1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Handle interrupts from the SRM, assuming no additional weirdness.
4 */
5
6#include <linux/init.h>
7#include <linux/sched.h>
8#include <linux/irq.h>
9
10#include "proto.h"
11#include "irq_impl.h"
12
13
14/*
15 * Is the palcode SMP safe? In other words: can we call cserve_ena/dis
16 * at the same time in multiple CPUs? To be safe I added a spinlock
17 * but it can be removed trivially if the palcode is robust against smp.
18 */
19DEFINE_SPINLOCK(srm_irq_lock);
20
21static inline void
22srm_enable_irq(struct irq_data *d)
23{
24	spin_lock(&srm_irq_lock);
25	cserve_ena(d->irq - 16);
26	spin_unlock(&srm_irq_lock);
27}
28
29static void
30srm_disable_irq(struct irq_data *d)
31{
32	spin_lock(&srm_irq_lock);
33	cserve_dis(d->irq - 16);
34	spin_unlock(&srm_irq_lock);
35}
36
37/* Handle interrupts from the SRM, assuming no additional weirdness.  */
38static struct irq_chip srm_irq_type = {
39	.name		= "SRM",
40	.irq_unmask	= srm_enable_irq,
41	.irq_mask	= srm_disable_irq,
42	.irq_mask_ack	= srm_disable_irq,
43};
44
45void __init
46init_srm_irqs(long max, unsigned long ignore_mask)
47{
48	long i;
49
50	if (NR_IRQS <= 16)
51		return;
52	for (i = 16; i < max; ++i) {
53		if (i < 64 && ((ignore_mask >> i) & 1))
54			continue;
55		irq_set_chip_and_handler(i, &srm_irq_type, handle_level_irq);
56		irq_set_status_flags(i, IRQ_LEVEL);
57	}
58}
59
60void
61srm_device_interrupt(unsigned long vector)
62{
63	int irq = (vector - 0x800) >> 4;
64	handle_irq(irq);
65}
66