1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * (C) Copyright 2000-2002
4 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 *
6 * (C) Copyright 2004, Psyent Corporation <www.psyent.com>
7 * Scott McNutt <smcnutt@psyent.com>
8 */
9
10 #include <command.h>
11 #include <irq_func.h>
12 #include <asm/nios2.h>
13 #include <asm/types.h>
14 #include <asm/io.h>
15 #include <asm/ptrace.h>
16
17 /*************************************************************************/
18 struct irq_action {
19 interrupt_handler_t *handler;
20 void *arg;
21 int count;
22 };
23
24 static struct irq_action vecs[32];
25
disable_interrupts(void)26 int disable_interrupts(void)
27 {
28 int val = rdctl (CTL_STATUS);
29 wrctl (CTL_STATUS, val & ~STATUS_IE);
30 return (val & STATUS_IE);
31 }
32
enable_interrupts(void)33 void enable_interrupts( void )
34 {
35 int val = rdctl (CTL_STATUS);
36 wrctl (CTL_STATUS, val | STATUS_IE);
37 }
38
external_interrupt(struct pt_regs * regs)39 void external_interrupt(struct pt_regs *regs)
40 {
41 unsigned irqs;
42 struct irq_action *act;
43
44 /* Evaluate only irqs that are both enabled AND pending */
45 irqs = rdctl (CTL_IENABLE) & rdctl (CTL_IPENDING);
46 act = vecs;
47
48 /* Assume (as does the Nios2 HAL) that bit 0 is highest
49 * priority. NOTE: There is ALWAYS a handler assigned
50 * (the default if no other).
51 */
52 while (irqs) {
53 if (irqs & 1) {
54 act->handler (act->arg);
55 act->count++;
56 }
57 irqs >>=1;
58 act++;
59 }
60 }
61
def_hdlr(void * arg)62 static void def_hdlr (void *arg)
63 {
64 unsigned irqs = rdctl (CTL_IENABLE);
65
66 /* Disable the individual interrupt -- with gratuitous
67 * warning.
68 */
69 irqs &= ~(1 << (int)arg);
70 wrctl (CTL_IENABLE, irqs);
71 printf ("WARNING: Disabling unhandled interrupt: %d\n",
72 (int)arg);
73 }
74
75 /*************************************************************************/
irq_install_handler(int irq,interrupt_handler_t * hdlr,void * arg)76 void irq_install_handler(int irq, interrupt_handler_t *hdlr, void *arg)
77 {
78
79 int flag;
80 struct irq_action *act;
81 unsigned ena = rdctl (CTL_IENABLE);
82
83 if ((irq < 0) || (irq > 31))
84 return;
85 act = &vecs[irq];
86
87 flag = disable_interrupts();
88 if (hdlr) {
89 act->handler = hdlr;
90 act->arg = arg;
91 ena |= (1 << irq); /* enable */
92 } else {
93 act->handler = def_hdlr;
94 act->arg = (void *)irq;
95 ena &= ~(1 << irq); /* disable */
96 }
97 wrctl (CTL_IENABLE, ena);
98 if (flag) enable_interrupts();
99 }
100
interrupt_init(void)101 int interrupt_init(void)
102 {
103 int i;
104
105 /* Assign the default handler to all */
106 for (i = 0; i < 32; i++) {
107 vecs[i].handler = def_hdlr;
108 vecs[i].arg = (void *)i;
109 vecs[i].count = 0;
110 }
111
112 enable_interrupts();
113 return (0);
114 }
115
116 /*************************************************************************/
117 #if defined(CONFIG_CMD_IRQ)
do_irqinfo(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])118 int do_irqinfo(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
119 {
120 int i;
121 struct irq_action *act = vecs;
122
123 printf ("\nInterrupt-Information:\n\n");
124 printf ("Nr Routine Arg Count\n");
125 printf ("-----------------------------\n");
126
127 for (i=0; i<32; i++) {
128 if (act->handler != def_hdlr) {
129 printf ("%02d %08lx %08lx %d\n",
130 i,
131 (ulong)act->handler,
132 (ulong)act->arg,
133 act->count);
134 }
135 act++;
136 }
137 printf ("\n");
138
139 return (0);
140 }
141 #endif
142