xref: /openbmc/u-boot/arch/powerpc/lib/interrupts.c (revision a22bbfda)
1 /*
2  * (C) Copyright 2000-2002
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * (C) Copyright 2003
6  * Gleb Natapov <gnatapov@mrv.com>
7  *
8  * SPDX-License-Identifier:	GPL-2.0+
9  */
10 
11 #include <common.h>
12 #include <asm/processor.h>
13 #include <watchdog.h>
14 #ifdef CONFIG_LED_STATUS
15 #include <status_led.h>
16 #endif
17 
18 #ifdef CONFIG_SHOW_ACTIVITY
19 void board_show_activity (ulong) __attribute__((weak, alias("__board_show_activity")));
20 
21 void __board_show_activity (ulong dummy)
22 {
23 	return;
24 }
25 #endif /* CONFIG_SHOW_ACTIVITY */
26 
27 #ifndef CONFIG_SYS_WATCHDOG_FREQ
28 #define CONFIG_SYS_WATCHDOG_FREQ (CONFIG_SYS_HZ / 2)
29 #endif
30 
31 static unsigned decrementer_count; /* count value for 1e6/HZ microseconds */
32 
33 static __inline__ unsigned long get_dec (void)
34 {
35 	unsigned long val;
36 
37 	asm volatile ("mfdec %0":"=r" (val):);
38 
39 	return val;
40 }
41 
42 
43 static __inline__ void set_dec (unsigned long val)
44 {
45 	if (val)
46 		asm volatile ("mtdec %0"::"r" (val));
47 }
48 
49 
50 void enable_interrupts (void)
51 {
52 	set_msr (get_msr () | MSR_EE);
53 }
54 
55 /* returns flag if MSR_EE was set before */
56 int disable_interrupts (void)
57 {
58 	ulong msr = get_msr ();
59 
60 	set_msr (msr & ~MSR_EE);
61 	return ((msr & MSR_EE) != 0);
62 }
63 
64 int interrupt_init (void)
65 {
66 	int ret;
67 
68 	/* call cpu specific function from $(CPU)/interrupts.c */
69 	ret = interrupt_init_cpu (&decrementer_count);
70 
71 	if (ret)
72 		return ret;
73 
74 	set_dec (decrementer_count);
75 
76 	set_msr (get_msr () | MSR_EE);
77 
78 	return (0);
79 }
80 
81 static volatile ulong timestamp = 0;
82 
83 void timer_interrupt (struct pt_regs *regs)
84 {
85 	/* call cpu specific function from $(CPU)/interrupts.c */
86 	timer_interrupt_cpu (regs);
87 
88 	/* Restore Decrementer Count */
89 	set_dec (decrementer_count);
90 
91 	timestamp++;
92 
93 #if defined(CONFIG_WATCHDOG) || defined (CONFIG_HW_WATCHDOG)
94 	if ((timestamp % (CONFIG_SYS_WATCHDOG_FREQ)) == 0)
95 		WATCHDOG_RESET ();
96 #endif    /* CONFIG_WATCHDOG || CONFIG_HW_WATCHDOG */
97 
98 #ifdef CONFIG_LED_STATUS
99 	status_led_tick (timestamp);
100 #endif /* CONFIG_LED_STATUS */
101 
102 #ifdef CONFIG_SHOW_ACTIVITY
103 	board_show_activity (timestamp);
104 #endif /* CONFIG_SHOW_ACTIVITY */
105 }
106 
107 ulong get_timer (ulong base)
108 {
109 	return (timestamp - base);
110 }
111