xref: /openbmc/linux/arch/mips/pic32/pic32mzda/time.c (revision 2359ccdd)
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 
25 static const struct of_device_id pic32_infra_match[] = {
26 	{ .compatible = "microchip,pic32mzda-infra", },
27 	{ },
28 };
29 
30 #define DEFAULT_CORE_TIMER_INTERRUPT 0
31 
32 static 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 
48 default_map:
49 
50 	return irq_create_mapping(NULL, DEFAULT_CORE_TIMER_INTERRUPT);
51 }
52 
53 unsigned int get_c0_compare_int(void)
54 {
55 	return pic32_xlate_core_timer_irq();
56 }
57 
58 void __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