Files
rtems/bsps/arm/shared/clock/clock-nxp-lpc.c
2022-07-08 08:42:42 -05:00

130 lines
3.8 KiB
C

/* SPDX-License-Identifier: BSD-2-Clause */
/**
* @file
*
* @ingroup lpc_clock
*
* @brief Clock driver configuration.
*/
/*
* Copyright (c) 2009-2015 embedded brains GmbH. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <rtems.h>
#include <rtems/timecounter.h>
#include <bsp/lpc-clock-config.h>
#include <bsp/lpc-timer.h>
#ifdef ARM_MULTILIB_ARCH_V4
/* This is defined in ../../../shared/dev/clock/clockimpl.h */
void Clock_isr(rtems_irq_hdl_param arg);
static volatile lpc_timer *const lpc_clock =
(volatile lpc_timer *) LPC_CLOCK_TIMER_BASE;
static volatile lpc_timer *const lpc_timecounter =
(volatile lpc_timer *) LPC_CLOCK_TIMECOUNTER_BASE;
static struct timecounter lpc_clock_tc;
static uint32_t lpc_clock_tc_get_timecount(struct timecounter *tc)
{
return lpc_timecounter->tc;
}
static void lpc_clock_at_tick(void)
{
lpc_clock->ir = LPC_TIMER_IR_MR0;
}
static void lpc_clock_handler_install(void)
{
rtems_status_code sc = RTEMS_SUCCESSFUL;
sc = rtems_interrupt_handler_install(
LPC_CLOCK_INTERRUPT,
"Clock",
RTEMS_INTERRUPT_UNIQUE,
(rtems_interrupt_handler) Clock_isr,
NULL
);
if (sc != RTEMS_SUCCESSFUL) {
rtems_fatal_error_occurred(0xdeadbeef);
}
}
static void lpc_clock_initialize(void)
{
uint64_t interval = ((uint64_t) LPC_CLOCK_REFERENCE
* (uint64_t) rtems_configuration_get_microseconds_per_tick()) / 1000000;
/* Enable module */
LPC_CLOCK_MODULE_ENABLE();
/* Reset timer */
lpc_clock->tcr = LPC_TIMER_TCR_RST;
/* Clear interrupt flags */
lpc_clock->ir = LPC_TIMER_IR_ALL;
/* Set timer mode */
lpc_clock->ccr = 0;
/* Timer is incremented every PERIPH_CLK tick */
lpc_clock->pr = 0;
/* Set match registers */
lpc_clock->mr0 = (uint32_t) interval;
/* Generate interrupt and reset counter on match with MR0 */
lpc_clock->mcr = LPC_TIMER_MCR_MR0_INTR | LPC_TIMER_MCR_MR0_RST;
/* No external match */
lpc_clock->emr = 0x0;
/* Enable timer */
lpc_clock->tcr = LPC_TIMER_TCR_EN;
/* Install timecounter */
lpc_clock_tc.tc_get_timecount = lpc_clock_tc_get_timecount;
lpc_clock_tc.tc_counter_mask = 0xffffffff;
lpc_clock_tc.tc_frequency = LPC_CLOCK_REFERENCE;
lpc_clock_tc.tc_quality = RTEMS_TIMECOUNTER_QUALITY_CLOCK_DRIVER;
rtems_timecounter_install(&lpc_clock_tc);
}
#define Clock_driver_support_at_tick() lpc_clock_at_tick()
#define Clock_driver_support_initialize_hardware() lpc_clock_initialize()
#define Clock_driver_support_install_isr(isr) \
lpc_clock_handler_install()
/* Include shared source clock driver code */
#include "../../../shared/dev/clock/clockimpl.h"
#endif /* ARM_MULTILIB_ARCH_V4 */