xref: /openbmc/u-boot/drivers/timer/cadence-ttc.c (revision 90c08fa0)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2018 Xilinx, Inc. (Michal Simek)
4  */
5 
6 #include <common.h>
7 #include <dm.h>
8 #include <errno.h>
9 #include <timer.h>
10 #include <asm/io.h>
11 
12 #define CNT_CNTRL_RESET		BIT(4)
13 
14 struct cadence_ttc_regs {
15 	u32 clk_cntrl1; /* 0x0 - Clock Control 1 */
16 	u32 clk_cntrl2; /* 0x4 - Clock Control 2 */
17 	u32 clk_cntrl3; /* 0x8 - Clock Control 3 */
18 	u32 counter_cntrl1; /* 0xC - Counter Control 1 */
19 	u32 counter_cntrl2; /* 0x10 - Counter Control 2 */
20 	u32 counter_cntrl3; /* 0x14 - Counter Control 3 */
21 	u32 counter_val1; /* 0x18 - Counter Control 1 */
22 	u32 counter_val2; /* 0x1C - Counter Control 2 */
23 	u32 counter_val3; /* 0x20 - Counter Control 3 */
24 	u32 reserved[15];
25 	u32 interrupt_enable1; /* 0x60 - Interrupt Enable 1 */
26 	u32 interrupt_enable2; /* 0x64 - Interrupt Enable 2 */
27 	u32 interrupt_enable3; /* 0x68 - Interrupt Enable 3 */
28 };
29 
30 struct cadence_ttc_priv {
31 	struct cadence_ttc_regs *regs;
32 };
33 
34 #if CONFIG_IS_ENABLED(BOOTSTAGE)
35 ulong timer_get_boot_us(void)
36 {
37 	u64 ticks = 0;
38 	u32 rate = 1;
39 	u64 us;
40 	int ret;
41 
42 	ret = dm_timer_init();
43 	if (!ret) {
44 		/* The timer is available */
45 		rate = timer_get_rate(gd->timer);
46 		timer_get_count(gd->timer, &ticks);
47 	} else {
48 		return 0;
49 	}
50 
51 	us = (ticks * 1000) / rate;
52 	return us;
53 }
54 #endif
55 
56 static int cadence_ttc_get_count(struct udevice *dev, u64 *count)
57 {
58 	struct cadence_ttc_priv *priv = dev_get_priv(dev);
59 
60 	*count = readl(&priv->regs->counter_val1);
61 
62 	return 0;
63 }
64 
65 static int cadence_ttc_probe(struct udevice *dev)
66 {
67 	struct cadence_ttc_priv *priv = dev_get_priv(dev);
68 
69 	/* Disable interrupts for sure */
70 	writel(0, &priv->regs->interrupt_enable1);
71 	writel(0, &priv->regs->interrupt_enable2);
72 	writel(0, &priv->regs->interrupt_enable3);
73 
74 	/* Make sure that clocks are configured properly without prescaller */
75 	writel(0, &priv->regs->clk_cntrl1);
76 	writel(0, &priv->regs->clk_cntrl2);
77 	writel(0, &priv->regs->clk_cntrl3);
78 
79 	/* Reset and enable this counter */
80 	writel(CNT_CNTRL_RESET, &priv->regs->counter_cntrl1);
81 
82 	return 0;
83 }
84 
85 static int cadence_ttc_ofdata_to_platdata(struct udevice *dev)
86 {
87 	struct cadence_ttc_priv *priv = dev_get_priv(dev);
88 
89 	priv->regs = map_physmem(dev_read_addr(dev),
90 				 sizeof(struct cadence_ttc_regs), MAP_NOCACHE);
91 	if (IS_ERR(priv->regs))
92 		return PTR_ERR(priv->regs);
93 
94 	return 0;
95 }
96 
97 static const struct timer_ops cadence_ttc_ops = {
98 	.get_count = cadence_ttc_get_count,
99 };
100 
101 static const struct udevice_id cadence_ttc_ids[] = {
102 	{ .compatible = "cdns,ttc" },
103 	{}
104 };
105 
106 U_BOOT_DRIVER(cadence_ttc) = {
107 	.name = "cadence_ttc",
108 	.id = UCLASS_TIMER,
109 	.of_match = cadence_ttc_ids,
110 	.ofdata_to_platdata = cadence_ttc_ofdata_to_platdata,
111 	.priv_auto_alloc_size = sizeof(struct cadence_ttc_priv),
112 	.probe = cadence_ttc_probe,
113 	.ops = &cadence_ttc_ops,
114 	.flags = DM_FLAG_PRE_RELOC,
115 };
116