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(lock: &srm_irq_lock);
25 cserve_ena(d->irq - 16);
26 spin_unlock(lock: &srm_irq_lock);
27}
28
29static void
30srm_disable_irq(struct irq_data *d)
31{
32 spin_lock(lock: &srm_irq_lock);
33 cserve_dis(d->irq - 16);
34 spin_unlock(lock: &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(irq: i, chip: &srm_irq_type, handle: handle_level_irq);
56 irq_set_status_flags(irq: i, set: 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

source code of linux/arch/alpha/kernel/irq_srm.c