LXR linux/arch/mips/pic32/pic32mzda/time.c

   1/*
   2 * Joshua Henderson <joshua.henderson@microchip.com>
   3 * Copyright (C) 2015 Microchip Technology Inc.  All rights reserved.
   4 *
   5 *  This program is free software; you can distribute it and/or modify it
   6 *  under the terms of the GNU General Public License (Version 2) as
   7 *  published by the Free Software Foundation.
   8 *
   9 *  This program is distributed in the hope it will be useful, but WITHOUT
  10 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12 *  for more details.
  13 */
  14#include <linux/clk-provider.h>
  15#include <linux/clocksource.h>
  16#include <linux/init.h>
  17#include <linux/irqdomain.h>
  18#include <linux/of.h>
  19#include <linux/of_irq.h>
  20
  21#include <asm/time.h>
  22
  23#include "pic32mzda.h"
  24
  25static const struct of_device_id pic32_infra_match[] = {
  26        { .compatible = "microchip,pic32mzda-infra", },
  27        { },
  28};
  29
  30#define DEFAULT_CORE_TIMER_INTERRUPT 0
  31
  32static unsigned int pic32_xlate_core_timer_irq(void)
  33{
  34        static struct device_node *node;
  35        unsigned int irq;
  36
  37        node = of_find_matching_node(NULL, pic32_infra_match);
  38
  39        if (WARN_ON(!node))
  40                goto default_map;
  41
  42        irq = irq_of_parse_and_map(node, 0);
  43        if (!irq)
  44                goto default_map;
  45
  46        return irq;
  47
  48default_map:
  49
  50        return irq_create_mapping(NULL, DEFAULT_CORE_TIMER_INTERRUPT);
  51}
  52
  53unsigned int get_c0_compare_int(void)
  54{
  55        return pic32_xlate_core_timer_irq();
  56}
  57
  58void __init plat_time_init(void)
  59{
  60        unsigned long rate = pic32_get_pbclk(7);
  61
  62        of_clk_init(NULL);
  63
  64        pr_info("CPU Clock: %ldMHz\n", rate / 1000000);
  65        mips_hpt_frequency = rate / 2;
  66
  67        timer_probe();
  68}
  69