linux-sg2042/arch/powerpc/kernel/dbell.c

60 lines
1.3 KiB
C

/*
* Author: Kumar Gala <galak@kernel.crashing.org>
*
* Copyright 2009 Freescale Semiconductor Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <linux/stddef.h>
#include <linux/kernel.h>
#include <linux/smp.h>
#include <linux/threads.h>
#include <linux/hardirq.h>
#include <asm/dbell.h>
#include <asm/irq_regs.h>
#include <asm/kvm_ppc.h>
#ifdef CONFIG_SMP
void doorbell_setup_this_cpu(void)
{
unsigned long tag = mfspr(SPRN_DOORBELL_CPUTAG) & PPC_DBELL_TAG_MASK;
smp_muxed_ipi_set_data(smp_processor_id(), tag);
}
void doorbell_cause_ipi(int cpu, unsigned long data)
{
/* Order previous accesses vs. msgsnd, which is treated as a store */
mb();
ppc_msgsnd(PPC_DBELL_MSGTYPE, 0, data);
}
void doorbell_exception(struct pt_regs *regs)
{
struct pt_regs *old_regs = set_irq_regs(regs);
irq_enter();
may_hard_irq_enable();
kvmppc_set_host_ipi(smp_processor_id(), 0);
__this_cpu_inc(irq_stat.doorbell_irqs);
smp_ipi_demux();
irq_exit();
set_irq_regs(old_regs);
}
#else /* CONFIG_SMP */
void doorbell_exception(struct pt_regs *regs)
{
printk(KERN_WARNING "Received doorbell on non-smp system\n");
}
#endif /* CONFIG_SMP */