// SPDX-License-Identifier: GPL-2.0+ /* * (C) Copyright 2008 * Texas Instruments * * Richard Woodruff <r-woodruff2@ti.com> * Syed Moahmmed Khasim <khasim@ti.com> * * (C) Copyright 2002 * Sysgo Real-Time Solutions, GmbH <www.elinos.com> * Marius Groeger <mgroeger@sysgo.de> * Alex Zuepke <azu@sysgo.de> * * (C) Copyright 2002 * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de> */ #include <common.h> #include <init.h> #include <time.h> #include <asm/global_data.h> #include <asm/io.h> #include <asm/arch/cpu.h> #include <asm/arch/clock.h> #include <asm/omap_common.h> #include <linux/delay.h> DECLARE_GLOBAL_DATA_PTR; static struct gptimer *timer_base = (struct gptimer *)CFG_SYS_TIMERBASE; static ulong get_timer_masked(void); /* * Nothing really to do with interrupts, just starts up a counter. */ #define TIMER_CLOCK (V_SCLK / (2 << SYS_PTV)) #define TIMER_OVERFLOW_VAL 0xffffffff #define TIMER_LOAD_VAL 0 int timer_init(void) { /* start the counter ticking up, reload value on overflow */ writel(TIMER_LOAD_VAL, &timer_base->tldr); /* enable timer */ writel((SYS_PTV << 2) | TCLR_PRE | TCLR_AR | TCLR_ST, &timer_base->tclr); return 0; } /* * timer without interrupts */ ulong get_timer(ulong base) { return get_timer_masked() - base; } /* delay x useconds */ void __udelay(unsigned long usec) { long tmo = usec * (TIMER_CLOCK / 1000) / 1000; unsigned long now, last = readl(&timer_base->tcrr); while (tmo > 0) { now = readl(&timer_base->tcrr); if (last > now) /* count up timer overflow */ tmo -= TIMER_OVERFLOW_VAL - last + now + 1; else tmo -= now - last; last = now; } } static ulong get_timer_masked(void) { /* current tick value */ ulong now = readl(&timer_base->tcrr) / (TIMER_CLOCK / CONFIG_SYS_HZ); if (now >= gd->arch.lastinc) { /* normal mode (non roll) */ /* move stamp fordward with absoulte diff ticks */ gd->arch.tbl += (now - gd->arch.lastinc); } else { /* we have rollover of incrementer */ gd->arch.tbl += ((TIMER_OVERFLOW_VAL / (TIMER_CLOCK / CONFIG_SYS_HZ)) - gd->arch.lastinc) + now; } gd->arch.lastinc = now; return gd->arch.tbl; } /* * This function is derived from PowerPC code (read timebase as long long). * On ARM it just returns the timer value. */ unsigned long long get_ticks(void) { return get_timer(0); } /* * This function is derived from PowerPC code (timebase clock frequency). * On ARM it returns the number of timer ticks per second. */ ulong get_tbclk(void) { return CONFIG_SYS_HZ; }