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"Das U-Boot" Source Tree
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright (C) 2017 Microchip Corporation
4 * Wenyou.Yang <wenyou.yang@microchip.com>
5 */
6
7#include <clk.h>
8#include <dm.h>
9#include <timer.h>
10#include <asm/io.h>
11#include <linux/bitops.h>
12
13#define AT91_PIT_VALUE 0xfffff
14#define AT91_PIT_PITEN BIT(24) /* Timer Enabled */
15
16struct atmel_pit_regs {
17 u32 mode;
18 u32 status;
19 u32 value;
20 u32 value_image;
21};
22
23struct atmel_pit_plat {
24 struct atmel_pit_regs *regs;
25};
26
27static u64 atmel_pit_get_count(struct udevice *dev)
28{
29 struct atmel_pit_plat *plat = dev_get_plat(dev);
30 struct atmel_pit_regs *const regs = plat->regs;
31 u32 val = readl(®s->value_image);
32
33 return timer_conv_64(val);
34}
35
36static int atmel_pit_probe(struct udevice *dev)
37{
38 struct atmel_pit_plat *plat = dev_get_plat(dev);
39 struct atmel_pit_regs *const regs = plat->regs;
40 struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
41 struct clk clk;
42 ulong clk_rate;
43 int ret;
44
45 ret = clk_get_by_index(dev, 0, &clk);
46 if (ret)
47 return -EINVAL;
48
49 clk_rate = clk_get_rate(&clk);
50 if (!clk_rate)
51 return -EINVAL;
52
53 uc_priv->clock_rate = clk_rate / 16;
54
55 writel(AT91_PIT_VALUE | AT91_PIT_PITEN, ®s->mode);
56
57 return 0;
58}
59
60static int atmel_pit_of_to_plat(struct udevice *dev)
61{
62 struct atmel_pit_plat *plat = dev_get_plat(dev);
63
64 plat->regs = dev_read_addr_ptr(dev);
65
66 return 0;
67}
68
69static const struct timer_ops atmel_pit_ops = {
70 .get_count = atmel_pit_get_count,
71};
72
73static const struct udevice_id atmel_pit_ids[] = {
74 { .compatible = "atmel,at91sam9260-pit" },
75 { }
76};
77
78U_BOOT_DRIVER(atmel_pit) = {
79 .name = "atmel_pit",
80 .id = UCLASS_TIMER,
81 .of_match = atmel_pit_ids,
82 .of_to_plat = atmel_pit_of_to_plat,
83 .plat_auto = sizeof(struct atmel_pit_plat),
84 .probe = atmel_pit_probe,
85 .ops = &atmel_pit_ops,
86};