Commit | Line | Data |
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75f10b46 DB |
1 | /* |
2 | * This program is free software; you can redistribute it and/or modify | |
3 | * it under the terms of the GNU General Public License version 2 as | |
4 | * published by the Free Software Foundation. | |
5 | */ | |
6 | #include <linux/kernel.h> | |
7 | #include <linux/module.h> | |
8 | #include <linux/delay.h> | |
9 | #include <linux/gpio.h> | |
fced80c7 | 10 | #include <linux/io.h> |
75f10b46 DB |
11 | #include <asm/proc-fns.h> |
12 | ||
5bf3df3f | 13 | #include <mach/regs-ost.h> |
afd2fc02 | 14 | #include <mach/reset.h> |
75f10b46 | 15 | |
04fef228 EM |
16 | unsigned int reset_status; |
17 | EXPORT_SYMBOL(reset_status); | |
75f10b46 DB |
18 | |
19 | static void do_hw_reset(void); | |
20 | ||
21 | static int reset_gpio = -1; | |
22 | ||
216e3b7a | 23 | int init_gpio_reset(int gpio, int output, int level) |
75f10b46 DB |
24 | { |
25 | int rc; | |
26 | ||
27 | rc = gpio_request(gpio, "reset generator"); | |
28 | if (rc) { | |
29 | printk(KERN_ERR "Can't request reset_gpio\n"); | |
30 | goto out; | |
31 | } | |
32 | ||
69fc7eed | 33 | if (output) |
216e3b7a | 34 | rc = gpio_direction_output(gpio, level); |
69fc7eed DB |
35 | else |
36 | rc = gpio_direction_input(gpio); | |
75f10b46 | 37 | if (rc) { |
69fc7eed | 38 | printk(KERN_ERR "Can't configure reset_gpio\n"); |
75f10b46 DB |
39 | gpio_free(gpio); |
40 | goto out; | |
41 | } | |
42 | ||
43 | out: | |
44 | if (!rc) | |
45 | reset_gpio = gpio; | |
46 | ||
47 | return rc; | |
48 | } | |
49 | ||
50 | /* | |
51 | * Trigger GPIO reset. | |
52 | * This covers various types of logic connecting gpio pin | |
53 | * to RESET pins (nRESET or GPIO_RESET): | |
54 | */ | |
55 | static void do_gpio_reset(void) | |
56 | { | |
57 | BUG_ON(reset_gpio == -1); | |
58 | ||
59 | /* drive it low */ | |
60 | gpio_direction_output(reset_gpio, 0); | |
61 | mdelay(2); | |
62 | /* rising edge or drive high */ | |
63 | gpio_set_value(reset_gpio, 1); | |
64 | mdelay(2); | |
65 | /* falling edge */ | |
66 | gpio_set_value(reset_gpio, 0); | |
67 | ||
68 | /* give it some time */ | |
69 | mdelay(10); | |
70 | ||
71 | WARN_ON(1); | |
72 | /* fallback */ | |
73 | do_hw_reset(); | |
74 | } | |
75 | ||
76 | static void do_hw_reset(void) | |
77 | { | |
78 | /* Initialize the watchdog and let it fire */ | |
79 | OWER = OWER_WME; | |
80 | OSSR = OSSR_M3; | |
81 | OSMR3 = OSCR + 368640; /* ... in 100 ms */ | |
82 | } | |
83 | ||
be093beb | 84 | void arch_reset(char mode, const char *cmd) |
75f10b46 | 85 | { |
04fef228 | 86 | clear_reset_status(RESET_STATUS_ALL); |
75f10b46 DB |
87 | |
88 | switch (mode) { | |
89 | case 's': | |
90 | /* Jump into ROM at address 0 */ | |
91 | cpu_reset(0); | |
92 | break; | |
75f10b46 DB |
93 | case 'g': |
94 | do_gpio_reset(); | |
95 | break; | |
28105fda JK |
96 | case 'h': |
97 | default: | |
98 | do_hw_reset(); | |
99 | break; | |
75f10b46 DB |
100 | } |
101 | } | |
102 |