| /* |
| * BCM947xx nvram variable access |
| * |
| * Copyright (C) 2005 Broadcom Corporation |
| * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org> |
| * Copyright (C) 2010-2011 Hauke Mehrtens <hauke@hauke-m.de> |
| * |
| * 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/types.h> |
| #include <linux/module.h> |
| #include <linux/ssb/ssb.h> |
| #include <linux/kernel.h> |
| #include <linux/string.h> |
| #include <asm/addrspace.h> |
| #include <asm/mach-bcm47xx/nvram.h> |
| #include <asm/mach-bcm47xx/bcm47xx.h> |
| |
| static char nvram_buf[NVRAM_SPACE]; |
| |
| static int nvram_find_and_copy(u32 base, u32 lim) |
| { |
| struct nvram_header *header; |
| int i; |
| u32 off; |
| u32 *src, *dst; |
| |
| off = FLASH_MIN; |
| 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 -ENXIO; |
| |
| 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++); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_BCM47XX_SSB |
| static int nvram_init_ssb(void) |
| { |
| struct ssb_mipscore *mcore = &bcm47xx_bus.ssb.mipscore; |
| u32 base; |
| u32 lim; |
| |
| if (mcore->pflash.present) { |
| base = mcore->pflash.window; |
| lim = mcore->pflash.window_size; |
| } else { |
| pr_err("Couldn't find supported flash memory\n"); |
| return -ENXIO; |
| } |
| |
| return nvram_find_and_copy(base, lim); |
| } |
| #endif |
| |
| #ifdef CONFIG_BCM47XX_BCMA |
| static int nvram_init_bcma(void) |
| { |
| struct bcma_drv_cc *cc = &bcm47xx_bus.bcma.bus.drv_cc; |
| u32 base; |
| u32 lim; |
| |
| if (cc->pflash.present) { |
| base = cc->pflash.window; |
| lim = cc->pflash.window_size; |
| #ifdef CONFIG_BCMA_SFLASH |
| } else if (cc->sflash.present) { |
| base = cc->sflash.window; |
| lim = cc->sflash.size; |
| #endif |
| } else { |
| pr_err("Couldn't find supported flash memory\n"); |
| return -ENXIO; |
| } |
| |
| return nvram_find_and_copy(base, lim); |
| } |
| #endif |
| |
| static int early_nvram_init(void) |
| { |
| switch (bcm47xx_bus_type) { |
| #ifdef CONFIG_BCM47XX_SSB |
| case BCM47XX_BUS_TYPE_SSB: |
| return nvram_init_ssb(); |
| #endif |
| #ifdef CONFIG_BCM47XX_BCMA |
| case BCM47XX_BUS_TYPE_BCMA: |
| return nvram_init_bcma(); |
| #endif |
| } |
| return -ENXIO; |
| } |
| |
| int nvram_getenv(char *name, char *val, size_t val_len) |
| { |
| char *var, *value, *end, *eq; |
| int err; |
| |
| if (!name) |
| return -EINVAL; |
| |
| if (!nvram_buf[0]) { |
| err = early_nvram_init(); |
| if (err) |
| return err; |
| } |
| |
| /* 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) { |
| eq = strchr(var, '='); |
| if (!eq) |
| break; |
| value = eq + 1; |
| if ((eq - var) == strlen(name) && |
| strncmp(var, name, (eq - var)) == 0) { |
| return snprintf(val, val_len, "%s", value); |
| } |
| } |
| return -ENOENT; |
| } |
| EXPORT_SYMBOL(nvram_getenv); |