blob: 7e11465a570c48dbffa90de0f0ddc9f73bbeaed8 [file] [log] [blame]
Tom Rini83d290c2018-05-06 17:58:06 -04001// SPDX-License-Identifier: GPL-2.0+
maxims@google.com1eb0a462017-04-17 12:00:22 -07002/*
3 * Copyright 2017 Google, Inc
maxims@google.com1eb0a462017-04-17 12:00:22 -07004 */
5
6#include <common.h>
7#include <dm.h>
8#include <errno.h>
Simon Glassf7ae49f2020-05-10 11:40:05 -06009#include <log.h>
maxims@google.com1eb0a462017-04-17 12:00:22 -070010#include <wdt.h>
11#include <asm/io.h>
12#include <asm/arch/wdt.h>
Simon Glass61b29b82020-02-03 07:36:15 -070013#include <linux/err.h>
maxims@google.com1eb0a462017-04-17 12:00:22 -070014
15#define WDT_AST2500 2500
16#define WDT_AST2400 2400
17
maxims@google.com1eb0a462017-04-17 12:00:22 -070018struct ast_wdt_priv {
19 struct ast_wdt *regs;
20};
21
22static int ast_wdt_start(struct udevice *dev, u64 timeout, ulong flags)
23{
24 struct ast_wdt_priv *priv = dev_get_priv(dev);
25 ulong driver_data = dev_get_driver_data(dev);
26 u32 reset_mode = ast_reset_mode_from_flags(flags);
27
Joel Stanley894e2352019-06-06 17:08:45 +093028 /* 32 bits at 1MHz is 4294967ms */
29 timeout = min_t(u64, timeout, 4294967);
30
31 /* WDT counts in ticks of 1MHz clock. 1ms / 1e3 * 1e6 */
32 timeout *= 1000;
33
maxims@google.com1eb0a462017-04-17 12:00:22 -070034 clrsetbits_le32(&priv->regs->ctrl,
35 WDT_CTRL_RESET_MASK << WDT_CTRL_RESET_MODE_SHIFT,
36 reset_mode << WDT_CTRL_RESET_MODE_SHIFT);
37
38 if (driver_data >= WDT_AST2500 && reset_mode == WDT_CTRL_RESET_SOC)
39 writel(ast_reset_mask_from_flags(flags),
40 &priv->regs->reset_mask);
41
42 writel((u32) timeout, &priv->regs->counter_reload_val);
43 writel(WDT_COUNTER_RESTART_VAL, &priv->regs->counter_restart);
44 /*
45 * Setting CLK1MHZ bit is just for compatibility with ast2400 part.
46 * On ast2500 watchdog timer clock is fixed at 1MHz and the bit is
47 * read-only
48 */
49 setbits_le32(&priv->regs->ctrl,
50 WDT_CTRL_EN | WDT_CTRL_RESET | WDT_CTRL_CLK1MHZ);
51
52 return 0;
53}
54
55static int ast_wdt_stop(struct udevice *dev)
56{
57 struct ast_wdt_priv *priv = dev_get_priv(dev);
58
59 clrbits_le32(&priv->regs->ctrl, WDT_CTRL_EN);
60
Cédric Le Goatere1a8dfd2018-10-16 13:57:11 +020061 writel(WDT_RESET_DEFAULT, &priv->regs->reset_mask);
maxims@google.com1eb0a462017-04-17 12:00:22 -070062 return 0;
63}
64
65static int ast_wdt_reset(struct udevice *dev)
66{
67 struct ast_wdt_priv *priv = dev_get_priv(dev);
68
69 writel(WDT_COUNTER_RESTART_VAL, &priv->regs->counter_restart);
70
71 return 0;
72}
73
74static int ast_wdt_expire_now(struct udevice *dev, ulong flags)
75{
76 struct ast_wdt_priv *priv = dev_get_priv(dev);
77 int ret;
78
79 ret = ast_wdt_start(dev, 1, flags);
80 if (ret)
81 return ret;
82
83 while (readl(&priv->regs->ctrl) & WDT_CTRL_EN)
84 ;
85
86 return ast_wdt_stop(dev);
87}
88
89static int ast_wdt_ofdata_to_platdata(struct udevice *dev)
90{
91 struct ast_wdt_priv *priv = dev_get_priv(dev);
92
Simon Glassa821c4a2017-05-17 17:18:05 -060093 priv->regs = devfdt_get_addr_ptr(dev);
maxims@google.com1eb0a462017-04-17 12:00:22 -070094 if (IS_ERR(priv->regs))
95 return PTR_ERR(priv->regs);
96
97 return 0;
98}
99
100static const struct wdt_ops ast_wdt_ops = {
101 .start = ast_wdt_start,
102 .reset = ast_wdt_reset,
103 .stop = ast_wdt_stop,
104 .expire_now = ast_wdt_expire_now,
105};
106
107static const struct udevice_id ast_wdt_ids[] = {
108 { .compatible = "aspeed,wdt", .data = WDT_AST2500 },
109 { .compatible = "aspeed,ast2500-wdt", .data = WDT_AST2500 },
110 { .compatible = "aspeed,ast2400-wdt", .data = WDT_AST2400 },
111 {}
112};
113
114static int ast_wdt_probe(struct udevice *dev)
115{
116 debug("%s() wdt%u\n", __func__, dev->seq);
117 ast_wdt_stop(dev);
118
119 return 0;
120}
121
122U_BOOT_DRIVER(ast_wdt) = {
123 .name = "ast_wdt",
124 .id = UCLASS_WDT,
125 .of_match = ast_wdt_ids,
126 .probe = ast_wdt_probe,
127 .priv_auto_alloc_size = sizeof(struct ast_wdt_priv),
128 .ofdata_to_platdata = ast_wdt_ofdata_to_platdata,
129 .ops = &ast_wdt_ops,
maxims@google.com1eb0a462017-04-17 12:00:22 -0700130};