xref: /openbmc/u-boot/drivers/timer/mtk_timer.c (revision 286a5c44)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * MediaTek timer driver
4  *
5  * Copyright (C) 2018 MediaTek Inc.
6  * Author: Ryder Lee <ryder.lee@mediatek.com>
7  */
8 
9 #include <clk.h>
10 #include <common.h>
11 #include <dm.h>
12 #include <timer.h>
13 #include <asm/io.h>
14 
15 #define MTK_GPT4_CTRL	0x40
16 #define MTK_GPT4_CLK	0x44
17 #define MTK_GPT4_CNT	0x48
18 
19 #define GPT4_ENABLE	BIT(0)
20 #define GPT4_CLEAR	BIT(1)
21 #define GPT4_FREERUN	GENMASK(5, 4)
22 #define GPT4_CLK_SYS	0x0
23 #define GPT4_CLK_DIV1	0x0
24 
25 struct mtk_timer_priv {
26 	void __iomem *base;
27 };
28 
29 static int mtk_timer_get_count(struct udevice *dev, u64 *count)
30 {
31 	struct mtk_timer_priv *priv = dev_get_priv(dev);
32 	u32 val = readl(priv->base + MTK_GPT4_CNT);
33 
34 	*count = timer_conv_64(val);
35 
36 	return 0;
37 }
38 
39 static int mtk_timer_probe(struct udevice *dev)
40 {
41 	struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
42 	struct mtk_timer_priv *priv = dev_get_priv(dev);
43 	struct clk clk, parent;
44 	int ret;
45 
46 	priv->base = dev_read_addr_ptr(dev);
47 	if (!priv->base)
48 		return -ENOENT;
49 
50 	ret = clk_get_by_index(dev, 0, &clk);
51 	if (ret)
52 		return ret;
53 
54 	ret = clk_get_by_index(dev, 1, &parent);
55 	if (!ret) {
56 		ret = clk_set_parent(&clk, &parent);
57 		if (ret)
58 			return ret;
59 	}
60 
61 	uc_priv->clock_rate = clk_get_rate(&clk);
62 	if (!uc_priv->clock_rate)
63 		return -EINVAL;
64 
65 	return 0;
66 }
67 
68 static const struct timer_ops mtk_timer_ops = {
69 	.get_count = mtk_timer_get_count,
70 };
71 
72 static const struct udevice_id mtk_timer_ids[] = {
73 	{ .compatible = "mediatek,timer" },
74 	{ }
75 };
76 
77 U_BOOT_DRIVER(mtk_timer) = {
78 	.name = "mtk_timer",
79 	.id = UCLASS_TIMER,
80 	.of_match = mtk_timer_ids,
81 	.priv_auto_alloc_size = sizeof(struct mtk_timer_priv),
82 	.probe = mtk_timer_probe,
83 	.ops = &mtk_timer_ops,
84 	.flags = DM_FLAG_PRE_RELOC,
85 };
86