xref: /openbmc/u-boot/arch/sh/lib/time.c (revision ee943655)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2009
4  * Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
5  *
6  * (C) Copyright 2007-2012
7  * Nobobuhiro Iwamatsu <iwamatsu@nigauri.org>
8  *
9  * (C) Copyright 2003
10  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
11  */
12 
13 #include <common.h>
14 #include <asm/processor.h>
15 #include <asm/io.h>
16 #include <sh_tmu.h>
17 
18 #define TCR_TPSC 0x07
19 
20 static struct tmu_regs *tmu = (struct tmu_regs *)TMU_BASE;
21 
22 unsigned long get_tbclk(void)
23 {
24 	u16 tmu_bit = (ffs(CONFIG_SYS_TMU_CLK_DIV) >> 1) - 1;
25 	return get_tmu0_clk_rate() >> ((tmu_bit + 1) * 2);
26 }
27 
28 unsigned long timer_read_counter(void)
29 {
30 	return ~readl(&tmu->tcnt0);
31 }
32 
33 static void tmu_timer_start(unsigned int timer)
34 {
35 	if (timer > 2)
36 		return;
37 	writeb(readb(&tmu->tstr) | (1 << timer), &tmu->tstr);
38 }
39 
40 static void tmu_timer_stop(unsigned int timer)
41 {
42 	if (timer > 2)
43 		return;
44 	writeb(readb(&tmu->tstr) & ~(1 << timer), &tmu->tstr);
45 }
46 
47 int timer_init(void)
48 {
49 	u16 tmu_bit = (ffs(CONFIG_SYS_TMU_CLK_DIV) >> 1) - 1;
50 	writew((readw(&tmu->tcr0) & ~TCR_TPSC) | tmu_bit, &tmu->tcr0);
51 
52 	tmu_timer_stop(0);
53 	tmu_timer_start(0);
54 
55 	return 0;
56 }
57 
58