xref: /openbmc/u-boot/arch/microblaze/cpu/timer.c (revision 93082044)
1 /*
2  * (C) Copyright 2007 Michal Simek
3  *
4  * Michal  SIMEK <monstr@monstr.eu>
5  *
6  * See file CREDITS for list of people who contributed to this
7  * project.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License as
11  * published by the Free Software Foundation; either version 2 of
12  * the License, or (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
22  * MA 02111-1307 USA
23  */
24 
25 #include <common.h>
26 #include <asm/microblaze_timer.h>
27 #include <asm/microblaze_intc.h>
28 
29 volatile int timestamp = 0;
30 
31 #ifdef CONFIG_SYS_TIMER_0
32 ulong get_timer (ulong base)
33 {
34 	return (timestamp - base);
35 }
36 #else
37 ulong get_timer (ulong base)
38 {
39 	return (timestamp++ - base);
40 }
41 #endif
42 
43 #ifdef CONFIG_SYS_INTC_0
44 #ifdef CONFIG_SYS_TIMER_0
45 microblaze_timer_t *tmr = (microblaze_timer_t *) (CONFIG_SYS_TIMER_0_ADDR);
46 
47 void timer_isr (void *arg)
48 {
49 	timestamp++;
50 	tmr->control = tmr->control | TIMER_INTERRUPT;
51 }
52 
53 int timer_init (void)
54 {
55 	tmr->loadreg = CONFIG_SYS_TIMER_0_PRELOAD;
56 	tmr->control = TIMER_INTERRUPT | TIMER_RESET;
57 	tmr->control =
58 	    TIMER_ENABLE | TIMER_ENABLE_INTR | TIMER_RELOAD | TIMER_DOWN_COUNT;
59 	timestamp = 0;
60 	install_interrupt_handler (CONFIG_SYS_TIMER_0_IRQ, timer_isr, (void *)tmr);
61 	return 0;
62 }
63 #endif
64 #endif
65 
66 /*
67  * This function is derived from PowerPC code (read timebase as long long).
68  * On Microblaze it just returns the timer value.
69  */
70 unsigned long long get_ticks(void)
71 {
72 	return get_timer(0);
73 }
74 
75 /*
76  * This function is derived from PowerPC code (timebase clock frequency).
77  * On Microblaze it returns the number of timer ticks per second.
78  */
79 ulong get_tbclk(void)
80 {
81 	return CONFIG_SYS_HZ;
82 }
83