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/*
* Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <assert.h>
#include <drivers/delay_timer.h>
#include <lib/mmio.h>
#include <imx_gpt.h>
#define GPTCR_SWR BIT(15) /* Software reset */
#define GPTCR_24MEN BIT(10) /* Enable 24MHz clock input */
#define GPTCR_CLKSOURCE_OSC (5 << 6) /* Clock source OSC */
#define GPTCR_CLKSOURCE_MASK (0x7 << 6)
#define GPTCR_TEN 1 /* Timer enable */
#define GPTPR_PRESCL_24M_SHIFT 12
#define SYS_COUNTER_FREQ_IN_MHZ 3
#define GPTPR_TIMER_CTRL (imx_base_addr + 0x000)
#define GPTPR_TIMER_PRESCL (imx_base_addr + 0x004)
#define GPTPR_TIMER_CNTR (imx_base_addr + 0x024)
static uintptr_t imx_base_addr;
uint32_t imx_get_timer_value(void)
{
return ~mmio_read_32(GPTPR_TIMER_CNTR);
}
static const timer_ops_t imx_gpt_ops = {
.get_timer_value = imx_get_timer_value,
.clk_mult = 1,
.clk_div = SYS_COUNTER_FREQ_IN_MHZ,
};
void imx_gpt_ops_init(uintptr_t base_addr)
{
int val;
assert(base_addr != 0);
imx_base_addr = base_addr;
/* setup GP Timer */
mmio_write_32(GPTPR_TIMER_CTRL, GPTCR_SWR);
mmio_write_32(GPTPR_TIMER_CTRL, 0);
/* get 3MHz from 24MHz */
mmio_write_32(GPTPR_TIMER_PRESCL, (7 << GPTPR_PRESCL_24M_SHIFT));
val = mmio_read_32(GPTPR_TIMER_CTRL);
val &= ~GPTCR_CLKSOURCE_MASK;
val |= GPTCR_24MEN | GPTCR_CLKSOURCE_OSC | GPTCR_TEN;
mmio_write_32(GPTPR_TIMER_CTRL, val);
timer_init(&imx_gpt_ops);
}