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

 
 1/*
 2 * Author: Kumar Gala <galak@kernel.crashing.org>
 3 *
 4 * Copyright 2009 Freescale Semiconductor Inc.
 5 *
 6 * This program is free software; you can redistribute  it and/or modify it
 7 * under  the terms of  the GNU General  Public License as published by the
 8 * Free Software Foundation;  either version 2 of the  License, or (at your
 9 * option) any later version.
10 */
11
12#include <linux/stddef.h>
13#include <linux/kernel.h>
14#include <linux/smp.h>
15#include <linux/threads.h>
16#include <linux/hardirq.h>
17
18#include <asm/dbell.h>
19#include <asm/irq_regs.h>
 
 
20
21#ifdef CONFIG_SMP
22void doorbell_setup_this_cpu(void)
23{
24	unsigned long tag = mfspr(SPRN_DOORBELL_CPUTAG) & PPC_DBELL_TAG_MASK;
25
26	smp_muxed_ipi_set_data(smp_processor_id(), tag);
27}
28
29void doorbell_cause_ipi(int cpu, unsigned long data)
30{
31	/* Order previous accesses vs. msgsnd, which is treated as a store */
32	mb();
33	ppc_msgsnd(PPC_DBELL_MSGTYPE, 0, data);
34}
35
36void doorbell_exception(struct pt_regs *regs)
37{
38	struct pt_regs *old_regs = set_irq_regs(regs);
39
40	irq_enter();
 
 
 
41
42	may_hard_irq_enable();
43
44	__get_cpu_var(irq_stat).doorbell_irqs++;
 
45
46	smp_ipi_demux();
47
 
48	irq_exit();
49	set_irq_regs(old_regs);
50}
51#else /* CONFIG_SMP */
52void doorbell_exception(struct pt_regs *regs)
53{
54	printk(KERN_WARNING "Received doorbell on non-smp system\n");
55}
56#endif /* CONFIG_SMP */
57