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gerrit.devboardsforandroid.linaro.org / platform / external / u-boot / f238b3f0fbc9ebc3a9702ddfc5ef22dff09f35d8 / . / drivers / watchdog / ast_wdt.c
blob: 477605e7222dfb1e1a094019d5a685149ba39e71 [file] [log] [blame]
Tom Rini83d290c2018-05-06 17:58:06 -0400[diff] [blame]1// SPDX-License-Identifier: GPL-2.0+
maxims@google.com1eb0a462017-04-17 12:00:22 -0700[diff] [blame]2/*
3 * Copyright 2017 Google, Inc
maxims@google.com1eb0a462017-04-17 12:00:22 -0700[diff] [blame]4 */
5
6#include <common.h>
7#include <dm.h>
8#include <errno.h>
9#include <wdt.h>
10#include <asm/io.h>
11#include <asm/arch/wdt.h>
12
13#define WDT_AST2500 2500
14#define WDT_AST2400 2400
15
maxims@google.com1eb0a462017-04-17 12:00:22 -0700[diff] [blame]16struct ast_wdt_priv {
17 struct ast_wdt *regs;
18};
19
20static int ast_wdt_start(struct udevice *dev, u64 timeout, ulong flags)
21{
22 struct ast_wdt_priv *priv = dev_get_priv(dev);
23 ulong driver_data = dev_get_driver_data(dev);
24 u32 reset_mode = ast_reset_mode_from_flags(flags);
25
26 clrsetbits_le32(&priv->regs->ctrl,
27 WDT_CTRL_RESET_MASK << WDT_CTRL_RESET_MODE_SHIFT,
28 reset_mode << WDT_CTRL_RESET_MODE_SHIFT);
29
30 if (driver_data >= WDT_AST2500 && reset_mode == WDT_CTRL_RESET_SOC)
31 writel(ast_reset_mask_from_flags(flags),
32 &priv->regs->reset_mask);
33
34 writel((u32) timeout, &priv->regs->counter_reload_val);
35 writel(WDT_COUNTER_RESTART_VAL, &priv->regs->counter_restart);
36 /*
37 * Setting CLK1MHZ bit is just for compatibility with ast2400 part.
38 * On ast2500 watchdog timer clock is fixed at 1MHz and the bit is
39 * read-only
40 */
41 setbits_le32(&priv->regs->ctrl,
42 WDT_CTRL_EN | WDT_CTRL_RESET | WDT_CTRL_CLK1MHZ);
43
44 return 0;
45}
46
47static int ast_wdt_stop(struct udevice *dev)
48{
49 struct ast_wdt_priv *priv = dev_get_priv(dev);
50
51 clrbits_le32(&priv->regs->ctrl, WDT_CTRL_EN);
52
53 return 0;
54}
55
56static int ast_wdt_reset(struct udevice *dev)
57{
58 struct ast_wdt_priv *priv = dev_get_priv(dev);
59
60 writel(WDT_COUNTER_RESTART_VAL, &priv->regs->counter_restart);
61
62 return 0;
63}
64
65static int ast_wdt_expire_now(struct udevice *dev, ulong flags)
66{
67 struct ast_wdt_priv *priv = dev_get_priv(dev);
68 int ret;
69
70 ret = ast_wdt_start(dev, 1, flags);
71 if (ret)
72 return ret;
73
74 while (readl(&priv->regs->ctrl) & WDT_CTRL_EN)
75 ;
76
77 return ast_wdt_stop(dev);
78}
79
80static int ast_wdt_ofdata_to_platdata(struct udevice *dev)
81{
82 struct ast_wdt_priv *priv = dev_get_priv(dev);
83
Simon Glassa821c4a2017-05-17 17:18:05 -0600[diff] [blame]84 priv->regs = devfdt_get_addr_ptr(dev);
maxims@google.com1eb0a462017-04-17 12:00:22 -0700[diff] [blame]85 if (IS_ERR(priv->regs))
86 return PTR_ERR(priv->regs);
87
88 return 0;
89}
90
91static const struct wdt_ops ast_wdt_ops = {
92 .start = ast_wdt_start,
93 .reset = ast_wdt_reset,
94 .stop = ast_wdt_stop,
95 .expire_now = ast_wdt_expire_now,
96};
97
98static const struct udevice_id ast_wdt_ids[] = {
99 { .compatible = "aspeed,wdt", .data = WDT_AST2500 },
100 { .compatible = "aspeed,ast2500-wdt", .data = WDT_AST2500 },
101 { .compatible = "aspeed,ast2400-wdt", .data = WDT_AST2400 },
102 {}
103};
104
105static int ast_wdt_probe(struct udevice *dev)
106{
107 debug("%s() wdt%u\n", __func__, dev->seq);
108 ast_wdt_stop(dev);
109
110 return 0;
111}
112
113U_BOOT_DRIVER(ast_wdt) = {
114 .name = "ast_wdt",
115 .id = UCLASS_WDT,
116 .of_match = ast_wdt_ids,
117 .probe = ast_wdt_probe,
118 .priv_auto_alloc_size = sizeof(struct ast_wdt_priv),
119 .ofdata_to_platdata = ast_wdt_ofdata_to_platdata,
120 .ops = &ast_wdt_ops,
121 .flags = DM_FLAG_PRE_RELOC,
122};