1 // SPDX-License-Identifier: GPL-2.0+
6 * Richard Woodruff <r-woodruff2@ti.com>
7 * Syed Moahmmed Khasim <khasim@ti.com>
10 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
11 * Marius Groeger <mgroeger@sysgo.de>
12 * Alex Zuepke <azu@sysgo.de>
15 * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
20 #include <asm/arch/cpu.h>
21 #include <asm/arch/clock.h>
23 DECLARE_GLOBAL_DATA_PTR;
25 static struct gptimer *timer_base = (struct gptimer *)CONFIG_SYS_TIMERBASE;
28 * Nothing really to do with interrupts, just starts up a counter.
31 #define TIMER_CLOCK (V_SCLK / (2 << CONFIG_SYS_PTV))
32 #define TIMER_OVERFLOW_VAL 0xffffffff
33 #define TIMER_LOAD_VAL 0
37 /* start the counter ticking up, reload value on overflow */
38 writel(TIMER_LOAD_VAL, &timer_base->tldr);
40 writel((CONFIG_SYS_PTV << 2) | TCLR_PRE | TCLR_AR | TCLR_ST,
47 * timer without interrupts
49 ulong get_timer(ulong base)
51 return get_timer_masked() - base;
54 /* delay x useconds */
55 void __udelay(unsigned long usec)
57 long tmo = usec * (TIMER_CLOCK / 1000) / 1000;
58 unsigned long now, last = readl(&timer_base->tcrr);
61 now = readl(&timer_base->tcrr);
62 if (last > now) /* count up timer overflow */
63 tmo -= TIMER_OVERFLOW_VAL - last + now + 1;
70 ulong get_timer_masked(void)
72 /* current tick value */
73 ulong now = readl(&timer_base->tcrr) / (TIMER_CLOCK / CONFIG_SYS_HZ);
75 if (now >= gd->arch.lastinc) { /* normal mode (non roll) */
76 /* move stamp fordward with absoulte diff ticks */
77 gd->arch.tbl += (now - gd->arch.lastinc);
78 } else { /* we have rollover of incrementer */
79 gd->arch.tbl += ((TIMER_OVERFLOW_VAL / (TIMER_CLOCK /
80 CONFIG_SYS_HZ)) - gd->arch.lastinc) + now;
82 gd->arch.lastinc = now;
87 * This function is derived from PowerPC code (read timebase as long long).
88 * On ARM it just returns the timer value.
90 unsigned long long get_ticks(void)
96 * This function is derived from PowerPC code (timebase clock frequency).
97 * On ARM it returns the number of timer ticks per second.
101 return CONFIG_SYS_HZ;