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>
22 #include <asm/arch/cpu.h>
23 #include <asm/arch/clock.h>
25 DECLARE_GLOBAL_DATA_PTR;
27 static struct gptimer *timer_base = (struct gptimer *)CONFIG_SYS_TIMERBASE;
28 static ulong get_timer_masked(void);
31 * Nothing really to do with interrupts, just starts up a counter.
34 #define TIMER_CLOCK (V_SCLK / (2 << CONFIG_SYS_PTV))
35 #define TIMER_OVERFLOW_VAL 0xffffffff
36 #define TIMER_LOAD_VAL 0
40 /* start the counter ticking up, reload value on overflow */
41 writel(TIMER_LOAD_VAL, &timer_base->tldr);
43 writel((CONFIG_SYS_PTV << 2) | TCLR_PRE | TCLR_AR | TCLR_ST,
50 * timer without interrupts
52 ulong get_timer(ulong base)
54 return get_timer_masked() - base;
57 /* delay x useconds */
58 void __udelay(unsigned long usec)
60 long tmo = usec * (TIMER_CLOCK / 1000) / 1000;
61 unsigned long now, last = readl(&timer_base->tcrr);
64 now = readl(&timer_base->tcrr);
65 if (last > now) /* count up timer overflow */
66 tmo -= TIMER_OVERFLOW_VAL - last + now + 1;
73 static ulong get_timer_masked(void)
75 /* current tick value */
76 ulong now = readl(&timer_base->tcrr) / (TIMER_CLOCK / CONFIG_SYS_HZ);
78 if (now >= gd->arch.lastinc) { /* normal mode (non roll) */
79 /* move stamp fordward with absoulte diff ticks */
80 gd->arch.tbl += (now - gd->arch.lastinc);
81 } else { /* we have rollover of incrementer */
82 gd->arch.tbl += ((TIMER_OVERFLOW_VAL / (TIMER_CLOCK /
83 CONFIG_SYS_HZ)) - gd->arch.lastinc) + now;
85 gd->arch.lastinc = now;
90 * This function is derived from PowerPC code (read timebase as long long).
91 * On ARM it just returns the timer value.
93 unsigned long long get_ticks(void)
99 * This function is derived from PowerPC code (timebase clock frequency).
100 * On ARM it returns the number of timer ticks per second.
102 ulong get_tbclk(void)
104 return CONFIG_SYS_HZ;