Commit | Line | Data |
---|---|---|
121915c4 WB |
1 | /* |
2 | * BCM947xx nvram variable access | |
3 | * | |
4 | * Copyright (C) 2005 Broadcom Corporation | |
5 | * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify it | |
8 | * under the terms of the GNU General Public License as published by the | |
9 | * Free Software Foundation; either version 2 of the License, or (at your | |
10 | * option) any later version. | |
11 | */ | |
12 | ||
13 | #include <linux/init.h> | |
14 | #include <linux/types.h> | |
15 | #include <linux/module.h> | |
16 | #include <linux/ssb/ssb.h> | |
17 | #include <linux/kernel.h> | |
18 | #include <linux/string.h> | |
19 | #include <asm/addrspace.h> | |
20 | #include <asm/mach-bcm47xx/nvram.h> | |
21 | #include <asm/mach-bcm47xx/bcm47xx.h> | |
22 | ||
23 | static char nvram_buf[NVRAM_SPACE]; | |
24 | ||
25 | /* Probe for NVRAM header */ | |
26 | static void __init early_nvram_init(void) | |
27 | { | |
28 | struct ssb_mipscore *mcore = &ssb_bcm47xx.mipscore; | |
29 | struct nvram_header *header; | |
30 | int i; | |
31 | u32 base, lim, off; | |
32 | u32 *src, *dst; | |
33 | ||
34 | base = mcore->flash_window; | |
35 | lim = mcore->flash_window_size; | |
36 | ||
37 | off = FLASH_MIN; | |
38 | while (off <= lim) { | |
39 | /* Windowed flash access */ | |
40 | header = (struct nvram_header *) | |
41 | KSEG1ADDR(base + off - NVRAM_SPACE); | |
42 | if (header->magic == NVRAM_HEADER) | |
43 | goto found; | |
44 | off <<= 1; | |
45 | } | |
46 | ||
47 | /* Try embedded NVRAM at 4 KB and 1 KB as last resorts */ | |
48 | header = (struct nvram_header *) KSEG1ADDR(base + 4096); | |
49 | if (header->magic == NVRAM_HEADER) | |
50 | goto found; | |
51 | ||
52 | header = (struct nvram_header *) KSEG1ADDR(base + 1024); | |
53 | if (header->magic == NVRAM_HEADER) | |
54 | goto found; | |
55 | ||
56 | return; | |
57 | ||
58 | found: | |
59 | src = (u32 *) header; | |
60 | dst = (u32 *) nvram_buf; | |
61 | for (i = 0; i < sizeof(struct nvram_header); i += 4) | |
62 | *dst++ = *src++; | |
63 | for (; i < header->len && i < NVRAM_SPACE; i += 4) | |
64 | *dst++ = le32_to_cpu(*src++); | |
65 | } | |
66 | ||
67 | int nvram_getenv(char *name, char *val, size_t val_len) | |
68 | { | |
69 | char *var, *value, *end, *eq; | |
70 | ||
71 | if (!name) | |
72 | return 1; | |
73 | ||
74 | if (!nvram_buf[0]) | |
75 | early_nvram_init(); | |
76 | ||
77 | /* Look for name=value and return value */ | |
78 | var = &nvram_buf[sizeof(struct nvram_header)]; | |
79 | end = nvram_buf + sizeof(nvram_buf) - 2; | |
80 | end[0] = end[1] = '\0'; | |
81 | for (; *var; var = value + strlen(value) + 1) { | |
82 | eq = strchr(var, '='); | |
83 | if (!eq) | |
84 | break; | |
85 | value = eq + 1; | |
86 | if ((eq - var) == strlen(name) && | |
87 | strncmp(var, name, (eq - var)) == 0) { | |
88 | snprintf(val, val_len, "%s", value); | |
89 | return 0; | |
90 | } | |
91 | } | |
92 | return 1; | |
93 | } | |
94 | EXPORT_SYMBOL(nvram_getenv); |