source: rtems/c/src/lib/libbsp/powerpc/t32mppc/clock/clock-config.c @ 7078a00b

/*
 * Copyright (c) 2011, 2017 embedded brains GmbH.  All rights reserved.
 *
 *  embedded brains GmbH
 *  Dornierstr. 4
 *  82178 Puchheim
 *  Germany
 *  <rtems@embedded-brains.de>
 *
 * The license and distribution terms for this file may be
 * found in the file LICENSE in this distribution or at
 * http://www.rtems.org/license/LICENSE.
 */

#include <rtems/timecounter.h>

#include <libcpu/powerpc-utility.h>

#include <bsp.h>
#include <bsp/irq.h>

/* This is defined in clockdrv_shell.h */
static rtems_isr Clock_isr(void *arg);

static struct timecounter t32mppc_clock_tc;

#define CLOCK_DRIVER_USE_ONLY_BOOT_PROCESSOR

void t32mppc_decrementer_dispatch(void)
{
  PPC_SET_SPECIAL_PURPOSE_REGISTER(BOOKE_TSR, BOOKE_TSR_DIS);
  Clock_isr(NULL);
}

static uint32_t t32mppc_clock_get_timecount(struct timecounter *tc)
{
  return ppc_time_base();
}

static void t32mppc_clock_initialize(void)
{
  uint64_t frequency = bsp_time_base_frequency / 10;
  uint32_t us_per_tick = rtems_configuration_get_microseconds_per_tick();
  uint32_t interval = (uint32_t) ((frequency * us_per_tick) / 1000000);

  PPC_SET_SPECIAL_PURPOSE_REGISTER(BOOKE_DECAR, interval - 1);
  PPC_SET_SPECIAL_PURPOSE_REGISTER_BITS(
    BOOKE_TCR,
    BOOKE_TCR_DIE | BOOKE_TCR_ARE
  );
  ppc_set_decrementer_register(interval - 1);

  t32mppc_clock_tc.tc_get_timecount = t32mppc_clock_get_timecount;
  t32mppc_clock_tc.tc_counter_mask = 0xffffffff;
  t32mppc_clock_tc.tc_frequency = bsp_time_base_frequency;
  t32mppc_clock_tc.tc_quality = RTEMS_TIMECOUNTER_QUALITY_CLOCK_DRIVER;
  rtems_timecounter_install(&t32mppc_clock_tc);
}

#define Clock_driver_support_initialize_hardware() \
  t32mppc_clock_initialize()

/* Include shared source clock driver code */
#include "../../../shared/clockdrv_shell.h"