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Wolfgang Denk74f43042005-09-25 01:48:28 +02001/*
2 * (C) Copyright 2003
3 * Texas Instruments <www.ti.com>
4 *
5 * (C) Copyright 2002
6 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
7 * Marius Groeger <mgroeger@sysgo.de>
8 *
9 * (C) Copyright 2002
10 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
11 * Alex Zuepke <azu@sysgo.de>
12 *
13 * (C) Copyright 2002-2004
14 * Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
15 *
16 * (C) Copyright 2004
17 * Philippe Robin, ARM Ltd. <philippe.robin@arm.com>
18 *
19 * See file CREDITS for list of people who contributed to this
20 * project.
21 *
22 * This program is free software; you can redistribute it and/or
23 * modify it under the terms of the GNU General Public License as
24 * published by the Free Software Foundation; either version 2 of
25 * the License, or (at your option) any later version.
26 *
27 * This program is distributed in the hope that it will be useful,
28 * but WITHOUT ANY WARRANTY; without even the implied warranty of
29 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
30 * GNU General Public License for more details.
31 *
32 * You should have received a copy of the GNU General Public License
33 * along with this program; if not, write to the Free Software
34 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
35 * MA 02111-1307 USA
36 */
37
38#include <common.h>
39#include <arm946es.h>
Wolfgang Denk74f43042005-09-25 01:48:28 +020040
41#define TIMER_LOAD_VAL 0xffffffff
42extern void reset_cpu(ulong addr);
43
Wolfgang Denk74f43042005-09-25 01:48:28 +020044#ifdef CONFIG_INTEGRATOR
45 /* Timer functionality supplied by Integrator board (AP or CP) */
46#else
47
48static ulong timestamp;
49static ulong lastdec;
50
51/* nothing really to do with interrupts, just starts up a counter. */
52int interrupt_init (void)
53{
54 /* init the timestamp and lastdec value */
55 reset_timer_masked();
56
57 return (0);
58}
59
60/*
61 * timer without interrupts
62 */
63
64void reset_timer (void)
65{
66 reset_timer_masked ();
67}
68
69ulong get_timer (ulong base)
70{
71 return get_timer_masked () - base;
72}
73
74void set_timer (ulong t)
75{
76 timestamp = t;
77}
78
79/* delay x useconds AND perserve advance timstamp value */
80void udelay(unsigned long usec)
81{
82 udelay_masked(usec);
83}
84
85void reset_timer_masked (void)
86{
87 /* reset time */
88 lastdec = READ_TIMER; /* capure current decrementer value time */
89 timestamp = 0; /* start "advancing" time stamp from 0 */
90}
91
92ulong get_timer_raw (void)
93{
94 ulong now = READ_TIMER; /* current tick value */
95
96 if (lastdec >= now) { /* normal mode (non roll) */
97 /* normal mode */
98 timestamp += lastdec - now; /* move stamp fordward with absoulte diff ticks */
99 } else { /* we have overflow of the count down timer */
100 /* nts = ts + ld + (TLV - now)
101 * ts=old stamp, ld=time that passed before passing through -1
102 * (TLV-now) amount of time after passing though -1
103 * nts = new "advancing time stamp"...it could also roll and cause problems.
104 */
105 timestamp += lastdec + TIMER_LOAD_VAL - now;
106 }
107 lastdec = now;
108
109 return timestamp;
110}
111
112ulong get_timer_masked (void)
113{
114 return get_timer_raw() / TIMER_LOAD_VAL;
115}
116
117/* waits specified delay value and resets timestamp */
118void udelay_masked (unsigned long usec)
119{
120 ulong tmo;
121
122 if(usec >= 1000){ /* if "big" number, spread normalization to seconds */
123 tmo = usec / 1000; /* start to normalize for usec to ticks per sec */
124 tmo *= CFG_HZ_CLOCK; /* find number of "ticks" to wait to achieve target */
125 tmo /= 1000; /* finish normalize. */
126 }else{ /* else small number, don't kill it prior to HZ multiply */
127 tmo = usec * CFG_HZ_CLOCK;
128 tmo /= (1000*1000);
129 }
130
131 reset_timer_masked (); /* set "advancing" timestamp to 0, set lastdec vaule */
132
133 while (get_timer_raw () < tmo) /* wait for time stamp to overtake tick number.*/
134 /*NOP*/;
135}
136
137/*
138 * This function is derived from PowerPC code (read timebase as long long).
139 * On ARM it just returns the timer value.
140 */
141unsigned long long get_ticks(void)
142{
143 return get_timer(0);
144}
145
146/*
147 * This function is derived from PowerPC code (timebase clock frequency).
148 * On ARM it returns the number of timer ticks per second.
149 */
150ulong get_tbclk (void)
151{
152 ulong tbclk;
153
154 tbclk = CFG_HZ;
155 return tbclk;
156}
157
158#endif /* CONFIG_INTEGRATOR */