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/* -*- Mode:C; c-basic-offset:4; tab-width:4 -*-
****************************************************************************
* (C) 2003 - Rolf Neugebauer - Intel Research Cambridge
* (C) 2005 - Grzegorz Milos - Intel Research Cambridge
****************************************************************************
*
* File: events.c
* Author: Rolf Neugebauer (neugebar@dcs.gla.ac.uk)
* Changes: Grzegorz Milos (gm281@cam.ac.uk)
*
* Date: Jul 2003, changes Jun 2005
*
* Environment: Xen Minimal OS
* Description: Deals with events recieved on event channels
*
****************************************************************************
*/
#include <os.h>
#include <mm.h>
#include <hypervisor.h>
#include <events.h>
#include <lib.h>
static ev_action_t ev_actions[NR_EVS];
void default_handler(int port, struct pt_regs *regs);
/*
* Demux events to different handlers.
*/
int do_event(u32 port, struct pt_regs *regs)
{
ev_action_t *action;
if (port >= NR_EVS) {
printk("Port number too large: %d\n", port);
return 0;
}
action = &ev_actions[port];
action->count++;
if (!action->handler)
goto out;
if (action->status & EVS_DISABLED)
goto out;
/* call the handler */
action->handler(port, regs);
clear_evtchn(port);
out:
return 1;
}
int bind_evtchn( u32 port, void (*handler)(int, struct pt_regs *) )
{
if(ev_actions[port].handler != default_handler)
printk("WARN: Handler for port %d already registered, replacing\n",
port);
ev_actions[port].handler = handler;
ev_actions[port].status &= ~EVS_DISABLED;
/* Finally unmask the port */
unmask_evtchn(port);
return port;
}
void unbind_evtchn( u32 port )
{
if (ev_actions[port].handler == default_handler)
printk("WARN: No handler for port %d when unbinding\n", port);
ev_actions[port].handler = default_handler;
ev_actions[port].status |= EVS_DISABLED;
}
int bind_virq( u32 virq, void (*handler)(int, struct pt_regs *) )
{
evtchn_op_t op;
int ret = 0;
/* Try to bind the virq to a port */
op.cmd = EVTCHNOP_bind_virq;
op.u.bind_virq.virq = virq;
op.u.bind_virq.vcpu = smp_processor_id();
if ( HYPERVISOR_event_channel_op(&op) != 0 )
{
ret = 1;
printk("Failed to bind virtual IRQ %d\n", virq);
goto out;
}
bind_evtchn(op.u.bind_virq.port, handler);
out:
return ret;
}
void unbind_virq( u32 port )
{
unbind_evtchn(port);
}
#if defined(__x86_64__)
/* Allocate 4 pages for the irqstack */
#define STACK_PAGES 4
char irqstack[1024 * 4 * STACK_PAGES];
static struct pda
{
int irqcount; /* offset 0 (used in x86_64.S) */
char *irqstackptr; /* 8 */
} cpu0_pda;
#endif
/*
* Initially all events are without a handler and disabled
*/
void init_events(void)
{
int i;
#if defined(__x86_64__)
asm volatile("movl %0,%%fs ; movl %0,%%gs" :: "r" (0));
wrmsrl(0xc0000101, &cpu0_pda); /* 0xc0000101 is MSR_GS_BASE */
cpu0_pda.irqcount = -1;
cpu0_pda.irqstackptr = irqstack + 1024 * 4 * STACK_PAGES;
#endif
/* inintialise event handler */
for ( i = 0; i < NR_EVS; i++ )
{
ev_actions[i].status = EVS_DISABLED;
ev_actions[i].handler = default_handler;
}
}
void default_handler(int port, struct pt_regs *regs) {
printk("[Port %d] - event received\n", port);
}
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