hv/mod_timer: make timer into an arch-independent module

x86/timer.[ch] was moved to the common directory largely unchanged.

x86 specific code now resides in x86/tsc_deadline_timer.c and its
interface was defined in hw/hw_timer.h. The interface defines two
functions: init_hw_timer() and set_hw_timeout() that provides HW
specific initialization and timer interrupt source.

Other than these two functions, the timer module is largely arch
agnostic.

Tracked-On: #5920
Signed-off-by: Rong Liu <rong2.liu@intel.com>
Reviewed-by: Jason Chen CJ <jason.cj.chen@intel.com>

hypervisor/include/common/timer.h

@@ -0,0 +1,138 @@
+/*
+ * Copyright (C) 2018 Intel Corporation. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef COMMON_TIMER_H
+#define COMMON_TIMER_H
+
+#include <list.h>
+#include <ticks.h>
+
+/**
+ * @brief Timer
+ *
+ * @defgroup timer ACRN Timer
+ * @{
+ */
+
+typedef void (*timer_handle_t)(void *data);
+
+/**
+ * @brief Definition of timer tick mode
+ */
+enum tick_mode {
+	TICK_MODE_ONESHOT = 0,	/**< one-shot mode */
+	TICK_MODE_PERIODIC,	/**< periodic mode */
+};
+
+/**
+ * @brief Definition of timers for per-cpu
+ */
+struct per_cpu_timers {
+	struct list_head timer_list;	/**< it's for runtime active timer list */
+};
+
+/**
+ * @brief Definition of timer
+ */
+struct hv_timer {
+	struct list_head node;		/**< link all timers */
+	enum tick_mode mode;		/**< timer mode: one-shot or periodic */
+	uint64_t fire_tsc;		/**< tsc deadline to interrupt */
+	uint64_t period_in_cycle;	/**< period of the periodic timer in unit of TSC cycles */
+	timer_handle_t func;		/**< callback if time reached */
+	void *priv_data;		/**< func private data */
+};
+
+/* External Interfaces */
+
+/**
+ * @brief Initialize a timer structure.
+ *
+ * @param[in] timer Pointer to timer.
+ * @param[in] func irq callback if time reached.
+ * @param[in] priv_data func private data.
+ * @param[in] fire_tsc tsc deadline to interrupt.
+ * @param[in] mode timer mode.
+ * @param[in] period_in_cycle period of the periodic timer in unit of TSC cycles.
+ *
+ * @remark Don't initialize a timer twice if it has been added to the timer list
+ *         after calling add_timer. If you want to, delete the timer from the list first.
+ *
+ * @return None
+ */
+static inline void initialize_timer(struct hv_timer *timer,
+				timer_handle_t func, void *priv_data,
+				uint64_t fire_tsc, int32_t mode, uint64_t period_in_cycle)
+{
+	if (timer != NULL) {
+		timer->func = func;
+		timer->priv_data = priv_data;
+		timer->fire_tsc = fire_tsc;
+		timer->mode = mode;
+		timer->period_in_cycle = period_in_cycle;
+		INIT_LIST_HEAD(&timer->node);
+	}
+}
+
+/**
+ * @brief Check a timer whether expired.
+ *
+ * @param[in] timer Pointer to timer.
+ *
+ * @retval true if the timer is expired, false otherwise.
+ */
+static inline bool timer_expired(const struct hv_timer *timer)
+{
+	return ((timer->fire_tsc == 0UL) || (cpu_ticks() >= timer->fire_tsc));
+}
+
+/**
+ * @brief Check a timer whether in timer list.
+ *
+ * @param[in] timer Pointer to timer.
+ *
+ * @retval true if the timer is in timer list, false otherwise.
+ */
+static inline bool timer_is_started(const struct hv_timer *timer)
+{
+	return (!list_empty(&timer->node));
+}
+
+/**
+ * @brief Add a timer.
+ *
+ * @param[in] timer Pointer to timer.
+ *
+ * @retval 0 on success
+ * @retval -EINVAL timer has an invalid value
+ *
+ * @remark Don't call it in the timer callback function or interrupt content.
+ */
+int32_t add_timer(struct hv_timer *timer);
+
+/**
+ * @brief Delete a timer.
+ *
+ * @param[in] timer Pointer to timer.
+ *
+ * @return None
+ *
+ * @remark Don't call it in the timer callback function or interrupt content.
+ */
+void del_timer(struct hv_timer *timer);
+
+/**
+ * @brief Initialize timer.
+ *
+ * @return None
+ */
+void timer_init(void);
+
+/**
+ * @}
+ */
+
+#endif /* COMMON_TIMER_H */