diff options
| author | Rafał Miłecki <zajec5@gmail.com> | 2014-10-29 10:05:06 +0100 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2014-11-24 07:45:08 +0100 |
| commit | 9d1d08646af4491aec41d40341930b9bfd62ffa9 (patch) | |
| tree | 811919fcf981ec96c185cf563c610147c5dc5fb2 | |
| parent | MIPS: Kconfig option to better exercise/debug hybrid FPRs (diff) | |
| download | linux-9d1d08646af4491aec41d40341930b9bfd62ffa9.tar.xz linux-9d1d08646af4491aec41d40341930b9bfd62ffa9.zip | |
MIPS: BCM47XX: Use mtd as an alternative way/API to get NVRAM content
NVRAM can be read using magic memory offset, but after all it's just a
flash partition. On platforms where NVRAM isn't needed early we can get
it using mtd subsystem.
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Acked-by: Hauke Mehrtens <hauke@hauke-m.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8266/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| -rw-r--r-- | arch/mips/bcm47xx/nvram.c | 42 |
1 files changed, 38 insertions, 4 deletions
diff --git a/arch/mips/bcm47xx/nvram.c b/arch/mips/bcm47xx/nvram.c index 21712fb40d72..8b6499100db3 100644 --- a/arch/mips/bcm47xx/nvram.c +++ b/arch/mips/bcm47xx/nvram.c @@ -13,12 +13,10 @@ #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 <linux/mtd/mtd.h> #include <bcm47xx_nvram.h> -#include <asm/mach-bcm47xx/bcm47xx.h> static char nvram_buf[NVRAM_SPACE]; static const u32 nvram_sizes[] = {0x8000, 0xF000, 0x10000}; @@ -123,7 +121,43 @@ int bcm47xx_nvram_init_from_mem(u32 base, u32 lim) static int nvram_init(void) { - /* TODO: Look for MTD "nvram" partition */ +#ifdef CONFIG_MTD + struct mtd_info *mtd; + struct nvram_header header; + size_t bytes_read; + int err, i; + + mtd = get_mtd_device_nm("nvram"); + if (IS_ERR(mtd)) + return -ENODEV; + + for (i = 0; i < ARRAY_SIZE(nvram_sizes); i++) { + loff_t from = mtd->size - nvram_sizes[i]; + + if (from < 0) + continue; + + err = mtd_read(mtd, from, sizeof(header), &bytes_read, + (uint8_t *)&header); + if (!err && header.magic == NVRAM_HEADER) { + u8 *dst = (uint8_t *)nvram_buf; + size_t len = header.len; + + if (header.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); + len = NVRAM_SPACE; + } + + err = mtd_read(mtd, from, len, &bytes_read, dst); + if (err) + return err; + memset(dst + bytes_read, 0x0, NVRAM_SPACE - bytes_read); + + return 0; + } + } +#endif return -ENXIO; } |