Commit | Line | Data |
---|---|---|
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> | |
10 | #include <asm/io.h> | |
11 | #include <asm/proc-fns.h> | |
12 | ||
a09e64fb | 13 | #include <mach/pxa-regs.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 | ||
23 | int init_gpio_reset(int gpio) | |
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 | ||
33 | rc = gpio_direction_input(gpio); | |
34 | if (rc) { | |
35 | printk(KERN_ERR "Can't configure reset_gpio for input\n"); | |
36 | gpio_free(gpio); | |
37 | goto out; | |
38 | } | |
39 | ||
40 | out: | |
41 | if (!rc) | |
42 | reset_gpio = gpio; | |
43 | ||
44 | return rc; | |
45 | } | |
46 | ||
47 | /* | |
48 | * Trigger GPIO reset. | |
49 | * This covers various types of logic connecting gpio pin | |
50 | * to RESET pins (nRESET or GPIO_RESET): | |
51 | */ | |
52 | static void do_gpio_reset(void) | |
53 | { | |
54 | BUG_ON(reset_gpio == -1); | |
55 | ||
56 | /* drive it low */ | |
57 | gpio_direction_output(reset_gpio, 0); | |
58 | mdelay(2); | |
59 | /* rising edge or drive high */ | |
60 | gpio_set_value(reset_gpio, 1); | |
61 | mdelay(2); | |
62 | /* falling edge */ | |
63 | gpio_set_value(reset_gpio, 0); | |
64 | ||
65 | /* give it some time */ | |
66 | mdelay(10); | |
67 | ||
68 | WARN_ON(1); | |
69 | /* fallback */ | |
70 | do_hw_reset(); | |
71 | } | |
72 | ||
73 | static void do_hw_reset(void) | |
74 | { | |
75 | /* Initialize the watchdog and let it fire */ | |
76 | OWER = OWER_WME; | |
77 | OSSR = OSSR_M3; | |
78 | OSMR3 = OSCR + 368640; /* ... in 100 ms */ | |
79 | } | |
80 | ||
81 | void arch_reset(char mode) | |
82 | { | |
04fef228 | 83 | clear_reset_status(RESET_STATUS_ALL); |
75f10b46 DB |
84 | |
85 | switch (mode) { | |
86 | case 's': | |
87 | /* Jump into ROM at address 0 */ | |
88 | cpu_reset(0); | |
89 | break; | |
90 | case 'h': | |
91 | do_hw_reset(); | |
92 | break; | |
93 | case 'g': | |
94 | do_gpio_reset(); | |
95 | break; | |
96 | } | |
97 | } | |
98 |