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 */
19 DEFINE_SPINLOCK(srm_irq_lock);
20
21 static inline void
srm_enable_irq(struct irq_data * d)22 srm_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
29 static void
srm_disable_irq(struct irq_data * d)30 srm_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. */
38 static 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
45 void __init
init_srm_irqs(long max,unsigned long ignore_mask)46 init_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
60 void
srm_device_interrupt(unsigned long vector)61 srm_device_interrupt(unsigned long vector)
62 {
63 int irq = (vector - 0x800) >> 4;
64 handle_irq(irq);
65 }
66