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Diffstat (limited to 'Documentation/mmc/mmc-dev-parts.txt')
| -rw-r--r-- | Documentation/mmc/mmc-dev-parts.txt | 40 |
1 files changed, 0 insertions, 40 deletions
diff --git a/Documentation/mmc/mmc-dev-parts.txt b/Documentation/mmc/mmc-dev-parts.txt deleted file mode 100644 index f08d078d43cf..000000000000 --- a/Documentation/mmc/mmc-dev-parts.txt +++ /dev/null @@ -1,40 +0,0 @@ -SD and MMC Device Partitions -============================ - -Device partitions are additional logical block devices present on the -SD/MMC device. - -As of this writing, MMC boot partitions as supported and exposed as -/dev/mmcblkXboot0 and /dev/mmcblkXboot1, where X is the index of the -parent /dev/mmcblkX. - -MMC Boot Partitions -=================== - -Read and write access is provided to the two MMC boot partitions. Due to -the sensitive nature of the boot partition contents, which often store -a bootloader or bootloader configuration tables crucial to booting the -platform, write access is disabled by default to reduce the chance of -accidental bricking. - -To enable write access to /dev/mmcblkXbootY, disable the forced read-only -access with: - -echo 0 > /sys/block/mmcblkXbootY/force_ro - -To re-enable read-only access: - -echo 1 > /sys/block/mmcblkXbootY/force_ro - -The boot partitions can also be locked read only until the next power on, -with: - -echo 1 > /sys/block/mmcblkXbootY/ro_lock_until_next_power_on - -This is a feature of the card and not of the kernel. If the card does -not support boot partition locking, the file will not exist. If the -feature has been disabled on the card, the file will be read-only. - -The boot partitions can also be locked permanently, but this feature is -not accessible through sysfs in order to avoid accidental or malicious -bricking. |