1*552a848eSStefano Babic /*
2*552a848eSStefano Babic * Copyright (C) 2015 Freescale Semiconductor, Inc.
3*552a848eSStefano Babic *
4*552a848eSStefano Babic * SPDX-License-Identifier: GPL-2.0+
5*552a848eSStefano Babic *
6*552a848eSStefano Babic * The file use ls102xa/timer.c as a reference.
7*552a848eSStefano Babic */
8*552a848eSStefano Babic
9*552a848eSStefano Babic #include <common.h>
10*552a848eSStefano Babic #include <asm/io.h>
11*552a848eSStefano Babic #include <div64.h>
12*552a848eSStefano Babic #include <asm/arch/imx-regs.h>
13*552a848eSStefano Babic #include <asm/arch/sys_proto.h>
14*552a848eSStefano Babic #include <asm/mach-imx/syscounter.h>
15*552a848eSStefano Babic
16*552a848eSStefano Babic DECLARE_GLOBAL_DATA_PTR;
17*552a848eSStefano Babic
18*552a848eSStefano Babic /*
19*552a848eSStefano Babic * This function is intended for SHORT delays only.
20*552a848eSStefano Babic * It will overflow at around 10 seconds @ 400MHz,
21*552a848eSStefano Babic * or 20 seconds @ 200MHz.
22*552a848eSStefano Babic */
usec2ticks(unsigned long usec)23*552a848eSStefano Babic unsigned long usec2ticks(unsigned long usec)
24*552a848eSStefano Babic {
25*552a848eSStefano Babic ulong ticks;
26*552a848eSStefano Babic
27*552a848eSStefano Babic if (usec < 1000)
28*552a848eSStefano Babic ticks = ((usec * (get_tbclk()/1000)) + 500) / 1000;
29*552a848eSStefano Babic else
30*552a848eSStefano Babic ticks = ((usec / 10) * (get_tbclk() / 100000));
31*552a848eSStefano Babic
32*552a848eSStefano Babic return ticks;
33*552a848eSStefano Babic }
34*552a848eSStefano Babic
tick_to_time(unsigned long long tick)35*552a848eSStefano Babic static inline unsigned long long tick_to_time(unsigned long long tick)
36*552a848eSStefano Babic {
37*552a848eSStefano Babic unsigned long freq;
38*552a848eSStefano Babic
39*552a848eSStefano Babic asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (freq));
40*552a848eSStefano Babic
41*552a848eSStefano Babic tick *= CONFIG_SYS_HZ;
42*552a848eSStefano Babic do_div(tick, freq);
43*552a848eSStefano Babic
44*552a848eSStefano Babic return tick;
45*552a848eSStefano Babic }
46*552a848eSStefano Babic
us_to_tick(unsigned long long usec)47*552a848eSStefano Babic static inline unsigned long long us_to_tick(unsigned long long usec)
48*552a848eSStefano Babic {
49*552a848eSStefano Babic unsigned long freq;
50*552a848eSStefano Babic
51*552a848eSStefano Babic asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (freq));
52*552a848eSStefano Babic
53*552a848eSStefano Babic usec = usec * freq + 999999;
54*552a848eSStefano Babic do_div(usec, 1000000);
55*552a848eSStefano Babic
56*552a848eSStefano Babic return usec;
57*552a848eSStefano Babic }
58*552a848eSStefano Babic
timer_init(void)59*552a848eSStefano Babic int timer_init(void)
60*552a848eSStefano Babic {
61*552a848eSStefano Babic struct sctr_regs *sctr = (struct sctr_regs *)SCTR_BASE_ADDR;
62*552a848eSStefano Babic unsigned long val, freq;
63*552a848eSStefano Babic
64*552a848eSStefano Babic freq = CONFIG_SC_TIMER_CLK;
65*552a848eSStefano Babic asm("mcr p15, 0, %0, c14, c0, 0" : : "r" (freq));
66*552a848eSStefano Babic
67*552a848eSStefano Babic writel(freq, &sctr->cntfid0);
68*552a848eSStefano Babic
69*552a848eSStefano Babic /* Enable system counter */
70*552a848eSStefano Babic val = readl(&sctr->cntcr);
71*552a848eSStefano Babic val &= ~(SC_CNTCR_FREQ0 | SC_CNTCR_FREQ1);
72*552a848eSStefano Babic val |= SC_CNTCR_FREQ0 | SC_CNTCR_ENABLE | SC_CNTCR_HDBG;
73*552a848eSStefano Babic writel(val, &sctr->cntcr);
74*552a848eSStefano Babic
75*552a848eSStefano Babic gd->arch.tbl = 0;
76*552a848eSStefano Babic gd->arch.tbu = 0;
77*552a848eSStefano Babic
78*552a848eSStefano Babic return 0;
79*552a848eSStefano Babic }
80*552a848eSStefano Babic
get_ticks(void)81*552a848eSStefano Babic unsigned long long get_ticks(void)
82*552a848eSStefano Babic {
83*552a848eSStefano Babic unsigned long long now;
84*552a848eSStefano Babic
85*552a848eSStefano Babic asm("mrrc p15, 0, %Q0, %R0, c14" : "=r" (now));
86*552a848eSStefano Babic
87*552a848eSStefano Babic gd->arch.tbl = (unsigned long)(now & 0xffffffff);
88*552a848eSStefano Babic gd->arch.tbu = (unsigned long)(now >> 32);
89*552a848eSStefano Babic
90*552a848eSStefano Babic return now;
91*552a848eSStefano Babic }
92*552a848eSStefano Babic
get_timer_masked(void)93*552a848eSStefano Babic ulong get_timer_masked(void)
94*552a848eSStefano Babic {
95*552a848eSStefano Babic return tick_to_time(get_ticks());
96*552a848eSStefano Babic }
97*552a848eSStefano Babic
get_timer(ulong base)98*552a848eSStefano Babic ulong get_timer(ulong base)
99*552a848eSStefano Babic {
100*552a848eSStefano Babic return get_timer_masked() - base;
101*552a848eSStefano Babic }
102*552a848eSStefano Babic
__udelay(unsigned long usec)103*552a848eSStefano Babic void __udelay(unsigned long usec)
104*552a848eSStefano Babic {
105*552a848eSStefano Babic unsigned long long tmp;
106*552a848eSStefano Babic ulong tmo;
107*552a848eSStefano Babic
108*552a848eSStefano Babic tmo = us_to_tick(usec);
109*552a848eSStefano Babic tmp = get_ticks() + tmo; /* get current timestamp */
110*552a848eSStefano Babic
111*552a848eSStefano Babic while (get_ticks() < tmp) /* loop till event */
112*552a848eSStefano Babic /*NOP*/;
113*552a848eSStefano Babic }
114*552a848eSStefano Babic
115*552a848eSStefano Babic /*
116*552a848eSStefano Babic * This function is derived from PowerPC code (timebase clock frequency).
117*552a848eSStefano Babic * On ARM it returns the number of timer ticks per second.
118*552a848eSStefano Babic */
get_tbclk(void)119*552a848eSStefano Babic ulong get_tbclk(void)
120*552a848eSStefano Babic {
121*552a848eSStefano Babic unsigned long freq;
122*552a848eSStefano Babic
123*552a848eSStefano Babic asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (freq));
124*552a848eSStefano Babic
125*552a848eSStefano Babic return freq;
126*552a848eSStefano Babic }
127