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barebox/arch/arm/mach-omap/dmtimer.c

99 lines
2.2 KiB
C

/**
* @file
* @brief Support DMTimer counter
*
* FileName: arch/arm/mach-omap/dmtimer.c
*/
/*
* This File is based on arch/arm/mach-omap/s32k_clksource.c
* (C) Copyright 2008
* Texas Instruments, <www.ti.com>
* Nishanth Menon <x0nishan@ti.com>
*
* (C) Copyright 2012 Phytec Messtechnik GmbH
* Author: Teresa Gámez <t.gamez@phytec.de>
* (C) Copyright 2015 Phytec Messtechnik GmbH
* Author: Daniel Schultz <d.schultz@phytec.de>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#include <clock.h>
#include <init.h>
#include <io.h>
#include <mach/am33xx-silicon.h>
#include <mach/am33xx-clock.h>
#include <stdio.h>
#define CLK_RC32K 32768
#define TIDR 0x0
#define TIOCP_CFG 0x10
#define IRQ_EOI 0x20
#define IRQSTATUS_RAW 0x24
#define IRQSTATUS 0x28
#define IRQSTATUS_SET 0x2c
#define IRQSTATUS_CLR 0x30
#define IRQWAKEEN 0x34
#define TCLR 0x38
#define TCRR 0x3C
#define TLDR 0x40
#define TTGR 0x44
#define TWPS 0x48
#define TMAR 0x4C
#define TCAR1 0x50
#define TSICR 0x54
#define TCAR2 0x58
static void *base = (void *)AM33XX_DMTIMER2_BASE;
/**
* @brief Provide a simple counter read
*
* @return DMTimer counter
*/
static uint64_t dmtimer_read(void)
{
return readl(base + TCRR);
}
static struct clocksource dmtimer_cs = {
.read = dmtimer_read,
.mask = CLOCKSOURCE_MASK(32),
.shift = 10,
};
/**
* @brief Initialize the Clock
*
* Enable dmtimer.
*
* @return result of @ref init_clock
*/
static int dmtimer_init(void)
{
u64 clk_speed;
clk_speed = am33xx_get_osc_clock();
clk_speed *= 1000;
dmtimer_cs.mult = clocksource_hz2mult(clk_speed, dmtimer_cs.shift);
/* Enable counter */
writel(0x3, base + TCLR);
return init_clock(&dmtimer_cs);
}
/* Run me at boot time */
core_initcall(dmtimer_init);