Blame view
drivers/watchdog/txx9wdt.c
4.35 KB
d2912cb15
|
1 |
// SPDX-License-Identifier: GPL-2.0-only |
6f702fce3
|
2 3 4 5 |
/* * txx9wdt: A Hardware Watchdog Driver for TXx9 SoCs * * Copyright (C) 2007 Atsushi Nemoto <anemo@mba.ocn.ne.jp> |
6f702fce3
|
6 |
*/ |
27c766aaa
|
7 8 |
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
6f702fce3
|
9 10 11 |
#include <linux/module.h> #include <linux/moduleparam.h> #include <linux/types.h> |
6f702fce3
|
12 |
#include <linux/watchdog.h> |
6f702fce3
|
13 |
#include <linux/init.h> |
6f702fce3
|
14 15 16 17 18 |
#include <linux/platform_device.h> #include <linux/clk.h> #include <linux/err.h> #include <linux/io.h> #include <asm/txx9tmr.h> |
b92c803ec
|
19 20 21 |
#define WD_TIMER_CCD 7 /* 1/256 */ #define WD_TIMER_CLK (clk_get_rate(txx9_imclk) / (2 << WD_TIMER_CCD)) #define WD_MAX_TIMEOUT ((0xffffffff >> (32 - TXX9_TIMER_BITS)) / WD_TIMER_CLK) |
6f702fce3
|
22 |
#define TIMER_MARGIN 60 /* Default is 60 seconds */ |
b92c803ec
|
23 24 |
static unsigned int timeout = TIMER_MARGIN; /* in seconds */ module_param(timeout, uint, 0); |
6f702fce3
|
25 26 27 28 |
MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. " "(0<timeout<((2^" __MODULE_STRING(TXX9_TIMER_BITS) ")/(IMCLK/256)), " "default=" __MODULE_STRING(TIMER_MARGIN) ")"); |
86a1e1896
|
29 30 |
static bool nowayout = WATCHDOG_NOWAYOUT; module_param(nowayout, bool, 0); |
6f702fce3
|
31 32 33 |
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started " "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); |
6f702fce3
|
34 35 |
static struct txx9_tmr_reg __iomem *txx9wdt_reg; static struct clk *txx9_imclk; |
f8494e061
|
36 |
static DEFINE_SPINLOCK(txx9_lock); |
6f702fce3
|
37 |
|
d62458423
|
38 |
static int txx9wdt_ping(struct watchdog_device *wdt_dev) |
6f702fce3
|
39 |
{ |
8dc244f7d
|
40 |
spin_lock(&txx9_lock); |
6f702fce3
|
41 |
__raw_writel(TXx9_TMWTMR_TWIE | TXx9_TMWTMR_TWC, &txx9wdt_reg->wtmr); |
8dc244f7d
|
42 |
spin_unlock(&txx9_lock); |
d62458423
|
43 |
return 0; |
6f702fce3
|
44 |
} |
d62458423
|
45 |
static int txx9wdt_start(struct watchdog_device *wdt_dev) |
6f702fce3
|
46 |
{ |
8dc244f7d
|
47 |
spin_lock(&txx9_lock); |
b92c803ec
|
48 |
__raw_writel(WD_TIMER_CLK * wdt_dev->timeout, &txx9wdt_reg->cpra); |
6f702fce3
|
49 50 51 52 53 |
__raw_writel(WD_TIMER_CCD, &txx9wdt_reg->ccdr); __raw_writel(0, &txx9wdt_reg->tisr); /* clear pending interrupt */ __raw_writel(TXx9_TMTCR_TCE | TXx9_TMTCR_CCDE | TXx9_TMTCR_TMODE_WDOG, &txx9wdt_reg->tcr); __raw_writel(TXx9_TMWTMR_TWIE | TXx9_TMWTMR_TWC, &txx9wdt_reg->wtmr); |
8dc244f7d
|
54 |
spin_unlock(&txx9_lock); |
d62458423
|
55 |
return 0; |
6f702fce3
|
56 |
} |
d62458423
|
57 |
static int txx9wdt_stop(struct watchdog_device *wdt_dev) |
6f702fce3
|
58 |
{ |
8dc244f7d
|
59 |
spin_lock(&txx9_lock); |
6f702fce3
|
60 61 62 |
__raw_writel(TXx9_TMWTMR_WDIS, &txx9wdt_reg->wtmr); __raw_writel(__raw_readl(&txx9wdt_reg->tcr) & ~TXx9_TMTCR_TCE, &txx9wdt_reg->tcr); |
8dc244f7d
|
63 |
spin_unlock(&txx9_lock); |
6f702fce3
|
64 65 |
return 0; } |
d62458423
|
66 67 |
static int txx9wdt_set_timeout(struct watchdog_device *wdt_dev, unsigned int new_timeout) |
6f702fce3
|
68 |
{ |
b92c803ec
|
69 |
wdt_dev->timeout = new_timeout; |
d62458423
|
70 71 72 |
txx9wdt_stop(wdt_dev); txx9wdt_start(wdt_dev); return 0; |
6f702fce3
|
73 |
} |
d62458423
|
74 75 76 77 |
static const struct watchdog_info txx9wdt_info = { .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, .identity = "Hardware Watchdog for TXx9", }; |
6f702fce3
|
78 |
|
d62458423
|
79 80 81 82 83 84 |
static const struct watchdog_ops txx9wdt_ops = { .owner = THIS_MODULE, .start = txx9wdt_start, .stop = txx9wdt_stop, .ping = txx9wdt_ping, .set_timeout = txx9wdt_set_timeout, |
6f702fce3
|
85 |
}; |
d62458423
|
86 87 88 |
static struct watchdog_device txx9wdt = { .info = &txx9wdt_info, .ops = &txx9wdt_ops, |
6f702fce3
|
89 |
}; |
6f702fce3
|
90 91 |
static int __init txx9wdt_probe(struct platform_device *dev) { |
6f702fce3
|
92 93 94 95 96 97 98 99 |
int ret; txx9_imclk = clk_get(NULL, "imbus_clk"); if (IS_ERR(txx9_imclk)) { ret = PTR_ERR(txx9_imclk); txx9_imclk = NULL; goto exit; } |
bfb1f46f6
|
100 |
ret = clk_prepare_enable(txx9_imclk); |
6f702fce3
|
101 102 103 104 105 |
if (ret) { clk_put(txx9_imclk); txx9_imclk = NULL; goto exit; } |
0f0a6a285
|
106 |
txx9wdt_reg = devm_platform_ioremap_resource(dev, 0); |
4c271bb67
|
107 108 |
if (IS_ERR(txx9wdt_reg)) { ret = PTR_ERR(txx9wdt_reg); |
6f702fce3
|
109 110 |
goto exit; } |
b92c803ec
|
111 112 113 |
if (timeout < 1 || timeout > WD_MAX_TIMEOUT) timeout = TIMER_MARGIN; txx9wdt.timeout = timeout; |
d62458423
|
114 115 |
txx9wdt.min_timeout = 1; txx9wdt.max_timeout = WD_MAX_TIMEOUT; |
6551881c8
|
116 |
txx9wdt.parent = &dev->dev; |
d62458423
|
117 118 119 120 121 |
watchdog_set_nowayout(&txx9wdt, nowayout); ret = watchdog_register_device(&txx9wdt); if (ret) goto exit; |
27c766aaa
|
122 123 124 |
pr_info("Hardware Watchdog Timer: timeout=%d sec (max %ld) (nowayout= %d) ", timeout, WD_MAX_TIMEOUT, nowayout); |
6f702fce3
|
125 126 |
return 0; |
6f702fce3
|
127 128 |
exit: if (txx9_imclk) { |
bfb1f46f6
|
129 |
clk_disable_unprepare(txx9_imclk); |
6f702fce3
|
130 131 132 133 134 135 136 |
clk_put(txx9_imclk); } return ret; } static int __exit txx9wdt_remove(struct platform_device *dev) { |
d62458423
|
137 |
watchdog_unregister_device(&txx9wdt); |
bfb1f46f6
|
138 |
clk_disable_unprepare(txx9_imclk); |
6f702fce3
|
139 140 141 |
clk_put(txx9_imclk); return 0; } |
168b5251a
|
142 143 |
static void txx9wdt_shutdown(struct platform_device *dev) { |
d62458423
|
144 |
txx9wdt_stop(&txx9wdt); |
168b5251a
|
145 |
} |
6f702fce3
|
146 147 |
static struct platform_driver txx9wdt_driver = { .remove = __exit_p(txx9wdt_remove), |
168b5251a
|
148 |
.shutdown = txx9wdt_shutdown, |
6f702fce3
|
149 150 |
.driver = { .name = "txx9wdt", |
6f702fce3
|
151 152 |
}, }; |
1cb9204cc
|
153 |
module_platform_driver_probe(txx9wdt_driver, txx9wdt_probe); |
6f702fce3
|
154 155 156 |
MODULE_DESCRIPTION("TXx9 Watchdog Driver"); MODULE_LICENSE("GPL"); |
f37d193c7
|
157 |
MODULE_ALIAS("platform:txx9wdt"); |