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"Das U-Boot" Source Tree
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright 2022 StarFive, Inc. All rights reserved.
4 * Author: Kuan Lim Lee <kuanlim.lee@starfivetech.com>
5 */
6
7#include <clk.h>
8#include <dm.h>
9#include <time.h>
10#include <timer.h>
11#include <asm/io.h>
12#include <dm/device-internal.h>
13#include <linux/err.h>
14
15#define STF_TIMER_INT_STATUS 0x00
16#define STF_TIMER_CTL 0x04
17#define STF_TIMER_LOAD 0x08
18#define STF_TIMER_ENABLE 0x10
19#define STF_TIMER_RELOAD 0x14
20#define STF_TIMER_VALUE 0x18
21#define STF_TIMER_INT_CLR 0x20
22#define STF_TIMER_INT_MASK 0x24
23
24struct starfive_timer_priv {
25 void __iomem *base;
26 u32 timer_size;
27};
28
29static u64 notrace starfive_get_count(struct udevice *dev)
30{
31 struct starfive_timer_priv *priv = dev_get_priv(dev);
32
33 /* Read decrement timer value and convert to increment value */
34 return priv->timer_size - readl(priv->base + STF_TIMER_VALUE);
35}
36
37static const struct timer_ops starfive_ops = {
38 .get_count = starfive_get_count,
39};
40
41static int starfive_probe(struct udevice *dev)
42{
43 struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
44 struct starfive_timer_priv *priv = dev_get_priv(dev);
45 int timer_channel;
46 struct clk clk;
47 int ret;
48
49 priv->base = dev_read_addr_ptr(dev);
50 if (!priv->base)
51 return -EINVAL;
52
53 timer_channel = dev_read_u32_default(dev, "channel", 0);
54 priv->base = priv->base + (0x40 * timer_channel);
55
56 /* Get clock rate from channel selectecd*/
57 ret = clk_get_by_index(dev, timer_channel, &clk);
58 if (ret)
59 return ret;
60
61 ret = clk_enable(&clk);
62 if (ret)
63 return ret;
64 uc_priv->clock_rate = clk_get_rate(&clk);
65
66 /*
67 * Initiate timer, channel 0
68 * Unmask Interrupt Mask
69 */
70 writel(0, priv->base + STF_TIMER_INT_MASK);
71 /* Single run mode Setting */
72 if (dev_read_bool(dev, "single-run"))
73 writel(1, priv->base + STF_TIMER_CTL);
74 /* Set Reload value */
75 priv->timer_size = dev_read_u32_default(dev, "timer-size", -1U);
76 writel(priv->timer_size, priv->base + STF_TIMER_LOAD);
77 /* Enable to start timer */
78 writel(1, priv->base + STF_TIMER_ENABLE);
79
80 return 0;
81}
82
83static const struct udevice_id starfive_ids[] = {
84 { .compatible = "starfive,jh8100-timers" },
85 { }
86};
87
88U_BOOT_DRIVER(jh8100_starfive_timer) = {
89 .name = "starfive_timer",
90 .id = UCLASS_TIMER,
91 .of_match = starfive_ids,
92 .probe = starfive_probe,
93 .ops = &starfive_ops,
94 .priv_auto = sizeof(struct starfive_timer_priv),
95};