xref: /openbmc/u-boot/arch/powerpc/lib/interrupts.c (revision 12308b12)
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 2003
7  * Gleb Natapov <gnatapov@mrv.com>
8  */
9 
10 #include <common.h>
11 #include <asm/processor.h>
12 #include <watchdog.h>
13 #ifdef CONFIG_LED_STATUS
14 #include <status_led.h>
15 #endif
16 
17 #ifdef CONFIG_SHOW_ACTIVITY
18 void board_show_activity (ulong) __attribute__((weak, alias("__board_show_activity")));
19 
20 void __board_show_activity (ulong dummy)
21 {
22 	return;
23 }
24 #endif /* CONFIG_SHOW_ACTIVITY */
25 
26 #ifndef CONFIG_SYS_WATCHDOG_FREQ
27 #define CONFIG_SYS_WATCHDOG_FREQ (CONFIG_SYS_HZ / 2)
28 #endif
29 
30 static unsigned decrementer_count; /* count value for 1e6/HZ microseconds */
31 
32 static __inline__ unsigned long get_dec (void)
33 {
34 	unsigned long val;
35 
36 	asm volatile ("mfdec %0":"=r" (val):);
37 
38 	return val;
39 }
40 
41 
42 static __inline__ void set_dec (unsigned long val)
43 {
44 	if (val)
45 		asm volatile ("mtdec %0"::"r" (val));
46 }
47 
48 
49 void enable_interrupts (void)
50 {
51 	set_msr (get_msr () | MSR_EE);
52 }
53 
54 /* returns flag if MSR_EE was set before */
55 int disable_interrupts (void)
56 {
57 	ulong msr = get_msr ();
58 
59 	set_msr (msr & ~MSR_EE);
60 	return ((msr & MSR_EE) != 0);
61 }
62 
63 int interrupt_init (void)
64 {
65 	/* call cpu specific function from $(CPU)/interrupts.c */
66 	interrupt_init_cpu (&decrementer_count);
67 
68 	set_dec (decrementer_count);
69 
70 	set_msr (get_msr () | MSR_EE);
71 
72 	return (0);
73 }
74 
75 static volatile ulong timestamp = 0;
76 
77 void timer_interrupt (struct pt_regs *regs)
78 {
79 	/* call cpu specific function from $(CPU)/interrupts.c */
80 	timer_interrupt_cpu (regs);
81 
82 	/* Restore Decrementer Count */
83 	set_dec (decrementer_count);
84 
85 	timestamp++;
86 
87 #if defined(CONFIG_WATCHDOG) || defined (CONFIG_HW_WATCHDOG)
88 	if ((timestamp % (CONFIG_SYS_WATCHDOG_FREQ)) == 0)
89 		WATCHDOG_RESET ();
90 #endif    /* CONFIG_WATCHDOG || CONFIG_HW_WATCHDOG */
91 
92 #ifdef CONFIG_LED_STATUS
93 	status_led_tick (timestamp);
94 #endif /* CONFIG_LED_STATUS */
95 
96 #ifdef CONFIG_SHOW_ACTIVITY
97 	board_show_activity (timestamp);
98 #endif /* CONFIG_SHOW_ACTIVITY */
99 }
100 
101 ulong get_timer (ulong base)
102 {
103 	return (timestamp - base);
104 }
105