2 * Marvell PXA2xx/3xx timer driver
4 * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
6 * See file CREDITS for list of people who contributed to this
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.
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.
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,
25 #include <asm/arch/pxa-regs.h>
30 DECLARE_GLOBAL_DATA_PTR;
32 #define TIMER_LOAD_VAL 0xffffffff
34 #define timestamp (gd->tbl)
35 #define lastinc (gd->lastinc)
37 #if defined(CONFIG_CPU_PXA27X) || defined(CONFIG_CPU_MONAHANS)
38 #define TIMER_FREQ_HZ 3250000
39 #elif defined(CONFIG_CPU_PXA25X)
40 #define TIMER_FREQ_HZ 3686400
42 #error "Timer frequency unknown - please config PXA CPU type"
45 static unsigned long long tick_to_time(unsigned long long tick)
47 return tick * CONFIG_SYS_HZ / TIMER_FREQ_HZ;
50 static unsigned long long us_to_tick(unsigned long long us)
52 return (us * TIMER_FREQ_HZ) / 1000000;
61 unsigned long long get_ticks(void)
63 /* Current tick value */
64 uint32_t now = readl(OSCR);
68 * Normal mode (non roll)
69 * Move stamp forward with absolute diff ticks
71 timestamp += (now - lastinc);
73 /* We have rollover of incrementer */
74 timestamp += (TIMER_LOAD_VAL - lastinc) + now;
81 ulong get_timer(ulong base)
83 return tick_to_time(get_ticks()) - base;
86 void __udelay(unsigned long usec)
88 unsigned long long tmp;
91 tmo = us_to_tick(usec);
92 tmp = get_ticks() + tmo; /* get current timestamp */
94 while (get_ticks() < tmp) /* loop till event */
100 return TIMER_FREQ_HZ;