blob: 07e132ad2f7d957fc2230d7c850fdfb4030ad87a [file] [log] [blame]
Ilya Yanok416a41f2009-06-08 04:12:45 +04001/*
2 * (C) Copyright 2002
3 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
4 * Marius Groeger <mgroeger@sysgo.de>
5 *
6 * (C) Copyright 2002
7 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
8 * Alex Zuepke <azu@sysgo.de>
9 *
10 * (C) Copyright 2002
11 * Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
12 *
13 * (C) Copyright 2009
14 * Ilya Yanok, Emcraft Systems Ltd, <yanok@emcraft.com>
15 *
16 * See file CREDITS for list of people who contributed to this
17 * project.
18 *
19 * This program is free software; you can redistribute it and/or
20 * modify it under the terms of the GNU General Public License as
21 * published by the Free Software Foundation; either version 2 of
22 * the License, or (at your option) any later version.
23 *
24 * This program is distributed in the hope that it will be useful,
25 * but WITHOUT ANY WARRANTY; without even the implied warranty of
26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
27 * GNU General Public License for more details.
28 *
29 * You should have received a copy of the GNU General Public License
30 * along with this program; if not, write to the Free Software
31 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
32 * MA 02111-1307 USA
33 */
34
35#include <common.h>
36#include <div64.h>
37#include <asm/io.h>
38#include <asm/arch/imx-regs.h>
39
40/* General purpose timers bitfields */
41#define GPTCR_SWR (1 << 15) /* Software reset */
42#define GPTCR_FRR (1 << 8) /* Freerun / restart */
43#define GPTCR_CLKSOURCE_32 (4 << 1) /* Clock source */
44#define GPTCR_TEN 1 /* Timer enable */
45
Heiko Schocher5504dab2011-01-20 22:56:39 +000046DECLARE_GLOBAL_DATA_PTR;
47
Simon Glass2655ee12012-12-13 20:48:34 +000048#define timestamp (gd->arch.tbl)
Simon Glassa848da52012-12-13 20:48:35 +000049#define lastinc (gd->arch.lastinc)
Ilya Yanok416a41f2009-06-08 04:12:45 +040050
51/*
52 * "time" is measured in 1 / CONFIG_SYS_HZ seconds,
53 * "tick" is internal timer period
54 */
55#ifdef CONFIG_MX27_TIMER_HIGH_PRECISION
56/* ~0.4% error - measured with stop-watch on 100s boot-delay */
57static inline unsigned long long tick_to_time(unsigned long long tick)
58{
59 tick *= CONFIG_SYS_HZ;
60 do_div(tick, CONFIG_MX27_CLK32);
61 return tick;
62}
63
64static inline unsigned long long time_to_tick(unsigned long long time)
65{
66 time *= CONFIG_MX27_CLK32;
67 do_div(time, CONFIG_SYS_HZ);
68 return time;
69}
70
71static inline unsigned long long us_to_tick(unsigned long long us)
72{
73 us = us * CONFIG_MX27_CLK32 + 999999;
74 do_div(us, 1000000);
75 return us;
76}
77#else
78/* ~2% error */
79#define TICK_PER_TIME ((CONFIG_MX27_CLK32 + CONFIG_SYS_HZ / 2) / \
80 CONFIG_SYS_HZ)
81#define US_PER_TICK (1000000 / CONFIG_MX27_CLK32)
82
83static inline unsigned long long tick_to_time(unsigned long long tick)
84{
85 do_div(tick, TICK_PER_TIME);
86 return tick;
87}
88
89static inline unsigned long long time_to_tick(unsigned long long time)
90{
91 return time * TICK_PER_TIME;
92}
93
94static inline unsigned long long us_to_tick(unsigned long long us)
95{
96 us += US_PER_TICK - 1;
97 do_div(us, US_PER_TICK);
98 return us;
99}
100#endif
101
102/* nothing really to do with interrupts, just starts up a counter. */
103/* The 32768Hz 32-bit timer overruns in 131072 seconds */
104int timer_init(void)
105{
106 int i;
107 struct gpt_regs *regs = (struct gpt_regs *)IMX_TIM1_BASE;
108 struct pll_regs *pll = (struct pll_regs *)IMX_PLL_BASE;
109
110 /* setup GP Timer 1 */
111 writel(GPTCR_SWR, &regs->gpt_tctl);
112
113 writel(readl(&pll->pccr0) | PCCR0_GPT1_EN, &pll->pccr0);
114 writel(readl(&pll->pccr1) | PCCR1_PERCLK1_EN, &pll->pccr1);
115
116 for (i = 0; i < 100; i++)
117 writel(0, &regs->gpt_tctl); /* We have no udelay by now */
118 writel(0, &regs->gpt_tprer); /* 32Khz */
119 /* Freerun Mode, PERCLK1 input */
120 writel(readl(&regs->gpt_tctl) | GPTCR_CLKSOURCE_32 | GPTCR_FRR,
121 &regs->gpt_tctl);
122 writel(readl(&regs->gpt_tctl) | GPTCR_TEN, &regs->gpt_tctl);
123
124 return 0;
125}
126
Fabio Estevamf231efb2011-10-13 05:34:59 +0000127unsigned long long get_ticks(void)
Ilya Yanok416a41f2009-06-08 04:12:45 +0400128{
129 struct gpt_regs *regs = (struct gpt_regs *)IMX_TIM1_BASE;
130 ulong now = readl(&regs->gpt_tcn); /* current tick value */
131
132 if (now >= lastinc) {
133 /*
134 * normal mode (non roll)
135 * move stamp forward with absolut diff ticks
136 */
137 timestamp += (now - lastinc);
138 } else {
139 /* we have rollover of incrementer */
140 timestamp += (0xFFFFFFFF - lastinc) + now;
141 }
142 lastinc = now;
143 return timestamp;
144}
145
Fabio Estevamf231efb2011-10-13 05:34:59 +0000146ulong get_timer_masked(void)
Ilya Yanok416a41f2009-06-08 04:12:45 +0400147{
148 /*
149 * get_ticks() returns a long long (64 bit), it wraps in
150 * 2^64 / CONFIG_MX27_CLK32 = 2^64 / 2^15 = 2^49 ~ 5 * 10^14 (s) ~
151 * 5 * 10^9 days... and get_ticks() * CONFIG_SYS_HZ wraps in
152 * 5 * 10^6 days - long enough.
153 */
154 return tick_to_time(get_ticks());
155}
156
Fabio Estevamf231efb2011-10-13 05:34:59 +0000157ulong get_timer(ulong base)
Ilya Yanok416a41f2009-06-08 04:12:45 +0400158{
Fabio Estevamf231efb2011-10-13 05:34:59 +0000159 return get_timer_masked() - base;
Ilya Yanok416a41f2009-06-08 04:12:45 +0400160}
161
Wolfgang Denk1d695be2009-07-07 22:35:02 +0200162/* delay x useconds AND preserve advance timstamp value */
Fabio Estevamf231efb2011-10-13 05:34:59 +0000163void __udelay(unsigned long usec)
Ilya Yanok416a41f2009-06-08 04:12:45 +0400164{
165 unsigned long long tmp;
166 ulong tmo;
167
168 tmo = us_to_tick(usec);
169 tmp = get_ticks() + tmo; /* get current timestamp */
170
171 while (get_ticks() < tmp) /* loop till event */
172 /*NOP*/;
173}
Stefano Babic51db3562012-02-07 18:32:56 +0100174
175ulong get_tbclk(void)
176{
177 return CONFIG_MX27_CLK32;
178}