xref: /openbmc/u-boot/arch/m68k/lib/time.c (revision 26749582)
1 /*
2  * (C) Copyright 2003 Josef Baumgartner <josef.baumgartner@telex.de>
3  *
4  * (C) Copyright 2000
5  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
6  *
7  * See file CREDITS for list of people who contributed to this
8  * project.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License as
12  * published by the Free Software Foundation; either version 2 of
13  * the License, or (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
23  * MA 02111-1307 USA
24  */
25 
26 #include <common.h>
27 
28 #include <asm/timer.h>
29 #include <asm/immap.h>
30 #include <watchdog.h>
31 
32 DECLARE_GLOBAL_DATA_PTR;
33 
34 static volatile ulong timestamp = 0;
35 
36 #ifndef CONFIG_SYS_WATCHDOG_FREQ
37 #define CONFIG_SYS_WATCHDOG_FREQ (CONFIG_SYS_HZ / 2)
38 #endif
39 
40 #if defined(CONFIG_MCFTMR)
41 #ifndef CONFIG_SYS_UDELAY_BASE
42 #	error	"uDelay base not defined!"
43 #endif
44 
45 #if !defined(CONFIG_SYS_TMR_BASE) || !defined(CONFIG_SYS_INTR_BASE) || !defined(CONFIG_SYS_TMRINTR_NO) || !defined(CONFIG_SYS_TMRINTR_MASK)
46 #	error	"TMR_BASE, INTR_BASE, TMRINTR_NO or TMRINTR_MASk not defined!"
47 #endif
48 extern void dtimer_intr_setup(void);
49 
50 void __udelay(unsigned long usec)
51 {
52 	volatile dtmr_t *timerp = (dtmr_t *) (CONFIG_SYS_UDELAY_BASE);
53 	uint start, now, tmp;
54 
55 	while (usec > 0) {
56 		if (usec > 65000)
57 			tmp = 65000;
58 		else
59 			tmp = usec;
60 		usec = usec - tmp;
61 
62 		/* Set up TIMER 3 as timebase clock */
63 		timerp->tmr = DTIM_DTMR_RST_RST;
64 		timerp->tcn = 0;
65 		/* set period to 1 us */
66 		timerp->tmr =
67 		    CONFIG_SYS_TIMER_PRESCALER | DTIM_DTMR_CLK_DIV1 | DTIM_DTMR_FRR |
68 		    DTIM_DTMR_RST_EN;
69 
70 		start = now = timerp->tcn;
71 		while (now < start + tmp)
72 			now = timerp->tcn;
73 	}
74 }
75 
76 void dtimer_interrupt(void *not_used)
77 {
78 	volatile dtmr_t *timerp = (dtmr_t *) (CONFIG_SYS_TMR_BASE);
79 
80 	/* check for timer interrupt asserted */
81 	if ((CONFIG_SYS_TMRPND_REG & CONFIG_SYS_TMRINTR_MASK) == CONFIG_SYS_TMRINTR_PEND) {
82 		timerp->ter = (DTIM_DTER_CAP | DTIM_DTER_REF);
83 		timestamp++;
84 
85 		#if defined(CONFIG_WATCHDOG) || defined (CONFIG_HW_WATCHDOG)
86 		if ((timestamp % (CONFIG_SYS_WATCHDOG_FREQ)) == 0) {
87 			WATCHDOG_RESET ();
88 		}
89 		#endif    /* CONFIG_WATCHDOG || CONFIG_HW_WATCHDOG */
90 		return;
91 	}
92 }
93 
94 void timer_init(void)
95 {
96 	volatile dtmr_t *timerp = (dtmr_t *) (CONFIG_SYS_TMR_BASE);
97 
98 	timestamp = 0;
99 
100 	timerp->tcn = 0;
101 	timerp->trr = 0;
102 
103 	/* Set up TIMER 4 as clock */
104 	timerp->tmr = DTIM_DTMR_RST_RST;
105 
106 	/* initialize and enable timer interrupt */
107 	irq_install_handler(CONFIG_SYS_TMRINTR_NO, dtimer_interrupt, 0);
108 
109 	timerp->tcn = 0;
110 	timerp->trr = 1000;	/* Interrupt every ms */
111 
112 	dtimer_intr_setup();
113 
114 	/* set a period of 1us, set timer mode to restart and enable timer and interrupt */
115 	timerp->tmr = CONFIG_SYS_TIMER_PRESCALER | DTIM_DTMR_CLK_DIV1 |
116 	    DTIM_DTMR_FRR | DTIM_DTMR_ORRI | DTIM_DTMR_RST_EN;
117 }
118 
119 ulong get_timer(ulong base)
120 {
121 	return (timestamp - base);
122 }
123 
124 #endif				/* CONFIG_MCFTMR */
125 
126 #if defined(CONFIG_MCFPIT)
127 #if !defined(CONFIG_SYS_PIT_BASE)
128 #	error	"CONFIG_SYS_PIT_BASE not defined!"
129 #endif
130 
131 static unsigned short lastinc;
132 
133 void __udelay(unsigned long usec)
134 {
135 	volatile pit_t *timerp = (pit_t *) (CONFIG_SYS_UDELAY_BASE);
136 	uint tmp;
137 
138 	while (usec > 0) {
139 		if (usec > 65000)
140 			tmp = 65000;
141 		else
142 			tmp = usec;
143 		usec = usec - tmp;
144 
145 		/* Set up TIMER 3 as timebase clock */
146 		timerp->pcsr = PIT_PCSR_OVW;
147 		timerp->pmr = 0;
148 		/* set period to 1 us */
149 		timerp->pcsr |= PIT_PCSR_PRE(CONFIG_SYS_PIT_PRESCALE) | PIT_PCSR_EN;
150 
151 		timerp->pmr = tmp;
152 		while (timerp->pcntr > 0) ;
153 	}
154 }
155 
156 void timer_init(void)
157 {
158 	volatile pit_t *timerp = (pit_t *) (CONFIG_SYS_PIT_BASE);
159 	timestamp = 0;
160 
161 	/* Set up TIMER 4 as poll clock */
162 	timerp->pcsr = PIT_PCSR_OVW;
163 	timerp->pmr = lastinc = 0;
164 	timerp->pcsr |= PIT_PCSR_PRE(CONFIG_SYS_PIT_PRESCALE) | PIT_PCSR_EN;
165 }
166 
167 ulong get_timer(ulong base)
168 {
169 	unsigned short now, diff;
170 	volatile pit_t *timerp = (pit_t *) (CONFIG_SYS_PIT_BASE);
171 
172 	now = timerp->pcntr;
173 	diff = -(now - lastinc);
174 
175 	timestamp += diff;
176 	lastinc = now;
177 	return timestamp - base;
178 }
179 
180 void wait_ticks(unsigned long ticks)
181 {
182 	u32 start = get_timer(0);
183 	while (get_timer(start) < ticks) ;
184 }
185 #endif				/* CONFIG_MCFPIT */
186 
187 /*
188  * This function is derived from PowerPC code (read timebase as long long).
189  * On M68K it just returns the timer value.
190  */
191 unsigned long long get_ticks(void)
192 {
193 	return get_timer(0);
194 }
195 
196 unsigned long usec2ticks(unsigned long usec)
197 {
198 	return get_timer(usec);
199 }
200 
201 /*
202  * This function is derived from PowerPC code (timebase clock frequency).
203  * On M68K it returns the number of timer ticks per second.
204  */
205 ulong get_tbclk(void)
206 {
207 	ulong tbclk;
208 	tbclk = CONFIG_SYS_HZ;
209 	return tbclk;
210 }
211