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 <common.h>
8 #include <clk.h>
9 #include <dm.h>
10 #include <timer.h>
11 #include <asm/io.h>
12 #include <linux/bitops.h>
13
14 #define AT91_PIT_VALUE 0xfffff
15 #define AT91_PIT_PITEN BIT(24) /* Timer Enabled */
16
17 struct atmel_pit_regs {
18 u32 mode;
19 u32 status;
20 u32 value;
21 u32 value_image;
22 };
23
24 struct atmel_pit_plat {
25 struct atmel_pit_regs *regs;
26 };
27
atmel_pit_get_count(struct udevice * dev)28 static u64 atmel_pit_get_count(struct udevice *dev)
29 {
30 struct atmel_pit_plat *plat = dev_get_plat(dev);
31 struct atmel_pit_regs *const regs = plat->regs;
32 u32 val = readl(®s->value_image);
33
34 return timer_conv_64(val);
35 }
36
atmel_pit_probe(struct udevice * dev)37 static int atmel_pit_probe(struct udevice *dev)
38 {
39 struct atmel_pit_plat *plat = dev_get_plat(dev);
40 struct atmel_pit_regs *const regs = plat->regs;
41 struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
42 struct clk clk;
43 ulong clk_rate;
44 int ret;
45
46 ret = clk_get_by_index(dev, 0, &clk);
47 if (ret)
48 return -EINVAL;
49
50 clk_rate = clk_get_rate(&clk);
51 if (!clk_rate)
52 return -EINVAL;
53
54 uc_priv->clock_rate = clk_rate / 16;
55
56 writel(AT91_PIT_VALUE | AT91_PIT_PITEN, ®s->mode);
57
58 return 0;
59 }
60
atmel_pit_of_to_plat(struct udevice * dev)61 static int atmel_pit_of_to_plat(struct udevice *dev)
62 {
63 struct atmel_pit_plat *plat = dev_get_plat(dev);
64
65 plat->regs = dev_read_addr_ptr(dev);
66
67 return 0;
68 }
69
70 static const struct timer_ops atmel_pit_ops = {
71 .get_count = atmel_pit_get_count,
72 };
73
74 static const struct udevice_id atmel_pit_ids[] = {
75 { .compatible = "atmel,at91sam9260-pit" },
76 { }
77 };
78
79 U_BOOT_DRIVER(atmel_pit) = {
80 .name = "atmel_pit",
81 .id = UCLASS_TIMER,
82 .of_match = atmel_pit_ids,
83 .of_to_plat = atmel_pit_of_to_plat,
84 .plat_auto = sizeof(struct atmel_pit_plat),
85 .probe = atmel_pit_probe,
86 .ops = &atmel_pit_ops,
87 };
88