xref: /openbmc/u-boot/arch/m68k/lib/interrupts.c (revision 274bced8)
1 /*
2  * (C) Copyright 2000-2004
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * (C) Copyright 2007 Freescale Semiconductor Inc
6  * TsiChung Liew (Tsi-Chung.Liew@freescale.com)
7  *
8  * SPDX-License-Identifier:	GPL-2.0+
9  */
10 
11 #include <common.h>
12 #include <watchdog.h>
13 #include <asm/processor.h>
14 #include <asm/immap.h>
15 
16 #define	NR_IRQS		(CONFIG_SYS_NUM_IRQS)
17 
18 /*
19  * Interrupt vector functions.
20  */
21 struct interrupt_action {
22 	interrupt_handler_t *handler;
23 	void *arg;
24 };
25 
26 static struct interrupt_action irq_vecs[NR_IRQS];
27 
28 static __inline__ unsigned short get_sr (void)
29 {
30 	unsigned short sr;
31 
32 	asm volatile ("move.w %%sr,%0":"=r" (sr):);
33 
34 	return sr;
35 }
36 
37 static __inline__ void set_sr (unsigned short sr)
38 {
39 	asm volatile ("move.w %0,%%sr"::"r" (sr));
40 }
41 
42 /************************************************************************/
43 /*
44  * Install and free an interrupt handler
45  */
46 void irq_install_handler (int vec, interrupt_handler_t * handler, void *arg)
47 {
48 	if ((vec < 0) || (vec >= NR_IRQS)) {
49 		printf ("irq_install_handler: wrong interrupt vector %d\n",
50 			vec);
51 		return;
52 	}
53 
54 	irq_vecs[vec].handler = handler;
55 	irq_vecs[vec].arg = arg;
56 }
57 
58 void irq_free_handler (int vec)
59 {
60 	if ((vec < 0) || (vec >= NR_IRQS)) {
61 		return;
62 	}
63 
64 	irq_vecs[vec].handler = NULL;
65 	irq_vecs[vec].arg = NULL;
66 }
67 
68 void enable_interrupts (void)
69 {
70 	unsigned short sr;
71 
72 	sr = get_sr ();
73 	set_sr (sr & ~0x0700);
74 }
75 
76 int disable_interrupts (void)
77 {
78 	unsigned short sr;
79 
80 	sr = get_sr ();
81 	set_sr (sr | 0x0700);
82 
83 	return ((sr & 0x0700) == 0);	/* return true, if interrupts were enabled before */
84 }
85 
86 void int_handler (struct pt_regs *fp)
87 {
88 	int vec;
89 
90 	vec = (fp->vector >> 2) & 0xff;
91 	if (vec > 0x40)
92 		vec -= 0x40;
93 
94 	if (irq_vecs[vec].handler != NULL) {
95 		irq_vecs[vec].handler (irq_vecs[vec].arg);
96 	} else {
97 		printf ("\nBogus External Interrupt Vector %d\n", vec);
98 	}
99 }
100