/* SPDX-License-Identifier: BSD-2-Clause */
/**
* @file
*
* @ingroup RTEMSBSPsMicroblaze
*
* @brief MicroBlaze AXI Timer clock support
*/
/*
* Copyright (C) 2021 On-Line Applications Research Corporation (OAR)
*
* 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 <bsp/fatal.h>
#include <bsp/timer.h>
#include <rtems.h>
#include <rtems/irq-extension.h>
#include <rtems/timecounter.h>
static rtems_timecounter_simple mblaze_tc;
static uint32_t microblaze_tc_get( rtems_timecounter_simple *tc )
{
volatile Microblaze_Timer *timer = _Microblaze_Timer;
return timer->tcr0;
}
static bool microblaze_tc_is_pending( rtems_timecounter_simple *tc )
{
volatile Microblaze_Timer *timer = _Microblaze_Timer;
return ( timer->tcsr0 & MICROBLAZE_TIMER_TCSR0_T0INT ) != 0;
}
static uint32_t microblaze_tc_get_timecount( struct timecounter *tc )
{
return rtems_timecounter_simple_downcounter_get(
tc,
microblaze_tc_get,
microblaze_tc_is_pending
);
}
static void microblaze_clock_initialize( void )
{
volatile Microblaze_Timer *timer = _Microblaze_Timer;
/* Set load register to 0 */
timer->tlr0 = 0;
/* Reset the timer and interrupt */
timer->tcsr0 = MICROBLAZE_TIMER_TCSR0_T0INT | MICROBLAZE_TIMER_TCSR0_LOAD0;
/* Release the reset */
timer->tcsr0 = 0;
/*
* Enable interrupt, auto reload mode, external interrupt signal,
* and down counter
*/
timer->tcsr0 = MICROBLAZE_TIMER_TCSR0_ARHT0 | MICROBLAZE_TIMER_TCSR0_ENIT0 |
MICROBLAZE_TIMER_TCSR0_GENT0 | MICROBLAZE_TIMER_TCSR0_UDT0;
uint64_t us_per_tick = rtems_configuration_get_microseconds_per_tick();
uint32_t counter_frequency_in_hz = BSP_MICROBLAZE_FPGA_TIMER_FREQUENCY;
uint32_t counter_ticks_per_clock_tick =
( counter_frequency_in_hz * us_per_tick ) / 1000000;
/* Set a reset value for the timer counter */
timer->tlr0 = counter_ticks_per_clock_tick;
uint32_t control_status_reg = timer->tcsr0;
/* Load the reset value into the counter register */
timer->tcsr0 = MICROBLAZE_TIMER_TCSR0_LOAD0;
/* Enable the timer */
timer->tcsr0 = control_status_reg | MICROBLAZE_TIMER_TCSR0_ENT0;
rtems_timecounter_simple_install(
&mblaze_tc,
counter_frequency_in_hz,
counter_ticks_per_clock_tick,
microblaze_tc_get_timecount
);
}
static void microblaze_clock_at_tick( rtems_timecounter_simple *tc )
{
volatile Microblaze_Timer *timer = _Microblaze_Timer;
if ( ( timer->tcsr0 & MICROBLAZE_TIMER_TCSR0_T0INT ) == 0 ) {
return;
}
/* Clear the interrupt */
timer->tcsr0 |= MICROBLAZE_TIMER_TCSR0_T0INT;
}
static void microblaze_tc_tick( void )
{
rtems_timecounter_simple_downcounter_tick(
&mblaze_tc,
microblaze_tc_get,
microblaze_clock_at_tick
);
}
static void microblaze_clock_handler_install( rtems_interrupt_handler isr )
{
rtems_status_code sc = RTEMS_SUCCESSFUL;
sc = rtems_interrupt_handler_install(
0,
"Clock",
RTEMS_INTERRUPT_UNIQUE,
isr,
NULL
);
if ( sc != RTEMS_SUCCESSFUL ) {
bsp_fatal( MICROBLAZE_FATAL_CLOCK_IRQ_INSTALL );
}
}
#define Clock_driver_support_initialize_hardware() microblaze_clock_initialize()
#define Clock_driver_support_install_isr( isr ) \
microblaze_clock_handler_install( isr )
#define Clock_driver_timecounter_tick() microblaze_tc_tick()
/* Include shared source clock driver code */
#include "../../shared/dev/clock/clockimpl.h"