diff options
Diffstat (limited to 'drivers/firmware/broadcom/bcm47xx_nvram.c')
| -rw-r--r-- | drivers/firmware/broadcom/bcm47xx_nvram.c | 121 |
1 files changed, 68 insertions, 53 deletions
diff --git a/drivers/firmware/broadcom/bcm47xx_nvram.c b/drivers/firmware/broadcom/bcm47xx_nvram.c index 0b631e5b5b84..0ea5206be4c9 100644 --- a/drivers/firmware/broadcom/bcm47xx_nvram.c +++ b/drivers/firmware/broadcom/bcm47xx_nvram.c @@ -1,14 +1,10 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * BCM947xx nvram variable access * * Copyright (C) 2005 Broadcom Corporation * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org> * Copyright (C) 2010-2012 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/io.h> @@ -36,28 +32,48 @@ struct nvram_header { static char nvram_buf[NVRAM_SPACE]; static size_t nvram_len; -static const u32 nvram_sizes[] = {0x8000, 0xF000, 0x10000}; +static const u32 nvram_sizes[] = {0x6000, 0x8000, 0xF000, 0x10000}; -static u32 find_nvram_size(void __iomem *end) +/** + * bcm47xx_nvram_is_valid - check for a valid NVRAM at specified memory + */ +static bool bcm47xx_nvram_is_valid(void __iomem *nvram) { - struct nvram_header __iomem *header; - int i; + return ((struct nvram_header *)nvram)->magic == NVRAM_MAGIC; +} - for (i = 0; i < ARRAY_SIZE(nvram_sizes); i++) { - header = (struct nvram_header *)(end - nvram_sizes[i]); - if (header->magic == NVRAM_MAGIC) - return nvram_sizes[i]; +/** + * bcm47xx_nvram_copy - copy NVRAM to internal buffer + */ +static void bcm47xx_nvram_copy(void __iomem *nvram_start, size_t res_size) +{ + struct nvram_header __iomem *header = nvram_start; + size_t copy_size; + + copy_size = header->len; + if (copy_size > res_size) { + pr_err("The nvram size according to the header seems to be bigger than the partition on flash\n"); + copy_size = res_size; + } + if (copy_size >= NVRAM_SPACE) { + pr_err("nvram on flash (%zu bytes) is bigger than the reserved space in memory, will just copy the first %i bytes\n", + copy_size, NVRAM_SPACE - 1); + copy_size = NVRAM_SPACE - 1; } - return 0; + __ioread32_copy(nvram_buf, nvram_start, DIV_ROUND_UP(copy_size, 4)); + nvram_buf[NVRAM_SPACE - 1] = '\0'; + nvram_len = copy_size; } -/* Probe for NVRAM header */ -static int nvram_find_and_copy(void __iomem *iobase, u32 lim) +/** + * bcm47xx_nvram_find_and_copy - find NVRAM on flash mapping & copy it + */ +static int bcm47xx_nvram_find_and_copy(void __iomem *flash_start, size_t res_size) { - struct nvram_header __iomem *header; - u32 off; - u32 size; + size_t flash_size; + size_t offset; + int i; if (nvram_len) { pr_warn("nvram already initialized\n"); @@ -65,52 +81,52 @@ static int nvram_find_and_copy(void __iomem *iobase, u32 lim) } /* TODO: when nvram is on nand flash check for bad blocks first. */ - off = FLASH_MIN; - while (off <= lim) { - /* Windowed flash access */ - size = find_nvram_size(iobase + off); - if (size) { - header = (struct nvram_header *)(iobase + off - size); - goto found; + + /* Try every possible flash size and check for NVRAM at its end */ + for (flash_size = FLASH_MIN; flash_size <= res_size; flash_size <<= 1) { + for (i = 0; i < ARRAY_SIZE(nvram_sizes); i++) { + offset = flash_size - nvram_sizes[i]; + if (bcm47xx_nvram_is_valid(flash_start + offset)) + goto found; } - off <<= 1; } /* Try embedded NVRAM at 4 KB and 1 KB as last resorts */ - header = (struct nvram_header *)(iobase + 4096); - if (header->magic == NVRAM_MAGIC) { - size = NVRAM_SPACE; + + offset = 4096; + if (bcm47xx_nvram_is_valid(flash_start + offset)) goto found; - } - header = (struct nvram_header *)(iobase + 1024); - if (header->magic == NVRAM_MAGIC) { - size = NVRAM_SPACE; + offset = 1024; + if (bcm47xx_nvram_is_valid(flash_start + offset)) goto found; - } pr_err("no nvram found\n"); return -ENXIO; found: - __ioread32_copy(nvram_buf, header, sizeof(*header) / 4); - nvram_len = ((struct nvram_header *)(nvram_buf))->len; - if (nvram_len > size) { - pr_err("The nvram size according to the header seems to be bigger than the partition on flash\n"); - nvram_len = size; + bcm47xx_nvram_copy(flash_start + offset, res_size - offset); + + return 0; +} + +int bcm47xx_nvram_init_from_iomem(void __iomem *nvram_start, size_t res_size) +{ + if (nvram_len) { + pr_warn("nvram already initialized\n"); + return -EEXIST; } - if (nvram_len >= NVRAM_SPACE) { - pr_err("nvram on flash (%i bytes) is bigger than the reserved space in memory, will just copy the first %i bytes\n", - nvram_len, NVRAM_SPACE - 1); - nvram_len = NVRAM_SPACE - 1; + + if (!bcm47xx_nvram_is_valid(nvram_start)) { + pr_err("No valid NVRAM found\n"); + return -ENOENT; } - /* proceed reading data after header */ - __ioread32_copy(nvram_buf + sizeof(*header), header + 1, - DIV_ROUND_UP(nvram_len, 4)); - nvram_buf[NVRAM_SPACE - 1] = '\0'; + + bcm47xx_nvram_copy(nvram_start, res_size); return 0; } +EXPORT_SYMBOL_GPL(bcm47xx_nvram_init_from_iomem); /* * On bcm47xx we need access to the NVRAM very early, so we can't use mtd @@ -124,11 +140,11 @@ int bcm47xx_nvram_init_from_mem(u32 base, u32 lim) void __iomem *iobase; int err; - iobase = ioremap_nocache(base, lim); + iobase = ioremap(base, lim); if (!iobase) return -ENOMEM; - err = nvram_find_and_copy(iobase, lim); + err = bcm47xx_nvram_find_and_copy(iobase, lim); iounmap(iobase); @@ -152,8 +168,8 @@ static int nvram_init(void) header.len > sizeof(header)) { nvram_len = header.len; if (nvram_len >= NVRAM_SPACE) { - pr_err("nvram on flash (%i bytes) is bigger than the reserved space in memory, will just copy the first %i bytes\n", - header.len, NVRAM_SPACE); + pr_err("nvram on flash (%zu bytes) is bigger than the reserved space in memory, will just copy the first %i bytes\n", + nvram_len, NVRAM_SPACE); nvram_len = NVRAM_SPACE - 1; } @@ -239,4 +255,3 @@ char *bcm47xx_nvram_get_contents(size_t *nvram_size) } EXPORT_SYMBOL(bcm47xx_nvram_get_contents); -MODULE_LICENSE("GPL v2"); |