <linux/ptrace.h>
+#include <asm/hyperv-tlfs.h>
+#include <asm/mshyperv.h>
+
+static void (*vmbus_handler)(void);
+static void (*hv_stimer0_handler)(void);
+
+static int vmbus_irq;
+static long __percpu *vmbus_evt;
+static long __percpu *stimer0_evt;
+
+irqreturn_t hyperv_vector_handler(int irq, void *dev_id)
+{
+ vmbus_handler();
+ return IRQ_HANDLED;
+}
+
+/* Must be done just once */
+int hv_setup_vmbus_irq(int irq, void (*handler)(void))
+{
+ int result;
+
+ vmbus_handler = handler;
+
+ vmbus_evt = alloc_percpu(long);
+ result = request_percpu_irq(irq, hyperv_vector_handler,
+ "Hyper-V VMbus", vmbus_evt);
+ if (result) {
+ pr_err("Can't request Hyper-V VMBus IRQ %d. Error %d",
+ irq, result);
+ free_percpu(vmbus_evt);
+ return result;
+ }
+
+ vmbus_irq = irq;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hv_setup_vmbus_irq);
+
+/* Must be done just once */
+void hv_remove_vmbus_irq(void)
+{
+ if (vmbus_irq) {
+ free_percpu_irq(vmbus_irq, vmbus_evt);
+ free_percpu(vmbus_evt);
+ }
+}
+EXPORT_SYMBOL_GPL(hv_remove_vmbus_irq);
+
+/* Must be done by each CPU */
+void hv_enable_vmbus_irq(void)
+{
+ enable_percpu_irq(vmbus_irq, 0);
+}
+EXPORT_SYMBOL_GPL(hv_enable_vmbus_irq);
+
+/* Must be done by each CPU */
+void hv_disable_vmbus_irq(void)
+{
+ disable_percpu_irq(vmbus_irq);
+}
+EXPORT_SYMBOL_GPL(hv_disable_vmbus_irq);
+
+/* Routines to do per-architecture handling of STIMER0 when in Direct Mode */
+
+static irqreturn_t hv_stimer0_vector_handler(int irq, void *dev_id)
+{
+ if (hv_stimer0_handler)
+ hv_stimer0_handler();
+ return IRQ_HANDLED;
+}
+
+int hv_setup_stimer0_irq(int *irq, int *vector, void (*handler)(void))
+{
+ int localirq;
+ int result;
+
+ localirq = acpi_register_gsi(NULL, HV_STIMER0_INTID,
+ ACPI_EDGE_SENSITIVE, ACPI_ACTIVE_HIGH);
+ if (localirq <= 0) {
+ pr_err("Can't register Hyper-V stimer0 GSI. Error %d",
+ localirq);
+ *irq = 0;
+ return -1;
+ }
+ stimer0_evt = alloc_percpu(long);
+ result = request_percpu_irq(localirq, hv_stimer0_vector_handler,
+ "Hyper-V stimer0", stimer0_evt);
+ if (result) {
+ pr_err("Can't request Hyper-V stimer0 IRQ %d. Error %d",
+ localirq, result);
+ free_percpu(stimer0_evt);
+ acpi_unregister_gsi(localirq);
+ *irq = 0;
+ return result;
+ }
+
+ hv_stimer0_handler = handler;
+ *vector = HV_STIMER0_INTID;
+ *irq = localirq;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hv_setup_stimer0_irq);
+
+void hv_remove_stimer0_irq(int irq)
+{
+ hv_stimer0_handler = NULL;
+ if (irq) {
+ free_percpu_irq(irq, stimer0_evt);
+ free_percpu(stimer0_evt);
+ acpi_unregister_gsi(irq);
+ }
+}
+EXPORT_SYMBOL_GPL(hv_remove_stimer0_irq);
diff --git a/arch/arm64/include/asm/mshyperv.h b/arch/arm64/include/asm/mshyperv.h
index b17d4a1..2ea64e54 100644
--- a/arch/arm64/include/asm/mshyperv.h
+++ b/arch/arm64/include/asm/mshyperv.h
@@ -23,6 +23,7 @@
#include <linux/clocksource.h>
#include <linux/irq.h>
#include <linux/irqdesc.h>
+#include <linux/sched_clock.h>
#include <linux/arm-smccc.h>
#include <asm/hyperv-tlfs.h>
@@ -80,6 +81,75 @@ static inline void hv_set_synint_state(u32 sint_num, u64 val)
(val = hv_get_vpreg(HV_REGISTER_SINT0 + sint_num))
+/*
+ * Define the INTID used by STIMER0 Direct Mode interrupts. This
+ * value can't come from ACPI tables because it is needed before
+ * the Linux ACPI subsystem is initialized.
+ */
+#define HV_STIMER0_INTID 31
+
+/*
+ * Use the Hyper-V provided stimer0 as the timer that is made
+ * available to the architecture independent Hyper-V drivers.
+ */
+static inline void hv_init_timer(u32 timer, u64 tick)
+{
+ hv_set_vpreg(HV_REGISTER_STIMER0_COUNT + (2*timer), tick);
+}
+
+static inline void hv_init_timer_config(u32 timer, u64 val)
+{
+ hv_set_vpreg(HV_REGISTER_STIMER0_CONFIG + (2*timer), val);
+}
+
+#define hv_get_time_ref_count(val) \
+ (val = hv_get_vpreg(HV_REGISTER_TIME_REFCOUNT))
+#define hv_get_reference_tsc(val) \
+ (val = hv_get_vpreg(HV_REGISTER_REFERENCE_TSC))
+
+static inline void hv_set_reference_tsc(u64 val)
+{
+ hv_set_vpreg(HV_REGISTER_REFERENCE_TSC, val);
+}
+
+#define hv_set_clocksource_vdso(val) \
+ ((val).vdso_clock_mode = VDSO_CLOCKMODE_NONE)
+
+static inline void hv_enable_vdso_clocksource(void) {}
+
+static inline void hv_enable_stimer0_percpu_irq(int irq)
+{
+ enable_percpu_irq(irq, 0);
+}
+
+static inline void hv_disable_stimer0_percpu_irq(int irq)
+{
+ disable_percpu_irq(irq);
+}
+
+static inline u64 hv_get_raw_timer(void)
+{
+ return arch_timer_read_counter();
+}
+
+static inline void hv_setup_sched_clock(void *sched_clock)
+{
+ /*
+ * The Hyper-V sched clock read function returns nanoseconds,
+ * not the normal 100ns units of the Hyper-V synthetic clock,
+ * so specify 1 GHz here as the rate.
+ */
+ sched_clock_register(sched_clock, 64, NSEC_PER_SEC);
+}
+
+extern int vmbus_interrupt;
+
+static inline int hv_get_vector(void)
+{
+ return vmbus_interrupt;
+}
+
+
/* SMCCC hypercall parameters */
#define HV_SMCCC_FUNC_NUMBER 1
#define HV_FUNC_ID ARM_SMCCC_CALL_VAL( \
--
1.8.3.1
