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/interrupt.h>
16#include <asm/irq_regs.h>
17#include <asm/kvm_ppc.h>
18#include <asm/trace.h>
19
20#ifdef CONFIG_SMP
 
 
 
21
22DEFINE_INTERRUPT_HANDLER_ASYNC(doorbell_exception)
 
 
 
23{
24	struct pt_regs *old_regs = set_irq_regs(regs);
 
 
 
25
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
 
39	set_irq_regs(old_regs);
40}
41#else /* CONFIG_SMP */
42DEFINE_INTERRUPT_HANDLER_ASYNC(doorbell_exception)
43{
44	printk(KERN_WARNING "Received doorbell on non-smp system\n");
45}
46#endif /* CONFIG_SMP */

 
 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#include <asm/kvm_ppc.h>
 
21
22#ifdef CONFIG_SMP
23void doorbell_setup_this_cpu(void)
24{
25	unsigned long tag = mfspr(SPRN_DOORBELL_CPUTAG) & PPC_DBELL_TAG_MASK;
26
27	smp_muxed_ipi_set_data(smp_processor_id(), tag);
28}
29
30void doorbell_cause_ipi(int cpu, unsigned long data)
31{
32	/* Order previous accesses vs. msgsnd, which is treated as a store */
33	mb();
34	ppc_msgsnd(PPC_DBELL_MSGTYPE, 0, data);
35}
36
37void doorbell_exception(struct pt_regs *regs)
38{
39	struct pt_regs *old_regs = set_irq_regs(regs);
40
41	irq_enter();
42
43	may_hard_irq_enable();
44
45	kvmppc_set_host_ipi(smp_processor_id(), 0);
46	__this_cpu_inc(irq_stat.doorbell_irqs);
47
48	smp_ipi_demux();
 
 
49
50	irq_exit();
51	set_irq_regs(old_regs);
52}
53#else /* CONFIG_SMP */
54void doorbell_exception(struct pt_regs *regs)
55{
56	printk(KERN_WARNING "Received doorbell on non-smp system\n");
57}
58#endif /* CONFIG_SMP */
59