1 /*
2  * Copyright (C) 2017 Theobroma Systems Design und Consulting GmbH
3  *
4  * SPDX-License-Identifier: GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <dm/ofnode.h>
10 #include <mapmem.h>
11 #include <asm/arch/timer.h>
12 #include <dt-structs.h>
13 #include <timer.h>
14 #include <asm/io.h>
15 
16 DECLARE_GLOBAL_DATA_PTR;
17 
18 #if CONFIG_IS_ENABLED(OF_PLATDATA)
19 struct rockchip_timer_plat {
20 	struct dtd_rockchip_rk3368_timer dtd;
21 };
22 #endif
23 
24 /* Driver private data. Contains timer id. Could be either 0 or 1. */
25 struct rockchip_timer_priv {
26 	struct rk_timer *timer;
27 };
28 
29 static inline int64_t rockchip_timer_get_curr_value(struct rk_timer *timer)
30 {
31 	uint64_t timebase_h, timebase_l;
32 	uint64_t cntr;
33 
34 	timebase_l = readl(&timer->timer_curr_value0);
35 	timebase_h = readl(&timer->timer_curr_value1);
36 
37 	cntr = timebase_h << 32 | timebase_l;
38 	return cntr;
39 }
40 
41 #if CONFIG_IS_ENABLED(BOOTSTAGE)
42 ulong timer_get_boot_us(void)
43 {
44 	uint64_t  ticks = 0;
45 	uint32_t  rate;
46 	uint64_t  us;
47 	int ret;
48 
49 	ret = dm_timer_init();
50 
51 	if (!ret) {
52 		/* The timer is available */
53 		rate = timer_get_rate(gd->timer);
54 		timer_get_count(gd->timer, &ticks);
55 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
56 	} else if (ret == -EAGAIN) {
57 		/* We have been called so early that the DM is not ready,... */
58 		ofnode node = offset_to_ofnode(-1);
59 		struct rk_timer *timer = NULL;
60 
61 		/*
62 		 * ... so we try to access the raw timer, if it is specified
63 		 * via the tick-timer property in /chosen.
64 		 */
65 		node = ofnode_get_chosen_node("tick-timer");
66 		if (!ofnode_valid(node)) {
67 			debug("%s: no /chosen/tick-timer\n", __func__);
68 			return 0;
69 		}
70 
71 		timer = (struct rk_timer *)ofnode_get_addr(node);
72 
73 		/* This timer is down-counting */
74 		ticks = ~0uLL - rockchip_timer_get_curr_value(timer);
75 		if (ofnode_read_u32(node, "clock-frequency", &rate)) {
76 			debug("%s: could not read clock-frequency\n", __func__);
77 			return 0;
78 		}
79 #endif
80 	} else {
81 		return 0;
82 	}
83 
84 	us = (ticks * 1000) / rate;
85 	return us;
86 }
87 #endif
88 
89 static int rockchip_timer_get_count(struct udevice *dev, u64 *count)
90 {
91 	struct rockchip_timer_priv *priv = dev_get_priv(dev);
92 	uint64_t cntr = rockchip_timer_get_curr_value(priv->timer);
93 
94 	/* timers are down-counting */
95 	*count = ~0ull - cntr;
96 	return 0;
97 }
98 
99 static int rockchip_clk_ofdata_to_platdata(struct udevice *dev)
100 {
101 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
102 	struct rockchip_timer_priv *priv = dev_get_priv(dev);
103 
104 	priv->timer = dev_read_addr_ptr(dev);
105 	if (!priv->timer)
106 		return -ENOENT;
107 #endif
108 
109 	return 0;
110 }
111 
112 static int rockchip_timer_start(struct udevice *dev)
113 {
114 	struct rockchip_timer_priv *priv = dev_get_priv(dev);
115 	const uint64_t reload_val = ~0uLL;
116 	const uint32_t reload_val_l = reload_val & 0xffffffff;
117 	const uint32_t reload_val_h = reload_val >> 32;
118 
119 	/* don't reinit, if the timer is already running and set up */
120 	if ((readl(&priv->timer->timer_ctrl_reg) & 1) == 1 &&
121 	    (readl(&priv->timer->timer_load_count0) == reload_val_l) &&
122 	    (readl(&priv->timer->timer_load_count1) == reload_val_h))
123 		return 0;
124 
125 	/* disable timer and reset all control */
126 	writel(0, &priv->timer->timer_ctrl_reg);
127 	/* write reload value */
128 	writel(reload_val_l, &priv->timer->timer_load_count0);
129 	writel(reload_val_h, &priv->timer->timer_load_count1);
130 	/* enable timer */
131 	writel(1, &priv->timer->timer_ctrl_reg);
132 
133 	return 0;
134 }
135 
136 static int rockchip_timer_probe(struct udevice *dev)
137 {
138 #if CONFIG_IS_ENABLED(OF_PLATDATA)
139 	struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
140 	struct rockchip_timer_priv *priv = dev_get_priv(dev);
141 	struct rockchip_timer_plat *plat = dev_get_platdata(dev);
142 
143 	priv->timer = map_sysmem(plat->dtd.reg[0], plat->dtd.reg[1]);
144 	uc_priv->clock_rate = plat->dtd.clock_frequency;
145 #endif
146 
147 	return rockchip_timer_start(dev);
148 }
149 
150 static const struct timer_ops rockchip_timer_ops = {
151 	.get_count = rockchip_timer_get_count,
152 };
153 
154 static const struct udevice_id rockchip_timer_ids[] = {
155 	{ .compatible = "rockchip,rk3368-timer" },
156 	{}
157 };
158 
159 U_BOOT_DRIVER(rockchip_rk3368_timer) = {
160 	.name	= "rockchip_rk3368_timer",
161 	.id	= UCLASS_TIMER,
162 	.of_match = rockchip_timer_ids,
163 	.probe = rockchip_timer_probe,
164 	.ops	= &rockchip_timer_ops,
165 	.flags = DM_FLAG_PRE_RELOC,
166 	.priv_auto_alloc_size = sizeof(struct rockchip_timer_priv),
167 #if CONFIG_IS_ENABLED(OF_PLATDATA)
168 	.platdata_auto_alloc_size = sizeof(struct rockchip_timer_plat),
169 #endif
170 	.ofdata_to_platdata = rockchip_clk_ofdata_to_platdata,
171 };
172