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/*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Marius Groeger <mgroeger@sysgo.de>
*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Alex Zuepke <azu@sysgo.de>
*
* (C) Copyright 2002
* Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
*
* (C) Copyright 2009
* Ilya Yanok, Emcraft Systems Ltd, <yanok@emcraft.com>
*
* (C) Copyright 2009 DENX Software Engineering
* Author: John Rigby <jrigby@gmail.com>
* Add support for MX25
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/io.h>
#include <asm/arch/imx-regs.h>
/* nothing really to do with interrupts, just starts up a counter. */
/* The 32KHz 32-bit timer overruns in 134217 seconds */
int timer_init(void)
{
int i;
struct gpt_regs *gpt = (struct gpt_regs *)IMX_GPT1_BASE;
struct ccm_regs *ccm = (struct ccm_regs *)IMX_CCM_BASE;
/* setup GP Timer 1 */
writel(GPT_CTRL_SWR, &gpt->ctrl);
writel(readl(&ccm->cgr1) | CCM_CGR1_GPT1, &ccm->cgr1);
for (i = 0; i < 100; i++)
writel(0, &gpt->ctrl); /* We have no udelay by now */
writel(0, &gpt->pre); /* prescaler = 1 */
/* Freerun Mode, 32KHz input */
writel(readl(&gpt->ctrl) | GPT_CTRL_CLKSOURCE_32 | GPT_CTRL_FRR,
&gpt->ctrl);
writel(readl(&gpt->ctrl) | GPT_CTRL_TEN, &gpt->ctrl);
return 0;
}
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