1 /*
2 * Copyright (C) 2011-2012 Texas Instruments Incorporated
3 *
4 * This borrows heavily from powerpc version, which is:
5 *
6 * Derived from arch/i386/kernel/irq.c
7 * Copyright (C) 1992 Linus Torvalds
8 * Adapted from arch/i386 by Gary Thomas
9 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
10 * Updated and modified by Cort Dougan <cort@fsmlabs.com>
11 * Copyright (C) 1996-2001 Cort Dougan
12 * Adapted for Power Macintosh by Paul Mackerras
13 * Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
14 *
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License
17 * as published by the Free Software Foundation; either version
18 * 2 of the License, or (at your option) any later version.
19 */
20 #include <linux/slab.h>
21 #include <linux/seq_file.h>
22 #include <linux/radix-tree.h>
23 #include <linux/module.h>
24 #include <linux/of.h>
25 #include <linux/of_irq.h>
26 #include <linux/interrupt.h>
27 #include <linux/kernel_stat.h>
28
29 #include <asm/megamod-pic.h>
30 #include <asm/special_insns.h>
31
32 unsigned long irq_err_count;
33
34 static DEFINE_RAW_SPINLOCK(core_irq_lock);
35
mask_core_irq(struct irq_data * data)36 static void mask_core_irq(struct irq_data *data)
37 {
38 unsigned int prio = data->hwirq;
39
40 raw_spin_lock(&core_irq_lock);
41 and_creg(IER, ~(1 << prio));
42 raw_spin_unlock(&core_irq_lock);
43 }
44
unmask_core_irq(struct irq_data * data)45 static void unmask_core_irq(struct irq_data *data)
46 {
47 unsigned int prio = data->hwirq;
48
49 raw_spin_lock(&core_irq_lock);
50 or_creg(IER, 1 << prio);
51 raw_spin_unlock(&core_irq_lock);
52 }
53
54 static struct irq_chip core_chip = {
55 .name = "core",
56 .irq_mask = mask_core_irq,
57 .irq_unmask = unmask_core_irq,
58 };
59
60 static int prio_to_virq[NR_PRIORITY_IRQS];
61
c6x_do_IRQ(unsigned int prio,struct pt_regs * regs)62 asmlinkage void c6x_do_IRQ(unsigned int prio, struct pt_regs *regs)
63 {
64 struct pt_regs *old_regs = set_irq_regs(regs);
65
66 irq_enter();
67
68 generic_handle_irq(prio_to_virq[prio]);
69
70 irq_exit();
71
72 set_irq_regs(old_regs);
73 }
74
75 static struct irq_domain *core_domain;
76
core_domain_map(struct irq_domain * h,unsigned int virq,irq_hw_number_t hw)77 static int core_domain_map(struct irq_domain *h, unsigned int virq,
78 irq_hw_number_t hw)
79 {
80 if (hw < 4 || hw >= NR_PRIORITY_IRQS)
81 return -EINVAL;
82
83 prio_to_virq[hw] = virq;
84
85 irq_set_status_flags(virq, IRQ_LEVEL);
86 irq_set_chip_and_handler(virq, &core_chip, handle_level_irq);
87 return 0;
88 }
89
90 static const struct irq_domain_ops core_domain_ops = {
91 .map = core_domain_map,
92 .xlate = irq_domain_xlate_onecell,
93 };
94
init_IRQ(void)95 void __init init_IRQ(void)
96 {
97 struct device_node *np;
98
99 /* Mask all priority IRQs */
100 and_creg(IER, ~0xfff0);
101
102 np = of_find_compatible_node(NULL, NULL, "ti,c64x+core-pic");
103 if (np != NULL) {
104 /* create the core host */
105 core_domain = irq_domain_add_linear(np, NR_PRIORITY_IRQS,
106 &core_domain_ops, NULL);
107 if (core_domain)
108 irq_set_default_host(core_domain);
109 of_node_put(np);
110 }
111
112 printk(KERN_INFO "Core interrupt controller initialized\n");
113
114 /* now we're ready for other SoC controllers */
115 megamod_pic_init();
116
117 /* Clear all general IRQ flags */
118 set_creg(ICR, 0xfff0);
119 }
120
ack_bad_irq(int irq)121 void ack_bad_irq(int irq)
122 {
123 printk(KERN_ERR "IRQ: spurious interrupt %d\n", irq);
124 irq_err_count++;
125 }
126
arch_show_interrupts(struct seq_file * p,int prec)127 int arch_show_interrupts(struct seq_file *p, int prec)
128 {
129 seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count);
130 return 0;
131 }
132