xref: /OK3568_Linux_fs/u-boot/drivers/timer/altera_timer.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * (C) Copyright 2000-2002
3*4882a593Smuzhiyun  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * (C) Copyright 2004, Psyent Corporation <www.psyent.com>
6*4882a593Smuzhiyun  * Scott McNutt <smcnutt@psyent.com>
7*4882a593Smuzhiyun  *
8*4882a593Smuzhiyun  * SPDX-License-Identifier:	GPL-2.0+
9*4882a593Smuzhiyun  */
10*4882a593Smuzhiyun 
11*4882a593Smuzhiyun #include <common.h>
12*4882a593Smuzhiyun #include <dm.h>
13*4882a593Smuzhiyun #include <errno.h>
14*4882a593Smuzhiyun #include <timer.h>
15*4882a593Smuzhiyun #include <asm/io.h>
16*4882a593Smuzhiyun 
17*4882a593Smuzhiyun DECLARE_GLOBAL_DATA_PTR;
18*4882a593Smuzhiyun 
19*4882a593Smuzhiyun /* control register */
20*4882a593Smuzhiyun #define ALTERA_TIMER_CONT	BIT(1)	/* Continuous mode */
21*4882a593Smuzhiyun #define ALTERA_TIMER_START	BIT(2)	/* Start timer */
22*4882a593Smuzhiyun #define ALTERA_TIMER_STOP	BIT(3)	/* Stop timer */
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun struct altera_timer_regs {
25*4882a593Smuzhiyun 	u32	status;		/* Timer status reg */
26*4882a593Smuzhiyun 	u32	control;	/* Timer control reg */
27*4882a593Smuzhiyun 	u32	periodl;	/* Timeout period low */
28*4882a593Smuzhiyun 	u32	periodh;	/* Timeout period high */
29*4882a593Smuzhiyun 	u32	snapl;		/* Snapshot low */
30*4882a593Smuzhiyun 	u32	snaph;		/* Snapshot high */
31*4882a593Smuzhiyun };
32*4882a593Smuzhiyun 
33*4882a593Smuzhiyun struct altera_timer_platdata {
34*4882a593Smuzhiyun 	struct altera_timer_regs *regs;
35*4882a593Smuzhiyun };
36*4882a593Smuzhiyun 
altera_timer_get_count(struct udevice * dev,u64 * count)37*4882a593Smuzhiyun static int altera_timer_get_count(struct udevice *dev, u64 *count)
38*4882a593Smuzhiyun {
39*4882a593Smuzhiyun 	struct altera_timer_platdata *plat = dev->platdata;
40*4882a593Smuzhiyun 	struct altera_timer_regs *const regs = plat->regs;
41*4882a593Smuzhiyun 	u32 val;
42*4882a593Smuzhiyun 
43*4882a593Smuzhiyun 	/* Trigger update */
44*4882a593Smuzhiyun 	writel(0x0, &regs->snapl);
45*4882a593Smuzhiyun 
46*4882a593Smuzhiyun 	/* Read timer value */
47*4882a593Smuzhiyun 	val = readl(&regs->snapl) & 0xffff;
48*4882a593Smuzhiyun 	val |= (readl(&regs->snaph) & 0xffff) << 16;
49*4882a593Smuzhiyun 	*count = timer_conv_64(~val);
50*4882a593Smuzhiyun 
51*4882a593Smuzhiyun 	return 0;
52*4882a593Smuzhiyun }
53*4882a593Smuzhiyun 
altera_timer_probe(struct udevice * dev)54*4882a593Smuzhiyun static int altera_timer_probe(struct udevice *dev)
55*4882a593Smuzhiyun {
56*4882a593Smuzhiyun 	struct altera_timer_platdata *plat = dev->platdata;
57*4882a593Smuzhiyun 	struct altera_timer_regs *const regs = plat->regs;
58*4882a593Smuzhiyun 
59*4882a593Smuzhiyun 	writel(0, &regs->status);
60*4882a593Smuzhiyun 	writel(0, &regs->control);
61*4882a593Smuzhiyun 	writel(ALTERA_TIMER_STOP, &regs->control);
62*4882a593Smuzhiyun 
63*4882a593Smuzhiyun 	writel(0xffff, &regs->periodl);
64*4882a593Smuzhiyun 	writel(0xffff, &regs->periodh);
65*4882a593Smuzhiyun 	writel(ALTERA_TIMER_CONT | ALTERA_TIMER_START, &regs->control);
66*4882a593Smuzhiyun 
67*4882a593Smuzhiyun 	return 0;
68*4882a593Smuzhiyun }
69*4882a593Smuzhiyun 
altera_timer_ofdata_to_platdata(struct udevice * dev)70*4882a593Smuzhiyun static int altera_timer_ofdata_to_platdata(struct udevice *dev)
71*4882a593Smuzhiyun {
72*4882a593Smuzhiyun 	struct altera_timer_platdata *plat = dev_get_platdata(dev);
73*4882a593Smuzhiyun 
74*4882a593Smuzhiyun 	plat->regs = map_physmem(devfdt_get_addr(dev),
75*4882a593Smuzhiyun 				 sizeof(struct altera_timer_regs),
76*4882a593Smuzhiyun 				 MAP_NOCACHE);
77*4882a593Smuzhiyun 
78*4882a593Smuzhiyun 	return 0;
79*4882a593Smuzhiyun }
80*4882a593Smuzhiyun 
81*4882a593Smuzhiyun static const struct timer_ops altera_timer_ops = {
82*4882a593Smuzhiyun 	.get_count = altera_timer_get_count,
83*4882a593Smuzhiyun };
84*4882a593Smuzhiyun 
85*4882a593Smuzhiyun static const struct udevice_id altera_timer_ids[] = {
86*4882a593Smuzhiyun 	{ .compatible = "altr,timer-1.0" },
87*4882a593Smuzhiyun 	{}
88*4882a593Smuzhiyun };
89*4882a593Smuzhiyun 
90*4882a593Smuzhiyun U_BOOT_DRIVER(altera_timer) = {
91*4882a593Smuzhiyun 	.name	= "altera_timer",
92*4882a593Smuzhiyun 	.id	= UCLASS_TIMER,
93*4882a593Smuzhiyun 	.of_match = altera_timer_ids,
94*4882a593Smuzhiyun 	.ofdata_to_platdata = altera_timer_ofdata_to_platdata,
95*4882a593Smuzhiyun 	.platdata_auto_alloc_size = sizeof(struct altera_timer_platdata),
96*4882a593Smuzhiyun 	.probe = altera_timer_probe,
97*4882a593Smuzhiyun 	.ops	= &altera_timer_ops,
98*4882a593Smuzhiyun 	.flags = DM_FLAG_PRE_RELOC,
99*4882a593Smuzhiyun };
100