xref: /openbmc/u-boot/arch/m68k/lib/interrupts.c (revision 57efeb04)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2000-2004
4  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5  *
6  * (C) Copyright 2007 Freescale Semiconductor Inc
7  * TsiChung Liew (Tsi-Chung.Liew@freescale.com)
8  */
9 
10 #include <common.h>
11 #include <watchdog.h>
12 #include <asm/processor.h>
13 #include <asm/immap.h>
14 
15 #define	NR_IRQS		(CONFIG_SYS_NUM_IRQS)
16 
17 /*
18  * Interrupt vector functions.
19  */
20 struct interrupt_action {
21 	interrupt_handler_t *handler;
22 	void *arg;
23 };
24 
25 static struct interrupt_action irq_vecs[NR_IRQS];
26 
27 static __inline__ unsigned short get_sr (void)
28 {
29 	unsigned short sr;
30 
31 	asm volatile ("move.w %%sr,%0":"=r" (sr):);
32 
33 	return sr;
34 }
35 
36 static __inline__ void set_sr (unsigned short sr)
37 {
38 	asm volatile ("move.w %0,%%sr"::"r" (sr));
39 }
40 
41 /************************************************************************/
42 /*
43  * Install and free an interrupt handler
44  */
45 void irq_install_handler (int vec, interrupt_handler_t * handler, void *arg)
46 {
47 	if ((vec < 0) || (vec >= NR_IRQS)) {
48 		printf ("irq_install_handler: wrong interrupt vector %d\n",
49 			vec);
50 		return;
51 	}
52 
53 	irq_vecs[vec].handler = handler;
54 	irq_vecs[vec].arg = arg;
55 }
56 
57 void irq_free_handler (int vec)
58 {
59 	if ((vec < 0) || (vec >= NR_IRQS)) {
60 		return;
61 	}
62 
63 	irq_vecs[vec].handler = NULL;
64 	irq_vecs[vec].arg = NULL;
65 }
66 
67 void enable_interrupts (void)
68 {
69 	unsigned short sr;
70 
71 	sr = get_sr ();
72 	set_sr (sr & ~0x0700);
73 }
74 
75 int disable_interrupts (void)
76 {
77 	unsigned short sr;
78 
79 	sr = get_sr ();
80 	set_sr (sr | 0x0700);
81 
82 	return ((sr & 0x0700) == 0);	/* return true, if interrupts were enabled before */
83 }
84 
85 void int_handler (struct pt_regs *fp)
86 {
87 	int vec;
88 
89 	vec = (fp->vector >> 2) & 0xff;
90 	if (vec > 0x40)
91 		vec -= 0x40;
92 
93 	if (irq_vecs[vec].handler != NULL) {
94 		irq_vecs[vec].handler (irq_vecs[vec].arg);
95 	} else {
96 		printf ("\nBogus External Interrupt Vector %d\n", vec);
97 	}
98 }
99