embox

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/**
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 * @file
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 *
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 * @date
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 * @author
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 */
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#include <hal/clock.h>
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#include <kernel/time/clock_source.h>
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#include <kernel/irq.h>
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#include <kernel/panic.h>
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#include <xen/event_channel.h>
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#include <xen_hypercall-x86_32.h>
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#include <embox/unit.h>
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#include <math.h>
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#include <time.h>
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#include <xen/xen.h>
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extern shared_info_t xen_shared_info;
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static int integratorcp_clock_setup(struct clock_source *cs) {
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	return 0;
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}
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static struct time_event_device xen_event_device = {
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	.name = "xen event device",
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	.set_periodic = integratorcp_clock_setup,
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	.irq_nr = -1
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};
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static cycle_t xen_tcd_read(struct clock_source *cs) {
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	return 0;
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}
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static struct time_counter_device xen_tcd = {
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	.cycle_hz = 1000,
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	.read = xen_tcd_read,
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};
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static uint64_t system_time;
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static uint64_t xen_time(void) {
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	return xen_shared_info.vcpu_info[0].time.system_time;
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}
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static irq_return_t clock_handler(unsigned int irq_nr, void *dev_id) {
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	uint64_t time = xen_time();
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	const int n = (time - system_time) / NSEC_PER_MSEC;
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	for (int i = 0; i < n; i++) {
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		clock_tick_handler(dev_id);
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	}
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	return IRQ_HANDLED;
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}
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static int xen_clock_init(struct clock_source *cs) {
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	evtchn_bind_virq_t op;
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	op.virq = VIRQ_TIMER;
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	op.vcpu = 0;
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	if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq, &op) != 0) {
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		panic("Error has happened during timer initialization.\n");
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	}
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	xen_event_device.irq_nr = op.port;
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	system_time = xen_time();
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	return irq_attach(op.port, clock_handler, 0, cs, "xen clock irq");
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}
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CLOCK_SOURCE_DEF(xen,  xen_clock_init, NULL,
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	&xen_event_device, &xen_tcd);
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