diff options
Diffstat (limited to 'target/linux/brcm47xx/files/arch/mips/bcm947xx/nvram.c')
-rw-r--r-- | target/linux/brcm47xx/files/arch/mips/bcm947xx/nvram.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/target/linux/brcm47xx/files/arch/mips/bcm947xx/nvram.c b/target/linux/brcm47xx/files/arch/mips/bcm947xx/nvram.c new file mode 100644 index 0000000000..3f32ad9d6e --- /dev/null +++ b/target/linux/brcm47xx/files/arch/mips/bcm947xx/nvram.c @@ -0,0 +1,125 @@ +/* + * BCM947xx nvram variable access + * + * Copyright 2005, Broadcom Corporation + * Copyright 2006, Felix Fietkau <nbd@openwrt.org> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/ssb/ssb.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/interrupt.h> +#include <linux/spinlock.h> +#include <linux/slab.h> +#include <asm/byteorder.h> +#include <asm/bootinfo.h> +#include <asm/addrspace.h> +#include <asm/io.h> +#include <asm/uaccess.h> + +#include <nvram.h> + +#define MB * 1048576 +extern struct ssb_bus ssb; + +static char nvram_buf[NVRAM_SPACE]; +static int cfe_env; +extern char *cfe_env_get(char *nv_buf, const char *name); + +/* Probe for NVRAM header */ +static void __init early_nvram_init(void) +{ + struct ssb_mipscore *mcore = &ssb.mipscore; + struct nvram_header *header; + int i; + u32 base, lim, off; + u32 *src, *dst; + + base = mcore->flash_window; + lim = mcore->flash_window_size; + cfe_env = 0; + + + /* XXX: hack for supporting the CFE environment stuff on WGT634U */ + if (lim >= 8 MB) { + src = (u32 *) KSEG1ADDR(base + 8 MB - 0x2000); + dst = (u32 *) nvram_buf; + + if ((*src & 0xff00ff) == 0x000001) { + printk("early_nvram_init: WGT634U NVRAM found.\n"); + + for (i = 0; i < 0x1ff0; i++) { + if (*src == 0xFFFFFFFF) + break; + *dst++ = *src++; + } + cfe_env = 1; + return; + } + } + + off = 0x20000; + while (off <= lim) { + /* Windowed flash access */ + header = (struct nvram_header *) KSEG1ADDR(base + off - NVRAM_SPACE); + if (header->magic == NVRAM_HEADER) + goto found; + off <<= 1; + } + + /* Try embedded NVRAM at 4 KB and 1 KB as last resorts */ + header = (struct nvram_header *) KSEG1ADDR(base + 4096); + if (header->magic == NVRAM_HEADER) + goto found; + + header = (struct nvram_header *) KSEG1ADDR(base + 1024); + if (header->magic == NVRAM_HEADER) + goto found; + + return; + +found: + src = (u32 *) header; + dst = (u32 *) nvram_buf; + for (i = 0; i < sizeof(struct nvram_header); i += 4) + *dst++ = *src++; + for (; i < header->len && i < NVRAM_SPACE; i += 4) + *dst++ = le32_to_cpu(*src++); +} + +char *nvram_get(const char *name) +{ + char *var, *value, *end, *eq; + + if (!name) + return NULL; + + if (!nvram_buf[0]) + early_nvram_init(); + + if (cfe_env) + return cfe_env_get(nvram_buf, name); + + /* Look for name=value and return value */ + var = &nvram_buf[sizeof(struct nvram_header)]; + end = nvram_buf + sizeof(nvram_buf) - 2; + end[0] = end[1] = '\0'; + for (; *var; var = value + strlen(value) + 1) { + if (!(eq = strchr(var, '='))) + break; + value = eq + 1; + if ((eq - var) == strlen(name) && strncmp(var, name, (eq - var)) == 0) + return value; + } + + return NULL; +} + +EXPORT_SYMBOL(nvram_get); |