1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Author: Kumar Gala <galak@kernel.crashing.org>
4 *
5 * Copyright 2009 Freescale Semiconductor Inc.
6 */
7
8#include <linux/stddef.h>
9#include <linux/kernel.h>
10#include <linux/smp.h>
11#include <linux/threads.h>
12#include <linux/hardirq.h>
13
14#include <asm/dbell.h>
15#include <asm/irq_regs.h>
16#include <asm/kvm_ppc.h>
17#include <asm/trace.h>
18
19#ifdef CONFIG_SMP
20
21void doorbell_exception(struct pt_regs *regs)
22{
23	struct pt_regs *old_regs = set_irq_regs(regs);
24
25	irq_enter();
26	trace_doorbell_entry(regs);
27
28	ppc_msgsync();
29
30	may_hard_irq_enable();
31
32	kvmppc_clear_host_ipi(smp_processor_id());
33	__this_cpu_inc(irq_stat.doorbell_irqs);
34
35	smp_ipi_demux_relaxed(); /* already performed the barrier */
36
37	trace_doorbell_exit(regs);
38	irq_exit();
39	set_irq_regs(old_regs);
40}
41#else /* CONFIG_SMP */
42void doorbell_exception(struct pt_regs *regs)
43{
44	printk(KERN_WARNING "Received doorbell on non-smp system\n");
45}
46#endif /* CONFIG_SMP */
47
48