xref: /openbmc/linux/arch/hexagon/kernel/irq_cpu.c (revision 5a158981)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * First-level interrupt controller model for Hexagon.
4  *
5  * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
6  */
7 
8 #include <linux/interrupt.h>
9 #include <asm/irq.h>
10 #include <asm/hexagon_vm.h>
11 
12 static void mask_irq(struct irq_data *data)
13 {
14 	__vmintop_locdis((long) data->irq);
15 }
16 
17 static void mask_irq_num(unsigned int irq)
18 {
19 	__vmintop_locdis((long) irq);
20 }
21 
22 static void unmask_irq(struct irq_data *data)
23 {
24 	__vmintop_locen((long) data->irq);
25 }
26 
27 /*  This is actually all we need for handle_fasteoi_irq  */
28 static void eoi_irq(struct irq_data *data)
29 {
30 	__vmintop_globen((long) data->irq);
31 }
32 
33 /* Power mamangement wake call. We don't need this, however,
34  * if this is absent, then an -ENXIO error is returned to the
35  * msm_serial driver, and it fails to correctly initialize.
36  * This is a bug in the msm_serial driver, but, for now, we
37  * work around it here, by providing this bogus handler.
38  * XXX FIXME!!! remove this when msm_serial is fixed.
39  */
40 static int set_wake(struct irq_data *data, unsigned int on)
41 {
42 	return 0;
43 }
44 
45 static struct irq_chip hexagon_irq_chip = {
46 	.name		= "HEXAGON",
47 	.irq_mask	= mask_irq,
48 	.irq_unmask	= unmask_irq,
49 	.irq_set_wake	= set_wake,
50 	.irq_eoi	= eoi_irq
51 };
52 
53 /**
54  * The hexagon core comes with a first-level interrupt controller
55  * with 32 total possible interrupts.  When the core is embedded
56  * into different systems/platforms, it is typically wrapped by
57  * macro cells that provide one or more second-level interrupt
58  * controllers that are cascaded into one or more of the first-level
59  * interrupts handled here. The precise wiring of these other
60  * irqs varies from platform to platform, and are set up & configured
61  * in the platform-specific files.
62  *
63  * The first-level interrupt controller is wrapped by the VM, which
64  * virtualizes the interrupt controller for us.  It provides a very
65  * simple, fast & efficient API, and so the fasteoi handler is
66  * appropriate for this case.
67  */
68 void __init init_IRQ(void)
69 {
70 	int irq;
71 
72 	for (irq = 0; irq < HEXAGON_CPUINTS; irq++) {
73 		mask_irq_num(irq);
74 		irq_set_chip_and_handler(irq, &hexagon_irq_chip,
75 						 handle_fasteoi_irq);
76 	}
77 }
78