1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun * Copyright (C) 2015 Freescale Semiconductor, Inc.
3*4882a593Smuzhiyun *
4*4882a593Smuzhiyun * SPDX-License-Identifier: GPL-2.0+
5*4882a593Smuzhiyun *
6*4882a593Smuzhiyun * The file use ls102xa/timer.c as a reference.
7*4882a593Smuzhiyun */
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun #include <common.h>
10*4882a593Smuzhiyun #include <asm/io.h>
11*4882a593Smuzhiyun #include <div64.h>
12*4882a593Smuzhiyun #include <asm/arch/imx-regs.h>
13*4882a593Smuzhiyun #include <asm/arch/sys_proto.h>
14*4882a593Smuzhiyun #include <asm/mach-imx/syscounter.h>
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun DECLARE_GLOBAL_DATA_PTR;
17*4882a593Smuzhiyun
18*4882a593Smuzhiyun /*
19*4882a593Smuzhiyun * This function is intended for SHORT delays only.
20*4882a593Smuzhiyun * It will overflow at around 10 seconds @ 400MHz,
21*4882a593Smuzhiyun * or 20 seconds @ 200MHz.
22*4882a593Smuzhiyun */
usec2ticks(unsigned long usec)23*4882a593Smuzhiyun unsigned long usec2ticks(unsigned long usec)
24*4882a593Smuzhiyun {
25*4882a593Smuzhiyun ulong ticks;
26*4882a593Smuzhiyun
27*4882a593Smuzhiyun if (usec < 1000)
28*4882a593Smuzhiyun ticks = ((usec * (get_tbclk()/1000)) + 500) / 1000;
29*4882a593Smuzhiyun else
30*4882a593Smuzhiyun ticks = ((usec / 10) * (get_tbclk() / 100000));
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun return ticks;
33*4882a593Smuzhiyun }
34*4882a593Smuzhiyun
tick_to_time(unsigned long long tick)35*4882a593Smuzhiyun static inline unsigned long long tick_to_time(unsigned long long tick)
36*4882a593Smuzhiyun {
37*4882a593Smuzhiyun unsigned long freq;
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (freq));
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun tick *= CONFIG_SYS_HZ;
42*4882a593Smuzhiyun do_div(tick, freq);
43*4882a593Smuzhiyun
44*4882a593Smuzhiyun return tick;
45*4882a593Smuzhiyun }
46*4882a593Smuzhiyun
us_to_tick(unsigned long long usec)47*4882a593Smuzhiyun static inline unsigned long long us_to_tick(unsigned long long usec)
48*4882a593Smuzhiyun {
49*4882a593Smuzhiyun unsigned long freq;
50*4882a593Smuzhiyun
51*4882a593Smuzhiyun asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (freq));
52*4882a593Smuzhiyun
53*4882a593Smuzhiyun usec = usec * freq + 999999;
54*4882a593Smuzhiyun do_div(usec, 1000000);
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun return usec;
57*4882a593Smuzhiyun }
58*4882a593Smuzhiyun
timer_init(void)59*4882a593Smuzhiyun int timer_init(void)
60*4882a593Smuzhiyun {
61*4882a593Smuzhiyun struct sctr_regs *sctr = (struct sctr_regs *)SCTR_BASE_ADDR;
62*4882a593Smuzhiyun unsigned long val, freq;
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun freq = CONFIG_SC_TIMER_CLK;
65*4882a593Smuzhiyun asm("mcr p15, 0, %0, c14, c0, 0" : : "r" (freq));
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun writel(freq, &sctr->cntfid0);
68*4882a593Smuzhiyun
69*4882a593Smuzhiyun /* Enable system counter */
70*4882a593Smuzhiyun val = readl(&sctr->cntcr);
71*4882a593Smuzhiyun val &= ~(SC_CNTCR_FREQ0 | SC_CNTCR_FREQ1);
72*4882a593Smuzhiyun val |= SC_CNTCR_FREQ0 | SC_CNTCR_ENABLE | SC_CNTCR_HDBG;
73*4882a593Smuzhiyun writel(val, &sctr->cntcr);
74*4882a593Smuzhiyun
75*4882a593Smuzhiyun gd->arch.tbl = 0;
76*4882a593Smuzhiyun gd->arch.tbu = 0;
77*4882a593Smuzhiyun
78*4882a593Smuzhiyun return 0;
79*4882a593Smuzhiyun }
80*4882a593Smuzhiyun
get_ticks(void)81*4882a593Smuzhiyun unsigned long long get_ticks(void)
82*4882a593Smuzhiyun {
83*4882a593Smuzhiyun unsigned long long now;
84*4882a593Smuzhiyun
85*4882a593Smuzhiyun asm("mrrc p15, 0, %Q0, %R0, c14" : "=r" (now));
86*4882a593Smuzhiyun
87*4882a593Smuzhiyun gd->arch.tbl = (unsigned long)(now & 0xffffffff);
88*4882a593Smuzhiyun gd->arch.tbu = (unsigned long)(now >> 32);
89*4882a593Smuzhiyun
90*4882a593Smuzhiyun return now;
91*4882a593Smuzhiyun }
92*4882a593Smuzhiyun
get_timer_masked(void)93*4882a593Smuzhiyun ulong get_timer_masked(void)
94*4882a593Smuzhiyun {
95*4882a593Smuzhiyun return tick_to_time(get_ticks());
96*4882a593Smuzhiyun }
97*4882a593Smuzhiyun
get_timer(ulong base)98*4882a593Smuzhiyun ulong get_timer(ulong base)
99*4882a593Smuzhiyun {
100*4882a593Smuzhiyun return get_timer_masked() - base;
101*4882a593Smuzhiyun }
102*4882a593Smuzhiyun
__udelay(unsigned long usec)103*4882a593Smuzhiyun void __udelay(unsigned long usec)
104*4882a593Smuzhiyun {
105*4882a593Smuzhiyun unsigned long long tmp;
106*4882a593Smuzhiyun ulong tmo;
107*4882a593Smuzhiyun
108*4882a593Smuzhiyun tmo = us_to_tick(usec);
109*4882a593Smuzhiyun tmp = get_ticks() + tmo; /* get current timestamp */
110*4882a593Smuzhiyun
111*4882a593Smuzhiyun while (get_ticks() < tmp) /* loop till event */
112*4882a593Smuzhiyun /*NOP*/;
113*4882a593Smuzhiyun }
114*4882a593Smuzhiyun
115*4882a593Smuzhiyun /*
116*4882a593Smuzhiyun * This function is derived from PowerPC code (timebase clock frequency).
117*4882a593Smuzhiyun * On ARM it returns the number of timer ticks per second.
118*4882a593Smuzhiyun */
get_tbclk(void)119*4882a593Smuzhiyun ulong get_tbclk(void)
120*4882a593Smuzhiyun {
121*4882a593Smuzhiyun unsigned long freq;
122*4882a593Smuzhiyun
123*4882a593Smuzhiyun asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (freq));
124*4882a593Smuzhiyun
125*4882a593Smuzhiyun return freq;
126*4882a593Smuzhiyun }
127