5 * Richard Woodruff <r-woodruff2@ti.com>
6 * Syed Moahmmed Khasim <khasim@ti.com>
9 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
10 * Marius Groeger <mgroeger@sysgo.de>
11 * Alex Zuepke <azu@sysgo.de>
14 * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
16 * See file CREDITS for list of people who contributed to this
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.
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.
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,
38 #include <asm/arch/cpu.h>
40 DECLARE_GLOBAL_DATA_PTR;
42 static struct gptimer *timer_base = (struct gptimer *)CONFIG_SYS_TIMERBASE;
45 * Nothing really to do with interrupts, just starts up a counter.
48 #if CONFIG_SYS_PTV > 7
49 #error Invalid CONFIG_SYS_PTV value
50 #elif CONFIG_SYS_PTV >= 0
51 #define TIMER_CLOCK (V_SCLK / (2 << CONFIG_SYS_PTV))
52 #define TCLR_VAL ((CONFIG_SYS_PTV << 2) | TCLR_PRE | TCLR_AR | TCLR_ST)
54 #define TIMER_CLOCK V_SCLK
55 #define TCLR_VAL (TCLR_AR | TCLR_ST)
57 #define TIMER_LOAD_VAL 0
59 #if TIMER_CLOCK < CONFIG_SYS_HZ
60 #error TIMER_CLOCK must be > CONFIG_SYS_HZ
64 * Start timer so that it will overflow 15 sec after boot,
65 * to catch misbehaving timer code early on!
67 #define TIMER_START (-time_to_tick(15 * CONFIG_SYS_HZ))
69 static inline unsigned long tick_to_time(unsigned long tick)
71 return tick / (TIMER_CLOCK / CONFIG_SYS_HZ);
74 static inline unsigned long time_to_tick(unsigned long time)
76 return time * (TIMER_CLOCK / CONFIG_SYS_HZ);
79 static inline unsigned long us_to_ticks(unsigned long usec)
81 return usec * (TIMER_CLOCK / CONFIG_SYS_HZ / 1000);
86 #if !defined(CONFIG_SPL) || defined(CONFIG_SPL_BUILD)
88 writel(0x2, &timer_base->tscir);
90 /* Wait until the reset is done */
91 while (readl(&timer_base->tiocp_cfg) & 1)
94 /* preload the counter to make overflow occur early */
95 writel(TIMER_START, &timer_base->tldr);
96 writel(~0, &timer_base->ttgr);
98 /* start the counter ticking up, reload value on overflow */
99 writel(TIMER_LOAD_VAL, &timer_base->tldr);
101 writel(TCLR_VAL, &timer_base->tclr);
103 #ifndef CONFIG_SPL_BUILD
104 gd->lastinc = -30 * TIMER_CLOCK;
105 gd->tbl = TIMER_START;
106 gd->timer_rate_hz = TIMER_CLOCK;
112 * timer without interrupts
114 ulong get_timer(ulong base)
116 return tick_to_time(get_ticks() - time_to_tick(base));
119 /* delay x useconds */
120 void __udelay(unsigned long usec)
122 unsigned long start = readl(&timer_base->tcrr);
123 unsigned long ticks = us_to_ticks(usec);
131 while (readl(&timer_base->tcrr) - start < ticks)
135 ulong get_timer_masked(void)
137 /* current tick value */
138 return tick_to_time(get_ticks());
142 * This function is derived from PowerPC code (read timebase as long long).
143 * On ARM it just returns the timer value.
145 unsigned long long get_ticks(void)
147 ulong now = readl(&timer_base->tcrr);
148 ulong inc = now - gd->lastinc;
156 * This function is derived from PowerPC code (timebase clock frequency).
157 * On ARM it returns the number of timer ticks per second.
159 ulong get_tbclk(void)
161 return gd->timer_rate_hz;